CN103408188B - GZBS refuse leachate treatment method - Google Patents

Abstract

The invention discloses a GZBS (Biochemical Crosslinking Treatment System) refuse leachate treatment method which comprises two parts including a biochemical treatment section and a cross linking reaction treatment section. The method comprises the following steps: (1), a refuse leachate sequentially passes through a mixing pool and a rotary type efficient biological reactor for reaction and then enters a gradient biochemical aeration tank and a biochemical sedimentation tank; (2) water flowing through the sedimentation tank enters a mechanical stirring pool, a compound cross-linking agent is added at the moment, and the water is discharged through the sedimentation tank after reaction. The GZBS refuse leachate treatment method provided by the invention is mainly applied to treatment of the leachate produced by a refuse burning (power generation) factory in which the Integrated Wastewater Discharge Standard and GB8978-1996 are executed.

Description

A kind of GZBS refuse leachate treatment method

Technical field

The present invention relates to landfill leachate treatment field, specifically a kind of GZBS refuse leachate treatment method.

Background technology

Treatment process for the current domestic main employing of percolate of waste incineration (generating) the factory generation of execution " integrated wastewater discharge standard " " GB8978-1996 " is that leading portion adopts " biochemistry+MBR ", and back segment adopts " nanofiltration or reverse osmosis ".Leading portion biochemical process is to adopt A2/O, MBR in the majority with the form of external film again in recent years; Rear end " nanofiltration or reverse osmosis " adopts DTRO film or rolled film substantially.

Mainly there is following problem in domestic conventional garbage leachate treatment technology: (1) energy consumption is large: percolate feature is TN and NH ₃-N is high, and A2/O biochemical treatment denitride technology and theory are based upon lower concentration TN and NH ₃on-N basis, for high density TN and NH ₃-N adopts the denitrogenation of A2/O system, lacks ripe Systems Theory, and mostly in engineering is use for reference lower concentration TN and NH ₃-N is theoretical.Due to TN and NH in percolate ₃-N concentration is high, in order to improve processing efficiency, must increase oxygen-supplying amount and improving sludge concentration, and traditional activated sludge process aerobic sludge is when sludge concentration reaches more than 6000mg/L, and muddy water is difficult to be separated.For effectively improving sludge concentration, adopting membrane filtration to substitute biochemical second pond, becoming inevitable in percolate biochemical treatment section.Simultaneously remove according to traditional theory the oxygen that 1g nitrogen needs more than 3g, biochemical system power consumption is high for this reason.(2) run difficulty large: A(anaerobic denitrifying in A2/O technology) with O(aerobic nitrification) operational conditions of unit own differs greatly.Tradition denitrogenation theory thinks that A unit is based on heterotrophic bacterium, and mud is shorter for age, and O unit is based on autotrophic bacteria, and mud is longer for age.Due in A2/O technology without mudpan, in actual motion, A section microbes enters O section with sewage, and enters A section by the O section microorganism that MBR retains by backflow, and therefore existing system is difficult to each section of Effec-tive Function.In addition, in A2/O technology, sewage temperature, basicity, organic carbon concentration and dissolved oxygen concentration all can impact system stable operation and treatment effect.For this reason, biochemical system steady running is realized in Practical Project very big.(3) supplementary carbon source is needed: percolate carbon-nitrogen ratio imbalance in general.Adopt A2/O to realize denitrogenation, require that the ratio of carbon source and total nitrogen generally reaches 6 ~ 8.So high carbon-nitrogen ratio, generally only uses the initial stage to reach requirement reluctantly in refuse landfill, and for landfill leachate treatment engineering of speaking more greatly absolutely, the denitrification effect that realize ideal, must mend from the external world and throw carbon source.(4) pollution transportation: nanofiltration or reverse osmosis are in fact pollutent concentration processs, the current overwhelming majority of pollutent retained through nanofiltration or reverse osmosis takes disposal options to be returned by concentrated solution to be sprayed onto refuse landfill, in theory, residual pollutent is not effectively decomposed.Although relevant technologies personnel are seeking the thorough treatment technology of concentrated solution at present, in actual application, its cost and operation scheme are also also existing some problems.(5) cost is high: as membrane separation technique, and the replacing carrying out film after using for some time is necessary.From current domestic Practical Project operation conditions, within 2 ~ 3 years, once need change film.(6) technique specific aim is not enough: " GB8978-1996 " " integrated wastewater discharge standard " discharge index is to TN no requirement (NR), TN removes in the lump by " nanofiltration or reverse osmosis " technology that existing treatment process adopts while process COD, shorten the replacement cycle of " nanofiltration or reverse osmosis " membrane module, add processing cost.

