阅读说明：本技术 一种火电厂煤热解气制氢系统及方法 (Thermal power plant coal pyrolysis gas hydrogen production system and method ) 是由 陈辉 杨豫森 崔华 于 2019-03-19 设计创作，主要内容包括：本发明公开了一种火电厂煤热解气制氢系统及方法,其包括电站锅炉(10),所述火电厂煤热解气制氢系统包括煤预处理设备、气化炉(1)及气体净化及分离装置(8)；所述煤预处理设备包括水煤浆加工处理设备或电站锅炉制粉系统(12)中至少一种；所述气化炉上设有进料口(14),所述进料口与煤预处理设备相连接；经过所述煤预处理设备的煤产物与气化剂在气化炉内反应生成混合气；所述气体净化及分离装置(8)一端与气化炉相连接,另一端与电站锅炉(10)相连接；所述混合气在气体净化及分离装置(8)内转化为氢气和废气,所述废气输送至电站锅炉(10)；本发明将充分利用火电厂的设备与物料,有效利用能源,降低气化炉能耗,提高了产氢量。(The invention discloses a system and a method for producing hydrogen from coal pyrolysis gas of a thermal power plant, which comprises a power station boiler (10), wherein the system for producing hydrogen from coal pyrolysis gas of the thermal power plant comprises coal pretreatment equipment, a gasification furnace (1) and a gas purification and separation device (8); the coal pretreatment equipment comprises at least one of coal water slurry processing equipment or a power station boiler pulverizing system (12); a feed inlet (14) is formed in the gasification furnace and is connected with coal pretreatment equipment; the coal product passing through the coal pretreatment equipment reacts with a gasification agent in a gasification furnace to generate mixed gas; one end of the gas purification and separation device (8) is connected with the gasification furnace, and the other end is connected with the power station boiler (10); the gas mixture is converted into hydrogen and waste gas in a gas purification and separation device (8), and the waste gas is conveyed to a power station boiler (10); the invention fully utilizes the equipment and materials of the thermal power plant, effectively utilizes energy, reduces the energy consumption of the gasification furnace and improves the hydrogen yield.)

1. The utility model provides a thermal power plant pyrolysis of coal gas hydrogen manufacturing system, its includes power boiler (10), its characterized in that: the thermal power plant coal pyrolysis gas hydrogen production system comprises coal pretreatment equipment, a gasification furnace (1) and a gas purification and separation device (8);

wherein the coal pretreatment equipment comprises at least one of coal water slurry processing equipment or a power station boiler pulverizing system (12);

a feed inlet (14) is formed in the gasification furnace (1), and the feed inlet (14) is connected with coal pretreatment equipment; the coal product passing through the coal pretreatment equipment reacts with a gasifying agent in a gasification furnace (1) to generate mixed gas;

one end of the gas purification and separation device (8) is connected with the gasification furnace (1), and the other end is connected with the power station boiler (10); the gas mixture is converted in a gas purification and separation device (8) into hydrogen and exhaust gas, which is fed to a utility boiler (10).

2. The thermal power plant pyrolysis of coal gas hydrogen production system of claim 1, characterized in that: the gasifying agent is at least one of air, oxygen, water vapor and high-temperature flue gas.

3. The thermal power plant pyrolysis of coal gas hydrogen generation system of claim 2, characterized in that: the power station boiler (10) is connected with the gasification furnace (1), and the high-temperature flue gas comes from the high-temperature flue gas of the power station boiler (10).

4. The thermal power plant pyrolysis of coal gas hydrogen production system of claim 2 or 3, characterized in that: the coal pyrolysis gas hydrogen production system of the thermal power plant comprises a steam turbine (5), wherein the steam turbine (5) is connected with the gasification furnace (1), and the steam comes from main steam or extracted steam of the steam turbine (5).

5. The thermal power plant pyrolysis of coal gas hydrogen production system of claim 1, characterized in that: the thermal power plant comprises an economizer (6), a reheater, an air preheater and a denitration device, wherein the gas purification and separation device (8) purifies and separates the obtained waste gas and sends the waste gas back to the front side of one of the reheater, the economizer (6), the air preheater and the denitration device in the boiler flue according to the temperature of the waste gas.

