WO2009129652A1

WO2009129652A1 - An electricity generation method and its device by use of the heat from blast furnace slag

Info

Publication number: WO2009129652A1
Application number: PCT/CN2008/000828
Authority: WO
Inventors: 董书通
Original assignee: Dong Shutong
Priority date: 2008-04-23
Filing date: 2008-04-23
Publication date: 2009-10-29

Abstract

An electricity generation method by use of the heat from blast furnace slag includes: the blast furnace slag is carried to a wind-quenching system(2). After the furnace slag is quenched into slag particles by wind, the slag particles quenched by wind are further crushed by a high-speed rotating impeller in a wind quenching chamber(21) to increase the heat exchange area. The crushed slag particles are carried onto a fire grate(44) of a chain grate stoker boiler by hot wind. The crushed slag particles are contacted with the coal from a coal bunker and the lime powder from a lime silo. They burn in high temperature, release heat and produce steam used for driving a steam turbine to generate electricity. The burnt slag is carried out of the furnace chamber by the fire grate(44) and becomes good cement material after water-quenched.

Description

Method and device for utilizing blast furnace slag heat to generate electricity

The present invention relates to a method and apparatus for generating electricity, and more particularly to a method and apparatus for generating electricity using blast furnace slag heat.

Background technique

With the adjustment of the national energy policy, the use of waste heat power generation is the only way to reduce the cost of enterprises and take the circular economy. In recent years, due to the rapid development of the national energy-based industry, the demand for steel has been increasing and prices have been rising, but due to steel The industry is a high-energy-consuming industry, and it is also a polluting industry. How to reduce energy consumption and obtain environmental protection requirements is a problem that every steel company must face and must solve, especially blast furnace slag. The comprehensive utilization of heat is even more urgent.

The existing utilization of waste heat power generation is to discharge low-temperature flue gas of less than 400 向外 in the industrial enterprises such as cement, building materials, steel, chemicals, ceramics, etc., waste steam, waste hot water and other waste heat resources to convert it into convenient use for transportation. The electric energy is characterized by using a heat exchanger to generate saturated steam or hot water, and then heating the saturated steam and hot water in the boiler to a relatively high parameter, and then sending electricity through a conventional steam turbine generator set, yet The literature on the use of high temperature heat generation from blast furnace slag and other metallurgical slags has been reported.

At present, the waste slag discharged from the blast furnace at home and abroad is water quenched to form water quenching slag, and the generated water quenching slag is used for the mixture of cement production. The steam after water quenching causes environmental pollution and serious waste of water, especially high. The high-temperature heat of the slag is wasted and not used properly, which brings huge losses to the enterprise.

Summary of the invention

The first technical problem to be solved by the present invention is to provide a method of generating electricity using blast furnace slag heat. The method is to use the heat of the slag discharged from the blast furnace iron to burn the mixture in the chain grate boiler to generate steam, to promote the steam turbine to generate electricity, and the cooled slag can be used as a clinker for producing cement. Recycling the high-temperature heat energy of blast furnace slag can greatly reduce the production cost of iron making, reduce energy consumption and power consumption, and reduce environmental pollution.

Another technical problem to be solved by the present invention is to provide an apparatus for generating heat using slag slag heat. In order to solve the above first technical problem, the present invention provides a method for generating electricity by using blast furnace slag heat, which comprises the following steps:

1) pouring the molten slag in a molten state into a slag bag having a heat insulating effect to maintain the molten state of the blast furnace slag; 2) Adjusting the position of the quenching burner, allowing the blast furnace slag to flow uniformly from the slag bag vertically into the wind quenching chamber, and the hot air from the wind quenching fan is injected into the wind quenching chamber along the tangential line through the air duct, 'in the air quenching The whirlwind is formed in the room, and the blast furnace blasts the blast furnace slag into small particles, and the small particles are further broken into small particles of 0.5-8 mm under the action of high-speed rotating impeller under the wind quenching chamber. The impeller speed is 300 rpm to 2500 rpm;

