CN112082139B

CN112082139B - Boiler system with steam flow and heating power synergistic effect

Info

Publication number: CN112082139B
Application number: CN201910524914.0A
Authority: CN
Inventors: 李佳航; 王逸龙
Original assignee: Suqian Yili New Energy Co ltd
Current assignee: Elion Technology Suqian Co ltd
Priority date: 2019-06-18
Filing date: 2019-06-18
Publication date: 2022-12-13
Anticipated expiration: 2039-06-18
Also published as: CN112082139A

Abstract

The invention provides a boiler system with synergistic effect of steam flow and heating power, which comprises a boiler and a heat exchanger, wherein steam generated by the boiler enters the heat exchanger through a steam pipeline and exchanges heat with air entering the heat exchanger, and a controller automatically controls the heating power of an electric heater according to steam flow data output in unit time measured by a flow sensor; if the measured steam flow is lower than a certain value, the controller controls the heating power of the electric heater to be increased; the controller controls the reduction of the heating power of the electric heater if the flow rate measured by the flow rate sensor is higher than a certain value. The invention intelligently controls the power of the electric heater according to the steam output quantity, and can intelligently control the heating power according to the steam output quantity, thereby realizing the cooperative heat exchange function between the temperature of the steam at the outlet of the heater and the boiler according to the actual condition and meeting the actual working requirement.

Description

Boiler system with steam flow and heating power synergistic effect

Technical Field

The invention relates to an evaporator technology, in particular to an intelligent starting boiler system.

Background

Boilers are mechanical devices that use the heat energy of a fuel or other energy source to heat water into steam. The boiler has wide application field and is widely applied to places such as clothing factories, dry cleaning shops, restaurants, bunkers, dining halls, factories and mines, bean product factories and the like.

The existing boiler mostly adopts gas or fuel oil for heating, and the heating efficiency is low, but the research on the boiler utilizing waste heat is not much.

The existing boiler has low output efficiency and low intelligent degree, so that the boiler for flue gas waste heat based on intelligent control needs to be designed.

Aiming at the problems, the invention is improved on the basis of the prior invention, and provides a boiler with a new structure, which makes full use of heat sources, reduces energy consumption and realizes intelligent control.

Disclosure of Invention

In order to solve the problems, the invention is improved on the basis of the invention, and provides a novel intelligent boiler system to realize the full utilization of heat.

In order to achieve the purpose, the technical scheme of the invention is as follows:

the utility model provides a boiler system, includes boiler and heat exchanger, during steam that the boiler produced passed through steam pipe way entering heat exchanger, carries out the heat exchange with the air that gets into in the heat exchanger, the boiler includes electric heating part, steam box, electric heating part sets up in the steam box, the steam box includes inlet tube and steam outlet, set up flow sensor on the steam outlet pipeline for measure the steam flow of unit interval output, flow sensor and controller data connection. The controller automatically controls the heating power of the electric heater according to the steam flow data output in unit time measured by the flow sensor;

if the measured steam flow is lower than a certain value, the controller controls the heating power of the electric heater to be increased; the controller controls the controller to control the reduction of the heating power of the electric heater if the flow rate measured by the flow rate sensor is higher than a certain value.

Preferably, the electric heating part comprises a first header, a second header and a coil, the coil is communicated with the first header and the second header to form a closed circulation of the heating fluid, and the electric heater is arranged in the first header; the first header is filled with phase-change fluid; the number of the coil pipes is one or more, each coil pipe comprises a plurality of arc-shaped heat exchange pipes, the center lines of the arc-shaped heat exchange pipes are arcs taking the first header as a concentric circle, and the end parts of the adjacent heat exchange pipes are communicated, so that the end parts of the heat exchange pipes form free ends of the heat exchange pipes; the electric heater is arranged into a plurality of sections along the height direction, each section is independently controlled, the electric heater is sequentially started from the lower end along the height direction in a half period T/2 along with the change of time until all the sections are started, and then is sequentially closed from the upper end in the following half period T/2 until the period is ended and all the sections are closed.