6. The thermal power plant pyrolysis of coal gas hydrogen production system of claim 1, characterized in that: the thermal power plant pyrolysis coal gas hydrogen production system comprises a cooler (2), wherein the cooler (2) is connected with a gasification furnace (1), a power station boiler (10) and a steam turbine (5); the medium in the cooler (2) is boiler water of a thermal power plant, the boiler water generates steam through the cooler (2), and the steam is conveyed to the steam turbine (5).

7. The thermal power plant pyrolysis of coal gas hydrogen production system of claim 1, characterized in that: the pyrolysis raw material coal powder directly comes from a coal mill and a coal pulverizing system of a thermal power plant; and/or the coal water slurry processing equipment is a low-speed coal mill (13) of a power station of a thermal power plant.

8. The thermal power plant pyrolysis of coal gas hydrogen production system of claim 1, characterized in that: the hydrogen obtained by purification and separation of the gas purification and separation device (8) is sent into a hydrogen storage tank or a hydrogen pipeline for external delivery, and is sold externally in the form of bottled gas, a prying tank car or pipeline gas.

9. The thermal power plant pyrolysis of coal gas hydrogen production system of claim 1, characterized in that: the gasification furnace (1) is provided with a catalyst adding port, and the catalyst is selected according to the type of the material fed into the gasification furnace (1).

10. A method for producing hydrogen from coal pyrolysis gas of a thermal power plant by using the system for producing hydrogen from coal pyrolysis gas of a thermal power plant according to any one of claims 1 to 9, characterized in that: the method comprises the following steps:

s1: selecting the state of the coal raw material fed into the gasification furnace according to the existing equipment of the thermal power plant and the condition of a flue gas and steam thermodynamic system; if the coal powder is pulverized coal, S2 is executed; if the coal water slurry is the coal water slurry, S3 is executed;

s2: selecting a gasification process according to the type of coal processed by a coal mill of a thermal power plant and the granularity of pulverized coal; and determining the gasifying agent corresponding to the corresponding gasifying process; then, S4 is executed;

s3: selecting a gasification process according to the coal amount and the coal water slurry concentration processed by a low-speed coal mill of a thermal power plant; and determining the gasifying agent corresponding to the corresponding gasifying process; then, S4 is executed;

s4: sending the pretreated coal raw material and a corresponding gasification agent into a corresponding gasification furnace, and carrying out coal gasification reaction to obtain mixed gas;

s5: sending the generated mixed gas into a gas purification and separation device for purification treatment; separating the purified gas to obtain hydrogen; the remaining exhaust gases are separated and fed to the utility boiler (10).

Technical Field

The invention belongs to the field of hydrogen production by pyrolysis and gasification, in particular to a system and a method for producing hydrogen by pyrolyzing coal by using boiler flue gas and water vapor of a thermal power plant, and particularly provides a system and a method for producing hydrogen by pyrolyzing coal gas in the thermal power plant.

Background

Hydrogen is currently recognized as the cleanest fuel and also a very important chemical feedstock. Therefore, hydrogen will become a very important clean energy source in the 21 st century. At present, high attention is paid to the development of hydrogen production technology in all countries in the world. In general, hydrogen production techniques can be divided into two broad categories: (1) hydrogen is produced by water electrolysis; (2) the hydrogen is produced by converting other primary energy sources, mainly fossil energy sources (coal, petroleum and natural gas) are used as raw materials to be subjected to conversion reaction with water vapor at high temperature, carbon in the fossil energy is firstly changed into CO, and then the CO is converted into CO through CO conversion (namely water gas conversion) reaction₂While, H₂O is converted to hydrogen.

The conversion of hydrogen from other primary energy sources, such as pyrolysis gasification of coal and renewable energy fuels, is an important source of hydrogen in the future. The domestic patent 200710017691.6 invented a supercritical water fluidized bed reactor, and the domestic patent 201610570395.8 improved and invented a raffinate recycling coal supercritical water gasification hydrogen production device and method, but the supercritical water gasification device has high temperature and high pressure, and the device itself consumes a lot of energy.