3) using the pressurized slag hot air blower to send the falling fine particles together with the air into the slag bin of the chain grate boiler, and then into the grate of the boiler; the coal bunker of the chain grate boiler is added to the coal bunker. Coal is placed on the grate in the boiler; lime powder is added to the grate in the boiler through the lime silo inlet of the chain grate boiler; the lime powder is added to supplement the calcium and sulfur of the blast furnace slag to approximate the chemical composition of the cement clinker. Thereby increasing the hydration activity and strength of the ash discharged from the chain grate type boiler; the specific weight distribution is as follows: blast furnace slag particles are 65~90%, coal burning is 5~25%, lime powder is 5~25%; It is impossible to make 95% of the blast furnace slag particles. It is obvious that when it accounts for 95%, the other two raw materials take up the minimum value of more than 100%.) The blast furnace slag, coal-fired and lime powder mixture is 800~130 (TC burns at high temperature, emits heat, generates steam to promote the operation of the condensing steam turbine, and promotes the power generation of the steam turbine generator; the ash after the combustion reaction is sent out of the furnace by the grate, and after water quenching, becomes a phase composition and Chemical formation In order to solve the above second technical problem, the present invention provides a device for generating electricity by using blast furnace slag heat, which comprises a slag furnace package, an air quenching system, a pressurized slag blowing fan, and Chain grate type boiler;

An air quenching system is disposed directly under the slag furnace package, and the air quenching system includes a wind quenching chamber, an air quenching nozzle, an impeller, and an air quenching and pressing fan, and the wind quenching and pressing fan sends air into the wind pipe through the tangential direction of the air duct. a quenching chamber; the wind quenching nozzle is disposed at an upper portion of the quenching chamber, and the impeller is disposed at a lower portion of the quenching chamber;

The pressurized slag blower includes a body and a slag supply pipe, and a bottom end outlet of the wind quenching chamber is connected to a slag supply pipe of the pressurized slag blower;

a slag bin, a coal bunker and a lime silo are fixed on the chain grate type boiler, and an outlet of the slag pipe of the pressurized slag blower is connected with the slag bin; the bottom of the boiler is provided with a grate. The blast furnace slag, coal and lime chambers are burned together on the grate, and the generated steam powers the generator set.

The beneficial effects of the invention are as follows: the heat energy of the blast furnace slag is recovered to maximize power generation, which saves energy for the society, thereby reducing the energy consumption and power consumption of the steel plant, reducing the cost of ironmaking, and improving the steel plant. Economic and social benefits. At the same time, the ash after combustion of the blast furnace slag becomes a cement clinker with excellent performance and good hydration activity.

DRAWINGS

The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

1 is a flow chart of a method for generating electricity by using slag slag heat according to the present invention;

2 is a device for generating electricity using blast furnace slag heat according to the present invention.

detailed description

Example 1

Referring to FIG. 2, the present invention provides a device for generating electricity by using slag slag heat, which comprises a smelting furnace package 1, an air quenching system 2, a pressurized slag blowing fan 3, and a chain grate type boiler 4;

An air quenching system 2 is disposed directly below the slag furnace package 1. The air quenching system 2 includes a quenching chamber 21, an air quenching nozzle 22, an impeller 23, and an air quenching and pressing fan 24, and the wind quenching and pressing fan 24 passes The air duct 25 sends air into the wind quenching chamber 21 in the tangential direction; the wind quenching nozzle 22 is disposed at an upper portion of the quenching chamber 21, and the impeller 23 is disposed at a lower portion of the quenching chamber 21;

The pressurized slag blower 3 includes a body 31 and a slag supply pipe 32, and the bottom end outlet of the wind quenching chamber 21 is connected to the slag supply pipe 32 of the pressurized slag blower 3;

A slag silo 41, a coal bunker 42 and a lime silo 43 are fixedly arranged above the chain grate type boiler 4, and an outlet of the slag supply pipe 32 of the pressurized slag blower 3 is connected to the slag bin 41; the boiler The middle portion of 4 is provided with a grate 44 which is burned together on the grate together with the blast furnace slag, which produces steam to power the generator set.

Referring to Figures 1 and 2, a method for generating electricity by using blast furnace slag heat includes the following steps: 1) Pour blast furnace slag 5 in a molten state into a slag package 1 having a heat preservation effect to maintain blast furnace slag. Molten state

2) Adjusting the position of the air quenching nozzle 22, allowing the blast furnace slag 5 to flow uniformly from the slag bag 1 vertically downward into the air quenching chamber 21, and the hot air from the air quenching and pressing fan 24 is injected into the wind quenching chamber along the tangential line through the air duct. 21, a cyclone is formed in the quenching chamber 21, and the cyclone blasts the blast furnace slag which has flowed down into small particles, and the small particles are broken under the action of the high-speed rotating impeller 23 disposed under the quenching chamber 21, further breaking the small particles a fine particle of 0.5-8 mm, the impeller speed is 300 rpm;

