The problem of clogged slag ports
Thread Content
Plant No. 1 has a Texaco gasification unit with a capacity of 3.2 meters/6.4 MPa; it has been in operation for over three years. Due to blockages in certain areas, it has not been possible to reach its full operating capacity. The ash content in the coal is quite low, around 10%, and its ash melting point is also low, at about 1,200 degrees Celsius. The plant has tried various solutions and consulted many experts, but the problem still remains unsolved. Please do not rush to give answers; think carefully about all possible scenarios before discussing them with everyone. There is also a Texaco gasification unit with parameters of 2.8 meters/4.2 Mpa, which has been in operation for over 5 years without any problems. Recently, it stopped operating suddenly due to blockage at the slag outlet, which caused high temperatures in the unit’s arms; the coal quality was also analyzed. I would like everyone to discuss this matter together. Thank you all for your participation
The typos upstairs are really serious.
The OP’s question is quite interesting. In actual chemical production, such situations often arise: things that should be fine both theoretically and based on experience still go wrong, which is baffling. This is why experience and seniority are valued more in chemical production than academic qualifications. I’ll cut to the point: could the original poster provide details such as the composition of the process gas for a furnace with specifications of 3.2 m/6.4 MPa, the designed and actual processing capacities, the carbon content in the coarse slag, the shape of the coarse slag, the oxygen-to-coal ratio, the temperature of the process gas, and the pressure difference at the slag outlet? This will enable a more targeted analysis. Since so many experts have failed to solve it, the original poster should provide more detailed information on certain parameters; as the saying goes, \"the devil is in the details.\"
Make some parameters public so that everyone can take a look and see what the problem might be.
The technician upstairs should tell us the important process parameters accurately. As the saying goes, there are always more solutions than problems; please trust that we will surely resolve the issues that have been bothering you for so long. Let’s make progress together. Thank you!
A low ash fusion point of coal does not necessarily mean that it will cause blockages in the slag outlet; what matters is the viscosity of the coal ash. If the viscosity range of the coal ash is narrow, such coal is not suitable for use in fluidized bed gasification. It is recommended to choose coal types with a wide range of ash viscosity.
Hehe! Another problem with the slag outlet being blocked! It’s a bit awkward for you, right, dealing with the problems that the gasification furnace operation expert you hired often encounters and is unable to solve? A professor engaged in research might spout nonsense to you, leaving you confused, but that still won’t solve the problem. Why not try a different approach and give my method a chance? It’s fundamentally different from theirs!
Thank you to the expert above for the reminder. In future operations, when selecting coal, in addition to considering its ash fusion point, we should also take into account the range of ash viscosity
Reply to hjy2000: The current method of operation uses temperature as the control variable, but temperature is not an independent variable that can be changed freely; it does not meet the basic requirements for a control variable. This is why the problem of slag port blockage cannot be resolved. My approach uses oxygen level and slurry volume as control variables, which can fundamentally solve the problem of slag hole blockage.
The last edit to this post was made by chinglq on 2010-9-10 at 11:36, in response to hjy2000: That means you haven’t yet found the appropriate operating conditions – conditions that allow the overall temperature distribution within the gasification furnace to be above FT, while still achieving the desired gasification results. The operation process sometimes results in a lower temperature at the slag outlet, which leads to blockage.