CN106990141A - A kind of stove water conductivity computational methods and system - Google Patents

Abstract

The present invention discloses a kind of stove water conductivity computational methods and system.Methods described calculates ionic strength first, then according to stove water intermediate ion institute charge number, the dielectric constant of solvent, stove coolant-temperature gage, the limiting molar conductivity computational constant coefficient of solvent viscosity and ion, the molar conductivity of strong electrolyte ion in stove water is calculated further according to the ionic strength and the constant coefficient, according to the limiting molar conductivity of ion, the degree of ionization and weak electrolyte concentration of weak electrolyte calculate the molar conductivity of weak electrolyte ion in stove water, the molar conductivity of molar conductivity and the weak electrolyte ion finally according to the strong electrolyte ion calculates stove water conductivity.The method and system that the present invention is provided, water conductivity of coming out of the stove can accurately be calculated, can also accurate perception stove water conductivity numerical value change, for the monitoring of stove water quality, the judgement of blow-off of boiler water and multi-parameter cooperate with Automatic Dosing control technology auxiliary control provides refer to and index.

Description

Furnace water conductivity calculation method and system

Technical Field

The invention relates to the technical field of monitoring of furnace water quality of a thermal power plant, in particular to a furnace water conductivity calculation method and a furnace water conductivity calculation system.

Background

With the rapid development of the power industry, the number of thermal power generating units in China is increasing continuously, and the primary premise is to ensure the qualified quality of boiler water in order to ensure the economic and safe operation of the thermal power generating units. In order to better ensure the quality of boiler water quality, many thermal power plants begin to develop and adopt a multi-parameter cooperative automatic dosing system.

The multi-parameter cooperative dosing system adopts an artificial intelligence fuzzy control technology, and can simultaneously meet the technical requirements of an automatic phosphate dosing device and the qualified requirements of operation control indexes of boiler water quality monitoring. The device has the functions of dosing quantity display, main control parameter display, dosing pump selection and operation display, parameter recording and printing, fault alarm and power-off parameter protection, RS485 serial port communication interface and the like; and meanwhile, the device has manual and automatic operation functions. The furnace water is fed in a multi-parameter cooperative automatic dosing control modeThe meter, the DD meter, the pH meter and the water supply flow signal are simultaneously accessed into the control system, and the unit operates at a stable loadAnd taking the DD table and the pH table as auxiliary control parameters to obtain a furnace water phosphate adding mathematical control model, and adjusting by adopting an intelligent PID.

In order to slow down the corrosion of the boiler water vapor system, a multi-parameter cooperative dosing system usually adds one or more agents of ammonia, phosphorus complex salt and sodium hydroxide into the boiler water, and the agents are added into the boiler water to form boiler water solution. Various positive and negative ions in the furnace aqueous solution have the ability to conduct electricity, and the magnitude of the conductivity is represented by the conductivity. The furnace water conductivity is generally used as an auxiliary parameter for comprehensively reflecting the water vapor quality of a thermodynamic system, in particular to a monitoring index of the furnace water quality, a judgment index of boiler pollution discharge and a multi-parameter cooperative automatic dosing control technology, so that accurate calculation of the furnace water conductivity is particularly important for safe and economic operation of a boiler system of a thermal power plant.

Disclosure of Invention

The invention aims to provide a furnace water conductivity calculation method and a furnace water conductivity calculation system, which can accurately calculate the conductivity of a multi-electrolyte furnace water solution, provide a reference index for monitoring the quality of furnace water, judging the pollution discharge of the furnace water and assisting control of a multi-parameter cooperative automatic dosing control technology, and are beneficial to the safe and economic operation of a boiler system of a thermal power plant.

In order to achieve the purpose, the invention provides the following scheme:

a furnace water conductivity calculation method, the method comprising:

calculating the ionic strength according to the real mass molar concentration of each ion in the furnace water and the charge number of each ion in the furnace water;

calculating a constant coefficient according to the number of charges carried by each ion in the furnace water, the dielectric constant of the solvent, the temperature of the furnace water, the viscosity of the solvent and the limit molar conductivity of each ion;

calculating the molar conductivity of strong electrolyte ions in the furnace water according to the ionic strength and the constant coefficient;

calculating the molar conductivity of weak electrolyte ions in the furnace water according to the limit molar conductivity of each ion, the ionization degree of the weak electrolyte and the concentration of the weak electrolyte;

and calculating the furnace water conductivity according to the molar conductivity of the strong electrolyte ions and the molar conductivity of the weak electrolyte ions.

Optionally, the calculating the ion strength according to the real mass molar concentration of each ion in the furnace water and the number of charges carried by each ion in the furnace water specifically includes:

and calculating the ion intensity according to the real mass molar concentration of each ion in the furnace water and the number of charges carried by each ion in the furnace water, wherein the calculation formula of the ion intensity is as follows:

wherein I represents the ionic strength and the unit mol kg^-1；m_iRepresents the true mass molar concentration of the i-th ion in mol. kg^-1；Z_iRepresents the number of charges of the i-th ion; n represents the number of types of ions in the furnace water.

Optionally, the calculating a constant coefficient according to the number of charges carried by ions in the furnace water, the dielectric constant of the solvent, the temperature of the furnace water, the viscosity of the solvent and the limiting molar conductivity of the ions specifically includes:

calculating a reduction value beta of the molar conductivity caused by the electrophoresis effect according to the number of charges carried by ions in the furnace water, the dielectric constant of the solvent, the temperature of the furnace water and the viscosity of the solvent, wherein the calculation formula of the reduction value beta is as follows:

wherein β represents the decrease in molar conductivity due to the electrophoretic effect, in units of S.m²·mol^-1η denotes the viscosity of the solvent in Pa s, D denotes the dielectric constant of the solvent in F/m, T denotes the temperature of the furnace water in K, and Z₁Indicates the number of charges of the first ion, Z₂Represents the number of charges of a second ion, the first ion and the second ionThe ions are two ions ionized by the same electrolyte in the furnace water;

obtaining an intermediate quantity q according to the limit molar conductivity of the ions and the number of charges carried by the ions, wherein the intermediate quantity q is calculated according to the following formula:

wherein q represents the intermediate quantity in the unit of S.m²·mol^-1；Z₁Represents the number of charges, Z, of the first ion₂Representing the charge number of the second ions, wherein the first ions and the second ions are two ions ionized by the same electrolyte in the furnace water;representing the limiting molar conductivity of said first ion,represents the limiting molar conductivity of the second ion;

calculating a reduction value alpha of the molar conductivity caused by the relaxation effect according to the number of charges carried by the ions, the intermediate quantity q, the dielectric constant of the solvent and the furnace water temperature, wherein the calculation formula of the reduction value alpha is as follows:

wherein α represents the decrease in molar conductivity due to relaxation effect, in units of S.m²·mol^-1(ii) a D represents the dielectric constant of the solvent, in F/m; t represents the furnace water temperature in K; z₁Represents the number of charges, Z, of the first ion₂Representing the number of charges carried by the second ions, the first ions and the second ions being ionized from the same electrolyte in the furnace waterTwo ions; q is the said intermediate quantity, in units of S.m²·mol^-1；

Calculating a first constant coefficient S according to the reduction value alpha, the reduction value beta and the ion limit molar conductivity, wherein the calculation formula of the first constant coefficient S is as follows:

S＝αλ_i ^∞+β (5)

wherein α represents the decrease in molar conductivity due to relaxation effect, in units of S.m²·mol^-1β shows the decrease in molar conductivity due to the electrophoretic effect, in units of S.m²·mol^-1；Represents the ultimate molar conductivity of the i-th ion in the furnace water in the unit of S.m²·mol^-1。

Optionally, the calculating a constant coefficient according to the number of charges carried by ions in the furnace water, the dielectric constant of the solvent, the temperature of the furnace water, the viscosity of the solvent, and the limiting molar conductivity of the ions further includes:

calculating a second constant coefficient E according to the number of charges carried by ions in the furnace water, the dielectric constant of the solvent, the temperature of the furnace water, the viscosity of the solvent and the ultimate molar conductivity of the ions, wherein the calculation process of the second constant coefficient E is as follows:

E＝E^(a)+E^(b)+E^(c)(9)

wherein E is^(a)、E^(b)、E^(c)Calculating an intermediate transition amount of the process for the second constant coefficient E, E being the second constant coefficient, D representing the dielectric constant of the solvent in F/m; t represents the furnace water temperature in K; z₁Represents the number of charges, Z, of the first ion₂Representing the charge number of the second ions, wherein the first ions and the second ions are two ions ionized by the same electrolyte in the furnace water; q is the said intermediate quantity, in units of S.m²·mol^-1；Represents the ultimate molar conductivity of the i-th ion in the furnace water in the unit of S.m²·mol^-1η represents the solvent viscosity in Pa · s;representing the limiting molar conductivity of said first ion,the limit molar conductivity of the second ion is shown, and the first ion and the second ion are two ions ionized by the same electrolyte in the furnace water.

