| 摘要 |
<p>Hereby a novel process is described which is capable to take most any subdidvided, chipped, shredded, hammermilled lignocellulosic forest and/or agricultural residue, pure or in mixtures thereof, and with the aid of a chemical agent,which is essentially a mixture of an organic volatile solvent with water, such as ethanol or acetone, acidified with either an inorganic strong acid such as hydrochloric, sulphuric or phosphoric acid, or an organic acid such as oxalic, formic, citric, maleic, plicatic, tannic, tartaric, trichloroacetic or trifluoroacetic acid, convert it into pulp, crystalline cellulose, dissolved chemicals such as sugars, lignins, furfurals and organic acids in high yield. The process of conversion is continuous but can be subdivided-into stages according to the order of product formation. The conditions under which these products are formed are very conducive to rapid hydrolysis and usually involve liquor pH at 4 and lower, a temperature of 160.degree.C but not exceeding 210.degree.C, and a pressure appropriate with these temperatures and the cooking liquor composition. Product composition is mainly influenced by cooking time at maximum specified temperature and liquor composition,i.e., more than one product mix can be produced with a single set of temperature/pressure and cooking liquor composition by merely increasing or decreasing the exposure time at maximum temperature. The equipment is so designed that it make possible the production and recovery of the whole range of chemicals (products) indicated above. It is a further characteristic of the process that it treats most all lignocellulosics with nearly equal efficiency and thus such plant materials may also be processed in mixture without serious deterioration of product quality and process efficiency. A high degree of cooking chemical recovery is possible and continuous recovery is an integral and important part of the process. Thus this invention does not limit itself to the solvent system by which such rapid production of high to low-yield pulps, bulk lignins and sugars and sugar dehydration products are possible from all types of lignocellulosics, neither is it limited to the conditions under which such flexibility is possible but is also concerned with the apparatus which would allow efficient, economic, orderly and controlled high yield manufacture of such a product mix as outlined in Figure 1.</p> |
