Gasification furnace lock hopper slag flushing water recycling system

Abstract

The invention provides a gasification furnace lock hopper slag flushing water recycling system. The system comprises a gasification furnace, and the gasification furnace is connected with a lock hopper through a pipeline. The lock hopper is connected with a submerged chain conveyor through a pipeline. The submerged chain conveyor is connected with an inlet of a slag pool pump through a pipeline, and an outlet of the slag pool pump is connected with a first flow regulating valve and a second flow regulating valve through pipelines respectively. The first flow regulating valve is connected witha lock hopper flushing water tank through a pipeline, and the lock hopper flushing water tank is connected with the lock hopper through a pipeline. The second flow regulating valve is connected with avacuum flash tank through a pipeline, the vacuum flash tank is connected with a clarification tank through a pipeline, and the clarification tank is connected with a grey water tank through a pipeline. Through graded utilization of water of different qualities, the black water circulation amount of the system is reduced, the operation costs of chemicals and circulating water and the electric charge are reduced, and the problem that a valve is difficult to open and close due to scaling of a slag flushing pipeline of the lock hopper and the problem that timing deslagging of the lock hopper is affected due to insufficient water supplementation are solved.

Description

technical field [0001] The invention provides a system for recycling slag flushing water in a gasifier, belonging to the technical field of recycling slag flushing water in a coal-water slurry gasification process. Background technique [0002] The ash and slag produced by the reaction between the oxygen and the coal-water slurry in the entrained-bed coal-water paddle gasifier are discharged through the lock bucket system, and then taken out and transported out by the slag scraper. In the existing lock-bucket flushing water replenishment process of the gasifier, all the slag flushing water in the lock-bucket flushing tank is hydraulically flushed and then pumped to the vacuum flash tank, where the black water flashes through the vacuum flash tank. After that, the slag washing water and black water are mixed through the clarification tank to reduce the solid content, add scale inhibitor and enter the gray water tank, pressurized again by the pump, cooled by the heat exchanger...

AI Technical Summary

Problems solved by technology

In the lock bucket flushing water replenishment process of the existing gasification furnace, all the slag flushing water in the lock bucket flushing tank is used to flush the slag hydraulically, and then the slag is pressurized by the pump and transported to the vacuum flash tank, and the black water flashed through the vacuum flash tank Finally, the slag flushing water and black water are mixed through the clarification tank to reduce the solid content, and the antiscalant is added to enter the gray water tank, pressurized again by the pump, cooled by the heat exchanger, and returned to the gasifier lock hopper to rinse the water tank for reuse. The biggest disadvantage of the process is the mixed use of two different water qualities

When the two kinds of water are used together to cause the slag flushing water to be reused, it is necessary to add scale inhibitors and repeat the use of centrifugal pumps to pressurize and circulate water to cool down, which increases operating costs.

[0004] Due to the limitations of existing gasification black water scale prevention technology, black water scaling cannot be effectively controlled. After a period of operation of the lock bucket slag water pipeline, the scaling will increase, and valve opening and closing will be difficult, and water replenishment will be insufficient, which will affect the lock bucket on time. Slagging

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