The effects of moderate coal cleaning on the microbial removal of organic sulfur. Technical report, September 1--November 30, 1991

Abstract

The purpose of this project is to investigate the possibilities of developing an integrated physical/chemical/microbial process for the precombustion removal of sulfur from coal. An effective pre- combustion coal desulfurization process should ideally be capable of removing both organic and inorganic sulfur. A variety of techniques exist for the removal of inorganic sulfur from coal, but there is currently no cost-effective method for the pre-combustion removal of organic sulfur. Recent developments have demonstrated that microorganisms are capable of specifically cleaving carbon-sulfur bonds and removing substantial amounts of organic sulfur from coal. However, lengthy treatment times are required. Moreover, the removal of organic sulfur form coal by microorganisms is hampered by the fact that, as a solid substrate, it is difficult to bring microorganisms in contact with the entirety of a coal sample. This study will examine the suitability of physically/chemically treated coal sample for subsequent biodesulfurization. Physical/chemical processes primarily designed for the removal of pyritic sulfur may also cause substantial increases in the porosity and surface area of the coal which may facilitate the subsequent removal of organic sulfur by microoganisms. During the current quarter, coal samples that have been chemically pretreated with methanol, ammonia, and isopropanol were examined formore » the removal of organic sulfur by the microbial culture IGTS8, an assay for the presence of protein in coal samples was developed, and a laboratory-scale device for the explosive comminution of coal was designed and constructed.« less