Summary of the invention

In order to solve the above-mentioned technical problem existed in prior art, the invention provides a kind of GZBS refuse leachate treatment method, being made up of biochemical treatment section and crosslinking reaction processing section two part: comprise the steps:

(1) percolate is entered gradient biochemical aeration tank and biochemical sedimentation basin successively after mixing pit and the reaction of rotary type efficient bio-reactor;

(2) water after settling tank enters mechanical agitated pool, now adds multiple crosslinking agent; Discharge after settling tank after reaction.

Further, add microbial growth promoters when rotary type efficient bio-reactor reacts, the biochemical treatment microorganism that to set up with genus bacillus group be dominant bacteria.

Further, this microbial growth promoters is pressed powder, is wherein rich in Ca ²⁺, Mg ²⁺, Si ²⁺deng the trace element of genus bacillus growth needs.

Further, described multiple crosslinking agent is aluminum contained compound, is preferably composite salt aluminium.

Further, at process water inlet leachate quality CODcr:40000 ~ 50000mg/L, TN:2500 ~ 3000mg/L, NH ₃during the percolate of-N:1500 ~ 2000mg/L, process out water management at CODcr:600 ~ 1000mg/L, TN:80 ~ 200mg/L, NH ₃the level of-N:<10mg/L;

Biochemical treatment section main control parameters:

(1) rotary high-efficient bio-reactor: rotating speed: 4 ~ 6r.p.m, processing load: 2 ~ 2.5kgBOD/m2/d;

(2) biochemical aeration tank: the process residence time (HRT): 240 hours;

(3) sludge loading (F/M): 0.5 ~ 0.8kgBOD/kgMLSS/.d;

(4) sludge concentration (MLSS): 8000 ~ 10000mg/L;

(5) aeration rate (Q): 80 ~ 120m3/kgBOD;

(6) biochemical sedimentation basin: 15 ~ 25 m ³/ m ²/ d.

The percolate process that waste incineration (generating) factory that GZBS refuse leachate treatment method of the present invention is mainly used in execution " integrated wastewater discharge standard " " GB8978-1996 " produces.

Accompanying drawing explanation

Fig. 1 is the schema of GZBS refuse leachate treatment method of the present invention.

Embodiment

Below in conjunction with accompanying drawing, the invention will be further described.

As shown in Figure 1, GZBS (Biochemical Crosslinking Treatment System), also known as gene biological treatment system, to domestic and international refuse leachate treatment technology repeated screening, optimization, basis is being invented,

GZBS refuse leachate treatment method of the present invention is made up of biochemical treatment section and crosslinking reaction processing section two part.

Biochemical treatment section is continuing to use on traditional active sludge framework basis, microbial growth promoters is adopted to form the treatment technology being dominant bacteria decomposing pollutant with subtilis (Bacillus), system is made up of rotary type efficient bio-reactor, gradient biochemical aeration tank, biochemical sedimentation basin and corresponding return-flow system, can be COD cr:4000 ~ 20000mg/L, TN:1000 ~ 3500mg/L, NH by original concentration after this section of process ₃the percolate of-N:800 ~ 3000mg/L, processes out water management at CODcr:600 ~ 1000mg/L, TN:80 ~ 200mg/L, NH ₃the level of-N:<10mg/L.