Optionally, the calculating the molar conductivity of the strong electrolyte ions in the furnace water according to the ionic strength and the constant coefficient specifically includes:

calculating the molar conductivity of strong electrolyte ions in the furnace water according to the ionic strength and the constant coefficient, wherein the calculation formula of the molar conductivity of the strong electrolyte ions is as follows:

wherein λ is_iIndicating strong electrolyte in furnace waterMolar conductivity of the i-th ion electrolyzed in units S.m²·mol^-1；Represents the ultimate molar conductivity of the i-th ion in the furnace water in the unit of S.m²·mol^-1(ii) a S is the first constant coefficient, E is the second constant coefficient, and I represents the ionic strength.

Optionally, the calculating the molar conductivity of the weak electrolyte ions in the furnace water according to the limiting molar conductivity of the ions, the ionization degree of the weak electrolyte and the concentration of the weak electrolyte specifically includes:

calculating an intermediate coefficient A according to the limit molar conductivity of the ions, wherein the intermediate coefficient A is calculated according to the following formula:

wherein A is the intermediate coefficient; b is₁＝0.2300，B₂＝60.65，Represents the ultimate molar conductivity of the i-th ion in the furnace water in the unit of S.m²·mol^-1；

Calculating the molar conductivity of the weak electrolyte ions according to the limiting molar conductivity of the ions, the ionization degree of the weak electrolyte, the intermediate coefficient A and the weak electrolyte concentration, wherein the molar conductivity of the weak electrolyte ions is calculated according to the following formula:

wherein λ is_iRepresents the molar conductivity of the i-th ion electrolyzed from a weak electrolyte in the furnace water and has the unit of S.m²·mol^-1；Represents the ultimate molar conductivity of the i-th ion in the furnace water in the unit of S.m²·mol^-1(ii) a μ represents the ionization degree of the weak electrolyte; a represents the intermediate coefficient; c represents the concentration of weak electrolyte in mol/m³。

Optionally, the calculating the furnace water conductivity according to the molar conductivity of the strong electrolyte ions and the molar conductivity of the weak electrolyte ions specifically includes:

calculating the furnace water conductivity according to the molar conductivity of the strong electrolyte ions and the molar conductivity of the weak electrolyte ions, wherein the furnace water conductivity is calculated according to the following formula:

κ＝λ_iC (13)

wherein κ represents the furnace water conductivity in units of S · m^-1；λ_iRepresents the molar conductivity of the i-th ion electrolyzed by a strong electrolyte in the furnace water or the i-th ion electrolyzed by a weak electrolyte in the furnace water, and C represents the concentration of the i-th ion in mol/m³。

The invention also discloses a furnace water conductivity calculation system, which comprises:

the ion intensity calculation module is used for calculating the ion intensity according to the real mass molar concentration of each ion in the furnace water and the charge number of each ion in the furnace water;

the constant coefficient calculation module is used for calculating a constant coefficient according to the number of charges carried by ions in the furnace water, the dielectric constant of the solvent, the temperature of the furnace water, the viscosity of the solvent and the limit molar conductivity of the ions;

the strong electrolyte ion molar conductivity calculation module is used for calculating the molar conductivity of the strong electrolyte ions in the furnace water according to the ionic strength and the constant coefficient;

the weak electrolyte ion molar conductivity calculation module is used for calculating the molar conductivity of the weak electrolyte ions in the furnace water according to the limit molar conductivity of the ions, the ionization degree of the weak electrolyte and the concentration of the weak electrolyte;

and the furnace water conductivity calculation module is used for calculating the furnace water conductivity according to the molar conductivity of the strong electrolyte ions and the molar conductivity of the weak electrolyte ions.

Optionally, the ion intensity calculating module specifically includes:

the ion intensity calculation unit is used for calculating the ion intensity according to the real mass molar concentration of each ion in the furnace water and the number of charges carried by each ion in the furnace water, and the calculation formula of the ion intensity is as follows:

wherein I represents the ionic strength and the unit mol kg^-1；m_iRepresents the true mass molar concentration of the i-th ion in mol. kg^-1；Z_iRepresents the number of charges of the i-th ion; n represents the number of types of ions in the furnace water.

Optionally, the constant coefficient calculating module specifically includes:

a reduction value calculation unit for calculating a reduction value β of the molar conductivity caused by the electrophoresis effect based on the number of charges charged to the ions in the furnace water, the dielectric constant of the solvent, the temperature of the furnace water, and the viscosity of the solvent, wherein the calculation formula of the reduction value β is as follows:

wherein β represents the decrease in molar conductivity due to the electrophoretic effect, in units of S.m²·mol^-1η denotes the viscosity of the solvent in Pa.s, and D denotes the solventThe dielectric constant of (2), in units of F/m; t represents the furnace water temperature in K; z₁Indicates the number of charges of the first ion, Z₂Representing the charge number of a second ion, wherein the first ion and the second ion are two ions ionized by the same electrolyte in the furnace water;

an intermediate amount calculation unit for calculating an intermediate amount q from the limit molar conductivity of each ion in the furnace water and the number of charges charged to the ion, the intermediate amount q being calculated by the following formula:

wherein q represents the intermediate quantity in the unit of S.m²·mol^-1；Z₁Represents the number of charges, Z, of the first ion₂Representing the charge number of the second ions, wherein the first ions and the second ions are two ions ionized by the same electrolyte in the furnace water;representing the limiting molar conductivity of said first ion,represents the limiting molar conductivity of the second ion;

a drop value calculation unit for calculating a drop value α of the molar conductivity due to the relaxation effect based on the number of charges charged to the ions, the intermediate amount q, the dielectric constant of the solvent, and the furnace water temperature, the drop value α being calculated by the following formula:

wherein α represents the decrease in molar conductivity due to relaxation effect, in units of S.m²·mol^-1(ii) a D represents the dielectric constant of the solvent, in F/m; t represents the furnace water temperature in K; z₁Represents the number of charges, Z, of the first ion₂Representing the charge number of the second ions, wherein the first ions and the second ions are two ions ionized by the same electrolyte in the furnace water; q is the said intermediate quantity, in units of S.m²·mol^-1；

A first constant coefficient calculation unit, configured to calculate a first constant coefficient S according to the drop value α, the drop value β, and the ion limit molar conductivity, where the first constant coefficient S is calculated by the following formula:

S＝αλ_i ^∞+β (5)

wherein α represents the decrease in molar conductivity due to relaxation effect, in units of S.m²·mol^-1β shows the decrease in molar conductivity due to the electrophoretic effect, in units of S.m²·mol^-1；Represents the ultimate molar conductivity of the i-th ion in the furnace water in the unit of S.m²·mol^-1。

A second constant coefficient calculation unit, configured to calculate a second constant coefficient E according to the number of charges carried by each ion in the furnace water, the dielectric constant of the solvent, the temperature of the furnace water, the viscosity of the solvent, and the limiting molar conductivity of each ion, where the second constant coefficient E is calculated as follows:

E＝E^(a)+E^(b)+E^(c)(9)

wherein E is^(a)、E^(b)、E^(c)Representing the intermediate transition amount of the calculation process of the second constant coefficient E, wherein E represents the second constant coefficient, D represents the dielectric constant of the solvent and has the unit of F/m; t represents the furnace water temperature in K; z₁Represents the number of charges, Z, of the first ion₂Representing the charge number of the second ions, wherein the first ions and the second ions are two ions ionized by the same electrolyte in the furnace water; q is the said intermediate quantity, in units of S.m²·mol^-1；Represents the ultimate molar conductivity of the i-th ion in the furnace water in the unit of S.m²·mol^-1η represents the solvent viscosity in Pa · s;representing the limiting molar conductivity of said first ion,the limit molar conductivity of the second ions is shown, and the first ions and the second ions are two ions ionized by the same electrolyte in the furnace water

According to the specific embodiment provided by the invention, the invention discloses the following technical effects:

1. the method comprises the steps of firstly calculating the ionic strength according to the real mass molar concentration of each ion in furnace water and the charge number of each ion in the furnace water, then calculating a constant coefficient according to the charge number of the ion in the furnace water, the dielectric constant of a solvent, the temperature of the furnace water, the viscosity of the solvent and the limit molar conductivity of the ion, then calculating the molar conductivity of strong electrolyte ions in the furnace water according to the ionic strength and the constant coefficient, calculating the molar conductivity of weak electrolyte ions in the furnace water according to the limit molar conductivity of the ion, the ionization degree of the weak electrolyte and the concentration of the weak electrolyte, and finally calculating the conductivity of the furnace water according to the molar conductivity of the strong electrolyte ions and the molar conductivity of the weak electrolyte ions. According to the method and the system provided by the invention, the furnace water conductivity can be accurately calculated, so that a reference and an index are provided for monitoring the quality of the furnace water, judging the pollution discharge of the furnace water and assisting control of a multi-parameter cooperative automatic dosing control technology, and the numerical change of the furnace water conductivity can be accurately mastered, so that the quality of the furnace water quality is accurately reflected, and the safe operation of a boiler system of a thermal power plant is facilitated.