Compared with the prior art, the invention has the following advantages:

1. the invention intelligently controls the power of the electric heater according to the steam output quantity, and can intelligently control the heating power according to the steam output quantity, thereby realizing the cooperative heat exchange function between the temperature of the steam at the outlet of the heater and the boiler according to the actual condition and meeting the actual working requirement.

2. The invention designs a layout of an electric heating component with a novel structure in a steam box, which can further improve the heating efficiency.

3. The electric heating part of the invention intermittently heats in a period, and can realize the periodic frequent vibration of the elastic coil, thereby realizing good descaling and heating effects.

4. The invention increases the heating power of the coil pipe periodically and continuously and reduces the heating power, so that the heated fluid can generate the volume which is continuously in a changing state after being heated, and the free end of the coil pipe is induced to generate vibration, thereby strengthening heat transfer.

5. The invention optimizes the optimal relationship of the parameters of the coil through a large amount of experiments and numerical simulation, thereby realizing the optimal heating efficiency.

Drawings

FIG. 1 is a schematic structural view of a boiler system according to the present invention.

FIG. 2 is a schematic diagram of the control architecture of the boiler system of the present invention.

Fig. 3 is a plan view of an electric heating part of the electric heating boiler of the present invention.

Fig. 4 is a front view of the electric heating part.

Fig. 5 is a coordinate schematic of gap heating by an electrical heating element.

Fig. 6 is a graph showing the coordinates of the periodic increase and decrease in heating power of the electric heating element.

FIG. 7 is a schematic diagram of the coordinates of another embodiment of the periodic increase and decrease of the heating power of the electric heating element.

Fig. 8 is a coordinate diagram illustrating linear variation of heating power of the electric heating part.

Fig. 9 is a schematic layout view of an electric heating part provided in a round steam box.

Fig. 10 is a schematic view of a coil configuration.

Fig. 11 is a schematic view of the steam box structure.

In the figure: 1. boiler, 2, heat exchanger, 3, steam pipeline, 4, water return pipeline, 5, fan, 6, sensor, 7 controller, 8, coil pipe, 9, first header, 10, free end, 11, free end, 12, water inlet pipe, 13, steam outlet, 14, free end, 15, second header, 16, connection point, 17, electric heating component, 18, steam box, 19 heat exchange pipe, 20 electric heater

Detailed Description

The following detailed description of embodiments of the invention refers to the accompanying drawings.

In this document, "/" denotes division and "×", "denotes multiplication, referring to formulas, if not specifically stated.

A steam boiler system, as shown in fig. 1, includes a boiler 1 and a heat exchanger 2, the boiler 1 generating steam. The steam enters the heat exchanger 2 through a steam pipe 3. The air enters the heat exchanger to exchange heat in the heat exchanger, and then returns to the boiler through a water return pipeline 4 to continue heating. The air enters the heat exchanger 2 through a fan 5.

With the above structure, steam generated in the boiler enters the heat exchanger, and heats air in the heat exchanger, thereby forming hot air.

As a modification, the steam pipeline 3 is provided with a flow detector 6 for detecting whether steam flows through, the flow detector 6 and the fan 5 are in data connection with a controller 7, and the controller automatically controls the on and off of the fan according to the data detected by the flow detector.

Preferably, the controller automatically controlling the fan to be turned on and off according to the data detected by the flow monitor includes the steps of:

1) The flow detector detects whether the steam flows through and transmits the detection data to the controller;

2) The controller judges whether the steam flows through according to the detected data;

3) And the controller controls whether the fan is started or not according to the judgment result.

Preferably, the controller controls the fan to be started when judging that steam flows out, so that air enters the heat exchanger for heat exchange, and controls the fan to be closed when judging that no steam flows out.

By the method, the fan can be intelligently controlled to be started according to the flow of the steam, so that the cooperative heat exchange function between the heat exchanger and the boiler can be realized according to actual conditions, and the actual working requirement can be met. Therefore, the heat can be fully utilized, and the waste of excessive heat is avoided.

