CN115948186A - Method for preparing composite coal water slurry by using baked biomass and composite coal water slurry - Google Patents

Abstract

The invention discloses a method for preparing composite coal water slurry by using baked biomass and the composite coal water slurry. The invention uses the biomass solid product after baking treatment to partially replace coal dust in the coal water slurry, thereby reducing the carbon emission generated by the consumption of fossil fuel; the liquid product obtained by baking is used for partially replacing water to be applied to the preparation of the composite coal water slurry, so that the organic liquid product generated by baking the biomass is consumed while water resources are effectively saved; thereby realizing the comprehensive utilization of resources and solving the problem of waste pollution.

Description

A method for preparing composite coal-water slurry by using roasted biomass and composite coal-water slurry

technical field

The invention belongs to the technical field of energy utilization of organic solid waste, and in particular relates to a method for preparing composite coal-water slurry by using roasted biomass and the composite coal-water slurry.

Background technique

With the development of China's social economy and the improvement of people's living standards, human consumption of energy is also increasing. Coal resources occupy an absolute major position in China's energy composition. The country has increased the mining and comprehensive utilization of coal resources. magnitude. As a coal-based liquid fuel that emerged in the 1970s, coal-water slurry is composed of 60% to 75% coal, 25% to 40% water and about 1% additives. It is a black slurry that can burn and has good It is a kind of clean energy with high combustion efficiency and low pollution, which can replace heavy oil fuel and alleviate the problem of oil energy shortage.

Biomass has the characteristics of renewability, low pollution, rich resources, and carbon neutrality. The efficient development and utilization of biomass will play a very positive role in solving energy and ecological environment problems. Biomass coal-water slurry is to mix biomass into coal-water slurry after certain treatment to form a slurry that can flow continuously, which greatly simplifies complex multi-factor environmental protection issues, thus fully reflecting the environmental protection of biomass coal-water slurry The characteristics, goals, characteristics and functions of the integrated system of resources, energy and environmental protection are reflected as a whole, which is the most prominent essence of biomass coal-water slurry. However, biomass is mainly composed of cellulose, hemicellulose, and lignin, and has poor grindability. The particle size requirements for blending and pulping are relatively high, and biomass has many pores, high moisture content, and strong water absorption, which reduces the The concentration of the slurry leads to problems such as low calorific value, low concentration, and poor slurrying properties of the biomass coal-water slurry, which cannot be used in large-scale industries.

Contents of the invention

The purpose of this section is to outline some aspects of embodiments of the invention and briefly describe some preferred embodiments. Some simplifications or omissions may be made in this section, as well as in the abstract and titles of this application, to avoid obscuring the purpose of this section, the abstract and titles, and such simplifications or omissions should not be used to limit the scope of the invention.

In view of the problems mentioned above and/or in the prior art, the present invention is proposed.

One of the objectives of the present invention is to provide a method for preparing composite coal-water slurry by using roasted biomass.

In order to solve the above-mentioned technical problems, the present invention provides the following technical solutions: a method for preparing composite coal-water slurry by using roasted biomass, comprising:

Perform torrefaction pretreatment on biomass at 220-300°C to obtain torrefied solid-phase products and torrefied liquid-phase products;

Grinding the obtained baked solid phase product;

Uniformly mixing the ground baked solid phase product with coal powder to obtain a composite coal water slurry;

Wherein, in the composite coal water slurry, the baked solid phase product exists in an amount of 2-20% by mass fraction.

As a preferred solution of the method for preparing composite coal-water slurry by using roasted biomass in the present invention, wherein: the biomass includes one or more of sawdust, straw, and peanut shells.

As a preferred scheme of the method for preparing composite coal-water slurry by roasting biomass in the present invention, wherein: the roasting pretreatment is carried out, and the temperature is raised to 220-300 °C at a heating rate of 10 °C per minute, and the roasting time is 20-60 min .

As a preferred solution of the method for preparing composite coal-water slurry by using roasted biomass in the present invention, wherein: the grinding is carried out, put into a ball mill for grinding, and then sieved through a 200-mesh sieve after grinding.