How to reduce the energy consumption for preparing high-temperature water vapor and coal powder or coal water slurry in the hydrogen production process by pyrolysis and gasification becomes a problem to be solved urgently.

The invention is provided in view of the above.

Disclosure of Invention

Aiming at the problems in the prior art, the invention aims to provide a system and a method for producing hydrogen from coal pyrolysis gas in a thermal power plant.

In order to realize the purpose, the invention adopts the following technical scheme:

a thermal power plant pyrolysis of coal gas hydrogen production system, it includes the power plant boiler, the said thermal power plant pyrolysis of coal gas hydrogen production system includes coal preconditioning plant, gasification furnace and gas purification and separation facility;

the coal pretreatment equipment comprises at least one of coal water slurry processing equipment or a power station boiler pulverizing system;

a feed port is arranged on the gasification furnace and is connected with coal pretreatment equipment; the coal product passing through the coal pretreatment equipment reacts with a gasification agent in a gasification furnace to generate mixed gas;

one end of the gas purification and separation device is connected with the gasification furnace, and the other end of the gas purification and separation device is connected with the power station boiler; the gas mixture is converted into hydrogen and waste gas in a gas purification and separation device, and the waste gas is conveyed to a power station boiler.

Preferably, the gasifying agent is at least one of air, oxygen, water vapor and high-temperature flue gas.

Preferably, the power station boiler is connected with a gasification furnace, and the high-temperature flue gas is from the high-temperature flue gas of the power station boiler.

Preferably, the system for preparing hydrogen from coal pyrolysis gas in the thermal power plant comprises a steam turbine, wherein the steam turbine is connected with the gasification furnace, and the steam comes from main steam or extracted steam of the steam turbine.

Preferably, the thermal power plant comprises an economizer, a reheater, an air preheater and a denitration device, and the gas purification and separation device purifies and separates the obtained exhaust gas and sends the exhaust gas back to the front side of one of the reheater, the economizer, the air preheater and the denitration device in the boiler flue according to the temperature of the exhaust gas.

Preferably, the thermal power plant pyrolysis coal gas hydrogen production system comprises a cooler, wherein the cooler is connected with a gasification furnace, a power station boiler and a steam turbine; the medium in the cooler is boiler water of a thermal power plant, the boiler water generates steam through the cooler, and the steam is conveyed to the steam turbine.

Preferably, the pyrolysis raw material coal powder directly comes from a coal mill and a coal pulverizing system of a thermal power plant; and/or the coal water slurry processing equipment is a low-speed coal mill of a power station of a thermal power plant.

Preferably, the hydrogen obtained by purification and separation of the gas purification and separation device is sent to a hydrogen storage tank or a hydrogen pipeline for external delivery, and is sold externally in the form of bottled gas, a prying tank truck or pipeline gas.

Preferably, the gasification furnace is provided with a catalyst adding port, and the catalyst is selected according to the type of the material fed into the gasification furnace.

The method for preparing the hydrogen from the coal pyrolysis gas of the thermal power plant uses the coal pyrolysis gas hydrogen preparation system of the thermal power plant, and is characterized in that: the method comprises the following steps:

s1: selecting the state of the coal raw material fed into the gasification furnace according to the existing equipment of the thermal power plant and the condition of a flue gas and steam thermodynamic system; if the coal powder is pulverized coal, S2 is executed; if the coal water slurry is the coal water slurry, S3 is executed;

s2: selecting a gasification process according to the type of coal processed by a coal mill of a thermal power plant and the granularity of pulverized coal; and determining the gasifying agent corresponding to the corresponding gasifying process; then, S4 is executed;

s3: selecting a gasification process according to the coal amount and the coal water slurry concentration processed by a low-speed coal mill of a thermal power plant; and determining the gasifying agent corresponding to the corresponding gasifying process; then, S4 is executed;

s4: sending the pretreated coal raw material and a corresponding gasification agent into a corresponding gasification furnace, and carrying out coal gasification reaction to obtain mixed gas;

s5: sending the generated mixed gas into a gas purification and separation device for purification treatment; separating the purified gas to obtain hydrogen; and separating residual waste gas and sending the waste gas into a power station boiler.

