Liquor-to-liquor differences in combustion and gasification processes: Nitrogen oxide formation tendency

Seventeen black liquors are characterized for their combustion properties b y studying the behavior of single liquor droplets or small liquor samples i n laboratory furnaces under well controlled conditions. This paper discusse s the NO formation tendency of the liquors that originated from North Ameri ca, Scandinavia, and the Far East. Fourteen wee kraft liquors, two were sod a liquors, and one was a sulfite liquor. Most liquors used had nitrogen con tents of 0.06%-0.20% dry solids. One liquor had 0.75% nitrogen. The authors measured the split between volatile nitrogen and char nitrogen, the tenden cy of the liquors to form NO during char combustion, and the total NO forma tion tendency of the liquors. The results showed differences among the liqu ors in their tendency to form NO in char combustion and black liquor drople t combustion. Total NO formation tendency test results showed good agreemen t with measured recovery boiler NO emission field data.