As a preferred solution of the method for preparing composite coal-water slurry by using roasted biomass in the present invention, the coal powder is obtained by mixing 100-mesh coal powder and 200-mesh coal powder at a mass ratio of 6:4.

As a preferred version of the method for preparing composite coal-water slurry using roasted biomass in the present invention, wherein: the uniform mixing also includes adding the roasted liquid phase product, solvent and dispersant; the solvent is water, The dispersant includes one of sulfonate-type segregating surfactants, polyoxyethylene series nonionic surfactants, water-soluble high molecular polymers, and complexes of anionic surfactants and nonionic surfactants. kind.

As a preferred solution of the method for preparing composite coal-water slurry by using roasted biomass in the present invention, wherein: in the composite coal-water slurry, the roasted liquid phase product exists in an amount of 3-10% by mass fraction, The solvent exists in an amount of 25.5-32.5% by mass fraction, and the dispersant exists in an amount of 0.5% by mass fraction.

As a preferred solution of the method for preparing composite coal-water slurry by using roasted biomass in the present invention, wherein: uniform mixing is carried out, mechanical stirring is used for stirring and pulping, and the stirring rate is 100-200 r/min.

Another object of the present invention is to provide the composite coal-water slurry obtained by the method described in any one of the above, which comprises 2 to 15% of baked solid phase products, 51 to 62% of coal powder, 0.5 % dispersant, 3-10% roasted liquid phase product and 25.5-32.5% solvent.

As a preferred version of the composite coal-water slurry of the present invention, wherein: it has the following characteristics:

(i) The calorific value of the fuel is 20-23MJ/kg;

(ii) The solid content rate is 60-62%;

(iii) The viscosity is 750～1150mPa·s;

(iv) Stability greater than 99%.

Compared with the prior art, the present invention has the following beneficial effects:

The present invention uses the baked biomass solid product to partially replace the coal powder in the coal-water slurry, which reduces the carbon emission caused by the consumption of fossil fuels; the liquid product obtained by using the roasted part replaces water and is applied to the composite coal-water slurry The preparation of the method effectively saves water resources and at the same time absorbs the organic liquid products produced by biomass baking; thereby realizing the comprehensive utilization of resources and solving the problem of waste pollution. The calorific value of the prepared roasted biomass coal-water slurry fuel is 20-23MJ/kg, the solid content is 60-62%, the viscosity is 750-1150mPa·s, and the stability is above 99%, which meets the requirements of industrial coal-water slurry , some are better than traditional coal water slurry.

Detailed ways

In order to make the above objects, features and advantages of the present invention more obvious and comprehensible, the specific implementation manners of the present invention will be described in detail below in conjunction with the embodiments of the specification.

In the following description, a lot of specific details are set forth in order to fully understand the present invention, but the present invention can also be implemented in other ways different from those described here, and those skilled in the art can do it without departing from the meaning of the present invention. By analogy, the present invention is therefore not limited to the specific examples disclosed below.

Second, "one embodiment" or "an embodiment" referred to herein refers to a specific feature, structure or characteristic that may be included in at least one implementation of the present invention. "In one embodiment" appearing in different places in this specification does not all refer to the same embodiment, nor is it a separate or selective embodiment that is mutually exclusive with other embodiments.

Unless otherwise specified, the raw materials used in the examples are purchased commercially.

Example 1

(1) Put the raw material maple chips into the composite grinder CM100M for grinding, weigh 20g of the ground maple chips and put them into a slender sample tube, use nitrogen as the protective gas, and flow at 90ml/min. Raise the temperature at a rate of 10°C per minute to 300°C and keep it for 30 minutes to obtain a roasted solid phase product and a roasted liquid phase product;

(2) Put the baked maple wood chips into the planetary ball mill QM-3SP04 after cooling down the temperature of the baked solid phase product, and grind them for 15 minutes, and pass through a 200-mesh sieve with a maximum aperture of 0.075mm to obtain the baked maple wood chips;

(3) Put the raw coal into the planetary ball mill QM-3SP04 and grind it fully for 15 minutes, pass through 100-mesh and 200-mesh sieves respectively, mix 100-mesh coal powder and 200-mesh coal powder according to the mass ratio of 6:4 to obtain coal powder ;

(4) 200 mesh roasted maple wood chips with a mass fraction of 5% are mixed with 0.5% sodium lignin sulfonate, 25.5% deionized water, 10% roasted liquid phase product, and 59% coal powder. - Under a type-2 multifunctional electric mixer, stir at a stirring rate of 100 to 200 r/min for 20 minutes, and stand still for 3 minutes to obtain roasted biomass coal-water slurry.

