Method for co-producing ethanol, cellulose and compound fertilizer by using crop straw as raw material

Abstract

The invention discloses a method for co-producing ethanol, cellulose and compound fertilizer by using crop straws as a raw material, which comprises: adding coarsely ground crop straws and acidic aqueous solution of which the pH value is 2 to 4 in mass part ratio of 1:2-3 into a cooking kettle and heating the mixture to 60 to 90 DEG C to cook the mixture for 4 to 8 hours; squeezing reactants to obtain solution, neutralizing the solution, regulating the concentration of the solution to 15 to 25 percent, producing ethanol by the conventional fermentation process, washing the straw residues obtained after squeezing by clean water, using the liquid obtained after the washing in the feeding of next batch of raw material, washing and squeezing the resulting material again, and mixing the obtained straw residue with aqueous solution containing a lignin leaching agent in a mass part ratio of 1:6-8, heating the mixture to 60 to 90 DEG C for cooking the mixture for 4 to 8 hours, filtering the mixture to obtain a coarse product of cellulose, washing and bleaching the coarse product of cellulose, filtering the coarse product of cellulose under compression for dewatering and drying the coarse product of cellulose to obtain a finished product of cellulose, wherein the bleaching liquid is used in the reaction of the next batch of raw material; and concentrating residual liquid obtained after the extraction of ethanol and the filtration of the coarse product of cellulose, drying the concentrate by spray for granulation, and making the compound fertilizer. As the method can extract ethanol and coproduce the cellulose and the compound fertilizer, so the drawbacks of single product production, waster source waste and heavy environmental pollution in the prior art are avoided.

Description

Technical field: [0001] The invention relates to a method for co-producing ethanol, cellulose and compound fertilizer by using crop stalks as raw materials. The crop stalks refer to grass plant stalks such as corn, sorghum and wheat grass. Background technique: [0002] The existing processing and utilization technologies of corn, sorghum and other straws are various: straw crushing and returning to the field; straw making cellulose (pulp); straw making organic fertilizer, activated carbon or feed; straw power generation; straw gasification; bioenergy, etc. These technologies extract and utilize part of the raw material components, and do not reflect the maximum value of raw materials. Common problems are low raw material utilization rate, single product, little value-added processing, serious "three wastes" in the processing process, poor direct and social benefits of enterprises, poor direct and social benefits of farmers, and Small income and other issues. Therefore, the...

AI Technical Summary

Problems solved by technology

The traditional process often adopts chemical method, using the mixture of sodium hydroxide and sodium sulfide as the cooking agent. The waste liquid after cooking is directly discharged without rational use, and contains a large amount of chlorine, sulfur, sodium, etc., causing serious environmental pollution. The cost of pollution control is very high