Should the black water from the gasification start-up be routed to the flash system at the required pressure?
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Dear teachers, at the start of gasification, the system pressure is required to be raised to 1.0 Mpa in order to divert the black water from the gasifier to the high-flash tank; at 1.5 Mpa, the black water from the cyclone separator and the carbon scrubber is diverted to the high-flash tank as well. May I ask why there is such pressure to meet these requirements? Can it be cut at a higher pressure?
It depends on your layout – if the high-gloss area is at a high position, and less than 10 kilograms of material have been added yet, water won’t be able to get there. Or in some cases, the high flash point is listed first, the low flash point is higher than the high one, and the true flash point is higher than the low flash point; as a result, when the high flash point is ranked first, there is no pressure difference, and the black water doesn’t flow, leading to blockages.
The water cutting pressure you have is quite high; we use 5 kilograms for gasification furnaces, and 8 kilograms for cyclones and scrubbers.
The valve opening and closing pressure difference is determined based on the pressure rating of the black water coolers and pipes during startup. During operation, problems may arise with the ash water treatment system, which leads to a reduction in the furnace’s load and the diversion of black water to the startup process.
First is the issue of pressure differences and pressure while driving, which prevents water from being drained; second is preventing the accumulation of scale caused by pressure fluctuations, thus avoiding blockages
It is primarily determined by the pressure difference before and after the high flash angle valve, as well as the requirements related to the removal of scale particles from the pipes after the system is brought online. Generally, during startup, the high flash angle valve is kept fully open; once pressure builds up and water starts flowing, the valve is closed, allowing the system pressure to increase