CN102320707A - Method for treating waste water generated in production process of alcohol by fermenting - Google Patents

Abstract

The invention discloses a method for treating waste water generated in the production process of alcohol by fermenting. The method comprises the following steps of: (1) performing high-temperature contact type anaerobic fermentation on the generated alcohol waste water; (2) performing centrifugal separation; (3) performing medium-temperature combined upflow anaerobic sludge blanket (UASB) anaerobic fermentation on the clear solution obtained through separation; (4) separating methane, sludge and clear solution from the waste water subjected to anaerobic fermentation under the action of a triphase separator on the upper part of an anaerobic fermentor; (5) performing sequencing batch reactor (SBR) normal-temperature oxygen-consuming fermentation on the clear solution obtained through separation in the step (4), settling again after fermentation, and separating out the clear solution; and (6) applying the clear solution obtained through separation in the step (5) to alcohol process recycle. In a 'waste water and waste treatment-resource comprehensive utilization' circular economy standardization system established by the invention, natural resources and secondary energy sources are utilized reasonably by comprehensively utilizing resources, saving energy, reducing consumption and saving water, so that the natural resources and the energy sources can be utilized most reasonably and discharge of wastes and pollutants can be reduced.

Description

A kind of fermentation alcohol production wastewater treatment method

Technical field

The present invention relates to a kind of sewage water treatment method, particularly a kind of wastewater treatment method that is used for grain distillery's fermentation alcohol production.

Background technology

In the ethanol produce, water is important material, according to raw material different (cassava, corn, barley and rice etc.), adds the water ratio and has nothing in common with each other, and is general about 3 times of raw material total amount.To produce 100000 tons grain distillery per year is example, year consumes a process water to reach ten thousand stere more than 100, about 130 ten thousand steres of contracts alcohol waste water.

In order to economize on resources; Improve the comprehensive utilization ratio of resource; China also explicitly calls for the alcohol industry resource consumption index; According to the GB/T18916.7-2004 standard, requiring preferably to alcohol water intaking quota (comprise process water, produce auxiliary water etc.), level is that ton alcohol water withdrawal is less than 40 tons.At present the water withdrawal of general enterprise is much in this index, and the method that reduces water withdrawal is except for example adopting technology such as high gravity fermentation, and the repeating utilization factor that improves water is a very important approach.

Fermentation alcohol industry belongs to the conventional industries of highly energy-consuming, high pollution, low output, poor benefit.Country is more and more stricter to the control of wastewater from fermentation industry discharging.For the consumption that reduces raw material, water, the energy and the discharging of waste water, fermentation industry requires to adopt process for cleanly preparing.For fermentation industry, reduce water consumption and wastewater discharge, reclaiming wherein useful sub product simultaneously is to improve the environment performance and improve the very effective approach of business economic benefit.

Alcohol waste water is a kind of organic waste water of high density, and COD content is up to 5～70,000 mg/L, if in linely go in the external environment, can seriously cause rich the supporting of water body and contaminate environment.Seeing that the ethanol produce water consumption is too many.Water saving has strategic importance, has both alleviated the imbalance between supply and demand of water resources, alleviates the pressure of urban development to environment, reduces the production run cost again, realizes the sewage low emission.

Summary of the invention

Goal of the invention: the objective of the invention is in order to solve the deficiency of prior art, provide a kind of and reduce cost, the fermentation alcohol production wastewater treatment method of conserve water resource.

Technical scheme: in order to realize above purpose, a kind of fermentation alcohol production wastewater treatment method of the present invention, the concrete steps of this technology are following:

(1) alcohol waste water that produces is carried out high temperature contact anaerobically fermenting, 55 ℃～60 ℃ of leavening temperatures, 8～10 days sealed fermenting time; Under the anaerobic state, the organism of the most readily biodegradables generation biogas that is decomposed in the waste water; COD is reduced to about water outlet 5000mg/L by 5～70,000 mg/L of water inlet;

(2) alcohol waste water behind the high temperature contact anaerobically fermenting is carried out spinning, isolate mud and clear liquid; Mud becomes fuel or fertilizer;

(3) the isolated clear liquid of step (2) is carried out middle temperature combination flow lifting type UASB anaerobically fermenting; Leavening temperature 36-38 ℃;

(4) through the waste water behind the anaerobically fermenting under the effect of anaerobically fermenting device top triphase separator, separate biogas, sedimentation mud, isolate clear liquid;

(5) the isolated clear liquid in the step (4) is carried out SBR normal temperature oxygen consumption fermentation, sedimentation once more after the fermentation, isolate the stillness of night; COD is reduced to below the water outlet 100mg/L by the 1500mg/L of water inlet;

(6) the isolated stillness of night in the step (5) being used for alcohol technology returns and joins.