Microbial growth promoters, the biochemical treatment microorganism that to set up with genus bacillus group be dominant bacteria, this microbial growth promoters is pressed powder, is wherein rich in Ca ²⁺, Mg ²⁺, Si ²⁺deng the trace element of genus bacillus growth needs.

Because garbage burning factory leachate contamination load is high, this technology is refluxed by multiple spot in biochemical treatment section, control corresponding reflux ratio, regulate the means such as aeration rate, carbon source in pollutent is decomposed rapidly, utilize simultaneously and control the feature that genus bacillus has simultaneous removing nitrogen system, sulphur system pollutent, realize COD, BOD, TN, NH of more than 90% in biochemical section ₃the contamination index such as-N, TP removes, and ensures biochemical sedimentation basin water outlet CODcr<1000mg/L, BOD ₅<100mg/L, TN<200mg/L, NH ₃the target of-N<10mg/L, TP<1mg/L.

The pollutent that percolate after biochemical treatment forms COD pollution load is mainly humic acid organic substances, and the method that tradition removes pollutent is by adding oxygenant, makes macromole organic pollutant change into carbonic acid gas and water, realizes the object removing pollutent.The present invention, in back-end processing, adopts the mode adding linking agent, controls certain reaction conditions simultaneously, organic pollutants is cross-linked with each other, is polymerized, and forms the larger molecular organics that solubleness is less, is then realized the removal of pollutent by precipitation.Linking agent adopts aluminum contained compound, controls more than 2 hours reaction times, under the condition of PH5.5 ~ 6.5, realizes the target of process water outlet CODcr<400mg/L.

GZBS refuse leachate treatment method main control parameters of the present invention:

Water inlet leachate quality CODcr:40000 ~ 50000mg/L, TN:2500 ~ 3000mg/L, NH ₃the percolate of-N:1500 ~ 2000mg/L is benchmark, processes out water management at CODcr:600 ~ 1000mg/L, TN:80 ~ 200mg/L, NH ₃the level of-N:<10mg/L;

Biochemical treatment section main control parameters:

(1) rotary high-efficient bio-reactor part: rotating speed: 4 ~ 6r.p.m, processing load: 2 ~ 2.5kgBOD/m2/d;

(2) biochemical aeration tank: the process residence time (HRT): 240 hours;

(3) sludge loading (F/M): 0.5 ~ 0.8kgBOD/kgMLSS/.d;

(4) sludge concentration (MLSS): 8000 ~ 10000mg/L;

(5) aeration rate (Q): 80 ~ 120m3/kgBOD;

(6) biochemical sedimentation basin: 15 ~ 25 m ³/ m ²/ d;

Biochemical section effluent index: CODcr:600 ~ 1000mg/L, TN:100 ~ 200mg/L, NH ₃-N:1 ~ 10mg/L.

Crosslinking Treatment section main control parameters:

(1) multiple crosslinking agent: composite salt aluminium;

(2) crosslinked dosage: 2 ~ 4kg/kgCOD;

(3) reaction times: 2 ~ 4 hours;

(4) PH:5 ~ 6 are reacted;

(5) sedimentation time: 4 ~ 6 hours;

Effluent index: CODcr:300 ~ 450mg/L, TN:100 ~ 200mg/L, NH ₃-N:1 ~ 10mg/L.

GZBS refuse leachate treatment method advantage of the present invention is as follows:

(1) major function of unit is related to this technology, the load of carrying, operating parameter quantize one by one.Actual motion shows, influent quality COD at 35000 ~ 50000mg/L, TN under 1200 ~ 3500mg/L condition, by change operating parameter, the treatment effect all can realized ideal.

(2) run simple effects to stablize: the treatment technology that it is dominant bacteria with bacillus subtilis bacillus that biochemical treatment section adopts.Because bacillus subtilis bacillus life condition requires lower, biochemical system, in day-to-day operation process, only needs dissolved oxygen to control at below 1.0mg/L, runs simple comparatively speaking.Aftertreatment section adopts thinking contrary to regular oxidation decomposing pollutant, by adding linking agent, water pollutant molecule being polymerized mutually, forming the material that molecular weight is larger, thus the contamination transform be dissolved in the water is become water-fast throw out, thus realize the removal of water pollutant.The linking agent reaction conditions adopted due to this technology is comparatively gentle, and simple to operate, can, according to bio-chemical effluent Pollutant levels determination linking agent dosage, be easy to control.

