Pollutant-free process for producing a clean burning fuel gas from organic-containing waste materials

Claim 2

A method in accordance with claim 1 wherein said organic-containing material is kraft black liquor and said malodorous emission streams are gases produced in a kraft mill pulping process.

Claim 3

The method of claim 2 wherein said pyrolysis is initiated in a first enclosed pyrolysis zone to which external heat is applied and said stable fuel is formed in a second enclosed pyrolysis zone in communication with said first zone.

Claim 4

The method of claim 4 wherein said side stream providing oxygen is introduced into said second zone in an amount sufficient to maintain said cracking temperature and render said pyrolysis self-sustaining but less than that required for complete stoichiometric combustion of said material, and a portion of said gaseous end product is burned to provide such external heat applied to said first zone.

Claim 5

A method in accordance with claim 5 wherein the amount of said oxygen is up to about 15 percent of that amount required for complete stoichiometric combustion.

Claim 6

In the processing of kraft black liquor produced in a kraft wood pulping process wherein malodorous emissions of sulfur-containing gaseous side streams are formed as by-products, and wherein destructive distillation and pyrolysis of said black liquor is effected in an enclosed zone at an elevated cracking temperature for a time sufficient to form as the gaseous end product a stable clean burning fuel containing hydrogen sulfide, oxygen is introduced into said zone in an amount insufficient to accomplish complete oxidation, and wherein recombination reactions of intermediate products are prevented by maintaining said cracking temperature during said destructive distillation and pyrolysis to minimize formation of atmospheric pollutants; the improvement of destroying the malodorous portion of such a by-product sulfur-containing side stream and simultaneously utilizing such side stream as a source for providing said oxygen which comprises the step of introducing such by-product side stream into said zone to pyrolyze said malodorous portion as well as said black liquor.