As an improvement, the steam pipeline 3 is provided with a flow sensor for detecting the steam flow, the flow sensor and the fan 5 are in data connection with a controller 7, and the controller automatically controls the frequency of the fan according to the data detected by the flow monitor.

Preferably, the controller automatically controlling the frequency of the fan according to the data detected by the flow sensor includes the following steps:

1) The flow sensor detects the flow of the steam and transmits the detection data to the controller;

2) The controller judges the change of the flow according to the detected data;

3) And the controller controls the frequency of the fan according to the judgment result.

Preferably, when the controller judges that the flow increases, the frequency of the fan is controlled to increase, so that more air enters the heat exchanger to exchange heat, and when the controller judges that the flow decreases, the frequency of the fan is controlled to decrease, so that less air enters the heat exchanger to exchange heat.

By the method, the frequency of the fan can be intelligently controlled according to the steam flow, so that the cooperative heat exchange function between the heat exchanger and the boiler can be realized according to actual conditions, and the actual working requirement can be met. Therefore, the heat can be fully utilized, and the waste of excessive heat is avoided.

As another improvement, the frequency of the fan can be automatically controlled according to the detected flow rate of the steam, the temperature of the steam and the pressure.

The steam pipeline 3 is provided with a flow sensor for detecting the flow of steam, the steam pipeline is provided with a temperature sensor and a pressure sensor for detecting the temperature and the pressure of the steam, the flow sensor, the temperature sensor and the fan 5 are in data connection with the controller 7, and the controller automatically controls the frequency of the fan according to the data detected by the flow monitor, the temperature sensor and the pressure sensor.

Preferably, the controller automatically controlling the frequency of the fan according to the data detected by the flow sensor, the temperature sensor and the pressure sensor comprises the following steps:

1) The flow sensor detects the flow, the temperature and the pressure of the steam and transmits the detection data to the controller;

2) The controller judges the change of the total heat of the steam according to the detected data;

Preferably, when the controller judges that the total heat of the steam is increased, the frequency of the fan is controlled to be increased, so that more air enters the heat exchanger for heat exchange, and when the controller judges that the total heat is reduced, the frequency of the fan is controlled to be reduced, so that less air enters the heat exchanger for heat exchange.

The total heat is calculated by retrieving a database accessed in the controller to account for the heat contained in the temperature difference between the water vapor and the heating temperature to which the air is to be heated. Such as the thermodynamic water vapor temperature pressure enthalpy table.

Preferably, the boiler comprises an electric heating element 17, a steam box 18, the electric heating element 17 being arranged in the steam box 18, the steam box 18 comprising a water inlet pipe 12 and a steam outlet 13. A steam outlet 13 is provided in the upper part of the steam box.

Preferably, the steam box is of cylindrical construction.

Fig. 3 shows a top view of the electric heating part 17, as shown in fig. 3, the electric heating part 17 includes a first header 9, a second header 15 and a coil 8, the coil 8 is communicated with the first header 9 and the second header 15, the fluid is circulated in the first header 9 and the second header 15 and the coil 8 in a closed manner, an electric heater 20 is provided in the electric heating part 17, and the electric heater 20 is used for heating the internal fluid of the electric heating part 17 and then heating the water in the steam box by the heated fluid.

As shown in fig. 3-4, an electric heater 20 is provided within the first header 9; the first header 9 is filled with a phase-change fluid; the number of the coil pipes 8 is one or more, each coil pipe 8 comprises a plurality of arc-shaped heat exchange tubes 19, the center lines of the plurality of arc-shaped heat exchange tubes 19 are arcs which are concentric circles around the first header 9, the end parts of the adjacent heat exchange tubes 19 are communicated, and fluid is formed to flow in series between the first header 9 and the second header 15, so that the end parts of the heat exchange tubes form the free ends 10 and 4 of the heat exchange tubes; the fluid is phase-change fluid, vapor-liquid phase-change liquid, the electric heating part is in data connection with the controller, and the controller controls the heating power of the electric heating part to periodically change along with the change of time.

Preferably, the first header 9 and the second header 15 are arranged along the height direction.