2. The method and the system provided by the invention can be suitable for the thermal power plant furnace water monitoring systems of different units, the calculation flow of the furnace water conductivity is simple, the calculation method is easy to popularize, the calculation efficiency is greatly improved, and the operation cost can be effectively reduced.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without inventive exercise.

FIG. 1 is a flow chart of a method of furnace water conductivity calculation according to an embodiment of the present invention;

FIG. 2 is a block diagram of a furnace water conductivity calculation system according to an embodiment of the present invention;

fig. 3 is a fitting graph of the conductivity of each system of the three alkalization agent mixed systems according to the embodiment of the invention and the concentration of the alkalization agent.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The invention aims to provide a furnace water conductivity calculation method and a furnace water conductivity calculation system.

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.

The system adds medicine in the boiler stove of power plant and divides into two parts:

1. feeding water and chemicals: the added drugs are typically ammonia and hydrazine. Ammonia is added to raise the feed water pH; hydrazine is used to remove dissolved oxygen from the water, and the two agents are added to the deaerator outlet pipe (not the deaerator) by a feedwater dosing pump.

2. Adding chemicals into furnace water. The added medicines are generally sodium phosphate and sodium hydroxide, and are used for increasing the pH value of furnace water. Phosphate and sodium hydroxide are added into a boiler steam drum through a boiler water dosing pump.

Both the feed water dosing and the boiler water dosing are for slowing down the corrosion of the boiler water vapor system. After the system is dosed, one or more of ammonia, sodium phosphate and sodium hydroxide are dissolved in the boiler water to form a boiler water solution. For convenience of description, the furnace water is furnace water solution dissolved with one or more solvents of ammonia, sodium phosphate and sodium hydroxide. Dissolving one or more of ammonia, sodium phosphate and sodium hydroxide in water to ionize OH^-、H⁺、Na⁺、And multiple ions, wherein the i-th ion is OH ionized by dissolving one or more of ammonia, sodium phosphate and sodium hydroxide in water^-、H⁺、Na⁺、One of a plurality of ions.

The pH value and the phosphate concentration are important indexes for controlling the water quality of boiler water, and when the boiler is not heated at first, no precipitate is formed in the boiler water, the hardness is low, and the quality is unchanged. Along with the increasing of the evaporation capacity of the boiler, the concentration of calcium and magnesium ions in the boiler water is increased continuously, and the electrical conductivity of the boiler water is increased. When the content of calcium and magnesium ions in the boiler water exceeds the solubility, partial calcium and magnesium ions are separated out and suspended and accumulated on the inner wall, dead corners, a header and the like of a boiler tube or attached to an evaporation heating surface of a boiler to form calcium and magnesium compound precipitates which are difficult to dissolve in water. In this case, the salt content and the precipitate in the furnace are usually reduced by adjusting the flow rates of the fixed row and the continuous row.

However, when the evaporation capacity of the boiler reaches a certain amount, it is uneconomical to control the conductivity or salt content of the boiler water only by fixed discharge and continuous discharge, and if the discharge capacity is too large, the steam-water circulation of the boiler is easily damaged, and the safe and stable operation of the boiler is influenced. At this time, in order to meet the requirements of the steam and water quality standards of the boiler, sodium phosphate which can remove calcium and magnesium ions and compounds is required to be added into the boiler discontinuously, hardness salts of the calcium and magnesium ions are converted into insoluble light water slag with strong liquidity, and the light water slag is discharged through a boiler fixed-discharge and continuous-discharge device. Na (Na)₃PO₄The chemical adding amount is adjusted according to the test result, after the chemical adding is carried out for a period of time, the quality of the tested steam is qualified, and the boiler operates normally, the chemical adding amount is continuously added, and the chemical adding amount is kept. To form light water slag without deposition all the time in the furnacePhosphate should be added to the alkaline furnace water, and a certain excess phosphate should be maintained in the furnace water, and the size of phosphate ions and the pH value in the furnace water should be monitored during operation.

Therefore, the pH value of the furnace water solution under various water working conditions is accurately calculated, and a reference and an index can be provided for the subsequent monitoring of the furnace water quality, the judgment of the furnace water pollution discharge and the auxiliary control of the multi-parameter cooperative automatic dosing control technology.

The invention provides a method for calculating the pH value of furnace water solution, which comprises the following steps of firstly calculating the H ion concentration in the furnace water according to the dosage of sodium phosphate, ammonia and sodium hydroxide in the furnace water, wherein the calculation formula is as follows:

-674.843-1.54719×10¹⁵x+1.68711×10¹²cx-2.80726×10²⁴x²+1.62734×10²⁴ax²+7.14539×10²¹bx²+3.86797×10²⁴cx²-4.3949×10³¹x³+2.9808×10³³ax³+1.6391×10³⁴bx³+7.01814×10³¹cx³+2.8072×10³⁸x⁴+9.28499×10⁴⁰ax⁴+2.59434×10⁴¹bx⁴+1.10259×10⁴¹cx⁴+4.41037×10⁴⁵x⁵+1.836×10⁴³ax⁵+3.42×1043bx⁵+1.4535×10⁴³cx⁵+5.814×10⁴⁷x⁶＝0 (14)

in the formula (14), a represents trisodium phosphate Na in furnace water₃PO₄The dosage of (1) is unit mg/L; b represents ammonia NH in the furnace water₃The dosage of (1) is unit mg/L; c represents the addition amount of NaOH in the furnace water, and the unit is mg/L; and x represents the hydrogen ion concentration in the furnace water to be solved, and the unit is mol/L.

Then, the pH value of the furnace water can be obtained according to the solved concentration of the hydrogen ions, and the calculation formula is as follows:

pH＝-lg[x](15)

in the formula (15), x represents the hydrogen ion concentration in the furnace water in mol/L.

Similarly, the conductivity of boiler water is an important indicator of boiler water quality control and is closely related to the pH value of boiler water. Therefore, the invention provides a method and a system for calculating the furnace water conductivity.

FIG. 1 is a flow chart of a method of an embodiment of the furnace water conductivity calculation method of the present invention.

A furnace water conductivity calculation method as shown in fig. 1, the method comprising:

step 101: calculating the ionic strength according to the real mass molar concentration of each ion in the furnace water and the charge number of each ion in the furnace water, and specifically comprises the following steps:

calculating the ion intensity according to the real mass molar concentration of each ion in the furnace water and the charge number of each ion in the furnace water, wherein the ion intensity I is defined as the mass molar concentration m of the ith ion in the furnace water solution_iMultiplied by the valence number Z of the ion_iHalf of the sum of the terms obtained by squaring, i.e. the ionic strength, is calculated as follows:

wherein I represents the ionic strength and the unit mol kg^-1；m_iRepresents the true mass molar concentration of the i-th ion in mol. kg^-1；Z_iRepresents the number of charges of the i-th ion; n represents the number of types of ions in the furnace water.

