A kind of is the method for main material production biogas with the cellulose ethanol sub product
Technical field
The invention belongs to the biogas production technical field, particularly a kind of is main raw material with the cellulose ethanol sub product, and the starch ethanol waste liquid is the method that auxiliary material is produced biogas.
Background technology
Utilize stalk to produce ethanol, promptly cellulose ethanol reduces CO2 emissions for solving energy dilemma, solves straw from village and pollutes, and increases farmers' income, and realizes that Sustainable development has great significance.
In the cellulose ethanol production process, need carry out pre-treatment to stalk.Up to the present the pretreatment process that occurs mainly contains: acid system, alkaline process, physics and chemistry method and biological process.Verified with practice through a large amount of experiments: the steam explosion method for pretreating is compared advantages such as having simple, efficient, relative environmental protection with other method, its shortcoming is to lose in the treating processes a large amount of semicelluloses.Semicellulose is decomposed into furfural, acetate, low molecule organic matters such as formic acid under the effect of HTHP.
In the steam explosion preprocessing process; The degradation product of a large amount of semicelluloses; And small amount of fibers is plain and the lignin degradation thing can follow steam from the explosion raw material, to separate, and reclaims through the condensing and recycling tower, forms cellulose ethanol acid, high COD and produces sub product---cellulose ethanol waste liquid.If directly enter the river, will cause severe contamination to environment, if reclaim, cost and technical difficulty are all too big.If can it be made full use of, be converted into biogas, not only environmental protection, can produce more renewable resourcess again.
But, through the sub product waste liquid that reclaims, have strongly-acid, high COD, high TSS, and low N, P and micronutrient levels, if directly carry out anaerobic treatment, difficulty is very big and cost is higher.If can pass through the certain process adjustment, and adjust suitable processing parameter, treatment effect can significantly improve.
Starch produces the fermented distilled raffinate of a large amount of high nutrition of protein-high in process of production, through after the spinning; Sticky part is processed the DDGS high protein feed through super-dry, and supernatant then becomes protein-high, high concentrated organic wastewater; If directly carry out anaerobic treatment; The N of water outlet, P, micro-equal size is often higher, causes waste and body eutrophication.
If after cellulose ethanol production wastewater and starch ethanol waste water mixed by a certain percentage; Carry out anaerobic treatment, not only make each constituent content of waste water moderate, and the biogas amount also can obviously increase; This also has positive effect for reducing by two kinds of waste water individual curing costs.
In the bioenergy field, ethanol is occupied an leading position, and biogas also occupies critical positions.The major ingredient of biogas is a methane, and content is 55% ~ 70%.Methane calorific value 35.9MJ/m
3, the biogas calorific value is at 20 ~ 25 MJ/m
3Between, producing a large amount of heat during burning, every cube of biogas calorific value is equivalent to 3Kg mark coal.Therefore, it also is one of main developing direction as new forms of energy.
And up to the present, have no patent and report to relate to this method and produce biogas.
Summary of the invention
The object of the present invention is to provide a kind of is the method for raw material production biogas with cellulose ethanol and starch ethanol production waste liquid mixed solution; The cellulose ethanol waste liquid is main carbon source; The starch ethanol waste liquid is a major nitrogen source; This method can make full use of two kinds of effective constituents in the waste liquid, reduces by two kinds of cost for wastewater treatment.
The present invention realizes that through following technical scheme its concrete steps are following:
(1) the vapor recovery water of condensation that stalk explosion pretreatment process in the cellulose ethanol production process is produced behind 80 order mesh screens, carries out flocculation sediment by a certain amount of adding flocculation agent, removes impurity and portion C OD, makes cellulose ethanol condensation waste liquid;
(2) cellulose ethanol condensation waste liquid and the starch ethanol waste liquid with step (1) gained mixes by 8 ~ 10 : 1, with quicklime adjustment pH value to 4.0 ~ 6.0, makes mixed waste liquor;
(3) cellulose ethanol production wastewater of enzyme Workshop Production waste water, boiler shop factory effluent, process advanced treatment being crossed mixes by 1 ﹕, 1 ﹕ 2, makes composite waste, and its COD is lower than 3000mg/L;
(4) with the composite waste of step (2) gained mixed waste liquor with (3) gained, mix by 1 : 2 ~ 4, process the final blending waste liquid, its COD is at 10000 ~ 20000mg/L;
(5) with the final blending waste liquid of step (4) gained, in equalizing tank, regulate pH to 4.5 ~ 6.5 with quicklime;
(6) waste liquid with step (5) gained passes through steam heater, and temperature is heated to 35 ℃ ± 2 ℃, is continuously pumped into the EGSB reactor drum then and carries out anaerobically fermenting.35 ℃ ± 1 ℃ of control leavening temperature, reflux ratio is 2 ~ 5 : 1, and hydraulic detention time (HRT) is 40h ~ 60h, and the biogas that anaerobically fermenting is produced measures with gas meter, utilizes the biogas cabinet to collect.
