CN111154514A

CN111154514A - Recycling system for slag flushing water of gasification furnace lock hopper

Info

Publication number: CN111154514A
Application number: CN202010092543.6A
Authority: CN
Inventors: 祝贺; 朱敏; 吕传磊; 许广宇; 潘荣; 张俊先; 刘进波; 李静; 唐广军; 李琳; 戴武军; 赵岐; 赵矿生; 李耀; 宋成凯; 鲍卫娜; 傅进军; 褚夫奎; 林建斌; 方玮
Original assignee: Shandong Yankuang Guotuo Technology Engineering Co ltd
Current assignee: Shandong Yankuang Guotuo Technology Engineering Co ltd
Priority date: 2020-02-14
Filing date: 2020-02-14
Publication date: 2020-05-15

Abstract

The invention provides a gasification furnace lock bucket slag flushing water recycling system which comprises a gasification furnace, wherein the gasification furnace is connected with a lock bucket through a pipeline, the lock bucket is connected with a slag salvaging machine through a pipeline, the slag salvaging machine is connected with an inlet of a slag pool pump through a pipeline, an outlet of the slag pool pump is respectively connected with a first flow regulating valve and a second flow regulating valve through pipelines, the first flow regulating valve is connected with a lock bucket flushing water tank through a pipeline, the lock bucket flushing water tank is connected with the lock bucket through a pipeline, the second flow regulating valve is connected with a vacuum flash tank through a pipeline, the vacuum flash tank is connected with a clarifying tank through a pipeline, and the clarifying tank is connected with a grey water tank through a pipeline. The invention reduces the circulation amount of black water of the system, reduces the operating cost of medicament, circulating water and electricity charge and solves the problems of difficult valve opening and closing and insufficient water supply which influence the timing slag discharge of the lock hopper caused by the scaling of the slag flushing pipeline of the lock hopper by the graded utilization of different water qualities.

Description

Recycling system for slag flushing water of gasification furnace lock hopper

Technical Field

The invention provides a recycling system for lock bucket slag flushing water of a gasification furnace, and belongs to the technical field of recycling of lock bucket slag flushing water of a coal water slurry gasification process.

Background

And ash slag generated after the reaction of the oxygen of the entrained flow water coal slurry gasification furnace and the water coal slurry is discharged through the lock hopper system and is fished out through the slag dragging machine to be conveyed out. In the existing water replenishing process of lock bucket flushing water of a gasification furnace, slag flushing water of a lock bucket flushing water tank is adopted to hydraulically flush slag, then the slag flushing water is pressurized by a pump and conveyed to a vacuum flash tank, black water passing through the vacuum flash tank is flashed, the slag flushing water and the black water are mixed, the solid content of the slag flushing water and the black water is reduced by a clarifying tank, a scale inhibitor is added into an ash water tank, the mixture is pressurized again by the pump and cooled by a heat exchanger, and the mixture returns to the lock bucket flushing water tank of the gasification furnace for recycling, and the biggest defect of the original process.

The black water in the coal water slurry gasification process requires strict control of water scaling and accumulation of acid gas in water, and the scaling control method is to add a scale inhibition medicament, and a gas production device which produces millions tons of methanol or synthetic ammonia annually needs 800-1200 ten thousand yuan; the process for controlling the acid gas is decompression flash evaporation, and the acid gas dissolved in water is driven to escape by reducing the pressure, so that the corrosion of the carbon steel material is reduced. The slag flushing water belongs to micro-scale water quality, the temperature of the slag flushing water is low, and the dissolved acid gas accounts for about 15 percent of the circulation volume of the system; the black water belongs to the water quality with serious scaling, and the slag flushing water and the black water are mixed to become the water quality with serious scaling. When the two kinds of water are mixed for use to cause the slag flushing water to be recycled, a scale inhibitor needs to be added, and the centrifugal pump pressurization and the circulating water cooling are adopted repeatedly, so that the operation cost is increased.

Due to the limitation of the technical level of the existing gasification black water scale inhibition, the scale formation of the black water cannot be effectively controlled, the scale formation is aggravated after the slag flushing water pipeline of the lock hopper runs for a period of time, the valve is difficult to open and close, the insufficient water supplement situation occurs, and the lock hopper is influenced to discharge slag on time.