Step 102: calculating a constant coefficient according to the number of charges carried by ions in the furnace water, the dielectric constant of the solvent, the temperature of the furnace water, the viscosity of the solvent and the ultimate molar conductivity of the ions, and specifically comprising the following steps:

calculating a reduction value beta of the molar conductivity caused by the electrophoresis effect according to the number of charges carried by ions in the furnace water, the dielectric constant of the solvent, the temperature of the furnace water and the viscosity of the solvent, wherein the calculation formula of the reduction value beta is as follows:

wherein β represents the decrease in molar conductivity due to the electrophoretic effect, in units of S.m²·mol^-1η denotes the viscosity of the solvent in Pa s, D the dielectric constant of the solvent in F/m, in this example the dielectric constant of water, T the temperature of the furnace water in K, Z₁Indicates the number of charges of the first ion, Z₂Representing the charge number of a second ion, wherein the first ion and the second ion are two ions ionized by the same electrolyte in the furnace water;

obtaining an intermediate quantity q according to the limit molar conductivity of the ions and the number of charges carried by the ions, wherein the intermediate quantity q is calculated according to the following formula:

wherein q represents the intermediate quantity in the unit of S.m²·mol^-1；Z₁Represents the number of charges, Z, of the first ion₂Representing the charge number of the second ions, wherein the first ions and the second ions are two ions ionized by the same electrolyte in the furnace water;representing the limiting molar conductivity of said first ion,represents the limiting molar conductivity of the second ion;

calculating a reduction value alpha of the molar conductivity caused by the relaxation effect according to the number of charges carried by the ions, the intermediate quantity q, the dielectric constant of the solvent and the furnace water temperature, wherein the calculation formula of the reduction value alpha is as follows:

wherein α represents the decrease in molar conductivity due to relaxation effect, in units of S.m²·mol^-1(ii) a D represents the dielectric constant of the solvent, in F/m; t represents the furnace water temperature in K; z₁Represents the number of charges, Z, of the first ion₂Representing the charge number of the second ions, wherein the first ions and the second ions are two ions ionized by the same electrolyte in the furnace water; q is the said intermediate quantity, in units of S.m²·mol^-1；

Calculating a first constant coefficient S according to the reduction value alpha, the reduction value beta and the ion limit molar conductivity, wherein the calculation formula of the first constant coefficient S is as follows:

S＝αλ_i ^∞+β (5)

wherein α represents the decrease in molar conductivity due to relaxation effect, in units of S.m²·mol^-1β shows the decrease in molar conductivity due to the electrophoretic effect, in units of S.m²·mol^-1；Represents the ultimate molar conductivity of the i-th ion in the furnace water in the unit of S.m²·mol^-1。

The step 102 further comprises:

calculating a second constant coefficient E according to the number of charges carried by ions in the furnace water, the dielectric constant of the solvent, the temperature of the furnace water, the viscosity of the solvent and the ultimate molar conductivity of the ions, wherein the calculation process of the second constant coefficient E is as follows:

E＝E^(a)+E^(b)+E^(c)(9)

wherein E is^(a)、E^(b)、E^(c)Calculating an intermediate transition amount of the process for the second constant coefficient E, E being the second constant coefficient, D representing the dielectric constant of the solvent in F/m; t represents the furnace water temperature in K; z₁Represents the number of charges, Z, of the first ion₂Representing the charge number of the second ions, wherein the first ions and the second ions are two ions ionized by the same electrolyte in the furnace water; q is the said intermediate quantity, in units of S.m²·mol^-1；Represents the ultimate molar conductivity of the i-th ion in the furnace water in the unit of S.m²·mol^-1η represents the solvent viscosity in Pa · s;representing the limiting molar conductivity of said first ion,the limit molar conductivity of the second ion is shown, and the first ion and the second ion are two ions ionized by the same electrolyte in the furnace water.

Step 103: calculating the molar conductivity of strong electrolyte ions in the furnace water according to the ionic strength and the constant coefficient, and specifically comprises the following steps:

calculating the molar conductivity of strong electrolyte ions in the furnace water according to the ionic strength and the constant coefficient, wherein the calculation formula of the molar conductivity of the strong electrolyte ions is as follows:

wherein λ is_iRepresents the molar conductivity of the i-th ion electrolyzed from a strong electrolyte in the furnace water, with the unit of S.m²·mol^-1；Represents the ultimate molar conductivity of the i-th ion in the furnace water in the unit of S.m²·mol^-1(ii) a S is the first constant coefficient, E is the second constant coefficient, and I represents the ionic strength.

Step 104: calculating the molar conductivity of weak electrolyte ions in the furnace water according to the limiting molar conductivity of the ions, the ionization degree of the weak electrolyte and the concentration of the weak electrolyte, and specifically comprising the following steps:

calculating an intermediate coefficient A according to the limit molar conductivity of the ions, wherein the intermediate coefficient A is calculated according to the following formula:

wherein A is the intermediate coefficient; at 298K, when water is used as solvent for 1-1 type electrolyte, B₁＝0.2300，B₂＝60.65；Represents the ultimate molar conductivity of the i-th ion in the furnace water in the unit of S.m²·mol^-1；

Calculating the molar conductivity of the weak electrolyte ions according to the limiting molar conductivity of the ions, the ionization degree of the weak electrolyte, the intermediate coefficient A and the weak electrolyte concentration, wherein the molar conductivity of the weak electrolyte ions is calculated according to the following formula:

wherein λ is_iRepresents the molar conductivity of the i-th ion electrolyzed from a weak electrolyte in the furnace water and has the unit of S.m²·mol^-1；Represents the ultimate molar conductivity of the i-th ion in the furnace water in the unit of S.m²·mol^-1(ii) a μ represents the ionization degree of the weak electrolyte; a represents the intermediate coefficient; c represents the concentration of weak electrolyte in mol/m³。

It is to be noted that sodium phosphate and sodium hydroxide are strong electrolytes, and the above formula (10) is employed when calculating the molar conductivity of strong electrolyte ions electrolyzed from sodium phosphate and sodium hydroxide in the furnace water, and the above formula (12) is employed when calculating the molar conductivity of weak electrolyte ions in the furnace water, for example, the molar conductivity of ions in ammonia water.

Step 105: calculating the furnace water conductivity according to the molar conductivity of the strong electrolyte ions and the molar conductivity of the weak electrolyte ions, and specifically comprising the following steps:

calculating the furnace water conductivity according to the molar conductivity of the strong electrolyte ions and the molar conductivity of the weak electrolyte ions, wherein the furnace water conductivity is calculated according to the following formula:

κ＝λ_iC (13)

wherein κ represents the furnace water conductivity in units of S · m^-1；λ_iIndicating the molar conductivity of the i-th ion electrolyzed from a strong electrolyte in the furnace water or the weak electrolyte in the furnace waterThe molar conductivity of the i-th ion electrolyzed, C represents the concentration of the i-th ion in mol/m³。

For the mixed furnace aqueous solutions of multiple electrolytes, the furnace water conductivities of the mixed electrolyte furnace aqueous solutions can be obtained by calculating the furnace water conductivity of each electrolyte furnace aqueous solution and then adding up.

FIG. 2 is a system configuration diagram of an embodiment of the furnace water conductivity calculation system of the present invention.

Referring to fig. 2, a furnace water conductivity calculation system, the system comprising:

an ion intensity calculation module 201, configured to calculate an ion intensity according to a real mass molar concentration of each ion in the furnace water and a charge number of each ion in the furnace water;

a constant coefficient calculation module 202, configured to calculate a constant coefficient according to the number of charges carried by ions in the furnace water, the dielectric constant of the solvent, the temperature of the furnace water, the viscosity of the solvent, and the limiting molar conductivity of the ions;

the strong electrolyte ion molar conductivity calculation module 203 is used for calculating the molar conductivity of the strong electrolyte ions in the furnace water according to the ionic strength and the constant coefficient;

the weak electrolyte ion molar conductivity calculation module 204 is used for calculating the molar conductivity of the weak electrolyte ions in the furnace water according to the limit molar conductivity of the ions, the ionization degree of the weak electrolyte and the concentration of the weak electrolyte;

a furnace water conductivity calculation module 205 for calculating the furnace water conductivity based on the molar conductivity of the strong electrolyte ions and the molar conductivity of the weak electrolyte ions.

The ion intensity calculating module 201 specifically includes:

the ion intensity calculation unit is used for calculating the ion intensity according to the real mass molar concentration of each ion in the furnace water and the number of charges carried by each ion in the furnace water, and the calculation formula of the ion intensity is as follows:

wherein I represents the ionic strength and the unit mol kg^-1；m_iRepresents the true mass molar concentration of the i-th ion in mol. kg^-1；Z_iRepresents the number of charges of the i-th ion; n represents the number of types of ions in the furnace water.

The constant coefficient calculation module 202 specifically includes:

a reduction value calculation unit for calculating a reduction value beta of the molar conductivity caused by the electrophoresis effect according to the number of charges carried by the ions in the furnace water, the dielectric constant of the solvent, the temperature of the furnace water and the viscosity of the solvent, wherein the calculation formula of the reduction value beta is as follows:

wherein β represents the decrease in molar conductivity due to the electrophoretic effect, in units of S.m²·mol^-1η denotes the viscosity of the solvent in Pa s, D denotes the dielectric constant of the solvent in F/m, T denotes the temperature of the furnace water in K, and Z₁Indicates the number of charges of the first ion, Z₂And the number of charges carried by second ions is shown, and the first ions and the second ions are two ions ionized by the same electrolyte in the furnace water.