(3) energy consumption is low: genus bacillus has good throwing out, and the organic debris in water body can be sticked together mutually by this throwing out, forms zoogloea, undertakes the task of oxygenolysis, be combined into by organism cotton-shaped.When this characteristic efficiently solves Wastewater Treated by Activated Sludge Process waste water, film (MBR) must be adopted in mud high density situation to carry out the problem of mud-water separation.Service data shows, when under the condition of sludge concentration at 15000mg/L, adopts settling tank, still better can realize mud-water separation.The power consumption of biochemical system ton water is at 8 ~ 10 degree.

(4) complete decomposition is polluted: biochemical system and advanced treatment system all adopt the sewage disposal technology of decomposing pollutant, fundamentally removal of pollutants.

(5) without foul smell secondary pollution: genus bacillus utilizes its abundant enzyme, intensive decomposition nitrogen system, sulphur system pollutent eliminate the peculiar smell produced in sewage treatment process while purifying water body..

(6) mud generation is few: " GZBS-2 " technology is in landfill leachate treatment process, and the sludge quantity of generation is less.With influent quality CODcr35000 ~ 50000mg/L, TN1500 ~ 3000mg/L for benchmark, the concentrated front sludge quantity got rid of by settling tank, biochemical system section is 15 ~ 20% of the process water yield, and advanced treatment section is 10 ~ 15% of the process water yield, and the first sludge quantity of whole system is 25 ~ 30% of the process water yield.

(7) processing cost is low: this system ton cost of water treatment is 45 ~ 50 yuan.

Claims (4)

1. a GZBS refuse leachate treatment method, is made up of biochemical treatment section and crosslinking reaction processing section two part: comprise the steps:

(1) percolate is entered gradient biochemical aeration tank and biochemical sedimentation basin successively after mixing pit and the reaction of rotary type efficient bio-reactor;

(2) water after biochemical sedimentation basin enters mechanical agitated pool, now adds multiple crosslinking agent; Discharge after settling tank after reaction;

Wherein, add microbial growth promoters when rotary type efficient bio-reactor reacts, the biochemical treatment microorganism that to set up with genus bacillus group be dominant bacteria; This microbial growth promoters is pressed powder, is wherein rich in Ca ²⁺, Mg ²⁺, Si ²⁺deng the trace element of genus bacillus growth needs.

2. GZBS refuse leachate treatment method as claimed in claim 1, is characterized in that: described multiple crosslinking agent is aluminum contained compound.

3. GZBS refuse leachate treatment method as claimed in claim 2, is characterized in that: described aluminum contained compound is composite salt aluminium.

4. GZBS refuse leachate treatment method as claimed in claim 1, is characterized in that: at process water inlet leachate quality CODcr:40000 ~ 50000mg/L, TN:2500 ~ 3000mg/L, NH ₃during the percolate of-N:1500 ~ 2000mg/L, process out water management at CODcr:600 ~ 1000mg/L, TN:80 ~ 200mg/L, NH ₃the level of-N:<10mg/L;

Biochemical treatment section main control parameters:

(1) rotary high-efficient bio-reactor: rotating speed: 4 ~ 6r.p.m, processing load: 2 ~ 2.5kgBOD/m2/d;

(2) biochemical aeration tank: the process residence time (HRT): 240 hours;

(3) sludge loading (F/M): 0.5 ~ 0.8kgBOD/kgMLSS/.d;

(4) sludge concentration (MLSS): 8000 ~ 10000mg/L;

(5) aeration rate (Q): 80 ~ 120m3/kgBOD;

(6) biochemical sedimentation basin: 15 ~ 25 m ³/ m ²/ d.