Group Inc. United States

The Lambda Group Inc. was an industrial organization involved in coal business, which supported the development of a coal cleaning process led by Jo Davison, during the second half of the 1980s. 

The developed process aimed for the removal of iron and sulfur from coal. While several patents for microbial removal of pyrite from coal exist, this one is unique because of the microbial mixture developed by the group for this purpose, which is partially 

In an open report, this company informed how the process evolved into three different applications, depending on where the coal was cleaned and what part of the coal was being cleaned. Only the latter is fully based in the awarded patent. The process was presented internationally as the Lambda Coal Cleaning Process [142] in 1987, but after that announcement there is no additional information on whether it reached commercial demonstration. 

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