An intermediate quantity calculating unit, which is used for calculating an intermediate quantity q according to the limit molar conductivity of the ions and the number of charges carried by the ions, and the calculation formula of the intermediate quantity q is as follows:

wherein q represents the intermediate quantity in the unit of S.m²·mol^-1；Z₁Represents the number of charges, Z, of the first ion₂Representing the charge number of the second ions, wherein the first ions and the second ions are two ions ionized by the same electrolyte in the furnace water;representing the limiting molar conductivity of said first ion,representing the limiting molar conductivity of the second ion.

A drop value calculation unit for calculating a drop value α of the molar conductivity due to the relaxation effect from the number of charges charged to the ions, the intermediate amount q, the dielectric constant of the solvent, and the furnace water temperature, the drop value α being calculated by the following formula:

wherein α represents the decrease in molar conductivity due to relaxation effect, in units of S.m²·mol^-1(ii) a D represents the dielectric constant of the solvent, in F/m; t represents the furnace water temperature in K; z₁Represents the number of charges, Z, of the first ion₂Representing the charge number of the second ions, wherein the first ions and the second ions are two ions ionized by the same electrolyte in the furnace water; q is the said intermediate quantity, in units of S.m²·mol^-1；

A first constant coefficient calculation unit, configured to calculate a first constant coefficient S according to the drop value α, the drop value β, and the ion limit molar conductivity, where the first constant coefficient S is calculated by the following formula:

S＝αλ_i ^∞+β (5)

wherein α represents the decrease in molar conductivity due to relaxation effect, in units of S.m²·mol^-1β shows the decrease in molar conductivity due to the electrophoretic effect, in units of S.m²·mol^-1；Represents the ultimate molar conductivity of the i-th ion in the furnace water in the unit of S.m²·mol^-1。

The constant coefficient calculation module 202 further includes:

a second constant coefficient calculation unit, configured to calculate a second constant coefficient E according to the number of charges carried by ions in the furnace water, the dielectric constant of the solvent, the temperature of the furnace water, the viscosity of the solvent, and the limiting molar conductivity of the ions, where the second constant coefficient E is calculated as follows:

E＝E^(a)+E^(b)+E^(c)(9)

wherein E is^(a)、E^(b)、E^(c)Calculating an intermediate transition amount of the process for the second constant coefficient E, E being the second constant coefficient, D representing the dielectric constant of the solvent in F/m; t represents the furnace water temperature in K; z₁Represents the number of charges, Z, of the first ion₂Representing the number of charges carried by the second ions, the first ions and the second ions being ionized by the same electrolyte in the furnace waterTwo kinds of ions are generated; q is the said intermediate quantity, in units of S.m²·mol^-1；Represents the ultimate molar conductivity of the i-th ion in the furnace water in the unit of S.m²·mol^-1η represents the solvent viscosity in Pa · s;representing the limiting molar conductivity of said first ion,the limit molar conductivity of the second ion is shown, and the first ion and the second ion are two ions ionized by the same electrolyte in the furnace water.

The strong electrolyte ion molar conductivity calculation module 203 specifically includes:

the strong electrolyte ion molar conductivity calculation unit is used for calculating the molar conductivity of the strong electrolyte ions in the furnace water according to the ionic strength and the constant coefficient, and the calculation formula of the molar conductivity of the strong electrolyte ions is as follows:

wherein λ is_iRepresents the molar conductivity of the i-th ion electrolyzed from a strong electrolyte in the furnace water, with the unit of S.m²·mol^-1；Represents the ultimate molar conductivity of the i-th ion in the furnace water in the unit of S.m²·mol^-1(ii) a S is the first constant coefficient, E is the second constant coefficient, and I represents the ionic strength.

The weak electrolyte ion molar conductivity calculation module 204 specifically includes:

the intermediate coefficient calculation unit is used for calculating an intermediate coefficient A according to the limit molar conductivity of the ions, and the calculation formula of the intermediate coefficient A is as follows:

wherein A is the intermediate coefficient; b is₁＝0.2300，B₂＝60.65，Represents the ultimate molar conductivity of the i-th ion in the furnace water in the unit of S.m²·mol^-1；

A weak electrolyte ion molar conductivity calculation unit, configured to calculate a molar conductivity of the weak electrolyte ion according to the limiting molar conductivity of the ion, the ionization degree of the weak electrolyte, the intermediate coefficient a, and the weak electrolyte concentration, wherein the molar conductivity of the weak electrolyte ion is calculated according to the following formula:

wherein λ is_iRepresents the molar conductivity of the i-th ion electrolyzed from a weak electrolyte in the furnace water and has the unit of S.m²·mol^-1；Represents the ultimate molar conductivity of the i-th ion in the furnace water in the unit of S.m²·mol^-1(ii) a μ represents the ionization degree of the weak electrolyte; a represents the intermediate coefficient; c represents the concentration of weak electrolyte in mol/m³。

Optionally, the furnace water conductivity calculation module 205 specifically includes:

a furnace water conductivity calculation unit, configured to calculate a furnace water conductivity according to the molar conductivity of the strong electrolyte ions and the molar conductivity of the weak electrolyte ions, where the furnace water conductivity is calculated according to the following formula:

κ＝λ_iC (13)

wherein κ represents the furnace water conductivity in units of S · m^-1；λ_iRepresents the molar conductivity of the i-th ion electrolyzed by a strong electrolyte in the furnace water or the i-th ion electrolyzed by a weak electrolyte in the furnace water, and C represents the concentration of the i-th ion in mol/m³。

The invention establishes a model for theoretical calculation of the furnace water conductivity, which comprises calculation of the pH value of the furnace water solution and theoretical calculation of the furnace water conductivity, can accurately reflect the quality of the furnace water quality, and is beneficial to the safe operation of a boiler system of a thermal power plant. The establishment of the conductivity calculation model and the application of the conductivity calculation model in the automatic dosing system of the thermal power plant can accurately calculate the conductivity of a complex mixing system, and provide a reference and index for monitoring the quality of furnace water, judging the pollution discharge of the furnace water and auxiliary control of a multi-parameter cooperative automatic dosing control technology. Compared with the prior art, the method highlights the accurate calculation of the conductivity of the complex mixed system, the conductivity is used as an important index of the water quality, and the quality of the furnace water quality can be reflected by accurately mastering the numerical change of the conductivity. The method for calculating the pH value of the furnace water solution and the method for calculating the conductivity of the furnace water provided by the invention can be suitable for furnace water monitoring systems of thermal power plants of different units, the conductivity calculation flow is simple, the calculation method is easy to popularize, the operation efficiency is greatly improved, and the operation cost can be effectively reduced.

The method of the present invention is further described below with reference to specific examples, which are intended to illustrate the method of the present invention and not to limit the scope of the invention.

Example 1: and (4) theoretical calculation of the conductivity of the furnace water alkalizer.

In pure phosphate treatment, the calculation is complicated by the high tendency of phosphate ions to hydrolyze. Na (Na)₃PO₄Produced by complete ionisationOH generation after hydrolysis^-Its hydrolysis and ionization reactions in the furnace water are as follows:

tertiary hydrolysis will occur:

as can be seen from the above hydrolysis constants, the secondary hydrolysis and the tertiary hydrolysis are completely negligible compared to the primary hydrolysis, plus the furnace waterSo that Na can be added when the furnace water conductivity is calculated₃PO₄Treated as a strong monobasic base.

According to the dosage of the sodium phosphate, the pH value of the furnace water under corresponding conditions and the concentration of each ion can be calculated, and according to the formula (1), the pH value and the concentration of each ion can be calculatedTo the ionic strength of the system. Due to Na₃PO₄Can be regarded as a monobasic strong base, and therefore, Na can be calculated by the formula (10)₃PO₄Molar conductivity of (a):

wherein,indicating the water content of the furnace is Na₃PO₄Molar conductivity of the i-th ion electrolyzed in units S.m²·mol^-1；Indicating the water content of the furnace is Na₃PO₄Ultimate molar conductivity of the electrolyzed i-th ion in units of S.m²·mol^-1(ii) a S is a first constant coefficient, E is a second constant coefficient, and I represents the ionic strength.