The vapor recovery water of condensation that stalk explosion pretreatment process produces in the cellulose ethanol production process of the present invention is: the vapor recovery water of condensation that stalk produces when carrying out pre-treatment.
Starch ethanol waste liquid of the present invention is: alcohol fermented beer is through the raffinate after distilling, the supernatant through obtaining after centrifugal again.
Flocculation agent of the present invention can be Poly aluminum Chloride (PAC) or other flocculation agent.
Equipment used in the present invention is conventional general production unit, need not specialized apparatus.
Enzyme Workshop Production waste water used in the present invention is to be used to wash and the empty waste water that produces when disappearing tank body.
Boiler shop factory effluent used in the present invention is the waste water that produces when producing soft water.
The cellulose ethanol production wastewater of crossing through advanced treatment used in the present invention be cellulose ethanol waste water through anaerobism, aerobic treatment after, pass through the waste water behind the flocculation decoloration again.
Advantage of the present invention: efficiently solve the high concentrated organic waste liquid that produces in the cellulose ethanol production process and handle a difficult problem, and produce a large amount of biogas simultaneously, can effectively eat up part of the cellulose ethanol production cost; Also solve the processing difficult problem of the high nutrition waste water that starch ethanol produces in producing, realized making full use of of effective constituent in two kinds of waste water.Calculate by annual 10000 tons of cellulose ethanol output, can produce 6,000,000 side's biogas simultaneously, not only effectively solve the problem of utilizing stalk producd fibers ethanol to produce recontaminate, also solved the energy consumption of cellulose ethanol production self to a great extent.
The present invention fully utilizes cellulose ethanol and starch ethanol waste water and produces biogas, has not only reduced the cellulose ethanol cost for wastewater treatment, has made full use of the nutrition of starch ethanol waste water again, and the development of cellulose ethanol is had great significance.
Embodiment
Embodiment 1: adopt the small-sized EGSB reactor drum of self-control 24L, take present method, concrete steps are following:
(1) stalk carries out the water of condensation that the steam explosion pre-treatment produces, and adds Poly aluminum Chloride (PAC) by the amount of 0.1Kg/t and carries out flocculation sediment, removes impurity and portion C OD, obtains cellulose ethanol condensation waste liquid;
(2) cellulose ethanol condensation waste liquid and the starch ethanol waste liquid with (1) gained mixes by 10 : 1, and adjustment pH to 4.5 ~ 5.0 make mixed waste liquor;
(3) cellulose ethanol production wastewater of enzyme Workshop Production waste water, boiler shop factory effluent, process advanced treatment being crossed mixes by 1 ﹕, 1 ﹕ 2, makes composite waste, and the mixed waste liquor of step 2 and composite waste mix by 1 ﹕ 2;
(4) with the water of (3) gained with water-bath attemperation to 35 ℃ ± 1 ℃, regulate pH to 5.0 ~ 5.5 with quicklime;
(5) water with (4) pumps into the EGSB reactor bottom, and reflux ratio is 4 : 1, carries out anaerobically fermenting, hydraulic detention time 50 ~ 55h, EGSB reactor volume 24L;
(6) adopt draining water gathering of gas law to collect biogas the biogas that produces.
The result is following: 15 days total gas productions are 667L, and on average producing tolerance daily is 44.5L.
Embodiment 2: adopt the small-sized EGSB reactor drum of self-control 24L, take present method, concrete steps are following:
(1) stalk carries out the water of condensation that the steam explosion pre-treatment produces, and adds Poly aluminum Chloride (PAC) by the amount of 0.1Kg/t and carries out flocculation sediment, removes impurity and portion C OD, obtains cellulose ethanol condensation waste liquid;
(2) with (1) gained obtain cellulose ethanol condensation waste liquid and the starch ethanol waste liquid mixes by 8 : 1, the adjustment pH to 4.5 ~ 5.0, make mixed waste liquor;
(3) cellulose ethanol production wastewater of enzyme Workshop Production waste water, boiler shop factory effluent, process advanced treatment being crossed mixes by 1 ﹕, 1 ﹕ 2, makes composite waste, and the mixed waste liquor of step 2 and composite waste mix by 1 ﹕ 3;
(4) with the water of (3) gained with water-bath attemperation to 35 ℃ ± 1 ℃, regulate pH to 5.0 ~ 5.5 with quicklime;
(5) water with (4) pumps into the EGSB reactor bottom, and reflux ratio is 3 : 1, carries out anaerobically fermenting, hydraulic detention time 45 ~ 50h, EGSB reactor volume 24L;
(6) adopt draining water gathering of gas law to collect biogas the biogas that produces.
The result is following: 15 days total gas productions are 531L, and on average producing tolerance daily is 35.4L.