Among the present invention, at first to carry out the tame and docile of mud and educate, tame and docile and to educate method and be:

Become ripe sludge directly to throw in to anaerobism or oxygen consumption fermentor tank from " the kind mud " of market purchasing or congeniality waste water treatment plant and inoculate, inoculum size is fermentor tank volumetrical 3O%, a small amount of charging in edge joint kind limit; Press the l0% of flow～20% and add waste water, make active sludge microorganism adapt to existing water quality condition gradually, reach requirement after, continue to increase waste water proportion again.The percentage of each increase is 10%～20% of a flow, and treats to continue to increase after mikrobe adapts to consolidation again, till reaching the full load processing power; Tame and docile and bring out anaerobic activated sludge.

 

Based on the above-mentioned mud of educating of taming and dociling, the concrete grammar of high temperature contact anaerobically fermenting is following among the present invention:

In anaerobic jar, put into tank volume 40%～50% anaerobic activated sludge, charging behind cooling waste water temperature to 40～50 ℃, intermittent feeding 10 hours at interval, each inlet amount is less than 10% of tank volume, feed time 1.5-2.5 hour; In 55 ℃～60 ℃ closed environment, fermented 8～10 days; With 8～10 days was one-period; For increasing the touch opportunity of mikrobe and raw material, accelerate fermenting speed, improve biogas output, each fermentation period carries out 8～10 circulations and stirs, and is controlled at 1.5～2 hours at every turn.Fermentation period detection of end water outlet pH value, if pH is lower than 7.0, prolong fermentation time until pH greater than 7.0, complete to guarantee anaerobically fermenting.

 

Among the present invention, adopt the continuous sample introduction mode in the temperature combination flow lifting type UASB anaerobic fermentation method in said, water inlet pH value is 6.7～7.5, and suspended substance is less than 1000mg/L, 30～40 ℃ of inflow temperatures; 36-38 ℃ of control leavening temperature; Middle temperature combination flow lifting type UASB anaerobic fermentation method efficiently moves formation and the maintenance that key is a large amount of granule sludges; Therefore strict control water inlet COD is between 4000～5000mg/L; Operating temperature is constant to be no more than 2 ℃ in the daily fluctuation scope; Detect water outlet volatile acid (VFA < 300mg/>L) simultaneously, can form or form bigger granule sludge as early as possible like this., under the effect of anaerobically fermenting device top triphase separator, separate biogas, sedimentation mud, clarify out clear liquid through the waste water behind the anaerobically fermenting.

 

The major portion of the method (batch type aerobic activated sludge process) of SBR normal temperature oxygen consumption fermentation is among the present invention:

(1) water distribution: the stillness of night and clear water after distribution reservoir is put into temperature combination flow lifting type UASB anaerobically fermenting simultaneously, the water distribution quantity of clear water is 18%～22% of a Total Water, guarantees that the laggard SBR water inlet of water distribution COD content is between 1450mg/L～1550mg/L; Preaeration in 1.5 hours is carried out in water distribution;

(2) SBR water inlet: adopt the intermittent water inflow mode, each flooding quantity is an oxygen consumption fermentor tank volumetrical 15%, and the oxygen consumption sludge quantity is 40～50% of a tank volume;

(3) arrange SBR working time: specific as follows: intake 1 hour, aeration 3 hours static 3 hours, was strained water 1 hour;

(4) data in the monitoring SBR operational process: in half a hour dissolved oxygen amount is detected after (a) half a hour, aeration finish before each aeration, if dissolved oxygen amount is lower than 3mg/L, then carry out aeration simultaneously in water inlet, promptly aeration time increases to 4 hours; If dissolved oxygen amount greater than 7mg/L, then reduces aeration time, increase rest time.(b) every interval, was discharged mud and is back in the high temperature contact anaerobically fermenting if sludge concentration greater than 50% o'clock, should be carried out spoil disposal half a hour before the aeration end, sampling of wastewater detected sludge concentration in 24 hours.

Beneficial effect: the present invention compared with prior art has the following advantages:

1, makes up " waste water, waste treatment---comprehensive utilization of resources " recycling economy Standardization System; Comprehensive utilization through resource and energy-conservation, consumption reduction, water saving; Rationally utilize natural resources and secondhand energy; Reach the rationalization of natural resources and energy utilization, reduce the discharging of refuse and pollutent.

2, estimate to produce biogas 2500 ten thousand steres per year through alcohol waste water anaerobic treatment process, be equivalent to about 25000 tons of raw coal; Produce about 60,000 tons of mud per year, be equivalent to 12000 tons of raw coal.Add up to year to economize on 37000 tons in raw coal.Owing to after boiler is used biogas, mud and raw coal multifuel combustion instead, can reduce discharging CO every year ₂About 4800 tons, SO ₂About 240 tons of about 320 tons, flue dust, and prevented greenhouse gases biogas and emission of carbon-dioxide.

