CN103922820A

CN103922820A - Efficient aerobic composting method for sludge

Info

Publication number: CN103922820A
Application number: CN201310009140.0A
Authority: CN
Inventors: 王树岩; 梁莹; 刘军; 刘圣; 王爱雪
Original assignee: BEIJING JINYUANDA ENVIRONMENT TECHNOLOGY Co Ltd
Current assignee: BEIJING JINYUANDA ENVIRONMENT TECHNOLOGY Co Ltd
Priority date: 2013-01-11
Filing date: 2013-01-11
Publication date: 2014-07-16

Abstract

The invention relates to an efficient aerobic composting method for sludge, wherein a sludge stirring tank, a sludge dewatering pump, a separation membrane sludge press filter, a belt conveyor, a mud cake crushing and mixing device, a sludge heating dryer, a bacterial mixing device and a transporter are provided. According to the present invention, the separation membrane sludge press filter is adopted to carry out sludge dewatering, wherein the mud cake moisture content is less than 60%; the mud cake is crushed and heated, and then is completely mixed with the fermenting composite bacteria, and then direct composting fermentation is performed in the case of no addition of any organic dry materials and back-mixing materials so as to substantially reduce the fermentation bin occupation area, shorten the winter composting time, improve the compositing success rate and the composting quality, and substantially reduce the project investment and the operation cost of the sludge aerobic fermentation system.

Description

A kind of mud high-efficiency aerobic compost method

Technical field

A kind of high-efficiency aerobic compost method that the present invention relates to the mud of municipal administration and Industrial Wastewater Treatment generation, makes sludge reduction, innoxious and resource utilization, belongs to field of environment engineering technology.

Background technology

In municipal administration and industrial sewage treating processes, produce a large amount of mud, this mud contains the plant nutrients such as a large amount of organic matters, nitrogen and phosphorus.At present, the disposal options of this mud comprises a variety of, as: landfill, burning, throwing sea and make construction material etc., and mud agricultural one of the best method of disposal avoided secondary pollution of turning harm into good beyond doubt.

Aerobic compost is a kind of effective ways of lignin-sludge, by compost, can make that excess sludge is innoxious, minimizing, resource utilization.

Compost is as a kind of bio-reaction system, and its speed of response and temperature have direct relation.Temperature directly affects the activity of heap internal microorganism, and the rising of heap temperature is mainly because of microorganism decomposing organic matter and releases heat.According to compost temperature changing conditions, composting process can be divided into four-stage, i.e. microorganism culturing phase, the phase of being rapidly heated, thermophilic fermentation phase, cooling and dewatering phase.First stage is the microorganism culturing phase, this stage microbial activities ability a little less than, therefore quantity of heat production is fewer, heats up more difficult.

Engineering practices show in a large number, and the first stage of compost is the key link that determines that can compost normally carry out.When temperature is lower, mud temperature is common also lower, and the sludge composting initial stage is difficult to heat up, and makes compost time lengthening, and compost floor space and compost cost improve greatly, in the northern area of China, because winter temperature is too low, cannot carry out normal compost fermentation.

Excess sludge of municipal sewage plant is water ratio approximately 97% after concentrated, and the dewatering type extensively adopting is at present belt filter press or centrifuge, dewatered sludge water ratio approximately 80%.Compost is as a kind of aerobe reactive system, and the air permeability of its speed of response and sludge body has direct relation, conventionally requires the water ratio of fermented sludge to be less than 60%.The dewatered sludge that domestic municipal sludge aerobic fermentation project built and under preparation is all 80% based on water ratio, need mix a large amount of organic siccatives and back-mixing material.Moisture percentage in sewage sludge is larger, and the weight and volume of mud is larger, and the siccative that need mix and back-mixing material are more, and the fermentation cabin volume taking is larger, and investment and running cost are higher.

The problem that prior art exists: domestic prior art sludge composting fermentation because of moisture percentage in sewage sludge too high, all need to add a large amount of siccatives, as wood chip, Pericarppium arachidis hypogaeae, corn stalk etc., add the weight of siccative to be generally 10% left and right of mud weight, also need to add 25～50% back-mixing material simultaneously, because of organic siccative density very little, fermented sludge volume is increased greatly, the fermentation cabin volume taking is very large, processes 1 ton of mud and makes an investment in more than 300,000 yuan, processes ton mud running cost over 180 yuan; In northern China, winter temperature is very low, and mud temperature approaches freezing point, and sludge fermentation has been difficult to.Based on above problem, the invention provides a kind of mud high-efficiency aerobic compost method,

Summary of the invention

The invention provides a kind of mud high-efficiency aerobic compost method, can greatly dwindle fermentation cabin floor space, shorten the compost time in winter, improve the success ratio of compost and the quality of composting production, greatly reduce construction investment and the running cost of sludge aerobic fermentation system.Be described as follows:

Accompanying drawing 1 is process flow sheet of the present invention.

1 sludge agitation pond, 2 is that sludge dewatering pump, 3 is that barrier film sludge filter press, 4 is that rotary conveyor, 5 is that cake crushing mixing machine, 6 is that mud heating, drying machine, 7 is that bacterial classification mixing machine, 8 is transport trolley.