3) Using the pressurized slag hot air blower 3 to send the falling fine particles together with the air to the chain grate boiler 4 into the slag bin, and then added to the grate 44 in the boiler; through the coal bunker of the chain grate boiler 4 to join the coal into the grate 44 in the boiler 4; through the lime silo 43 inlet of the chain grate boiler 4 The lime powder is added to the grate 44 in the boiler, and the lime powder is added to supplement the calcium and sulfur of the blast furnace slag to approach the chemical composition of the cement clinker, thereby improving the hydration activity of the ash discharged from the chain grate boiler 4 and Strength; specific weight distribution is as follows: blast furnace slag particles are 65%, coal is 25%, lime powder is 10%; the slag, coal and lime powder mixture 45 is burned at 800 Ό high temperature, releasing heat, Steam is generated to drive the condensing steam turbine to drive the steam turbine generator to generate electricity; the ash ash 46 after the combustion reaction is sent out of the furnace by the grate 44, and after water quenching, it becomes a phase composition and chemical composition is very similar to the cement clinker. Approximate quality cement raw materials.

Example 2

Repeat Example 1, which differs in:

Referring to Figures 1 and 2, the present invention provides a method for generating electricity using blast furnace slag heat, comprising the following steps:

1) Pour the blast furnace slag 5 in a molten state into a slag package 1 having a heat insulating effect, and maintain the molten state of the blast furnace slag;

2) Adjusting the position of the air quenching nozzle 22, the blast furnace slag 5 is uniformly flowed vertically downward from the slag bag 1 into the air quenching chamber 21, and the hot air from the air quenching and pressing fan 24 is injected into the wind quenching chamber along the tangential line through the air duct. 21, a cyclone is formed in the quenching chamber 21, and the cyclone blasts the blast furnace slag which has flowed down into small particles, and the small particles are broken under the action of the high-speed rotating impeller 23 disposed under the quenching chamber 21, further breaking the small particles 1 to 8 mm of fine particles, the impeller speed is 1000 rpm;

3) using the pressurized slag hot air blower 3 to send the fallen fine particles together with the air into the slag bin of the chain grate boiler 4, and then added to the grate 44 in the boiler; through the chain grate boiler 4 The coal bunker is added to the grate 44 of the boiler 4; the lime powder is added to the grate 44 of the boiler through the inlet of the lime silo 43 of the chain grate boiler 4, and the lime powder is added for calcium and sulfur fixation of the grate furnace slag. Close to the chemical composition of the cement clinker, thereby improving the hydration activity and strength of the ash discharged from the chain grate boiler 4; the specific weight distribution is as follows: 90% of the blast furnace slag particles, 5% of the coal combustion, and the lime powder is 5%; the blast furnace slag, coal-fired and lime powder mixture 45 is fired at 1000 Ό high temperature, releasing heat, generating steam to promote the operation of the condensing steam turbine, thereby driving the steam turbine generator to generate electricity; the ash slag 46 after the combustion reaction is The row 44 is sent out of the furnace, and after water quenching, it becomes a high-quality cement raw material whose phase composition and chemical composition are very similar to cement clinker. Example 3

Repeat Example 1, which differs in:

2) Adjusting the position of the air quenching nozzle 22, the blast furnace slag 5 is uniformly flowed vertically downward from the slag bag 1 into the air quenching chamber 21, and the hot air from the air quenching and pressing fan 24 is injected into the wind quenching chamber along the tangential line through the air duct. 21, a cyclone is formed in the quenching chamber 21, and the cyclone blasts the blast furnace slag which has flowed down into small particles, and the small particles are broken under the action of the high-speed rotating impeller 23 disposed under the quenching chamber 21, further breaking the small particles 1 to 8 mm of fine particles, the impeller speed is 1800 rpm;

3) using the pressurized slag hot air blower 3 to send the fallen fine particles together with the air into the slag bin of the chain grate boiler 4, and then added to the grate 44 in the boiler; through the chain grate boiler 4 The coal bunker is added to the grate 44 of the boiler 4; the lime powder is added to the grate 44 of the boiler through the inlet of the lime silo 43 of the chain grate boiler 4, and the lime powder is added for calcium and sulfur fixation of the blast furnace slag. Close to the chemical composition of the cement clinker, thereby improving the hydration activity and strength of the ash discharge from the chain grate boiler 4; the specific weight distribution is as follows: 70% of the blast furnace slag particles, 5% of the coal combustion, and the lime powder is 25%; the blast furnace slag, coal-fired and lime powder mixture 45 is ignited and burned at a high temperature of 1100 ° C, releasing heat, generating steam to promote the operation of the condensing steam turbine, thereby driving the steam turbine generator to generate electricity; and burning the ash after the reaction 46 The grate is sent out from the grate 44, and after water quenching, it becomes a high-quality cement raw material whose phase composition and chemical composition are very similar to cement clinker.

