The leachate processing method of a kind of circulated backfilling and artificial swamp coupling and facility thereof
Technical field
The invention belongs to environment protection, technical field of sewage, be specifically related to a kind of consumer waste landfill percolate treatment process and facility thereof.
Background technology
Percolate is the secondary pollution that the garbage loading embeading process produces, and is a kind of high concentrated organic wastewater of complicated component, is mainly derived from the interior moisture of precipitation and landfill refuse itself, and its pollution to environment is one of topmost environmental problem of landfill yard.It can polluted-water, soil, atmosphere etc., makes surface water body anoxic, water quality deterioration, eutrophication, threatens tap water and industrial or agricultural water water source, makes underground water forfeiture utility value, and organic pollutant enters food chain will directly threaten human health.
Along with the gradually attention of people to the landfill percolate problem, various leachate processing methods are developed widely.Leachate processing method commonly used generally comprises physico-chemical process, biochemical process and land law.
Physico-chemical process generally is that the qualified discharge and the biological treatment system of percolate effectively moves the good condition of creating as pre-treatment or advanced treatment.The influence that generally is not subjected to the leachate quality water yield is handled in materialization, and effluent quality is more stable, and especially to BOD/COD ratio lower (0.07~0.20), the percolate that is difficult to biochemical treatment has treatment effect preferably, when COD concentration is 2000~4000mgL
-1The time, the COD clearance of physico-chemical process generally can reach 50%~80%.But materialization treatment technology specific aim is too strong, and treatment effect is single, and the cost height, is unsuitable for the processing of a large amount of percolates.
Advantages such as biochemical process comprises aerobic treatment, anaerobic treatment and both in conjunction with the method for handling, and it has, and treatment effect is good, simple to operate, investment and running cost are low are suitable for handling biochemical percolate preferably.But biochemical process is difficult to remove the organic composition of those less relative molecular masses of having degraded, and its water outlet COD is difficult to be reduced to below the national standard.And its biochemical process the most serious defective in the process of handling percolate is that " always " age percolate less for BOD/COD ratio almost do not have treatment effect.
Land law is mainly removed suspended solids in the filtrate by the effects such as filtration, ion-exchange, absorption and precipitation of soil particle, and the solubilized composition is fixed on the particle.By the microorganism in the soil organism in the percolate and nitrogen are transformed simultaneously and stablize, reduce the amount of percolate by transpiration.The land law that is used for the percolate processing at present mainly contains the method for recharging and artificial swamp method.But the general floor space of land law is bigger.
The percolate water quality and quantity changes greatly, characteristics such as nutritive element is out of proportion, ammonia-nitrogen content cause its intractability greatly, realizes that it is focus and the difficult point that remains a research in the garbage loading embeading treatment technology that its economical and effective is handled.
Summary of the invention
Be to overcome above-mentioned the deficiencies in the prior art, it is low to provide a kind of cost to drop into order of the present invention, and treatment effect is good, simple to operate, operation and maintenance cost is low, is adapted to the various landfill percolate in age, and the garbage filter liquid processing method and the facility thereof of tool view repairing effect.
For addressing the above problem, the present invention by the following technical solutions:
The leachate processing method of a kind of circulated backfilling and artificial swamp coupling may further comprise the steps:
A. make percolate remove bigger suspended substance and the foreign material of part particle diameter through grille well;
B. the percolate with above-mentioned treated mistake concentrates on a part of grains of sand of removal and suspended substance in equalizing tank first lattice;
C. make that a part of percolate recharges to refuse landfill by the leachate recirculation system in above-mentioned equalizing tank first lattice, pour into artificial wet land system after the pre-treatment of another part through equalizing tank second lattice and equalizing tank the 3rd lattice and handle, water outlet back up to standard discharging.The total residence time of sewage in equalizing tank is 15~30 days.
Described percolate recharges to the concrete steps of refuse landfill by the leachate recirculation system: 1) with the leachate recirculation lift pump percolate in equalizing tank first lattice is promoted to the cloth water plant; 2) will in the percolate in the above-mentioned cloth water plant input inverted well and by the ditch that recharges of inverted well both sides it be recharged to refuse landfill by high density polyethylene(HDPE) (HDPE) pipe; 3) the leachate collection pipeline bottom landfill yard is concentrated to equalizing tank with the percolate of above-mentioned refuse landfill, and recharging frequency is 1~2 time/d, and recharging hydraulic load is 0.01~0.1m
3/ m
2.d.