3, alcohol waste water reaches discharging standards after advanced treatment finishes, and water up to standard is used for ethanol produce water and the auxiliary water of circulation, realizes sewage zero-discharge.Since the use of recovering and using technology of water up to standard, year saving water 400 ten thousand steres, 9,600,000 yuan of year saving water resources taxes.Ratio of water recycle reaches more than 90% in the ethanol produce, and the water consumption index can reach leading domestic level.

Description of drawings

Fig. 1 is a schema of the present invention.

Embodiment:

Below in conjunction with accompanying drawing and specific embodiment; Further illustrate the present invention; Should understand these embodiment only be used to the present invention is described and be not used in the restriction scope of the present invention; After having read the present invention, those skilled in the art all fall within the application's accompanying claims institute restricted portion to the modification of the various equivalent form of values of the present invention.

Embodiment

A kind of fermentation alcohol production wastewater treatment method, the concrete steps of this technology are following:

(1) the tame and docile earlier mud of educating carries out high temperature contact anaerobically fermenting to the alcohol waste water that produces then; The method of high temperature contact anaerobically fermenting is: in anaerobic jar, puts into tank volume 40% and tames and dociles the anaerobic activated sludge that brings out, and charging after the cooling waste water temperature to 40 ℃, intermittent feeding 10 hours at interval, each inlet amount is less than 10% of tank volume, feed time 2 hours; Fermentation is 9 days in 55 ℃ ℃ closed environment; With 9 days was one-period; For increasing the touch opportunity of mikrobe and raw material, accelerate fermenting speed, improve biogas output, each fermentation period carries out 8 circulations and stirs, and is controlled at 2 hours at every turn.Fermentation period detection of end water outlet pH value, if pH is lower than 7.0, prolong fermentation time until pH greater than 7.0, complete to guarantee anaerobically fermenting.

(2) alcohol waste water behind the high temperature contact anaerobically fermenting is carried out spinning, isolate mud and clear liquid;

(3) the isolated clear liquid of step (2) is carried out middle temperature combination flow lifting type UASB anaerobically fermenting; In the present embodiment, adopt the continuous sample introduction mode in the middle temperature combination flow lifting type UASB anaerobic fermentation method, water inlet pH value is 6.7, and suspended substance is 850mg/L, 35 ℃ of inflow temperatures; 36 ℃ of control leavening temperatures;

(4) through the waste water behind the anaerobically fermenting under the effect of anaerobically fermenting device top triphase separator, separate biogas, sedimentation mud, isolate clear liquid;

(5) the isolated clear liquid in the step (4) is carried out SBR normal temperature oxygen consumption fermentation, sedimentation once more after the fermentation, isolate the stillness of night;

In the fermentation of SBR normal temperature oxygen consumption, during water distribution: in distribution reservoir, put into the stillness of night after clear water and temperature make up flow lifting type UASB anaerobically fermenting simultaneously, the water distribution quantity of clear water is 18% of a Total Water, and the laggard SBR water inlet of water distribution COD content is between 1450mg/L～1550mg/L; Preaeration in 1.5 hours is carried out in water distribution; In the fermentation of SBR normal temperature oxygen consumption, the intermittent water inflow mode is adopted in the SBR water inlet, and each flooding quantity is an oxygen consumption fermentor tank volumetrical 15%, and the oxygen consumption sludge quantity is 42% of a tank volume; In the fermentation of SBR normal temperature oxygen consumption, SBR is specific as follows working time: intake 1 hour, aeration 3 hours static 3 hours, was strained water 1 hour.

(6) the isolated stillness of night in the step (5) being used for alcohol technology returns and joins.

Claims (1)

1. fermentation alcohol production wastewater treatment method, it is characterized in that: the concrete steps of this technology are following:

(1) alcohol waste water that produces is carried out high temperature contact anaerobically fermenting, leavening temperature 55-60 ℃, 8～10 days sealed fermenting time;

(2) alcohol waste water behind the high temperature contact anaerobically fermenting is carried out spinning, isolate mud and clear liquid;

(3) the isolated clear liquid of step (2) is carried out middle temperature combination flow lifting type UASB anaerobically fermenting; Leavening temperature 36-38 ℃;

(4) through the waste water behind the anaerobically fermenting under the effect of anaerobically fermenting device top triphase separator, separate biogas, sedimentation mud, isolate clear liquid;

(5) the isolated clear liquid in the step (4) is carried out SBR normal temperature oxygen consumption fermentation, sedimentation once more after the fermentation, isolate the stillness of night;

(6) the isolated stillness of night in the step (5) being used for alcohol technology returns and joins.

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