Feedstock oil→standing watershed→centrifugal watershed→heating heating → flash dehydration→temporary storage tank
Raw material is pumped into the temporary storage tank group,the first precipitation watershed,and then into the centrifuge watershed,finally flash dehydration under vacuum conditions.Pretreatment oil is stored in a temporary storage tank.
2 esterification workshop
Feedstock oil→esterification (catalyst methanol) →sedimentation separation (acid water neutralization)→water elution water (methanol water)→transesterification (catalyst methanol)→sedimentation separation (acid water neutralization)→esterification→water elution water (methanol water) →methyl ester distillation workshop
Methanol distillation → methanol
A. Esterification
The free fatty acids in the feedstock have a very adverse effect on the transesterification reaction, esterification purpose is to remove the free fatty acids.The principle of esterification is that in the presence of an acidic catalyst, the free fatty acid in the raw material and excess methanol pre-methyl esterification reaction, the free acid into methyl ester.
Esterification reaction formula：
General esterification reaction conditions for the temperature of 68~72℃, the time is determined by the raw material index.After esterification, the acid value drops to 3 or less.
Sedimentation separation of acid water and methyl ester, methyl ester water after eluting water into the transesterification.
B. Transesterification
Transesterification reaction is the reaction of oil with an alcohol to produce methyl ester and glycerol.
Transesterification reaction formula：
C. Methanol water neutralization
From the esterification kettle washed down the water was acidic, after the oil tank points to a small amount of oil, acid-base neutralization in the neutralization tank, sodium sulfate and water are generated.
D. Methanol distillation
Acid-base and washed with water in addition to water and sodium sulfate also contains a large amount of methanol and a small amount of glycerol, depending on the boiling point of methanol and water, glycerol, methanol was recovered with a distillation column and set aside.
3 methyl ester distillation workshop
Crude fatty acid methyl ester first base refining, further reducing the acid value,and then into the methyl ester distillation system,after distillation to obtain the finished methyl ester.
