阅读说明：本技术 一种用于控制igcc气化炉堵渣的操作方法 (Operation method for controlling slag blockage of IGCC gasification furnace ) 是由 吴平 秦建明 祁海鹏 艾云涛 王相平 李志强 孙国平 王超 许冬亮 贾东升 付彬 于 2020-12-21 设计创作，主要内容包括：本发明公开了一种用于控制IGCC气化炉堵渣的操作方法,包括如下步骤：严格关注入炉煤成分、灰熔点变化,分析其可能造成的影响,关注低温共熔体对气化炉稳定运行的影响；密切关注气化炉运行主要参数变化,及时调整运行工况；AGC运行条件下,因负荷变动的不确定性以及监测数据延后性的特点,根据情况选择退出AGC运行,待确定气化炉运行稳定后再投入AGC；操作人员需要加强培训,避免在操作过程中出现操作失误而造成堵渣；通过“气顶破渣法”和“水顶破渣法”在气化炉堵渣时进行破渣。减小了三种不同的堵渣情况的发生频次,IGCC机组安全稳定运行可靠性得到大为增强,减少了机组非停次数；堵渣后,对气化炉进行快速、安全破渣,保障气化炉的稳定运行。(The invention discloses an operation method for controlling slag blockage of an IGCC gasification furnace, which comprises the following steps: strictly paying attention to the change of the components and ash melting points of the coal as fired, analyzing the influence possibly caused by the change, and paying attention to the influence of the low-temperature co-melting body on the stable operation of the gasification furnace; closely paying attention to the change of main operating parameters of the gasification furnace and adjusting the operating condition in time; under the AGC operation condition, selecting to quit AGC operation according to the condition due to the uncertainty of load change and the characteristics of monitoring data delay, and putting in AGC after the gasification furnace is determined to operate stably; the training of operators is required to be strengthened, and slag blockage caused by misoperation in the operation process is avoided; the slag is broken through a gas cap slag breaking method and a water cap slag breaking method when the gasification furnace blocks slag. The occurrence frequency of three different slag blocking situations is reduced, the safe and stable operation reliability of the IGCC unit is greatly enhanced, and the non-stop times of the unit are reduced; after slag blockage, the gasifier is rapidly and safely broken, and stable operation of the gasifier is guaranteed.)

1. An operation method for controlling slag blockage of an IGCC gasification furnace is characterized by comprising the following steps:

s1, operation prevention

S101, strictly paying attention to the composition and ash melting point changes of coal as fired, analyzing possible influences caused by the coal as fired, and adjusting coal quality components before the coal powder is fired according to the operation condition of the gasification furnace; when the ash melting point is more than 1260 ℃, paying attention to the influence of the low-temperature eutectic body on the stable operation of the gasification furnace;

s102, closely paying attention to the change of main operating parameters of the gasification furnace, adjusting the operating condition in time, and stabilizing the safe operation of the gasification furnace by lifting the load under the condition of departing from the AGC operation;

s103, under the AGC operation condition, selecting to quit AGC operation according to the situation due to the uncertainty of load change and the characteristics of monitoring data delay, and putting in AGC after the gasification furnace is determined to operate stably;

s104, training is required to be strengthened for operators, and slag blockage caused by misoperation in the operation process is avoided;

s2, slag blockage treatment

S201, adopting a 'gas cap slag breaking method' when the bottom of the ash collecting tank (2) blocks slag, namely isolating the ash collecting tank (2) and the ash discharging tank (3), and breaking the blocked slag through high-pressure nitrogen gas;

s202, a water top slag breaking method is adopted when slag is blocked between the ash residue collecting tank (2) and the ash residue discharging tank (3) or the bottom of the ash residue discharging tank (3), namely the ash residue collecting tank (2) and the ash residue discharging tank (3) are isolated, a circulating pump (7) is switched to self circulation, and high-pressure circulating water is used for flushing the blocked slag.

2. The operation method for controlling slag blockage of the IGCC gasification furnace according to claim 1, characterized in that: in step S101, the method for adjusting coal components includes adding limestone and fly ash before feeding pulverized coal into a gasifier, where the ratio of limestone is 0.5%, the low-temperature eutectic is a eutectic formed by sodium oxide and potassium oxide and oxides in coal ash, and when an ash melting point is greater than 1260 ℃, stabilizing an operation condition in the gasifier by adjusting an oxygen-coal ratio.

3. The operation method for controlling slag blockage of the IGCC gasification furnace according to claim 1, characterized in that: in step S102, the main operating parameters of the gasification furnace comprise steam-water mixture density change, furnace temperature change and ash meltability change, the steam-water mixture density has hysteresis, the density change range is kept between 660-710 kg-m 3, rapid temperature rise and temperature reduction are avoided, and severe change of the operating condition in the furnace is prevented, so that operators are misled.