Advantageous effects

(1) The high-temperature flue gas of the boiler of the thermal power plant is used as a gasifying agent, so that the waste heat of the flue gas is efficiently utilized, and the energy consumption of the gasification furnace is reduced.

(2) The high-temperature extracted steam of a steam turbine of a thermal power plant is used as a gasifying agent, the extracted steam waste heat and the steam working medium are efficiently utilized, the energy consumption of the gasification furnace is reduced, and the hydrogen yield is improved.

(3) Coal powder produced by a coal mill and a coal pulverizing system of a thermal power plant is directly utilized to carry out coal powder pyrolysis hydrogen production.

(4) Coal, additives, water and the like are mixed and processed in a coal mill to produce the coal water slurry by directly utilizing a low-speed steel ball coal mill of a thermal power plant.

(5) The waste gas separated by the gas purification and separation device is directly discharged into a boiler of a thermal power plant, and the pyrolysis gasification waste gas is treated by using a boiler flue gas treatment system, so that the waste gas treatment cost of the gasification furnace is reduced.

Drawings

FIG. 1 is a schematic diagram of a coal powder pyrolysis hydrogen production system of a thermal power plant according to an embodiment of the coal pyrolysis gas hydrogen production system of the thermal power plant;

FIG. 2 is a schematic diagram of a specific situation of a coal powder pyrolysis hydrogen production system of a thermal power plant according to an embodiment of the coal pyrolysis gas hydrogen production system of the thermal power plant;

FIG. 3 shows a coal pyrolysis hydrogen production method of a thermal power plant according to an embodiment of the coal pyrolysis gas hydrogen production system of the thermal power plant;

FIG. 4 is a schematic diagram of a coal water slurry pyrolysis hydrogen production system of a thermal power plant according to a second embodiment of the coal pyrolysis gas hydrogen production system of the thermal power plant;

FIG. 5 shows a coal water slurry pyrolysis hydrogen production method in a second embodiment of the coal pyrolysis gas hydrogen production system in a thermal power plant of the invention;

FIG. 6 is a schematic diagram of a coal pyrolysis gas hydrogen production system of a third thermal power plant according to an embodiment of the coal pyrolysis gas hydrogen production system of the thermal power plant;

FIG. 7 shows a third method for producing hydrogen from coal pyrolysis gas of a thermal power plant according to an embodiment of the system for producing hydrogen from coal pyrolysis gas of a thermal power plant of the invention;

FIG. 8 is a schematic diagram of a thermal coal gasification hydrogen production system of a thermal power plant according to an embodiment of the thermal coal gasification hydrogen production system of the thermal power plant;

fig. 9 shows a method for producing hydrogen from coal pyrolysis gas of a thermal power plant according to an embodiment of the system for producing hydrogen from coal pyrolysis gas of a thermal power plant.

Description of the reference numerals

To further clarify the structure and connection between the various components of the present invention, the following reference numerals are given and described.

The system comprises a gasification furnace 1, a cooler 2, a steam pocket 3, a superheater 4, a steam turbine 5, an economizer 6, a boiler flue 7, a gas purification and separation device 8, a power station boiler 10, a valve 11, a power station boiler pulverizing system 12, a power station low-speed coal mill 13, a feed inlet 14 and a slag discharge port 15.

The technical scheme of the invention can be more clearly understood and explained by combining the embodiment of the invention through the reference sign description.

Detailed Description

The present invention is further described below in conjunction with specific examples to enable those skilled in the art to better understand the present invention and to practice it, but the scope of the present invention as claimed is not limited to the scope described in the specific embodiments. It should be noted that the embodiments and features of the embodiments in the present application may be arbitrarily combined with each other without conflict.

The core of the invention is to provide a system and a method for preparing hydrogen from coal pyrolysis gas in a thermal power plant, the system can realize low-energy-consumption hydrogen preparation from the coal pyrolysis gas, and the method comprises the steps of preparing hydrogen from the coal pyrolysis gas.