CN101289628A - Process for producing biodiesel from mixed fatty acid - Google Patents

Abstract

The invention relates to a method for manufacturing biodiesel oil by mixed fatty acid. The method is as follows: firstly, animal and plant oil waste materials, soapstock, acidified oil and edible recovery oil are mixed to remove mechanical impurities, and refined oleic acid and mixed fatty acid are fractionated through pretreatment; then, the mixed fatty acid is added in an esterifying agent to carry out esterification through three sets of vibration tube-type continuous esterificators; crude methanol is reclaimed and then is pumped into a methanol scrubbing tower to be washed by methanol; and ester phase matter is fed in a methanol recovery tower to distill residual methanol, and then is fed in a flash fractionating tower to fractionate a biodiesel oil finished product. Pretreatment hydrolysis is adopted to fractionate 40 to 60 percent of refined oleic acid which is about 10,000 yuan/ton according to market price and has higher market value; the method can increase the economic benefits of a biodiesel oil enterprise and reduces the composite cost of biodiesel oil production; a vibration tube-type continuous esterification process has short esterification time (only 1.5 hours) and can save a great deal of energy sources; moreover, the yield of fatty acid methyl ester is high and can reach to above 98 percent, and product quality can meet the requirements of the national BD100 standard.

Description

A kind of with mixed fatty acid production method of bio-diesel oil

One, technical field

The present invention relates to a kind of production method of biofuel, specifically with mixed fatty acid production method of bio-diesel oil.

Two, background technology

Along with the mineral oil storage capacity reduces year by year, because biofuel is the most approaching at aspect such as combustionproperty, characteristic and mineral diesel, also have renewable, burning fully, little, the readily biodegradable of tail gas pollution, characteristics such as harmless, various countries are raw material with the vegetables oil in Development and Production all, do catalyzer, ester-interchange method production biofuel with alkali.At present using vegetable oil production biofuel, the prices of raw and semifnished materials is that the twice of mineral diesel is many, therefore can't produce.Domestic existing each manufacturing enterprise is a raw material with animal and vegetable oil leftover, soap stock, acidifying oil and edible refiltered oil, and catalyzer, esterification process production biofuel are done in acid, also run into same problem.Animal, plant oil leftover acidifying oil and edible refiltered oil price are many about 5000 yuan/ton at present, (about 6200 yuan/ton of mineral diesel market price), adopt existing Technology to carry out the production esterification, need with more than 6 hours, production rate is slow, and free glycerol content and total glycerol content, acid number all exceed the BD100 standard.Production technique such as number of patent application CN 1031070C employing acid with two-step approach are that catalyzer carries out pre-esterification, and after reaction was finished, with an acidic catalyst and residual free fatty acids, residue alkali was as transesterification reaction in adding pure and mild excess base.Adopt above-mentioned two-step approach reaction acid number can reach standard, free glycerol and glycerine total content still do not reach national standard, neutralize with alkali in addition, can make a part of fat saponification in the raw material, productive rate is low, and catalyst levels can increase, double process period, and facility investment is big, and energy consumption significantly rises, in addition, need basic catalyst is removed from product, have to contain alkali waste water generation, contaminate environment in a large number, recovery glycerine difficulty, the production cost height.As the production method of the disclosed biofuel of Chinese patent application CN 1473907A, esterification 6 hours, esterification yield 93%, acid number 4.5mgKOH/g, 10% steams excess carbon residue 0.5, and total glycerol content is not up to standard yet, and this technology is because production cost height and acid number is not up to standard can't put into production.

Three, summary of the invention

The technical problem to be solved in the present invention is: a kind of new method with mixed fatty acid production biofuel is provided, to solve the problem that prior art exists, reduce production costs, save water resources, reduce environmental pollution, make every index of biofuel meet national BD100 standard.

The technical scheme that solution the technology of the present invention problem is taked is: at first vegetable and animals oils waste material, soap stock, acidifying oil, edible refiltered oil or its mixture material are removed mechanical impurity, adjust pH value to 3～4, with the steam stirring of directly heating, water content 40～50% times, send into hydrolysis tower hydrolysis more than 6 hours under 220 ℃ of pressure 20MPa of temperature, the sample examination acid number is lowered the temperature when 180mgKOH/g is above and is put into slurry tank, emit lower floor's G ﹠ W, upper layer material is dewatered, and the dehydration aftercut goes out essential oil acid and mixed fatty acid; Mixed fatty acid is added esterifying agent, through three groups of vibration tube-type continuous esterification devices, under 100～170 ℃, every group of liquid hourly space velocity of pressure 4～10MPa 0.5 hour, esterification 1.5 hours, reclaim thick methyl alcohol, pump into methanol wash tower 97% methanol wash then, ester phase thing is entered methanol distillation column steam the residual methyl alcohol that heats up in a steamer, advance the fractionation of flash distillation separation column again and get the biofuel finished product.Vibration tube-type continuous esterification device is made up of mixing tank, injection pump, vibrator, tubular type esterification device, Methanol Recovery water trap, and three groups of vibration tube-type continuous esterification device polyphones are installed.Vibration tube-type continuous esterification device is inventor's patent of application in addition, this ominous stating.