4. The operation method for controlling slag blockage of the IGCC gasification furnace according to claim 1, characterized in that: in step S103, when the load change is larger than 4h, the monitoring data is serious, the pre-anti-blocking slag is operated in advance to have certain risk, the AGC operation is quitted, the parameter change in a period of time is observed, and the load is put into the AGC to continue to lift and control the load after the working condition is stable.

5. The operation method for controlling slag blockage of the IGCC gasification furnace according to claim 1, characterized in that: in the step S201, the 'air-cap slag breaking method' is to isolate an ash collecting tank (2) and an ash discharging tank (3), open a valve of a high-pressure nitrogen pipe (5) at the top of the ash discharging tank (3), improve the pressure difference of the two tanks, then communicate the two tanks, normally operate a circulating pump (7), break slag from bottom to top, observe whether the flow of circulating grey water is normal or not, and if so, successfully break the slag; otherwise, repeating the operation and increasing the pressure difference until the slag breaking is successful.

6. The operation method for controlling slag blockage of the IGCC gasification furnace according to claim 1, characterized in that: in the step S202, the water top slag breaking method is to isolate an ash collecting tank (2) and an ash discharging tank (3), a circulating pump (7) is switched to self-circulation, a high-pressure circulating water pipe (4) at the bottom of the ash discharging tank (3) is used for replenishing water to the tanks, the pressure difference of the two tanks is improved, then the two tanks are communicated, the slag is broken by utilizing the incompressibility of water, whether the circulating ash water is recovered normally or not is observed, and if the circulating ash water is recovered normally, the slag is broken successfully; otherwise, repeating the operation and increasing the pressure difference between the two tanks until the slag breaking is successful.

7. The operation method for controlling slag blockage of the IGCC gasification furnace according to claim 1, characterized in that: slag bath (1) is connected at the top of lime-ash collection tank (2), lime-ash discharge tank (3) is connected to the bottom of lime-ash collection tank (2), the circulating pipe at lime-ash discharge tank (3) top is connected with slag extractor (6), the circulating pipe of slag bath (1) department is connected with circulating water cooler (8).

Technical Field

The invention relates to the technical field of IGCC gasification furnaces, in particular to an operation method for controlling slag blockage of an IGCC gasification furnace.

Background

Through IGCC practical production experience for many years, three types of slag blockage accidents are summarized by combining the operation working conditions of the gasification furnace: static slag blocking, dynamic slag blocking and slag blocking under AGC operation conditions.

Static slag blocking: under the condition that the operation working condition of the gasification furnace is relatively stable, the combustion state in the furnace is relatively stable, the slag adhering is good, and the slag blocking probability is low. However, due to the complexity of coal itself, although the Shenfu Dongsheng coal field is used as a single coal for combustion, the coal quality of different coal entering the factory still has slight differences. After the coal as fired changes in coal quality components, the relatively stable working conditions in the gasification furnace may change due to the change of the coal quality components, and if the coal is not processed in time, the accidents of slag blockage or equipment burnout may be caused.

Dynamic slag blocking: because the temperature of the gasification furnace is low, an operator avoids slag blockage caused by thick slag layer due to low furnace temperature and slag blockage caused by slag collapse due to too fast manual temperature rise.

Slag blockage under AGC operation conditions: after the unit is put into AGC operation, the unit operation state is changed continuously, in the process of large-amplitude load lifting, the fluctuation of the unit operation state influences the gasification furnace, slag blocking is easy to occur, and at present, slag blocking cannot be effectively prevented and slag is broken well after slag blocking, so that an operation method for controlling slag blocking of the IGCC gasification furnace is provided for solving the problems.

Disclosure of Invention

The invention aims to provide an operation method for controlling the slag blockage of an IGCC gasification furnace, so as to solve the problems in the background technology.

In order to achieve the purpose, the invention provides the following technical scheme: an operation method for controlling slag blockage of an IGCC gasification furnace comprises the following steps:

s1, operation prevention

S101, strictly paying attention to the composition and ash melting point changes of coal as fired, analyzing possible influences caused by the coal as fired, and adjusting coal quality components before the coal powder is fired according to the operation condition of the gasification furnace; when the ash melting point is more than 1260 ℃, paying attention to the influence of the low-temperature eutectic body on the stable operation of the gasification furnace;

s102, closely paying attention to the change of main operating parameters of the gasification furnace, adjusting the operating condition in time, and stabilizing the safe operation of the gasification furnace by lifting the load under the condition of departing from the AGC operation;

s103, under the AGC operation condition, selecting to quit AGC operation according to the situation due to the uncertainty of load change and the characteristics of monitoring data delay, and putting in AGC after the gasification furnace is determined to operate stably;

s104, training is required to be strengthened for operators, and slag blockage caused by misoperation in the operation process is avoided;

s2, slag blockage treatment

S201, adopting a 'gas cap slag breaking method' when the bottom of the ash residue collecting tank is blocked, namely isolating the ash residue collecting tank and the ash residue discharging tank, and breaking the blocked slag by high-pressure nitrogen gas;

s202, a water top slag breaking method is adopted when slag is blocked between the ash residue collecting tank and the ash residue discharging tank or at the bottom of the ash residue discharging tank, namely the ash residue collecting tank and the ash residue discharging tank are isolated, a circulating pump is switched to self circulation, and high-pressure circulating water is used for flushing and breaking the blocked slag.