It has been found in research and practice that continuous power-stable heating of the electric heater results in fluid-forming stability of the internal electric heating components, i.e. the fluid is not flowing or is flowing little, or the flow is stable, resulting in greatly reduced vibration performance of the coil 8, thereby affecting the efficiency of descaling and heating of the coil 8. There is therefore a need for an improvement to the electrical heating coil described above as follows.

Preferably, the heating power is a batch heating method.

As shown in fig. 5, the heating power P of the electric heater varies regularly during one period time T as follows:

p = n, where n is a constant number in watts (W), i.e. the heating power remains constant, for a half period of 0-T/2;

p =0 in half period of T/2-T. I.e. the electric heater does not heat.

T is 50 to 80 minutes, wherein 4000W straw-woven fabric n-straw-woven fabric 5000W.

By heating through the time variability, the fluid can be frequently evaporated, expanded and contracted in the elastic heat exchange tube, so that the elastic heat exchange tube is continuously driven to vibrate, and the heating efficiency and the descaling operation can be further realized.

Preferably, the electric heater 20 is provided in a plurality, each electric heater is independently controlled, and the number of the electric heaters which are activated is periodically changed along with the change of time.

Preferably, the number of the electric heaters is n, one electric heater is started at intervals of T/2n in one period T until the heaters are all started at the time of T/2n, and then one electric heater is stopped at intervals of T/2n until the heaters are all stopped at the time of T.

Preferably, the heating power of each electric heater is the same. The relationship diagram is shown in fig. 4.

Preferably, the electric heater is arranged in a plurality of sections along the height direction, each section is independently controlled, and the electric heater is sequentially started from the lower end to all the sections along the height direction in a half period T/2 along with the change of time, and then is sequentially closed from the upper end to all the sections in the following half period T/2 along with the change of time.

That is, assuming that the electric heater is n segments, in a period T, every T/2n time, starting one segment from the lower end until all segments are started at T/2n time, and then every T/2n time, starting from the upper end, closing one segment until all segments are closed at T time.

Preferably, the heating power is the same for each section. The relationship diagram is shown in fig. 4.

The electric heater is started from the lower part upwards gradually, so that the fluid at the lower part is fully heated, a good natural convection is formed, the flow of the fluid is further promoted, and the elastic vibration effect is increased. Through the change of the heating power with time variability, the fluid can be frequently evaporated, expanded and contracted in the elastic heat exchange tube, so that the elastic heat exchange tube is continuously driven to vibrate, and the heating efficiency and the descaling operation can be further realized.

Preferably, the number of the electric heaters 20 is multiple, each electric heater 20 has different power, one or more electric heaters can be combined to form different heating powers, in the last half cycle, according to a time sequence, the single electric heater is started firstly, the single electric heater is independently started according to a sequence that the heating power is sequentially increased, then the two electric heaters are started, the two electric heaters are independently started according to a sequence that the heating power is sequentially increased, then the number of the started electric heating parts is gradually increased, and if the number is n, the n electric heaters are independently started according to a sequence that the heating power is sequentially increased; and ensuring that the heating power of the electric heating parts is increased in sequence until all the electric heaters are started finally. In the next half period, the single electric heater is not started independently according to the sequence that the heating power is increased sequentially, then the two electric heaters are not started, the two electric heaters are not started independently according to the sequence that the heating power is increased sequentially, then the number that the electric heating parts are not started is increased gradually, and if the number is n, the n electric heaters are not started independently according to the sequence that the heating power is increased sequentially; and (3) until all the electric heaters are not started, ensuring that the heating power of the electric heaters is reduced in sequence.

For example, the number of the electric heating parts is three, the electric heating parts are a first electric heating part D1, a second electric heating part D2 and a third electric heating part D3, and the heating powers are P1, P2 and P3, wherein P1< P2< P3, P1+ P2> P3; namely, the sum of the first electric heating part and the second electric heating part is larger than that of the third electric heating part, and the first electric heating part, the second electric heating part, the third electric heating part, the first electric heating part, the second electric heating part, the third electric heating part and the third electric heating part are sequentially started according to the time sequence, then first second third, the order of not starting in the next half cycle is first, second, third, first plus second, first plus third, second plus third, then first second third.