Example 4

Repeat Example 1, which differs in:

1) pouring the molten slag 5 into a slag package 1 having a heat insulating effect to maintain the molten state of the blast furnace slag;

2) Adjusting the position of the air quenching nozzle 22, the blast furnace slag 5 is uniformly flowed vertically downward from the slag bag 1 into the air quenching chamber 21, and the hot air from the air quenching and pressing fan 24 is injected into the wind quenching chamber along the tangential line through the air duct. 21, a cyclone is formed in the quenching chamber 21, and the cyclone blasts the blast furnace slag which has flowed down into small particles, and the small particles are broken under the action of the high-speed rotating impeller 23 disposed under the quenching chamber 21, further breaking the small particles Into one 8mm fine particles, the impeller speed is 2500 rpm;

3) using the pressurized slag hot air blower 3 to send the fallen fine particles together with the air into the slag bin of the chain grate boiler 4, and then added to the grate 44 in the boiler; through the chain grate boiler 4 The coal bunker is added to the grate 44 of the boiler 4; the lime powder is added to the grate 44 of the boiler through the inlet of the lime silo 43 of the chain grate boiler 4, and the lime powder is added for calcium and sulfur fixation of the blast furnace slag. Close to the chemical composition of the cement clinker, thereby improving the hydration activity and strength of the ash discharge from the chain grate boiler 4; the specific weight distribution is as follows: 77% of the blast furnace slag particles, 13% of the coal combustion, and the lime powder is 10%; the blast furnace slag, coal-fired and lime powder mixture 45 is fired at 130 (TC high temperature, releasing heat, generating steam to promote the operation of the condensing steam turbine, thereby driving the steam turbine generator to generate electricity; burning the ash after the reaction 46 The grate is sent out from the grate 44, and after water quenching, it becomes a high-quality cement raw material having a phase composition and a chemical composition very similar to cement clinker. Obviously, the above embodiment of the present invention is only for clarity. The examples of the present invention are not limited to the embodiments of the present invention, and other variations or modifications of the various forms may be made by those skilled in the art based on the above description. All of the embodiments are exhaustive, and obvious variations or modifications which are obvious to those skilled in the art are still within the scope of the invention.

Claims

A method for generating electricity by using blast furnace slag heat, characterized in that it comprises the following steps:

1) pouring the blast furnace slag in a molten state into a slag bag having a heat insulating effect to maintain the molten state of the blast furnace slag;

2) Adjusting the position of the quenching burner, allowing the blast furnace slag to flow uniformly from the slag bag vertically into the wind quenching chamber, and the hot air from the wind quenching fan is injected into the wind quenching chamber along the tangential line through the air duct, in the wind quenching chamber Forming a cyclone, the cyclone blasts the blast furnace slag into small particles, and the small particles are further broken into small particles of 0.5-8 mm under the action of high-speed rotating impeller under the wind quenching chamber, The impeller speed is 300 rev / min ~ 2500 rev / min;

3) using the pressurized slag hot air blower to send the falling fine particles together with the air into the slag bin of the chain grate boiler, and then added to the grate in the boiler; the coal bunker of the chain grate boiler is added to the coal bunker Coal to the grate in the boiler; adding lime powder to the grate in the boiler through the lime silo inlet of the chain grate boiler; adding lime powder is to add calcium and sulfur to the blast furnace slag to approach the chemical composition of the cement clinker, Thereby increasing the hydration activity and strength of the ash slag discharged from the chain grate type boiler; the specific weight distribution is as follows: blast furnace slag particles are 65~90%, coal burning is 5~25%, lime powder is 5~25%; The blast furnace slag, coal-fired and lime powder mixture is ignited and burned at a high temperature of 800~1300 °C, releasing heat, generating steam to promote the operation of the condensing steam turbine, thereby promoting the steam turbine generator to generate electricity.

2. A device for generating electricity by using blast furnace slag heat, characterized in that it comprises a slag furnace package, a wind quenching system, a pressurized slag blowing fan and a chain grate type boiler;

The chain grate type boiler is fixed with a slag bin, a coal bunker and a lime silo, and the outlet of the slag pipe of the pressurized slag blower is connected with the slag bin; the middle of the boiler is provided with a grate.