In a preferred embodiment, in step S101, the method for adjusting coal quality components includes adding limestone and fly ash into the pulverized coal before the pulverized coal is charged into the gasifier, where the ratio of the limestone is 0.5%, the low-temperature eutectic is a eutectic formed by sodium oxide and potassium oxide and oxides in the coal ash, and when the ash melting point is greater than 1260 ℃, stabilizing the operation condition in the gasifier by adjusting the oxygen-coal ratio.

In a preferred embodiment, in step S102, the main operating parameters of the gasification furnace include density variation of the steam-water mixture, furnace temperature variation and ash melting variation, the density of the steam-water mixture has hysteresis, and the density variation range is kept between 660 and 710kg · m3, so as to avoid rapid temperature rise and temperature reduction, and prevent the operator from being misled due to severe variation of the operating conditions in the furnace.

In an preferable embodiment, in step S103, when the load change is greater than 4 hours, the monitoring data is serious, the pre-operation of pre-anti-clogging slag has a certain risk, at this time, the AGC operation is exited, the parameter change within a period of time is observed, and the load is put into the AGC to continue to lift and control the load after the working condition is stable.

In a preferred embodiment, in step S201, the "gas cap slag breaking method" is to isolate the ash collecting tank and the ash discharging tank, open a valve of a high-pressure nitrogen pipe at the top of the ash discharging tank, increase the pressure difference between the two tanks, then connect the two tanks, normally operate a circulating pump, break the ash from bottom to top, observe whether the circulating grey water flow returns to normal, and if normal, successfully break the ash; otherwise, repeating the operation and increasing the pressure difference until the slag breaking is successful.

In a preferred embodiment, in step S202, the "water top slag breaking method" is to isolate the ash collecting tank and the ash discharging tank, the circulating pump is switched to self-circulation, a high-pressure circulating water pipe at the bottom of the ash discharging tank is used to replenish water into the tanks, so as to increase the pressure difference between the two tanks, and then the two tanks are communicated, so as to break slag by using the incompressibility of water, and observe whether the circulating ash water returns to normal, and if so, the slag breaking is successful; otherwise, repeating the operation and increasing the pressure difference between the two tanks until the slag breaking is successful.

In an embodiment, the top of the ash collecting tank is connected with a slag pool, the bottom of the ash collecting tank is connected with an ash discharging tank, a circulating water pipe at the top of the ash discharging tank is connected with a slag extractor, and a circulating water pipe at the slag pool is connected with a circulating water cooler.

Compared with the prior art, the invention has the beneficial effects that:

1. the occurrence frequency of three different slag blocking situations is reduced, the safe and stable operation reliability of the IGCC unit is greatly enhanced, and the non-stop times of the unit are reduced;

2. after slag is accidentally blocked, the gasification furnace is rapidly and safely broken by adopting a water top slag breaking method and a gas top slag breaking method according to the slag blocking condition, so that the stable operation of the gasification furnace is ensured;

3. the method is simple and easy to implement, and has popularization prospect and value.

Drawings

FIG. 1 is a schematic view of the structure of the present invention.

In the figure: 1. a slag pool; 2. an ash collecting tank; 3. an ash discharge tank; 4. a high-pressure circulating water pipe; 5. a high-pressure nitrogen pipe; 6. a slag extractor; 7. a circulation pump; 8. a circulating water cooler.

Detailed Description

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

Referring to fig. 1, the present invention provides a technical solution: an operation method for controlling slag blockage of an IGCC gasification furnace comprises the following steps:

s1, operation prevention

S101, strictly paying attention to the composition and ash melting point changes of coal as fired, analyzing possible influences caused by the coal as fired, and adjusting coal quality components before the coal powder is fired according to the operation condition of the gasification furnace; when the ash melting point is more than 1260 ℃, paying attention to the influence of the low-temperature eutectic body on the stable operation of the gasification furnace;

s102, closely paying attention to the change of main operating parameters of the gasification furnace, adjusting the operating condition in time, and stabilizing the safe operation of the gasification furnace by lifting the load under the condition of departing from the AGC operation;

s103, under the AGC operation condition, selecting to quit AGC operation according to the situation due to the uncertainty of load change and the characteristics of monitoring data delay, and putting in AGC after the gasification furnace is determined to operate stably;