Because of the esterifying agent of prior art easily makes the raw material carbonization, yield is reduced, esterifying agent of the present invention is made up of 1.8% sulfuric acid, 0.2% sulfonic acid, 98% methyl alcohol.

The detailed process of esterification is, mixed fatty acid and esterifying agent are input in first group of mixing tank, the volume ratio of the two 100: 15, enter first group of tubular type esterification device after the mixing, 100～170 ℃ of esterification temperatures, pressure 4～10MPa, liquid hourly space velocity 0.5 hour, reacted and entered the Methanol Recovery water trap, reclaimed thick methyl alcohol and deviate from the water that esterification produces; Enter second group of mixing tank again and add esterifying agent, the volume ratio of the two is 100: 10, enters second group of tubular type esterification device after the mixing, 100～170 ℃ of esterification temperatures, pressure 4～10MPa, liquid hourly space velocity 0.5 hour, reacted and entered the Methanol Recovery water trap, reclaimed thick methyl alcohol and deviate from the water that esterification produces; Enter the 3rd group of mixing tank again and add esterifying agent, the volume ratio of the two is 100: 10, enters the 3rd group of tubular type esterification device after the mixing, 100～170 ℃ of esterification temperatures, pressure 4～10MPa, liquid hourly space velocity 0.5 hour has been reacted and has been entered the Methanol Recovery water trap, reclaims thick methyl alcohol, pump into methanol wash tower 97% methanol wash then, contain sour methyl alcohol phase furnishing esterifying agent again, ester phase thing is entered methanol distillation column steam the residual methyl alcohol that heats up in a steamer, advance the fractionation of flash distillation separation column again and get the biofuel finished product.

Positively effect of the present invention is: adopt first pre-treatment hydrolysis to fractionate out the essential oil acid of 40-60%, deglycerizin, about 10000 yuan/ton of essential oil acid market prices have higher marketable value, can improve the biofuel economic benefit of enterprises, reduce the comprehensive cost of production of biodiesel; Vibration tube-type continuous esterification technique esterification time is short, only needs 1.5 hours, can save a large amount of energy; Fatty acid methyl ester yield height can reach more than 98%, washing is made into methanol wash save great lot of water resources, has deducted because of the pollution of discharge water wash water to environment, and quality product can reach national BD100 standard-required.

Four, embodiment

Embodiment 1:

The vegetable and animals oils waste material of mechanical impurity will be removed, soap stock, acidifying oil, the edible wet goods that reclaims, mix and be put in the oil groove of heating, add esterification technique and get off to contain aqueous acid, pH value is transferred to 3～4, with the steam stirring of directly heating, the water yield 40～50% times, send into hydrolysis tower hydrolysis more than 6 hours under 220 ℃ of pressure 20MPa of temperature, the sample examination acid number is lowered the temperature more than 180mgKOH/g and is put into slurry tank, emit lower floor's G ﹠ W, extract raw glycerine with boiler and production waste heat, upper layer material is delivered to the decompression evaporator dehydration, taken off water and delivered to the flash distillation separation column and fractionate out and be worth higher essential oil acid supply the market (about 10000 yuan/ton of market prices), it is lower to fractionate out value, the mixed fatty acid production biofuel of acid number 209mgKOH/g, residue plant heavy oil is for market.

To add esterifying agent through the acid of the animals and plants mixing oil of aforementioned pretreated acid number 209mgKOH/g fat, volume ratio was 100: 15, with liquid hourly space velocity 0.5 hour, be fed in one group of vibration tube-type esterification of mat woven of fine bamboo strips device, 130 ℃ of esterification temperatures, pressure 5MPa collects thick methyl alcohol and deviates from water; First group of dehydration raw material added esterifying agent, and volume ratio is 100: 10, with liquid hourly space velocity 0.5 hour, be fed in second group of vibration tube-type esterification device, and 130 ℃ of esterification temperatures, pressure 5MPa collects thick methyl alcohol and deviates from water; Second group of dehydration raw material added esterifying agent, volume ratio is 100: 10, with liquid hourly space velocity 0.5 hour, be fed in the 3rd group of vibration tube-type esterification device 130 ℃ of esterification temperatures, pressure 5MPa, collect thick methyl alcohol, sample examination acid number 0.53mgKOH/g pumps into methanol wash tower 97% methanol wash then, ester phase thing is entered methanol distillation column steam the residual methyl alcohol that heats up in a steamer, advance the fractionation of flash distillation separation column again and get the biofuel finished product.

