对于天然气的水蒸气重整,从进料(天然气)中脱硫;而对于煤的气化,含硫化合物从粗合成气中脱除,而不是进料(煤),为什么?( 10 分) For the process of steam reforming of natural gas, sulfur compounds are removed from feedstocks (natural gas), while for coal gasification, they are removed from raw syngas rather than feedstocks (coal), why? (10 points)