Comparative example 1

(1) Put the raw coal into the planetary ball mill QM-3SP04 and grind it fully for 15 minutes, pass through 100 mesh and 200 mesh sieves respectively, mix 100 mesh coal powder and 200 mesh coal powder according to the mass ratio of 6:4 to obtain coal powder ;

(2) Mix coal powder with mass fraction of 65%, deionized water with 34.5%, and sodium lignosulfonate with 0.5%. Stir at the stirring speed for 20 minutes and stand still for 3 minutes to obtain traditional coal water slurry.

The roasted biomass coal-water slurry obtained in Example 1 and the traditional coal-water slurry obtained in Comparative Example 1 were tested for fuel calorific value, solid content, apparent viscosity and stability, respectively. The test method of fuel calorific value shall refer to GB/T213-2008 standard; the test method of solid content, apparent viscosity and stability test shall refer to GB/T18856-2008 standard.

The fuel calorific value of traditional coal-water slurry is 21.56MJ/kg, the solid content is 60.7%, the apparent viscosity is 790mPa·s, and the stability is 97.66%. The calorific value of the roasted biomass coal-water slurry fuel prepared in Example 1 is 20.76MJ/kg, the solid content is 60.5%, the apparent viscosity is 898mPa·s, the stability is 99.62%, and some properties are better than traditional water coal pulp.

Example 2

On the basis of Example 1, adjust the baking temperature in step (1) and the blending amount of the roasted maple wood chips in step (4), and adjust the blending amount of the roasted liquid phase product accordingly, so that the roasted maple wood chips The total addition amount of the torrefied liquid phase product was maintained at 15%, and other conditions were the same as in Example 1. The properties of the prepared torrefied biomass coal-water slurry are shown in Table 1.

Table 1

From the data in Table 1, it can be seen that the roasted biomass coal-water slurry prepared with maple wood chips as the biomass raw material obtained the highest fuel heat under the condition of 6# experiment, that is, the roasting temperature was 280 °C and the blending amount was 15%. Value, up to 21.66MJ/Kg, higher than the traditional coal water slurry of Comparative Example 1.

In terms of stability, the roasted biomass coal-water slurry obtained by the method of this example is basically better than the traditional coal-water slurry in Comparative Example 1. Under the 5# experiment, that is, the roasting temperature is 280 ° C and the blending amount is 10%. The highest stability was obtained, reaching 99.71%.

In terms of apparent viscosity, the roasted biomass coal-water slurry obtained by the method of this embodiment is higher than the traditional coal-water slurry of Comparative Example 1. According to the national standard GB/T18855-2008 for coal-water slurry, the apparent viscosity should be less than 1200mPa·s , all meet the requirements under the experimental conditions.

In terms of solid content, the roasted biomass coal-water slurry obtained by the method in this example all meets the third-level requirements of the national standard GB/T18855-2008. Under the 3# experiment, that is, the roasting temperature is 260 ° C and the blending amount is 10%. The highest solid content rate was obtained, reaching 61.5%.

Considering the solid content, calorific value, stability and other indicators, the roasted biomass coal-water slurry prepared by using maple wood chips as biomass raw materials is optimal under the conditions of roasting temperature 280 °C and blending amount of 10-15%. process conditions.

