초록 ▼

A multi-function process is described for the separation of cellulose fibers from the other constituents of lignocellulosic biomass such as found in trees, grasses, agricultural waste, and waste paper with application in the preparation of feedstocks for use in the manufacture of paper, plastics, et

A multi-function process is described for the separation of cellulose fibers from the other constituents of lignocellulosic biomass such as found in trees, grasses, agricultural waste, and waste paper with application in the preparation of feedstocks for use in the manufacture of paper, plastics, ethanol, and other chemicals. This process minimizes waste disposal problems since it uses only steam, water, and oxygen at elevated temperature in the range of 180.degree. C. to 240.degree. C. for 1 to 10 minutes plus a small amount of chemical reagents to maintain pH in the range 8 to 13. An energy recuperation function is important to the economic viability of the process.

대표청구항 ▼

1. A method of treating lignocellulosic biomass to produce purified cellulose containing less than 20% lignin, said method comprising the steps of:providing a lignocellulosic feedstock having an average constituent thickness of at most 1′; introducing said feedstock into a pressure vessel having at

1. A method of treating lignocellulosic biomass to produce purified cellulose containing less than 20% lignin, said method comprising the steps of:providing a lignocellulosic feedstock having an average constituent thickness of at most 1′; introducing said feedstock into a pressure vessel having at least two reaction zones; maintaining said feedstock in the pressure vessel for a residence time; heating said feedstock in a first reaction zone to a temperature of from about 180.degree. C. to about 240.degree. C. to dissolve hemicellulose; removing said dissolved hemicellulose from the heated feedstock transferring said heated feedstock from said first reaction zone to a second reaction zone; subjecting said transferring feedstock to a counterflow of hot wash water of pH of from about 8 pH to about 13 pH to create residual solids containing cellulose and a wash water containing dissolved materials; and separating the residual solids containing purified cellulose from the filtered wash water, wherein said separated cellulose contains less than 20% lignin.