The heating power is gradually increased and decreased through the electric heater, the flowing of the fluid is further promoted, and the elastic vibration effect is increased. Through the change of the heating power with time variability, the fluid can be frequently evaporated, expanded and contracted in the elastic heat exchange tube, so that the elastic heat exchange tube is continuously driven to vibrate, and the heating efficiency and the descaling operation can be further realized.

Preferably, the heating power of the electric heating part is linearly increased in the first half period, and the heating power of the electric heating part is linearly decreased in the second half period, see fig. 6.

The linear variation of the heating power is achieved by a variation of the input current or voltage.

By arranging the plurality of electric heaters, the starting of the electric heaters with gradually increased number is realized, and the linear change is realized.

Preferably, the period is 50 to 300 minutes, preferably 50 to 80 minutes; the average heating power of the electric heating part is 2000-4000W.

Preferably, the pipe diameter of the first manifold 9 is smaller than that of the second manifold 15, and the pipe diameter of the first manifold 9 is 0.5-0.8 times that of the second manifold 15. Through the pipe diameter change of first header and second header, can guarantee that the fluid carries out the phase transition and in the internal time of first box short, get into the coil pipe fast, fully get into the heat transfer of second box.

Preferably, the connection point 9 of the coil at the first header is lower than the connection point of the second header to the coil. This ensures that steam can rapidly pass upwardly into the second header.

Preferably, return lines are provided at the bottom of the first and second headers to ensure that fluid condensed in the second header can enter the first line.

Preferably, the first header and the second header are arranged in a height direction, the coil is arranged in a plurality along the height direction of the first header, and the pipe diameter of the coil is gradually reduced from top to bottom.

Preferably, the pipe diameter of the coil pipe is continuously reduced and continuously increased along the direction from the top to the bottom of the first header.

The pipe diameter range through the coil pipe increases, can guarantee that more steam passes through upper portion and gets into the second box, guarantees that the distribution of steam is even in all coil pipes, further reinforces the heat transfer effect for the whole vibration effect is even, and the heat transfer effect increases, further improves heat transfer effect and scale removal effect. Experiments show that better heat exchange effect and descaling effect can be obtained by adopting the structural design.

Preferably, the number of the coils is multiple along the height direction of the first header, and the distance between the adjacent coils is gradually increased from the top to the bottom.

Preferably, the spacing between the coils increases in magnitude with increasing height of the first header.

The interval range through the coil pipe increases, can guarantee that more steam passes through upper portion and gets into the second box, guarantees that the distribution of steam is even in all coil pipes, further reinforces the heat transfer effect for whole vibration effect is even, and the heat transfer effect increases, further improves heat transfer effect and scale removal effect. Experiments show that better heat exchange effect and descaling effect can be obtained by adopting the structural design.

Preferably, as shown in fig. 7, the steam box is a steam box with a circular cross section, and a plurality of electric heating parts are arranged in the steam box.

Preferably, as shown in fig. 7, one of the plurality of electric heating parts disposed in the steam box is disposed at the center of the steam box to serve as a central electric heating part, and the others are distributed around the center of the steam box to serve as peripheral electric heating parts. Through the structural design, the fluid in the steam box can fully achieve the vibration purpose, and the heat exchange effect is improved.

Preferably, the heating power of the single peripheral electric heating part is smaller than that of the central electric heating part. Through the design, the center reaches higher vibration frequency to form a central vibration source, so that the periphery is influenced, and better heat transfer enhancement and descaling effects are achieved.

Preferably, on the same horizontal heat exchange section, the fluid needs to achieve uniform vibration, and uneven heat exchange distribution is avoided. It is therefore necessary to distribute the amount of heating power among the different electric heating elements reasonably. Experiments show that the heating power ratio of the central electric heating component to the peripheral heat exchange tube electric heating component is related to two key factors, wherein one factor is related to the distance between the peripheral electric heating component and the center of the steam box (namely the distance between the circle center of the peripheral electric heating component and the circle center of the central electric heating component) and the diameter of the steam box. Therefore, the invention optimizes the optimal proportional distribution of the pulsating flow according to a large number of numerical simulations and experiments.