Disclosure of Invention

In order to solve the problems, the invention provides a recycling system for slag flushing water of a lock bucket of a gasification furnace, which adopts the technical scheme that:

the utility model provides a gasifier lock is fought towards sediment water reuse system, includes the gasifier, the gasifier passes through the pipeline and is connected with the lock fill, the lock is fought and is connected with the dragveyer through the pipeline, the dragveyer passes through the pipe and is connected with the access connection of sediment pond pump, the export of sediment pond pump is respectively through first flow control valve of pipe connection and second flow control valve, first flow control valve passes through the pipeline and is fought the wash water pitcher with the lock and be connected, the lock is fought the wash water pitcher and is connected with the lock fill through the pipeline, the second flow control valve passes through the pipeline and is connected with the vacuum flash tank, the vacuum flash tank passes through the pipeline and is connected with the clarification tank, the clarification.

Preferably, the slag dragging machine comprises a first slag chamber and a second slag chamber, the lock hopper is connected with the first slag chamber through a pipeline, and a baffle and a communicating pipe are arranged between the first slag chamber and the second slag chamber.

Preferably, the deslagging period of the lock hopper is 30 minutes, and each deslagging time is 2 minutes.

The invention optimizes the process flow of the system and reduces the operation steps; the circulation amount of black water to the vacuum flash tank is reduced by about 70m³The vacuum flash steam is correspondingly reduced due to the reduction of the flow of the black water, the heat is relatively reduced, and the circulating water consumption of a vacuum flash boiler is reduced by about 10 percent per hour; the agent saves about 100 ten thousand expenses each year due to the reduction of the circulation amount of black water; the invention has no heat exchanger for lock bucket flushing water, thus reducing the investment cost by about 35 ten thousand yuan; due to the optimization of the system flow, the scale of the lock hopper pipeline can be effectively prevented, and the pipeline cleaning cost and the maintenance cost of the instrument valve are reduced.

Drawings

The accompanying drawings are included to provide a further understanding of the invention.

In the drawings:

FIG. 1 is a schematic diagram of a recycling system for slag flushing water of a lock bucket of a gasification furnace.

Fig. 2 is a schematic diagram of a recycling system for slag flushing water of a lock bucket of a conventional gasification furnace.

In the figure: 1. a gasification furnace; 2. locking the bucket; 3. a slag conveyor; 301. a first slag chamber; 302. a second slag chamber; 4. a slag bath pump; 5. a first flow regulating valve; 6. a second flow regulating valve; 7. the lock bucket flushing water tank; 8. a vacuum flash tank; 9. a clarifying tank; 10. a grey water tank; 11. a lock bucket washing water pump; 12. a heat exchanger.

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.

As shown in fig. 1, a gasifier lock hopper slag flushing water recycling system comprises a gasifier 1, the gasifier 1 is connected with a lock hopper 2 through a pipeline, the lock hopper 2 is connected with a slag conveyor 3 through a pipeline, the slag conveyor 3 is connected with an inlet of a slag pool pump 4 through a pipeline, an outlet of the slag pool pump 4 is respectively connected with a first flow regulating valve 5 and a second flow regulating valve 6 through pipelines, the first flow regulating valve 5 is connected with a lock hopper flushing water tank 7 through a pipeline, the lock hopper flushing water tank 7 is connected with the lock hopper 2 through a pipeline, the second flow regulating valve 6 is connected with a vacuum flash tank 8 through a pipeline, the vacuum flash tank 8 is connected with a clarifying tank 9 through a pipeline, and the clarifying tank 9 is connected with a grey water tank 10 through a pipeline.

The slag dragging machine 3 comprises a first slag chamber 301 and a second slag chamber 302, the lock hopper 2 is connected with the first slag chamber 301 through a pipeline, a baffle and a communicating pipe are arranged between the first slag chamber 301 and the second slag chamber 302, the first slag chamber 301 and the second slag chamber 302 are separated by the baffle and communicated through the communicating pipe, slag flushing water in the first slag chamber 301 is precipitated and can flow into the second slag chamber 302 along the communicating pipe after reaching a certain liquid level. The deslagging period of the lock hopper 2 is 30 minutes, and each deslagging time is 2 minutes.