By bringing into constants of various terms to obtain Na₃PO₄Molar conductivity ofThus obtaining the furnace water conductivity when pure trisodium phosphate is treated.

The pure sodium hydroxide treatment is also called CT water working condition treatment, and the working condition is simpler, and is 1-1 type strong electrolyte dilute solution and pure Na₃PO₄The calculation process of the treatment system is similar, and various constants are introduced to obtain the molar conductivity of the aqueous solution of the NaOH furnace:

thus obtaining the furnace water conductivity when the pure sodium hydroxide is treated.

Ammonia, unlike sodium hydroxide solutions and trisodium phosphate solutions, is an associative weak electrolyte that does not ionize completely in water. Therefore, the degree of ionization of ammonia is taken into account in calculating the conductivity of the furnace water under such conditions.

If the dosage of the ammonia in the furnace water is b mg/L, the molar concentration c of the ammonia is a/17mol/L, and the dissociation constant K of the ammonia is 1.8 × 10^-5And the ionization degree is mu, the following are:

after obtaining the degree of ionization, the NH can be calculated using equation (12)₃H₂Furnace water molar conductivity of O:

wherein,

the conductivity of the furnace water during the treatment of the pure ammonia water with corresponding concentration can be calculated.

Example 2: the application of the furnace water conductivity calculation model in a three-alkalizer mixing system.

Instruments and reagents

The reagents used in the experiment are superior pure NaOH and analytically pure Na₃PO₄Analytically pure formaldehyde solution, sulfuric acid solution, analytically pure NH₃H₂O, a molybdovanadic acid color development solution, a 1% phenolphthalein indicator (ethanol solution), potassium hydrogen phthalate and a potassium dihydrogen phosphate standard solution (1 mg/mL).

The instrument mainly comprises a plurality of volumetric flasks with different volumes, small beakers, reagent bottles, weighing bottles, basic burettes, pipettes with different models, analytical balances, electronic balances, tray balances, a DDS-11A conductivity meter, a CS-501-3C constant-temperature water bath, a PHS-3C acidity meter, a 721 type spectrophotometer, a 70 type ion exchange water purifier and the like.

Preparation of three alkalizer standard solutions:

1) preparation of sodium hydroxide standard solution

Preparing 0.05mol/L sodium hydroxide solution, wherein the preparation steps are as follows:

A. weighing 2g of a sodium hydroxide sample of high-grade purity in a beaker, dissolving the sodium hydroxide sample with demineralized water, transferring the dissolved sodium hydroxide sample into a volumetric flask of one liter, and diluting the sodium hydroxide sample to a scale;

B. weighing about 1g of potassium hydrogen phthalate in a dried weighing bottle, weighing 3 parts of 0.2-0.3g of potassium hydrogen phthalate in parallel by a subtraction method, and respectively dissolving;

C. 3 drops of phenolphthalein indicator were added separately and titrated to a stable reddish shade with a crude NaOH solution.

2) Preparation of ammonia water standard solution

Preparing 500mg/L ammonia water solution, measuring the ammonia concentration by a volumetric method, and preparing the following steps:

A. transferring 50.0mL of prepared ammonia solution, injecting into a 250mL conical flask, adding 1-2 drops of 1% phenolphthalein indicator to make the solution show purple red, titrating with 0.025mol/L sulfuric acid solution until the red color just disappears, and titrating with standard solution NaOH to show stable reddish color;

B. adding the prepared formaldehyde solution, shaking up, reacting for a period of time, adding a phenolphthalein indicator, and titrating with standard solution NaOH until the solution is in a stable reddish color;

C. two more parallel experiments were performed as above.

3) Preparation of trisodium phosphate standard solution

A. Taking 10.00mL to 100mL volumetric flask of 1.0mg/mL monopotassium phosphate standard solution, and adding desalted water to dilute to a scale;

B. accurately weighing 1.1830g of analytically pure trisodium phosphate sample, adding desalted water for dissolving, and diluting to 500 mL;

C. preparing a molybdenum vanadate developing solution: weighing 50g of ammonium molybdate and 2.5g of ammonium metavanadate, dissolving the ammonium molybdate and the ammonium metavanadate in 400mL of desalted water, weighing 195mL of concentrated sulfuric acid by using a measuring cylinder, slowly adding the concentrated sulfuric acid into 250mL of desalted water, cooling to room temperature, and pouring the solution into the solution prepared in the step A;

D. drawing a working curve;

E. diluting 1.25mL of roughly prepared trisodium phosphate solution to 250mL, adding 5mL of molybdovanadate chromogenic solution into 50.00mL of test solution, shaking up, standing for 2 minutes, and measuring the absorbance under the same condition;

F. the concentration of the sample is found from the working curve.

In summary, all the standard stock solutions were prepared with ultrapure water having a resistivity of 18.25 M.OMEGA.cm, and stored in polyethylene bottles at 0-4 ℃.

Calculating the furnace water conductivity of the three alkalizers mixed system:

and under the specific NaOH concentration (0.4mg/L) and trisodium phosphate concentration and a series of concentration gradient ammonia water concentrations (0.1, 0.3, 0.5, 0.8 and 1.0mg/L), obtaining a theoretical conductivity value by using a furnace water conductivity calculation model, fitting with a laboratory simulation value to obtain a linear relation between the furnace water conductivity theoretical value and an alkalizer, and providing a theoretical basis for the application of an automatic dosing system.

Under the concentration of 5 concentration gradient ammonia water, the calculation result of the linear relation between the conductivity value and the alkalizer obtained by the furnace water conductivity calculation method is as follows:

1) under the concentration of 0.1mg/L ammonia water, the linear relation is that Y is 2.766+2.876 xX, wherein Y is the conductivity, and X is the concentration of an alkalizer;

2) under the concentration of 0.3mg/L ammonia water, the linear relation is that Y is 4.63+2.980 XX, wherein, Y is the conductivity, and X is the concentration of the alkalizer;

3) under the concentration of 0.5mg/L ammonia water, the linear relation is that Y is 6.235+2.758 xX, wherein, Y is the conductivity, and X is the concentration of the alkalizer;

4) under the concentration of 0.8mg/L ammonia water, the linear relation is that Y is 8.20+2.680 XX, wherein, Y is the conductivity, and X is the concentration of the alkalizer;

5) the linear relationship is that Y is 9.28+2.60 XX under the concentration of 1.0mg/L ammonia water, wherein Y is the conductivity, and X is the concentration of the alkalizer.

For a system in which three alkalizers are mixed, a furnace water conductivity calculation model obtains a theoretical conductivity value, the theoretical conductivity value is fitted with a laboratory simulation value, a relational expression of the conductivity of each system and the concentration of the alkalizers is obtained, and a fitting graph shown in the attached figure 3 of the specification is also obtained.

In conclusion, when the three alkalizers are mixed, the conductivity change regularity of the furnace water is strongest, and the correlation coefficient is higher. The furnace water conductivity calculation model method established by the invention can be effectively applied to an automatic dosing system of a thermal power plant, can accurately calculate the conductivity of a complex mixing system, obtains the linear relation, and can provide a theoretical basis for controlling the dosing quantity of the dosing system. The invention provides a reference and index for monitoring the quality of the boiler water, judging the pollution discharge of the boiler water and assisting the control of the multi-parameter cooperative automatic dosing control technology, and is beneficial to the safe and economic operation of the boiler system of the thermal power plant.

The principles and embodiments of the present invention have been described herein using specific examples, which are provided only to help understand the method and the core concept of the present invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In view of the above, the present disclosure should not be construed as limiting the invention.

Claims (10)

1. A method of calculating furnace water conductivity, the method comprising:

calculating the ionic strength according to the real mass molar concentration of each ion in the furnace water and the charge number of each ion in the furnace water;

calculating a constant coefficient according to the number of charges carried by each ion in the furnace water, the dielectric constant of the solvent, the temperature of the furnace water, the viscosity of the solvent and the limit molar conductivity of each ion;

calculating the molar conductivity of strong electrolyte ions in the furnace water according to the ionic strength and the constant coefficient;

calculating the molar conductivity of weak electrolyte ions in the furnace water according to the limit molar conductivity of each ion, the ionization degree of the weak electrolyte and the concentration of the weak electrolyte;

and calculating the furnace water conductivity according to the molar conductivity of the strong electrolyte ions and the molar conductivity of the weak electrolyte ions.