As preferred, steam box inner wall radius is R, the centre of a circle of central electric heating component sets up in steam box circular cross section centre of a circle, and the distance of the centre of a circle distance of peripheral electric heating component from the centre of a circle of steam box circular cross section is S, and the centre of a circle of adjacent peripheral electric heating component carries out the line with the circular cross section centre of a circle respectively, and the contained angle that two lines formed is A, and the heating power of peripheral electric heating component is the second power, and the heating power of single central electric heating component is first power, then satisfies following requirement:

first/second power = a-b × Ln (R/S); ln is a logarithmic function;

a and b are coefficients, wherein 1.9819 yarn a yarn 1.9823,0.5258 yarn b yarn 0.5264;

1.25<R/S<2.1；

1.6< first power/second power <1.9.

Wherein 35 ° < a <80 °.

Preferably, the number of the four-side distribution is 4-5.

Preferably, R is 1600 to 2400 mm, preferably 2000mm; s is 1200-2000 mm, preferably 1700mm; the diameter of the heat exchange tube is 12-20 mm, preferably 16mm; the outermost diameter of the pulsating coil is 300-560 mm, preferably 400mm. The diameter of the riser is 100-116 mm, preferably 108 mm, the height of the riser is 1.8-2.2 m, preferably 2 m, and the spacing between adjacent pulse tubes is 65-100mm. Preferably around 80 mm.

The total heating power is preferably 6000 to 14000W, and more preferably 7500W.

Further preferably, a =1.9821, b =0.5261.

The steam outlet is arranged in the middle of the upper wall of the steam box.

Preferably, the box body is of a circular cross section, and a plurality of electric heating parts are arranged, wherein one electric heating part is arranged at the center of the circle of the circular cross section, and the other electric heating parts are distributed around the center of the circle of the circular cross section.

The coils 8 are one or more groups, each group of coils 8 comprises a plurality of circular arc-shaped heat exchange tubes 19, the center lines of the circular arc-shaped heat exchange tubes 19 are circular arcs of concentric circles, and the end parts of the adjacent heat exchange tubes 19 are communicated, so that the end parts of the coils 8 form the free ends 10 and 11 of the heat exchange tubes, such as the free ends 10 and 11 in fig. 2.

Preferably, the heating fluid is a vapor-liquid phase-change fluid.

Preferably, the first header 9, the second header 15 and the coil 8 are all of a circular tube structure.

Preferably, the heat exchange tubes of coil 8 are resilient heat exchange tubes.

The heat exchange coefficient can be further improved by arranging the heat exchange tubes of the coil 8 with elastic heat exchange tubes.

Preferably, the concentric circles are circles centered on the center of the first header 9. I.e. the heat exchange tubes 19 of the coil 8 are arranged around the centre line of the first header 9.

As shown in fig. 6, the heat exchange tube 19 is not a complete circle, but a mouth is left, thereby forming the free end of the heat exchange tube. The angle of the arc of the mouth part is 65-85 degrees, namely the sum of included angles b and c in figure 8 is 65-85 degrees.

Preferably, the heat exchange tubes are aligned with their ends on the same side, in the same plane, with the extension of the ends (or the plane in which the ends lie) passing through the midline of the first header 9.

Further preferably, the electric heater 20 is an electric heating rod.

Preferably, the inner heat exchange tubes of the coil 8 are connected at a first end to the first header 9 and at a second end to one end of the adjacent outer heat exchange tubes, the outermost heat exchange tubes of the coil 8 are connected at one end to the second header 15 and the ends of the adjacent heat exchange tubes communicate to form a series arrangement.

The plane in which the first end is located forms an angle c with the plane in which the centre lines of the first header 9 and the second header 15 are located, which is 40-50 degrees.

