Still regarding the coal hopper issue__Issue updated! ! !
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This post was last edited by shanxg on 2010-11-5 09:08. As a side note: I won’t post again; I’ll just update the question to avoid any suspicion of trying to make money. . . . . . 1. I consulted relevant design firms, and they said that for furnaces of this type used for powder coal gasification, although adding a lockhopper can solve the problem of feeding under positive pressure, it only allows for intermittent feeding. As a result, the lockhopper leads to significant air leakage, a decrease in gas production, and consequently a reduction in gasification efficiency. Is that so? ? ? If so, is there a solution? 2. How is the voltage transformation – stepping up and stepping down – of the coal hopper used for feeding pulverized coal achieved? 3. The coal lockhopper is located near the furnace; gasification produces high-temperature gas, so does the material used to make the coal lockhopper need to be heat-resistant? Here are the questions that were not answered last time; I still want to get some clarity on them: 4. In catalytic reforming processes and the regeneration units for continuous reforming reactions, there is a concept called a blocked hopper. Essentially, is this different from what is commonly referred to as a coal hopper? I look forward once again to expert answers; thanks so much! !
There are two lockhoppers in pulverized coal gasification: one for the pulverized coal and another for the slag. The pulverized coal lockhopper is used for transporting coal; it is not merely a pressure vessel. Its function can be simply described as follows: pulverized coal at normal pressure is pressurized and sent to the pulverized coal feed tank, from where it enters the burner and then the gasification furnace. After that, the pressure is reduced again, allowing the coal powder from the storage tank to be received. Internal structure: flue pipes, sintered metal. The slag lockhopper is used for transporting slag; it is connected to the gasification furnace via a slag breaker. Its principle is similar to that of a coal powder lockhopper – there is a process of pressure increase and decrease. Pressure is increased to receive slag from the gasification furnace, and then reduced to send the slag to the slag pool. This cycle of pressure increase and decrease continues
Reply to 2# wangjifan88: Is the pressure increase achieved through the carrier gas (carbon dioxide or nitrogen)? So does the carrier gas eventually enter the vaporization furnace?
Reply to 4# milanac21: Only a very small portion of the gas can enter the furnace; the vast majority of the inert gas is released. After the pressure in 1204 is increased and all the coal powder has entered 1205, 1204 is isolated from 1205, and its pressure is reduced to atmospheric level so that it can receive the coal powder from 1201. The gas used for pressing in the previous cycle is released
Reply to 1# sethfly’s question 1: The gasification furnace operates with continuous feeding; the hopper is merely a device for temporarily storing pulverized coal. The device that ensures continuous feeding is the one located below the hopper, and it maintains stable pressure, thereby ensuring a steady feeding process. As for the issue of air leakage from the lock hopper, when the lock hopper releases pressure, it is essentially a process of exhaust, so air leakage is not a problem. A decline in gasification efficiency is out of the question, as it has nothing to do with the gasification reaction in this unit operation. Question 2: Pressure reduction is achieved by using multiple pressure relief lines to discharge the high-pressure, powder-containing gas into the coal powder filter, thereby bringing the lockhopper to normal pressure. Question 3: The material used for the coal lockhopper does not need to be heat-resistant; the temperature in that area is not very high, around 80 degrees Celsius
I would like to know how stable feeding is achieved when feeding coal powder. Thank you
The second floor explained it in great detail. Learned* it