s104, training is required to be strengthened for operators, and slag blockage caused by misoperation in the operation process is avoided;

s2, slag blockage treatment

S201, adopting a 'gas cap slag breaking method' when the bottom of the ash collecting tank 2 is blocked, namely isolating the ash collecting tank 2 and the ash discharging tank 3, and breaking the blocked slag by high-pressure nitrogen;

s202, a 'water top slag breaking method' is adopted when slag is blocked between the ash collecting tank 2 and the ash discharging tank 3 or the bottom of the ash discharging tank 3, namely the ash collecting tank 2 and the ash discharging tank 3 are isolated, the circulating pump 7 is switched to self-circulation, and high-pressure circulating water is used for flushing and breaking the blocked slag.

In step S101, the method for adjusting coal quality components includes adding limestone and fly ash into pulverized coal before the pulverized coal is charged into a furnace, where the ratio of limestone is 0.5%, and the low-temperature eutectic is a eutectic formed by sodium oxide and potassium oxide and oxides in the coal ash, stabilizing the operating condition in the gasifier by adjusting the ratio of oxygen to coal when the ash melting point is greater than 1260 ℃, and in the actual operating process, according to the selection of the operating condition when limestone is subsequently added to the charged coal, the small change of the single coal type coal ash component can cause the change of the operating condition of the gasifier, and the accident of preventing slag blockage can be effectively prevented by adjusting the ratio of oxygen to coal and adding limestone.

In step S102, the main operating parameters of the gasification furnace include steam-water mixture density change, furnace temperature change and ash meltability change, the steam-water mixture density has hysteresis, the density change range is kept between 660-710 kg.m 3, rapid temperature rise and temperature reduction are avoided, and the phenomenon that the operating condition in the furnace changes violently and operators are misguided is prevented.

Further, in step S103, when the load change is greater than 4 hours, the monitoring data is strong, the pre-plugging prevention slag is operated in advance, and a certain risk exists, at this time, the AGC operation is exited, the parameter change within a period of time is observed, and the load is input into the AGC to continue to control the load in a lifting manner after the working condition is stable.

Further, in step S201, the "gas cap slag breaking method" is to isolate the ash collecting tank 2 and the ash discharging tank 3, open the valve of the high pressure nitrogen pipe 5 on the top of the ash discharging tank 3, increase the pressure difference between the two tanks, then connect the two tanks, normally operate the circulating pump 7, break the slag from bottom to top, observe whether the circulating grey water flow returns to normal, if normal, the slag breaking is successful; otherwise, repeating the operation and increasing the pressure difference until the slag breaking is successful.

Further, in step S202, the "water top slag breaking method" is to isolate the ash collecting tank 2 and the ash discharging tank 3, the circulating pump 7 is switched to self-circulation, the high-pressure circulating water pipe 4 at the bottom of the ash discharging tank 3 is used for replenishing water to the tanks, so as to increase the pressure difference between the two tanks, then the two tanks are communicated, the slag is broken by using the incompressibility of water, whether the circulating ash water is recovered to normal or not is observed, and if the circulating ash water is recovered to normal, the slag breaking is successful; otherwise, repeating the operation and increasing the pressure difference between the two tanks until the slag breaking is successful.

Further, slag bath 1 is connected at the top of lime-ash collection tank 2, and lime-ash discharge tank 3 is connected to the bottom of lime-ash collection tank 2, and the circulating pipe at 3 tops of lime-ash discharge tank is connected with slag extractor 6, and the circulating pipe of 1 department in slag bath is connected with circulating water cooler 8.

The working principle is as follows: the method analyzes the possible influence by closely paying attention to the change of the components and the ash melting point of the coal as fired, adds limestone, fly ash and the like into the coal before the coal powder is fired according to the operation working condition of the gasification furnace to adjust the coal components, and pays attention to the influence of the possible generated low-temperature co-melting body on the stable operation of the gasification furnace when the ash melting point is more than 1260 ℃; closely paying attention to the change of main operating parameters of the gasification furnace, adjusting the operating condition in time, and stabilizing the safe operation of the gasification furnace by lifting the load under the condition of departing from the AGC operation; under the AGC operation condition, selecting to quit AGC operation according to the condition due to the uncertainty of load change and the characteristics of monitoring data delay, and putting in AGC after the gasification furnace is determined to operate stably; the operation personnel need to be trained intensively, slag blockage caused by misoperation in the operation process is avoided, the frequency of three different slag blockage situations is reduced, the safety and stable operation reliability of the IGCC unit is greatly enhanced, the non-stop times of the unit are reduced, and after accidental slag blockage, the gasification furnace is rapidly and safely cracked by adopting a water top slag cracking method and a gas cap slag cracking method according to the slag blockage situations, so that the stable operation of the gasification furnace is ensured.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.