Embodiment 2:

Will through aforementioned pretreatment process handle the palm oil fatty acid of acid number 193mgKOH/g add esterifying agent, volume ratio is 100: 15, is fed in first group of vibration tube-type esterification device 150 ℃ of esterification temperatures in 0.5 hour with liquid hourly space velocity, pressure 6MPa collects thick methyl alcohol and deviates from water; First group of dehydration raw material added esterifying agent, and volume ratio is 100: 10, with liquid hourly space velocity 0.5 hour, be fed in second group of vibration tube-type esterification device, and 130 ℃ of esterification temperatures, pressure 5MPa collects thick methyl alcohol and deviates from water; Second group of dehydration raw material added esterifying agent, volume ratio is 100: 10, with liquid hourly space velocity 0.5 hour, be fed in the 3rd group of vibration tube-type esterification device 130 ℃ of esterification temperatures, pressure 5MPa, collect thick methyl alcohol, sample examination acid number 0.37mgKOH/g pumps into methanol wash tower 97% methanol wash then, ester phase thing is entered methanol distillation column steam the residual methyl alcohol that heats up in a steamer, advance the fractionation of flash distillation separation column again and get the biofuel finished product.

Claims (4)

1, a kind of with mixed fatty acid production biofuel method, it is characterized in that: at first with the vegetable and animals oils waste material, soap stock, acidifying oil, edible refiltered oil or its mixture material are removed mechanical impurity, adjust pH value to 3～4, with the steam stirring of directly heating, water content 40～50% times, send into hydrolysis tower, hydrolysis is more than 6 hours under 220 ℃ of pressure 20MPa of temperature, the sample examination acid number is lowered the temperature when 180mgKOH/g is above and is put into slurry tank, emit lower floor's G ﹠ W, upper layer material is dewatered, and the dehydration back is taken in underpressure distillation and is fractionated out essential oil acid and mixed fatty acid; Mixed fatty acid is added esterifying agent, through three groups of vibration tube-type continuous esterification devices, under 100～170 ℃, every group of liquid hourly space velocity of pressure 4～10MPa 0.5 hour, esterification 1.5 hours, reclaim thick methyl alcohol, pump into methanol wash tower methanol wash then, contain sour methyl alcohol phase furnishing esterifying agent again, ester phase thing is entered methanol distillation column steam the residual methyl alcohol that heats up in a steamer, advance the fractionation of flash distillation separation column again and get the biofuel finished product.

2, according to claim 1 with mixed fatty acid production biofuel method, it is characterized in that: vibration tube-type continuous esterification device is made up of mixing tank, injection pump, vibrator, tubular type esterification device, Methanol Recovery water trap, and three groups of vibration tube-type continuous esterification device polyphones are installed; Mixed fatty acid is added esterifying agent to be input in first group of mixing tank, the volume ratio of the two 100: 15, enter first group of tubular type esterification device after the mixing, 100～170 ℃ of esterification temperatures, pressure 4～10MPa, liquid hourly space velocity 0.5 hour has been reacted and has been entered the Methanol Recovery water trap, reclaims thick methyl alcohol and deviates from the water that esterification produces; Enter second group of mixing tank again and add esterifying agent, the volume ratio of the two is 100: 10, enters second group of tubular type esterification device after the mixing, 100～170 ℃ of esterification temperatures, pressure 4～10MPa, liquid hourly space velocity 0.5 hour, reacted and entered the Methanol Recovery water trap, reclaimed thick methyl alcohol and deviate from the water that esterification produces; Enter the 3rd group of mixing tank again and add esterifying agent, the volume ratio of the two is 100: 10, enter the 3rd group of tubular type esterification device after the mixing, 100～170 ℃ of esterification temperatures, pressure 4～10MPa, liquid hourly space velocity 0.5 hour, reacted and entered the Methanol Recovery water trap, reclaim thick methyl alcohol, pump into methanol wash tower methanol wash then, advance the fractionation of flash distillation separation column again and get the biofuel finished product.

3, according to claim 1,2 described with mixed fatty acid production biofuel method, it is characterized in that: esterifying agent is made up of 1.8% sulfuric acid, 0.2% sulfonic acid, 98% methanol mixed.

4, according to claim 1,2 described with mixed fatty acid production biofuel method, it is characterized in that: washing is the methyl alcohol of content 97% with methyl alcohol.