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干式机械真空泵(MVP)在钢水脱气工艺中的应用在过去10年间取得了巨大进展,但主要局限在炉容小于150t;推广到更大炉容的工作正在进行中。因为有蒸汽来源,蒸汽喷射真空泵(SVP)主要用于联合钢厂150~350t的大炉容。除了投资和运行成本方面的考虑,所有真空工艺和设备类型都能够不受限制地使用任何类型的现代真空泵系统。这2种系统都能够满足全部的冶金要求。由于MVP系统的运行成本明显降低,所以有必要重新审视在减少漏气、使用保护气体和降低泵组与冶金反应罐间压力损失等方面的努力。这2种系统的能效都得到了提高,但MVP的能源优势更为明显。在对真空泵系统进行比较时,应当只考虑总成本,包括为满足排放限制和安全标准的要求而必须付出的成本以及反应罐内的压力。此外,还应当重新考虑除尘系统的类型和使用,因为它们能够通过减少清理次数、节省用水、减少淤泥处理、降低SVP系统的设计抽气能力来显著降低成本。在同基于体积流量的MVP比较前,需要利用一个特殊的系数对SVP的质量流进行修正。根据所选泵需要的工作压力,MVP系统能够以明显低于SVP系统的质量流在反应罐达到同样的性能。
The application of dry mechanical vacuum pumps (MVPs) to the degassing of molten steel has made tremendous progress over the past decade, but the main limitation is that the furnace capacity is less than 150t. Work is underway to extend the furnace capacity to larger furnaces. Due to the steam source, the steam jet vacuum pump (SVP) is mainly used for large furnace capacity of 150 ~ 350t in steel mills. In addition to investment and operating costs considerations, all types of vacuum processes and equipment types can use any type of modern vacuum pump system. Both systems meet all metallurgical requirements. Due to the significantly lower operating costs of MVP systems, there is a need to revisit efforts to reduce blow-bys, use shielding gas and reduce pressure losses between pump and metallurgical reactors. The energy efficiency of both systems has been improved, but MVP’s energy advantage is even more pronounced. When comparing vacuum pump systems, only the total cost, including the costs that must be met to meet emission limits and safety standards, and the pressure inside the reaction tank, should be considered. In addition, the type and use of the dedusting system should also be reconsidered as they can significantly reduce costs by reducing the number of cleanups, saving water, reducing silt disposal, and reducing the design pumping capacity of SVP systems. Before comparing with volume-based MVP, a special coefficient needs to be used to correct SVP mass flow. Depending on the operating pressure required for the selected pump, the MVP system achieves the same performance in the reaction tank with mass flow significantly lower than that of the SVP system.