2. The method of claim 1, wherein calculating the ionic strength based on the actual molarity of each ion in the furnace water and the number of charges carried by each ion in the furnace water comprises:

and calculating the ion intensity according to the real mass molar concentration of each ion in the furnace water and the number of charges carried by each ion in the furnace water, wherein the calculation formula of the ion intensity is as follows:

$I=\frac{1}{2}\underset{1}{\overset{n}{\Σ}}{m}_i{Z}_i^2---\left(1\right)$

wherein I represents the ionic strength and the unit mol kg^-1；m_iRepresents the real mass molar concentration of the ith ion in the furnace water in mol kg^-1；Z_iRepresents the number of charges of the i-th ion; n represents the number of types of ions in the furnace water.

3. The method of claim 2, wherein calculating the constant coefficient based on the number of charges of each ion in the furnace water, the dielectric constant of the solvent, the temperature of the furnace water, the viscosity of the solvent, and the limiting molar conductivity of each ion comprises:

calculating a reduction value beta of the molar conductivity caused by the electrophoresis effect according to the number of charges carried by each ion in the furnace water, the dielectric constant of the solvent, the temperature of the furnace water and the viscosity of the solvent, wherein the calculation formula of the reduction value beta is as follows:

$\mathrm{\β}=\frac{41.24}{\mathrm{\η}{\left(DT\right)}^{1/2}}\left(\right|Z_1|+|Z_2\left|\right)---\left(2\right)$

wherein β represents the decrease in molar conductivity due to the electrophoretic effect, in units of S.m²·mol^-1η denotes the viscosity of the solvent in Pa s, D denotes the dielectric constant of the solvent in F/m, T denotes the temperature of the furnace water in K, and Z₁Indicates the number of charges of the first ion, Z₂Representing the charge number of a second ion, wherein the first ion and the second ion are two ions ionized by the same electrolyte in the furnace water;

obtaining an intermediate quantity q according to the limit molar conductivity of each ion in the furnace water and the number of charges carried by the ions, wherein the intermediate quantity q is calculated by the following formula:

$q=\frac{\left|Z_1{Z}_2\right|({\mathrm{\λ}}_1^{\mathrm{\∞}}+{\mathrm{\λ}}_2^{\mathrm{\∞}})}{\left(\right|Z_1|+|Z_2\left|\right)\left(\right|Z_1|{\mathrm{\λ}}_2^{\mathrm{\∞}}+|Z_2\left|{\mathrm{\λ}}_1^{\mathrm{\∞}}\right)}---\left(3\right)$

wherein q represents the intermediate quantity in the unit of S.m²·mol^-1；Z₁Represents the number of charges, Z, of the first ion₂Representing the charge number of the second ions, wherein the first ions and the second ions are two ions ionized by the same electrolyte in the furnace water;representing the limiting molar conductivity of said first ion,indicating said second type of separationThe limiting molar conductivity of the daughter;

calculating a reduction value alpha of the molar conductivity caused by the relaxation effect according to the number of charges carried by each ion, the intermediate quantity q, the dielectric constant of the solvent and the furnace water temperature, wherein the calculation formula of the reduction value alpha is as follows:

$\mathrm{\α}=\frac{2.801\×{10}^6}{{\left(DT\right)}^{3/2}}\left|Z_1{Z}_2\right|\frac{q}{1+\sqrt{q}}---\left(4\right)$

wherein α represents the decrease in molar conductivity due to relaxation effect, in units of S.m²·mol^-1(ii) a D represents the dielectric constant of the solvent, in F/m; t represents the furnace water temperature in K; z₁Represents the number of charges, Z, of the first ion₂Representing the charge number of the second ions, wherein the first ions and the second ions are two ions ionized by the same electrolyte in the furnace water; q is the said intermediate quantity, in units of S.m²·mol^-1；

Calculating a first constant coefficient S according to the reduction value alpha, the reduction value beta and the ion limit molar conductivity, wherein the calculation formula of the first constant coefficient S is as follows:

S＝αλ_i ^∞+β (5)

wherein α represents the decrease in molar conductivity due to relaxation effect, in units of S.m²·mol^-1β shows the decrease in molar conductivity due to the electrophoretic effect, in units of S.m²·mol^-1；Represents the ultimate molar conductivity of the i-th ion in the furnace water in the unit of S.m²·mol^-1。

4. The method of claim 3, wherein said calculating constant coefficients from the number of charges of said ions in the furnace water, the dielectric constant of the solvent, the temperature of the furnace water, the viscosity of the solvent, and the limiting molar conductivity of said ions further comprises:

calculating a second constant coefficient E according to the number of charges of each ion in the furnace water, the dielectric constant of the solvent, the temperature of the furnace water, the viscosity of the solvent and the limit molar conductivity of each ion, wherein the calculation process of the second constant coefficient E is as follows:

$E^{\left(a\right)}=\frac{5.885\×{10}^{12}}{{\left(DT\right)}^3}{\left(Z_1{Z}_2\right)}^2{\mathrm{q\λ}}_i^{\mathrm{\∞}}---\left(6\right)$

$E^{\left(b\right)}=-\frac{4.332\×{10}^7}{\mathrm{\η}{\left(DT\right)}^2}\left(\right|Z_1|+|Z_2\left|\right){(Z_1+Z_2)}^3---\left(7\right)$

$E^{\left(c\right)}=-\frac{8.665\×{10}^7}{\mathrm{\η}{\left(DT\right)}^2}\frac{\left(Z_1^4+Z_2^4\right)}{2\left(\left|Z_1\right|+\left|Z_2\right|\right)}+\left|Z_1{Z}_2\right|q\frac{\left|Z_1\right|{\mathrm{\λ}}_1^{\mathrm{\∞}}+\left|Z_2\right|{\mathrm{\λ}}_2^{\mathrm{\∞}}}{{\mathrm{\λ}}_i^{\mathrm{\∞}}}---\left(8\right)$

E＝E^(a)+E^(b)+E^(c)(9)

wherein E is^(a)、E^(b)、E^(c)Indicating that the second constant coefficient E has been calculatedThe intermediate transition amount of the equation, E represents the second constant coefficient, D represents the dielectric constant of the solvent, and the unit is F/m; t represents the furnace water temperature in K; z₁Represents the number of charges, Z, of the first ion₂Representing the charge number of the second ions, wherein the first ions and the second ions are two ions ionized by the same electrolyte in the furnace water; q is the said intermediate quantity, in units of S.m²·mol^-1；Represents the ultimate molar conductivity of the i-th ion in the furnace water in the unit of S.m²·mol^-1η represents the solvent viscosity in Pa · s;representing the limiting molar conductivity of said first ion,the limit molar conductivity of the second ion is shown, and the first ion and the second ion are two ions ionized by the same electrolyte in the furnace water.

5. The method according to claim 4, wherein the calculating the molar conductivity of strong electrolyte ions in the furnace water according to the ionic strength and the constant coefficient specifically comprises:

calculating the molar conductivity of strong electrolyte ions in the furnace water according to the ionic strength and the constant coefficient, wherein the calculation formula of the molar conductivity of the strong electrolyte ions is as follows:

${\mathrm{\λ}}_i={\mathrm{\λ}}_i^{\mathrm{\∞}}-S\sqrt{I}+EI\ln I---\left(10\right)$

wherein λ is_iRepresents the molar conductivity of the i-th ion electrolyzed from a strong electrolyte in the furnace water, with the unit of S.m²·mol^-1；Represents the ultimate molar conductivity of the i-th ion in the furnace water in the unit of S.m²·mol^-1(ii) a S is the first constant coefficient, E is the second constant coefficient, and I represents the ionic strength.