Example 3

(1) Put the raw rice straw into the composite grinder CM100M for grinding, weigh 20g of the ground straw and put it into a slender sample tube, use nitrogen as the protective gas, and flow at a rate of 90ml/min. Raise the temperature at a rate of 10°C per minute to 300°C and keep it for 30 minutes. After cooling down, put the roasted straw into the planetary ball mill QM-3SP04 and grind it for 15 minutes. Pass all the roasted straw through a 200-mesh sieve with a maximum aperture of 0.075mm to obtain baking straw;

(2) Mix 5% 200-mesh roasted straw with 0.5% sodium lignosulfonate, 5% roasted liquid product, 30.5% deionized water, and 59% coal powder. Under an electric stirrer, stir at a stirring rate of 100-200 r/min for 10 minutes, and stand still for 3 minutes to obtain the roasted straw coal-water slurry.

The roasted biomass coal-water slurry obtained in Example 3 was tested for fuel calorific value, solid content, apparent viscosity and stability respectively. The test method of fuel calorific value shall refer to GB/T213-2008 standard; the test method of solid content, apparent viscosity and stability test shall refer to GB/T18856-2008 standard.

The calorific value of the roasted biomass coal-water slurry fuel prepared in Example 3 is 21.99 MJ/kg, the solid content is 60.7%, the viscosity is 1116 mPa·s, and the stability is 99.89%.

Example 4

On the basis of Example 3, adjust the roasting temperature in step (1) and the blending amount of roasted stalks in step (4), other conditions are the same as in Example 3, the performance of the roasted biomass coal-water slurry obtained As shown in table 2.

Table 2

It can be seen from the data in Table 2 that when the roasted biomass coal-water slurry made from straw is used as the biomass raw material, in terms of apparent viscosity, only 12#, 13#, and 15# experiments meet the national standard.

Under the three experimental conditions, in terms of solid content, the 13# experiment, that is, under the conditions of baking temperature 280 ° C and blending amount of 10%, the highest solid content reached 61.5%;

In terms of fuel calorific value, the 15# experiment, that is, under the conditions of baking temperature 300 ℃ and blending amount of 5%, the highest fuel calorific value obtained reached 21.99MJ/kg;

In terms of stability, the 15# experiment, that is, under the condition of baking temperature of 300°C and blending amount of 5%, the highest stability obtained is 99.89%.

Considering the solid content, calorific value, stability and other indicators, the roasted biomass coal-water slurry made from straw as raw material is the optimal process under the conditions of roasting temperature 280-300 ℃ and blending amount of 5%. condition.

Example 5

(1) Put the raw material peanut shells into the composite grinder CM100M for grinding, weigh 20g of the ground peanut shells and put them into a slender sample tube, use nitrogen as the protective gas, and flow at 90ml/min Raise the temperature at a rate of 10°C per minute to 300°C and keep it for 30 minutes. After cooling down, put the roasted peanut shells into the planetary ball mill QM-3SP04 and grind them for 15 minutes. Pass all the roasted peanut shells through 200 mesh with a maximum aperture of 0.075mm. a sieve to get roasted peanut shells;

(2) Mix 5% 200-mesh roasted peanut shells with 0.5% sodium lignosulfonate, 5% roasted liquid product, 30.5% deionized water, and 59% coal powder. Under a functional electric stirrer, stir at a stirring rate of 100-200r/min for 10 minutes, and stand still for 3 minutes to obtain a roasted peanut shell coal-water slurry.

The roasted biomass coal-water slurry obtained in Example 5 was tested for fuel calorific value, solid content, apparent viscosity and stability respectively. The test method of fuel calorific value shall refer to GB/T213-2008 standard; the test method of solid content, apparent viscosity and stability test shall refer to GB/T18856-2008 standard.

The calorific value of the roasted biomass coal-water slurry fuel prepared in Example 5 is 22.32MJ/kg, the solid content is 61.3%, the viscosity is 1011mPa·s, and the stability is 99.98%, which is partially better than the traditional coal-water slurry.

Example 6

On the basis of Example 5, adjust the roasting temperature in the step (1) and the blending amount of the roasted peanut shells in the step (4), other conditions are the same as in Example 5, the obtained roasted biomass coal-water slurry The performance is shown in Table 3.

table 3

It can be seen from the data in Table 3 that in terms of fuel calorific value, the fuel calorific value of roasted biomass coal-water slurry made from peanut shells is generally higher than that of maple wood chips and straw, and is better than that of Comparative Example 1. The traditional coal-water slurry, 17# experiment, that is, under the conditions of baking temperature 240 ℃ and blending amount of 2%, the highest fuel calorific value is 22.52MJ/kg.

