Process for producing methyl ester by using waste grease

Abstract

The invention discloses a process for producing methyl ester by using waste grease. The process comprises the following working steps of: (1) collecting a kitchen waste grease raw material, recovering glycerol and putting the kitchen waste grease raw material and the glycerol into an esterification reactor; (2) preheating to control temperature and vacuum; (3) carrying out a reverse esterification reaction on glycerol and free fatty acid; (4) reducing the acid value of the material to 2mgKOH/g; (5) adding methanol and a catalyst according to a certain proportion, mixing the methanol and the catalyst in a mixing tank, and then putting the mixture into a transesterification reaction reactor; (6) after the reaction, discharging reaction products glycerol and soapstock at a settling position at the bottom of the reactor to a glycerol treatment section; (7) putting the obtained crude methyl ester into a heat exchanger for heat exchange and heating; and (8) heating, putting the methyl ester into a distillation tower, evaporating and separating the methyl ester in the distillation tower, removing heavy impurities (namely plant pitch) at the tower bottom, condensing and refluxing the mixed methyl ester through a tower top condenser, and then collecting the mixed methyl ester in an intermediate tank. Kitchen waste grease which cannot be directly used is utilized and matched with recycled glycerol to extract methyl ester, and resources are effectively utilized.

Description

technical field [0001] The invention relates to the technical field of methyl ester production, in particular to a process for producing methyl ester by using waste oil. Background technique [0002] Methyl ester, also known as fatty acid methyl ester, is a widely used raw material for biodiesel. Two types of surfactants can be produced from fatty acid methyl ester; one is the production of fatty acid methyl ester sulfonate (MES) through sulfonation neutralization, The other is to produce fatty alcohol through hydrogenation; its price is relatively expensive; if it is purchased directly, it will consume a lot of cost, which is not convenient for the long-term development of the enterprise; at present, the main production of methyl ester is the acid-base two-step method, In the production process, acid catalysis must be carried out for those with high acid value, resulting in a large amount of waste acid and relatively large pollution, which cannot meet the current concept of...

AI Technical Summary

Problems solved by technology

[0002] Methyl ester, also known as fatty acid methyl ester, is a widely used raw material for biodiesel. Two types of surfactants can be produced from fatty acid methyl ester; one is the production of fatty acid methyl ester sulfonate (MES) through sulfonation neutralization, The other is to produce fatty alcohol through hydrogenation; its price is relatively expensive; if it is purchased directly, it will