The mud that municipal administration and industrial sewage treatment plant produce is squeezed into sludge agitation pond 1 with pump, sludge agitation pond 1 is furnished with stirrer, in sludge agitation pond 1, add chemical conditioner, under the strong stirring of the stirrer in sludge agitation pond 1, the abundant hybrid reaction of mud and chemical conditioner, with dehydration pump 2, mud is squeezed into barrier film sludge filter press 3 again, carry out sludge dewatering, moisture content of the cake is 50～60%, mud cake falls into rotary conveyor 4 automatically, and sent into cake crushing mixing machine 5 by rotary conveyor 4, cake crushing is become to small-particle, then fall into mud heating, drying machine 6, broken mud cake is heated to 40～50 ℃ in mud heating, drying machine 6, fall into again bacterial classification mixing machine 7, in bacterial classification mixing machine 7, according to sludge quantity, add in proportion sludge fermentation composite bacteria, the mud of having sneaked into compoiste fermented bacterial classification falls into transport trolley 8, finally be transported to fermentation place.In said process, do not add any siccative, do not add back-mixing material yet, only add a small amount of compoiste fermented bacterial classification, compoiste fermented bacterial classification is liquid, and weight ratio is 0.3～2 ‰, and 1000 tons of mud add 0.3～2 ton of liquid fermenting composite bacteria.The sludge temperature yeast phase that reaches a high temperature fast in fermentation cabin, fermenting process can complete in 15 days.

It is fuel that mud heating, drying machine 6 can utilize coal, gas or oil, produces hot blast, and mud is heated.When sludge dewatering is very difficult, when moisture content of the cake is greater than 60%, can strengthen hot blast rate, make dewatered sludge remove part moisture content, through the mud of mud heating, drying machine 6, water ratio is less than 60%, and temperature is 40～50 ℃, is highly susceptible to fermentation.

In external temperature higher than 10 ℃, moisture content of the cake is lower than 60% time, the technical process of Fig. 1 can be simplified, and mud, after dehydration, directly falls into rotary conveyor 4, send into cake crushing mixing machine 5, sludge fermentation composite bacteria is directly added in cake crushing mixing machine 5, and cake crushing mixes a step to be completed with bacterial classification, broken and sneak into the mud of compoiste fermented bacterial classification, directly fall into transport trolley 8, after be transported to fermentation place.Can, without mud heating, drying machine 6 and bacterial classification mixing machine 7, save working cost.

Beneficial effect

Beneficial effect of the present invention can calculate and find out by way of example: take that to process 1000 tons, mud that water ratio is 80% every day be example, prior art need add 100 tons of organic siccatives (water ratio is 10%) every day, need to add the back-mixing material of 500 tons (water ratio is 45%) simultaneously, the sludge quantity that enters fermentation cabin every day is 1600 tons/day (water ratio is 64.6%), fermentation time is 21 days, and in fermentation cabin, total sludge quantity is 33600 tons.As adopt the technology of the present invention, process the mud of same amount every day, because moisture content of the cake is 60%, do not add any organic siccative and back-mixing material simultaneously, the sludge quantity that enters fermentation cabin every day is only 500 tons, fermentation time is 15 days, in fermentation cabin, total sludge quantity is 7500 tons, 1/4 of not enough original technology, thus greatly dwindled fermentation place, saved construction investment, working cost also has obvious reduction simultaneously.

Embodiment

The mentioned technique according to the present invention, has adopted a microdiaphragm pressure filter, filtration area 30m ², process 35 tons of municipal sludges (water ratio is 97%) every day, produce 2.44 tons of dewatered sludges (moisture content of the cake is 57%) every day, with a 1.5m ³two ribbon cake crushing mixing machines sneak into by weight for millesimal liquid complex ferment microbial inoculum, under case without heating, in the room without heating, with bar buttress form compost, external temperature-12～3 ℃, fermented through 14 days; Identical control group test, mud cake, after fragmentation, is heated to 50 ℃, then sneaks into the complex ferment bacterial classification of same ratio, and compost under identical condition, reaches identical attenuation degree, lasts 9 days.

The mentioned technique according to the present invention, in south China municipal wastewater treatment plant, sewage disposal scale is 600,000 tons/day, and the mud of generation adopts diaphragm filter press dehydration, producing water ratio every day is 400 tons of 57～62% mud cakes, directly the outer sludge fermentation field of transporting to, adopts bar buttress mode compost, with turnover throwing machine, turns over throwing, in turning over throwing process, add complex ferment bacterial classification, do not add during the fermentation any organic siccative and back-mixing material, under least favorable temperature conditions, through 15 days, fermented in the winter time.

Claims

1. a mud high-efficiency aerobic compost method, is characterized in that comprising sludge agitation pond (1), sludge dewatering pump (2), barrier film sludge filter press (3), rotary conveyor (4), cake crushing mixing machine (5), mud heating, drying machine (6), bacterial classification mixing machine (7), transport trolley (8);

2. a kind of mud high-efficiency aerobic compost method as claimed in claim 1, is characterized in that the water ratio of the dewatered sludge for fermenting is less than 60%;

3. a kind of mud high-efficiency aerobic compost method as claimed in claim 1, is characterized in that not adding any organic siccative and back-mixing material, and only adding weight ratio is 0.3～2 ‰ liquid fermenting composite bacteria;

4. first a kind of mud high-efficiency aerobic compost method as claimed in claim 1, is characterized in that, by cake crushing, making mud be easy to heating and fermentation;

5. a kind of mud high-efficiency aerobic compost method as claimed in claim 1, is characterized in that when north of china in winter temperature is lower, adopts heating, drying machine that mud is heated to 40～50 ℃ in advance, can significantly accelerate fermenting speed.