In terms of apparent viscosity, the roasted biomass coal-water slurry obtained by the method of this embodiment is higher than the traditional coal-water slurry of Comparative Example 1. According to the national standard GB/T18855-2008 for coal-water slurry, the apparent viscosity should be less than 1200mPa·s , 18# experiment, that is, the apparent viscosity of the roasted biomass coal-water slurry obtained under the conditions of roasting temperature 200 °C and blending amount of 10% is much higher than the requirements of industrial coal-water slurry, and meets the requirements under other experimental conditions.

In terms of solid content, the 21# experiment, that is, under the condition of baking temperature of 300°C and blending amount of 5%, the highest solid content was 61.3%.

In terms of stability, the 21# experiment, that is, under the condition of baking temperature of 300°C and blending amount of 5%, the highest stability of 99.98% was obtained.

Considering the solid content, calorific value, stability and other indicators comprehensively, the roasted biomass coal-water slurry made from peanut shells as biomass raw materials can be baked at 300 °C with a blending amount of 5% or at a roasting temperature of 240 °C with blending The optimum process condition is when the mixing amount is 2%.

In addition, during the experiment, it was found that when the blending amount of roasted peanut shells reached 10% or more, the pulping properties were extremely poor, and the viscosity was >1500mPa·s.

Example 7

On the basis of Example 1, adjust the blending amount of the roasted liquid phase product in step (4), and adjust the amount of deionized water adaptively to ensure that the total mass of the liquid phase is the same, and other conditions are the same as in Example 1. The properties of the roasted biomass coal-water slurry obtained are shown in Table 4.

Table 4

From the data in Table 4, it can be seen that the performance of coal-water slurry has been improved when the roasted liquid phase product is mixed into the water phase, and with the increase of the calorific value of the roasted liquid phase product blending amount, all the properties have a certain degree of improvement. The increase of the apparent viscosity also increases, but all meet the requirements of industrial coal water slurry.

Comparative example 2

(1) Put the raw material maple chips into the composite grinder CM100M for grinding, weigh 20g of the ground maple chips and put them into a slender sample tube, use nitrogen as the protective gas, and flow at 90ml/min. Raise the temperature at a rate of 10°C per minute to 300°C and keep it for 30 minutes to obtain a roasted solid phase product and a roasted liquid phase product;

(2) Put the baked maple wood chips into the planetary ball mill QM-3SP04 after cooling down the temperature of the baked solid phase product, and grind them for 15 minutes, and pass through a 200-mesh sieve with a maximum aperture of 0.075mm to obtain the baked maple wood chips;

(3) Put the raw coal into the planetary ball mill QM-3SP04 and grind it fully for 15 minutes, pass through 100-mesh and 200-mesh sieves respectively, mix 100-mesh coal powder and 200-mesh coal powder according to the mass ratio of 6:4 to obtain coal powder ;

(4) 200 mesh roasted maple wood chips with a mass fraction of 20% are mixed with 0.5% sodium lignosulfonate, 25.5% deionized water, 10% roasted liquid phase product, and 44% coal powder. - Under a type-2 multifunctional electric mixer, stir at a stirring rate of 100 to 200 r/min for 20 minutes, and stand still for 3 minutes to obtain roasted biomass coal-water slurry.

The roasted biomass coal-water slurry obtained in Comparative Example 1 was tested for fuel calorific value, solid content, apparent viscosity and stability. The test method of fuel calorific value shall refer to GB/T213-2008 standard; the test method of solid content, apparent viscosity and stability test shall refer to GB/T18856-2008 standard.

The fuel calorific value of the roasted biomass coal-water slurry obtained in Comparative Example 1 was 22.54MJ/kg, the solid content rate was 63.2%, the apparent viscosity was 1658mPa·s, the stability was 99.72%, and the pH value was 6.53. The apparent viscosity of material coal water slurry is much higher than the requirements of industrial coal water slurry, and the slurry forming characteristics are extremely poor.