The plane in which the second end is located forms an angle b of 25-35 degrees with the plane in which the centre lines of the first header 9 and the second header 15 are located.

Through the design of the optimized included angle, the vibration of the free end is optimized, and therefore the heating efficiency is optimized.

As shown in FIG. 10, the number of heat exchange tubes of the coil 8 is 4, and the heat exchange tubes A, B, C and D are communicated. Of course, the number is not limited to four, and a plurality of the connecting structures are provided as required, and the specific connecting structure is the same as that in fig. 8.

The number of the coil pipes 8 is multiple, and the multiple coil pipes 8 are respectively and independently connected with the first collecting pipe 9 and the second collecting pipe 15, namely, the multiple coil pipes 8 are in a parallel structure.

Preferably, the control method in the boiler 1 is as follows:

outlet steam temperature control

A temperature sensor is arranged at the position of the steam outlet of the boiler and used for measuring the temperature of the steam outlet; the temperature sensor is in data connection with a central control 7, and the controller 7 automatically controls the heating power of the electric heater according to the temperature measured by the temperature sensor.

If the temperature measured by the temperature sensor is lower than the first temperature, the controller controls the heating power of the electric heater to be increased; the controller controls the reduction of the heating power of the electric heater if the temperature measured by the temperature sensor is higher than the second temperature. This situation shows that at the first temperature, the steam produced does not meet the minimum temperature requirement of the actual demand, and the heating power needs to be increased. At the second temperature, the temperature of the generated steam is too high to exceed the actually required temperature, and at the moment, the boiler needs to reduce the heating power.

Preferably, the temperature sensor is a plurality of temperature sensors, and the controller controls the operation of the boiler according to the temperature data measured by the plurality of temperature sensors.

(II) Hot Water temperature control

Preferably, a temperature sensor is arranged in the steam box and used for measuring the temperature of water in the steam box. The temperature sensor is in data connection with a controller 7, and the controller 7 automatically controls the heating power of the electric heater according to the temperature measured by the temperature sensor.

The controller controls the increase of the heating power of the electric heater if the temperature measured by the temperature sensor is lower than a certain temperature; the controller controls the reduction of the heating power of the electric heater if the temperature measured by the sixth temperature sensor is higher than a certain temperature. This situation shows that at a certain temperature, the steam produced cannot meet the minimum temperature requirement of the actual demand because the temperature of the hot water is low, and the heating power needs to be increased. The temperature of the hot water is high, so that the temperature of the generated steam is too high and exceeds the temperature of actual needs, the heating power of the electric heater is reduced, heat is stored, and heat loss is avoided.

(III) Water level control

Preferably, a water level sensor is arranged in the steam box, a water pump is arranged on a water replenishing pipe of the steam box, the water level sensor and the water pump are in data connection with a controller 7, and the controller 7 automatically controls the power of the water pump according to the measured water level in the steam box.

Preferably, the controller 7 increases the flow of water into the steam box by controlling the power of the water pump to be increased if the water level falls, and decreases the flow of water into the steam box or stops the supply of water into the steam box by decreasing the power of the water pump or turning off the water pump if the water level is too high.

Through foretell setting, avoided the water level on the one hand to hang down the steam output rate that causes and hang down and steam drum dry combustion method, cause the damage of steam drum and produce the incident, on the other hand, avoided because the water level is too high and the water yield that causes is too big, realizes the intelligent control of water level.

(IV) controlling heating power according to water level

Preferably, a water level sensor is arranged in the steam box, the water level sensor is in data connection with the controller 3, and the controller 3 automatically controls the heating power of the electric heater according to the measured water level in the steam box.

Preferably, if the water level is too low, the controller 7 reduces the heating power of the electric heater, so as to avoid the further reduction of the water level due to the excessive steam generation caused by the excessive power in the boiler, and if the water level is too high, the controller 7 controls the electric heater to increase the heating power, so as to improve the steam generation, so as to reduce the water level.

Through foretell setting, avoided the water level to hang down the dry combustion method who causes the steam drum excessively on the one hand, caused the damage of steam drum and produced the incident, on the other hand, avoided the water yield in the box that causes because the water level is too high too big.

