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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150 T炉容以下；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150～350 T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。这两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。这两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系统能够以大大低于SVP系统的质量流在反应罐达到同样的性能。“,”The-use-of-dry-operating-mechanical-vacuum-pumps-(mvp)for-steel-degassing-has-made-a-tremendous-step-forward-in-the-past-10-years-but-is-still-confined-to-melts-below-150-t-while-its-progress-towards-larger-melt-sizes-is-not-finished.steam-ejector-vacuum-pumps-(svp)are-mainly-used-on-larger-melt-sizes-from-150-to-350t-in-integrated-steel-plants-because-of-the-availability-of-steam.Beside-the-consideration-of-investment-and-operating-costs-there-is-no-restriction-in-using-any-type-of-modern-vacuum-pump-systems-for-all-vacuum-processes-and-plant-designs.Both-systems-fulfil-all-metallurgical-requirements.Considering-the-important-savings-in-operating-cost-offered-by-mvp-systems-it-is-worth-reconsidering-the-efforts-for-reducing-air-leaks,the-use-of-protective-gases-and-pressure-losses-between-the-pump-set-and-the-metallurgical-reaction-vessel.Both-systems-have-made-progress-in-energy-optimising-but-the-mvps-have-a-striking-energy-advantage.Only-the-overall-costs-should-be-considered,including-those-necessa-ry-to-meet-emission-constraints-and-safety-standards-and-only-the-pressure-prevailing-at-the-reaction-vessel-is-to-be-considered-when-comparing-vacuum-pump-systems.Also-the-means-and-use-of-dust-abatement-systems-should-be-re-considered-since-they-offer-cost-savings-by-reducing-the-frequency-of-cleaning,less-wear,little-sludge-handling-and-a-significantly-lower-design-suction-capacity-of-svp-systems.The-svp-mass-flow-need-is-to-be-corrected-by-a-special-co-efficient-before-being-applied-to-the-volume-conveying-mvp.Depending-on-the-operational-pressure-required-for-the-pump-design,mvp-systems-can-reach-the-same-performance-at-the-reaction-vessel-with-much-less-mass-flow-capacity-than-needed-by-a-svp-system.