Solar Coal-Gasification Reactor for Hydrocarbon-Free Synthesis Gas

摘要

In many applications, the hydrocarbon content of the synthesis gas produced in coal gasification is very valuable. In SNG production, the end product is a high Btu gas composed of methane and higher hydrocarbons. Furthermore, the liquid hydrocarbons can be even more valuable as feedstocks for other processes. In other applications such as methanol production, the hydrocarbon content of the synthesis gas is a non-reactive diluent that must be bled away from the product synthesis area to keep its concentration from buildng up. The liquid hydrocarbons that are a valuable product in a large-scale plant can cost more to remove from the synthesis gas than they are worth in a small-scale plant. In addition to the above benefits, this reactor requires substantially less steam in the coal gasification process. The reactor is able to produce hydrocarbon-free synthesis gas because it withdraws the pyrolysis gases from the reactor as they are formed and reinjects them above the char gasification zone where they are steam reformed into CO, CO sub 2 , and H sub 2 . Since almost all of the hydrocarbons released in coal gasification come off with the pyrolysis gases, the reactor will produce nearly hydrocarbon-free gas. (ERA citation 06:028064)