The present invention adopts the roasting method to control the deoxidation quality of the biomass, and partially replaces the coal powder in the coal-water slurry with the roasted biomass solid product, which reduces the carbon emission caused by the consumption of fossil fuels; Part of the liquid product replaces water and is used in the preparation of composite coal-water slurry, which effectively saves water resources and at the same time consumes organic liquid products produced by biomass roasting; the present invention uses waste biomass raw materials for roasting pretreatment to realize comprehensive utilization of resources , to solve the problem of waste pollution. The calorific value of the prepared roasted biomass coal-water slurry fuel is 20-23MJ/kg, the solid content is 60-62%, the viscosity is 750-1150mPa·s, and the stability is above 99%, which meets the requirements of industrial coal-water slurry , some are better than traditional coal water slurry.

It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention without limitation, although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be carried out Modifications or equivalent replacements without departing from the spirit and scope of the technical solution of the present invention shall be covered by the claims of the present invention.

Claims (10)

1. A method for preparing composite coal water slurry by using baked biomass is characterized by comprising the following steps: comprises the steps of (a) preparing a substrate,

carrying out baking pretreatment on the biomass at the temperature of 220-300 ℃ to obtain a baked solid-phase product and a baked liquid-phase product;

grinding the obtained baked solid-phase product;

uniformly mixing the ground baked solid-phase product with coal powder to obtain composite coal water slurry;

wherein, in the composite water-coal-slurry, the baked solid-phase product exists in the amount of 2-20% by mass fraction.

2. The method for preparing composite coal water slurry by baking biomass according to claim 1, wherein the method comprises the following steps: the biomass comprises one or more of wood chips, straws and peanut shells.

3. The method for preparing composite coal water slurry by using torrefied biomass as claimed in claim 1 or 2, wherein: the baking pretreatment is carried out, the temperature is increased to 220-300 ℃ at the temperature rising rate of 10 ℃ per minute, and the baking time is 20-60 min.

4. The method for preparing composite coal water slurry by baking biomass according to claim 3, wherein the method comprises the following steps: and grinding, namely grinding in a ball mill, and screening through a 200-mesh sieve after grinding.

5. The method for preparing composite coal water slurry by using torrefied biomass as claimed in any one of claims 1, 2 and 4, wherein the method comprises the following steps: the coal powder is prepared from 100-mesh coal powder and 200-mesh coal powder according to the mass ratio of 6:4, and mixing the components in a ratio of 4.

6. The method for preparing composite coal water slurry by using torrefied biomass according to claim 5, wherein the steps of: the step of uniformly mixing further comprises the step of adding the baking liquid phase product, a solvent and a dispersing agent; the solvent is water, and the dispersant comprises one of sulfonate type separating surfactant, polyoxyethylene series nonionic surfactant, water-soluble high molecular polymer and a compound of anionic surfactant and nonionic surfactant.

7. The method for preparing composite coal water slurry by using torrefied biomass according to claim 6, wherein the steps of: in the composite water-coal-slurry, the baking liquid-phase product is present in an amount of 3-10% by mass fraction, the solvent is present in an amount of 25.5-32.5% by mass fraction, and the dispersant is present in an amount of 0.5% by mass fraction.

8. The method for preparing composite coal water slurry by using torrefied biomass as claimed in any one of claims 1, 2, 4, 6 and 7, wherein the method comprises the following steps: the components are uniformly mixed, and mechanical stirring is adopted for stirring and pulping, wherein the stirring speed is 100-200 r/min.

9. The composite coal water slurry obtained by the method according to any one of claims 1 to 8, wherein: the composite material comprises, by mass, 2-15% of a baked solid-phase product, 51-62% of coal powder, 0.5% of a dispersant, 3-10% of a baked liquid-phase product and 25.5-32.5% of a solvent.

10. The composite coal-water slurry of claim 9, wherein: has the following characteristics:

(i) The heat value of the fuel is 20-23 MJ/kg;

(ii) The solid content is 60-62%;

(iii) The viscosity is 750 to 1150 mPa.s;

(iv) The stability is more than 99%.