Method for producing organic acids and organic acid degradation compounds from biomass

A process for producing levulinic acid, comprising:

• contacting a lignocellulosic biomass comprising a six carbon chain sugar precursor with steam to heat the lignocellulosic biomass to a temperature of about 170° C. to about 230° C. within a tubular reactor with axial mixing to produce an at least partially hydrolyzed lignocellulosic biomass comprising a six carbon chain sugar;
• contacting the at least partially hydrolyzed lignocellulosic biomass with a first mineral acid and heating the at least partially hydrolyzed lignocellulosic biomass to a temperature of about 150° C. to about 250° C. within a plug flow reactor to convert the six carbon chain sugar to a first product comprising levulinic acid and tar;
• heating a sludge from a pulp and paper mill comprising an additional six carbon chain sugar to convert the additional six carbon chain sugar to a second product comprising levulinic acid and tar;
• mixing the first product and the second product to produce a combined product;
• and
• separating the levulinic acid from the tar to produce a purified levulinic acid product.

A process for producing one or more organic acids, comprising:

• introducing a heated mixture comprising steam and a lignocellulosic biomass comprising a six carbon chain sugar precursor to a first reactor, wherein the first reactor comprises a tubular reactor with axial mixing;
• at least partially hydrolyzing the lignocellulosic biomass within the first reactor to produce an at least partially hydrolyzed lignocellulosic biomass comprising a six carbon chain sugar;
• introducing the at least partially hydrolyzed lignocellulosic biomass to a second reactor, wherein the second reactor comprises a plug flow reactor;
• heating the at least partially hydrolyzed lignocellulosic biomass within the second reactor to a temperature of about 150° C. to about 250° C. to produce a first product comprising a first organic acid;
• introducing a sludge from a pulp and paper mill comprising an additional six carbon chain sugar to a third reactor;
• and
• heating the sludge within the third reactor to a temperature of about 150° C. to about 250° C. to produce a second product comprising a second organic acid.