(V) control of heating power according to pressure

Preferably, the steam box is provided with a pressure sensor for measuring the pressure in the steam box. The pressure sensor is in data connection with a controller 7, and the controller 7 automatically controls the heating power of the electric heater according to the pressure measured by the pressure sensor.

Preferably, the controller controls the heating power of the electric heater to be increased if the pressure measured by the pressure sensor is lower than a certain pressure. If the pressure measured by the pressure sensor is higher than a certain pressure, the controller controls the heating power of the electric heater to be reduced. If the pressure measured by the pressure sensor is higher than the upper limit pressure, the controller controls the electric heater to be closed in order to avoid danger caused by excessive pressure.

Through so setting up, can come the regulation heating power according to the pressure in the steam chest to guarantee under the condition of maximize steam output, guarantee the safety of boiler.

The pressure sensor is arranged at the upper part of the steam box.

Preferably, the pressure sensor is a plurality of pressure sensors, and the controller controls the operation of the boiler according to the pressure data which is the temperature measured by the plurality of pressure sensors.

(VI) steam flow control

Preferably, a flow sensor is arranged on the steam outlet pipeline and used for measuring the steam flow produced in unit time, and the flow sensor is in data connection with the controller 7. The controller 7 automatically controls the heating power of the electric heater according to the steam flow data generated per unit time measured by the flow sensor.

Preferably, the controller 7 controls the heating power of the electric heater to be increased if the measured steam flow is below a certain value. If the flow rate measured by the pressure sensor is higher than a certain value, the controller 3 controls the controller 7 to control the decrease of the heating power of the electric heater.

Through so setting up, can adjust the heating power who gets into the boiler according to the steam quantity that the boiler produced, guarantee the invariant of steam output quantity, avoid the quantity too big or undersize, cause steam quantity not enough or extravagant, can practice thrift the waste heat energy simultaneously.

Although the present invention has been described with reference to the preferred embodiments, it is not limited thereto. Various changes and modifications may be effected by one skilled in the art without departing from the spirit and scope of the invention, as defined in the appended claims.

Claims

1. A boiler system with steam flow and heating power synergistic effect comprises a boiler and a heat exchanger, wherein steam generated by the boiler enters the heat exchanger through a steam pipeline and exchanges heat with air entering the heat exchanger, the boiler comprises an electric heating part and a steam box, the electric heating part is arranged in the steam box, the steam box comprises a water inlet pipe and a steam outlet, a flow sensor is arranged on the steam outlet pipeline and used for measuring the steam flow output in unit time, and the flow sensor is in data connection with a controller; the controller automatically controls the heating power of the electric heater according to the steam flow data output in unit time measured by the flow sensor;

if the measured steam flow is lower than a certain value, the controller controls the heating power of the electric heater to be increased; if the flow measured by the flow sensor is higher than a certain value, the controller controls the reduction of the heating power of the electric heater;

a water level sensor is arranged in the steam box, a water pump is arranged on a water replenishing pipe of the steam box, the water level sensor and the water pump are in data connection with a controller, and the controller automatically controls the power of the water pump according to the measured water level in the steam box;

the electric heating part comprises a first header, a second header and a coil, the coil is communicated with the first header and the second header to form a closed heating fluid circulation, and the electric heater is arranged in the first header; the first header is filled with phase-change fluid; the number of the coil pipes is one or more, each coil pipe comprises a plurality of arc-shaped heat exchange pipes, the center lines of the arc-shaped heat exchange pipes are arcs taking the first header as a concentric circle, and the end parts of the adjacent heat exchange pipes are communicated, so that the end parts of the heat exchange pipes form free ends of the heat exchange pipes; the electric heater is arranged into a plurality of sections along the height direction, each section is independently controlled, the electric heater is sequentially started from the lower end along the height direction in a half period T/2 along with the change of time until all the sections are started, and then is sequentially closed from the upper end in the following half period T/2 until the period is ended and all the sections are closed.