As shown in fig. 2, the working process of the prior art system is as follows: oxygen and coal water slurry are subjected to partial oxidation reaction in a combustion chamber of the gasification furnace 1, generated crude synthesis gas, slag and a small amount of incompletely reacted carbon flow downwards along a descending pipe through a slag hole at the lower part of the combustion chamber and chilling water and enter a washing and cooling chamber of the gasification furnace 1, and the crude synthesis gas is cooled in the washing and cooling chamber and then is discharged from the gasification furnace 1. The slag is cooled and solidified in the water bath of the washing and cooling chamber, is settled to the bottom of the washing and cooling chamber, is crushed by the static slag breaker, enters the lock hopper 2 by being carried by the circulating water of the lock hopper and is periodically discharged into the slag conveyor 3. The periodic deslagging of the lock hopper 2 is controlled by a lock hopper logic linkage automatic control system, each cycle period is about 30 minutes, the slag collecting time is 28 minutes, and the deslagging time is about 2 minutes.

Before slag is discharged from the lock hopper 2, the last slag of the gasification furnace 1 is basically precipitated in the first slag chamber 301 of the slag conveyor 3, water in the first slag chamber 301 is discharged into the second slag chamber 302, then the water is sent to the vacuum flash evaporator 8 through the slag bath pump 4 to be treated together with flash evaporation black water, and the slag in the first slag chamber 301 of the slag conveyor 3 is fished out and then is loaded into a slag car to be transported out.

After the black water in the vacuum flash tank 8 is flashed, the black water enters the clarifying tank 9 added with the scale inhibitor, and after the black water and particles are settled and separated, the grey water of the clarifying tank 9 automatically flows to the ash water tank 10, is conveyed to the heat exchanger 12 by the lock hopper flushing water pump 11 to be cooled, and then enters the lock hopper flushing water tank 7 according to a certain flow rate to flush the ash in the lock hopper 2.

The biggest defect of the prior art system is that the slag flushing water and the black water are mixed to use, so that the problems that the valve is difficult to open and close and the water replenishing is insufficient to influence the timing slag discharge of the lock hopper 2 caused by scaling of a slag flushing pipeline of the lock hopper 2 are caused, and the invention improves the prior art system, and the specific working process is as follows: slag generated by the gasification furnace 1 is discharged into a first slag chamber 301 of a slag conveyor 3 through a lock hopper 2, clean water after precipitation enters a second slag chamber 302, and a slag pool pump 4 is pressurized and directly conveyed to a lock hopper flushing water tank 7 through a first flow regulating valve 5 for water supplement; the other path of water is used for adjusting the liquid level of the slag pool of the slag dragging machine 3 through a second flow adjusting valve 6, part of slag water is conveyed to a vacuum flash tank 8, enters a clarifying tank 9 and is subjected to sedimentation separation of black water and particles, and the grey water of the clarifying tank 9 automatically flows to a grey water tank 10 for recycling.

After improvement, the process is simple, the operation is convenient, the graded utilization of different water qualities is realized, the black water circulation volume (15%) of the system is reduced, the addition of a scale inhibitor is reduced, and the running costs of circulating water, electricity charge and the like are reduced. The problem of the lock 2 towards the scaling of sediment pipeline cause the valve switch difficult, the moisturizing is not enough influences gasifier and arranges the sediment regularly is solved.

Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that various changes in the embodiments and/or modifications of the invention can be made, and equivalents and modifications of some features of the invention can be made without departing from the spirit and scope of the invention.

Claims

1. The utility model provides a gasifier lock fill slag flushing water reuse system which characterized in that: the device comprises a gasification furnace, the gasification furnace passes through the pipeline and is connected with the lock fill, the lock fill passes through the pipeline and is connected with the dragveyer, the dragveyer passes through the pipeline and is connected with the access connection of sediment pond pump, the export of sediment pond pump passes through first flow control valve of line connection and second flow control valve respectively, first flow control valve passes through the pipeline and is connected with the lock fill wash water pitcher, the lock fill wash water pitcher passes through the pipeline and is connected with the lock fill, the second flow control valve passes through the pipeline and is connected with vacuum flash tank, vacuum flash tank passes through the pipeline and is connected with the clarification tank, the clarification tank passes through the pipeline and is connected with.

2. The gasifier lock fill slag flushing water reuse system of claim 1, characterized in that: the slag dragging machine comprises a first slag chamber and a second slag chamber, the lock hopper is connected with the first slag chamber through a pipeline, and a baffle and a communicating pipe are arranged between the first slag chamber and the second slag chamber.

3. The gasifier lock fill slag flushing water reuse system of claim 1, characterized in that: the deslagging period of the lock hopper is 30 minutes, and each deslagging time is 2 minutes.