6. The method of claim 5, wherein calculating the molar conductivity of the weak electrolyte ions in the furnace water based on the limiting molar conductivity of each ion, the ionization degree of the weak electrolyte, and the weak electrolyte concentration comprises:

calculating an intermediate coefficient A according to the limit molar conductivity of each ion, wherein the calculation formula of the intermediate coefficient A is as follows:

$A=B_1+B_2/{\mathrm{\λ}}_i^{\mathrm{\∞}}---\left(11\right)$

wherein A is the intermediate coefficient; b is₁＝0.2300，B₂＝60.65，Represents the ultimate molar conductivity of the i-th ion in the furnace water in the unit of S.m²·mol^-1；

Calculating the molar conductivity of the weak electrolyte ions according to the limiting molar conductivity of the ions, the ionization degree of the weak electrolyte, the intermediate coefficient A and the weak electrolyte concentration, wherein the molar conductivity of the weak electrolyte ions is calculated according to the following formula:

${\mathrm{\λ}}_i={\mathrm{\λ}}_i^{\mathrm{\∞}}{\mathrm{\μe}}^{-A\sqrt{c\mathrm{\μ}}}---\left(12\right)$

wherein λ is_iRepresents the molar conductivity of the i-th ion electrolyzed from a weak electrolyte in the furnace water and has the unit of S.m²·mol^-1；Represents the ultimate molar conductivity of the i-th ion in the furnace water in the unit of S.m²·mol^-1(ii) a μ represents the ionization degree of the weak electrolyte; a represents the intermediate coefficient; c represents the concentration of weak electrolyte in mol/m³。

7. The method of claim 6, wherein calculating the furnace water conductivity from the molar conductivity of the strong electrolyte ions and the molar conductivity of the weak electrolyte ions comprises:

calculating the furnace water conductivity according to the molar conductivity of the strong electrolyte ions and the molar conductivity of the weak electrolyte ions, wherein the furnace water conductivity is calculated according to the following formula:

κ＝λ_iC (13)

wherein κ represents the furnace waterConductivity, unit S.m^-1；λ_iRepresents the molar conductivity of the i-th ion electrolyzed by a strong electrolyte in the furnace water or the i-th ion electrolyzed by a weak electrolyte in the furnace water, and C represents the concentration of the i-th ion in mol/m³。

8. A furnace water conductivity calculation system, the system comprising:

the ion intensity calculation module is used for calculating the ion intensity according to the real mass molar concentration of each ion in the furnace water and the charge number of each ion in the furnace water;

the constant coefficient calculation module is used for calculating a constant coefficient according to the number of charges carried by ions in the furnace water, the dielectric constant of the solvent, the temperature of the furnace water, the viscosity of the solvent and the limit molar conductivity of the ions;

the strong electrolyte ion molar conductivity calculation module is used for calculating the molar conductivity of the strong electrolyte ions in the furnace water according to the ionic strength and the constant coefficient;

the weak electrolyte ion molar conductivity calculation module is used for calculating the molar conductivity of the weak electrolyte ions in the furnace water according to the limit molar conductivity of the ions, the ionization degree of the weak electrolyte and the concentration of the weak electrolyte;

and the furnace water conductivity calculation module is used for calculating the furnace water conductivity according to the molar conductivity of the strong electrolyte ions and the molar conductivity of the weak electrolyte ions.

9. The system of claim 8, wherein the ion intensity calculation module specifically comprises:

the ion intensity calculation unit is used for calculating the ion intensity according to the real mass molar concentration of each ion in the furnace water and the number of charges carried by each ion in the furnace water, and the calculation formula of the ion intensity is as follows:

$I=\frac{1}{2}\underset{1}{\overset{n}{\Σ}}{m}_i{Z}_i^2---\left(1\right)$

wherein I represents the ionic strength and the unit mol kg^-1；m_iRepresents the true mass molar concentration of the i-th ion in mol. kg^-1；Z_iRepresents the number of charges of the i-th ion; n represents the number of types of ions in the furnace water.

10. The system of claim 8, wherein the constant coefficient calculation module specifically comprises:

a reduction value calculation unit for calculating a reduction value β of the molar conductivity caused by the electrophoresis effect based on the number of charges charged to the ions in the furnace water, the dielectric constant of the solvent, the temperature of the furnace water, and the viscosity of the solvent, wherein the calculation formula of the reduction value β is as follows:

$\mathrm{\β}=\frac{41.24}{\mathrm{\η}{\left(DT\right)}^{1/2}}\left(\right|Z_1|+|Z_2\left|\right)---\left(2\right)$

wherein β denotes the electrophoresis effectDecrease in molar conductivity of (1), unit S.m²·mol^-1η denotes the viscosity of the solvent in Pa s, D denotes the dielectric constant of the solvent in F/m, T denotes the temperature of the furnace water in K, and Z₁Indicates the number of charges of the first ion, Z₂Representing the charge number of a second ion, wherein the first ion and the second ion are two ions ionized by the same electrolyte in the furnace water;

an intermediate amount calculation unit for calculating an intermediate amount q from the limit molar conductivity of each ion in the furnace water and the number of charges charged to the ion, the intermediate amount q being calculated by the following formula:

$q=\frac{\left|Z_1{Z}_2\right|({\mathrm{\λ}}_1^{\mathrm{\∞}}+{\mathrm{\λ}}_2^{\mathrm{\∞}})}{\left(\right|Z_1|+|Z_2\left|\right)\left(\right|Z_1|{\mathrm{\λ}}_2^{\mathrm{\∞}}+|Z_2\left|{\mathrm{\λ}}_1^{\mathrm{\∞}}\right)}---\left(3\right)$

wherein q represents the intermediate quantity in the unit of S.m²·mol^-1；Z₁Represents the number of charges, Z, of the first ion₂Representing the charge number of the second ions, wherein the first ions and the second ions are two ions ionized by the same electrolyte in the furnace water;representing the limiting molar conductivity of said first ion,represents the limiting molar conductivity of the second ion;

a drop value calculation unit for calculating a drop value α of the molar conductivity due to the relaxation effect based on the number of charges charged to the ions, the intermediate amount q, the dielectric constant of the solvent, and the furnace water temperature, the drop value α being calculated by the following formula:

$\mathrm{\α}=\frac{2.801\×{10}^6}{{\left(DT\right)}^{3/2}}\left|Z_1{Z}_2\right|\frac{q}{1+\sqrt{q}}---\left(4\right)$

wherein α represents the decrease in molar conductivity due to relaxation effect, in units of S.m²·mol^-1(ii) a D represents the dielectric constant of the solvent, in F/m; t represents the furnace water temperature in K; z₁Represents the number of charges, Z, of the first ion₂Representing the charge number of the second ions, wherein the first ions and the second ions are two ions ionized by the same electrolyte in the furnace water; q is the said intermediate quantity, in units of S.m²·mol^-1；

A first constant coefficient calculation unit, configured to calculate a first constant coefficient S according to the drop value α, the drop value β, and the ion limit molar conductivity, where the first constant coefficient S is calculated by the following formula:

S＝αλ_i ^∞+β (5)

wherein α represents the decrease in molar conductivity due to relaxation effect, in units of S.m²·mol^-1β shows the decrease in molar conductivity due to the electrophoretic effect, in units of S.m²·mol^-1；Represents the ultimate molar conductivity of the i-th ion in the furnace water in the unit of S.m²·mol^-1。

A second constant coefficient calculation unit, configured to calculate a second constant coefficient E according to the number of charges carried by each ion in the furnace water, the dielectric constant of the solvent, the temperature of the furnace water, the viscosity of the solvent, and the limiting molar conductivity of each ion, where the second constant coefficient E is calculated as follows:

$E^{\left(a\right)}=\frac{5.885\×{10}^{12}}{{\left(DT\right)}^3}{\left(Z_1{Z}_2\right)}^2{\mathrm{q\λ}}_i^{\mathrm{\∞}}---\left(6\right)$

$E^{\left(b\right)}=-\frac{4.332\×{10}^7}{\mathrm{\η}{\left(DT\right)}^2}\left(\right|Z_1|+|Z_2\left|\right){(Z_1+Z_2)}^3---\left(7\right)$

$E^{\left(c\right)}=-\frac{8.665\×{10}^7}{\mathrm{\η}{\left(DT\right)}^2}\frac{\left(Z_1^4+Z_2^4\right)}{2\left(\left|Z_1\right|+\left|Z_2\right|\right)}+\left|Z_1{Z}_2\right|q\frac{\left|Z_1\right|{\mathrm{\λ}}_1^{\mathrm{\∞}}+\left|Z_2\right|{\mathrm{\λ}}_2^{\mathrm{\∞}}}{{\mathrm{\λ}}_i^{\mathrm{\∞}}}---\left(8\right)$

E＝E^(a)+E^(b)+E^(c)(9)

wherein E is^(a)、E^(b)、E^(c)Representing the intermediate transition amount of the calculation process of the second constant coefficient E, wherein E represents the second constant coefficient, D represents the dielectric constant of the solvent and has the unit of F/m; t represents the furnace water temperature in K; z₁Represents the number of charges, Z, of the first ion₂Representing the charge number of the second ions, wherein the first ions and the second ions are two ions ionized by the same electrolyte in the furnace water; q is the said intermediate quantity, in units of S.m²·mol^-1；Represents the ultimate molar conductivity of the i-th ion in the furnace water in the unit of S.m²·mol^-1η represents the solvent viscosity in Pa · s;representing the limiting molar conductivity of said first ion,the limit molar conductivity of the second ion is shown, and the first ion and the second ion are two ions ionized by the same electrolyte in the furnace water.