The submerged type aerator carries out uninterrupted aeration, separate unit sphere of action 4~8m at the bottom of the described equalizing tank second lattice pond; The regular spoil disposal of sludge pump that is provided with at the bottom of the 3rd lattice pond, lift pump is delivered to percolate the distributing well of artificial wet land system at the bottom of the 3rd lattice pond.Described artificial wet land system unit hydraulic detention time 6~12 hours; When temperature on average is higher than 15 ℃, hydraulic load 10~15L/m
2.d; During 4~15 ℃ of temperature on average, hydraulic load 5~10L/m
2.d; When temperature on average is lower than 4 ℃ or when daily rainfall is 4~15mm, hydraulic load 3~5L/m
2.d; When daily rainfall during, stop into water greater than 15mm.
A kind of percolate treatment facility of realizing above-mentioned leachate processing method, comprise grille well, place grille well equalizing tank, circulated backfilling system and artificial wet land system afterwards, equalizing tank is become three lattice by function optimization, forms anoxic-aerobic-anoxybiotic functional mode.Establish one of rotary type grid in the grille well, the grille well water outlet directly links to each other with first lattice of equalizing tank.
The described equalizing tank first lattice useful volume is 60%~80% of the total useful volume of equalizing tank, second lattice are identical with the 3rd lattice useful volume, one of leachate recirculation lift pump is set in first lattice, 1~4 submerged type aerator is set at the bottom of the second lattice pond, one of sludge pump and lift pump is set at the bottom of the 3rd lattice pond.Inverted well that described circulated backfilling system comprises the cloth water plant successively, link to each other with the cloth water plant by the HDPE pipe and inverted well both sides recharge ditch.Every 40~50m inverted well is set, respectively designs one about inverted well and recharge ditch, recharge groove structure and be: the centre is the perforation water distributing pipe, fills graded broken stone all around, on cover one deck compacting clay seam.
Described artificial wet land system is divided into the artificial swamp unit of different shapes and area according to landform with it, connect according to actual needs between unit and the unit and in parallel, the artificial swamp element length is 20~50m, long: wide=1~3: 1, the distributing well water outlet links to each other with the unitary water distributor of artificial swamp, cover the thick polyethylene film of 0.1~0.5mm at the artificial swamp cell surface winter after wetland plant is withered, described wetland plant is an emergent.When the artificial swamp unit is positioned at the final tectum of landfill yard, directly utilize the final tectal place of landfill yard to make up the artificial swamp unit, more than waste layer, arrange respectively from bottom to top: clay seam, HDPE anti seepage membrane sealing ply, synthetic materials water conservancy diversion layer, fill stratum, vegetable layer, front end is provided with the perforation water distributor in the artificial swamp unit; When the artificial swamp unit is positioned at beyond the landfill zone, at first carry out smooth to ground, lay sandstone water conservancy diversion layer then, be equipped with the perforation thrust-augmenting nozzle in this layer, cover clay seam on the sandstone water conservancy diversion layer, smooth back covers HDPE anti seepage membrane sealing ply, is followed successively by sand stone layer, fill stratum and vegetable layer on the film, front end is provided with the perforation water distributor in the artificial swamp unit, and water distributor exceeds vegetable layer.
When described artificial swamp unit is positioned at the final tectum of landfill yard, thickness of clay soil is that 0.2~0.3m, HDPE anti seepage membrane sealing bed thickness 〉=1mm, synthetic materials water conservancy diversion layer thickness are 0.2~0.3m, fill stratum thickness 〉=0.3m, vegetable layer thickness 〉=0.3m, perforation water distribution pipe range 3~5m, water distributor exceeds vegetable layer 0.3~0.6m; When described artificial swamp unit is positioned at beyond the landfill zone, the smooth gradient in ground is 1%~2%, sandstone water conservancy diversion layer thickness is 0.2m, and interval 10m lays a perforation water distributor in the sandstone diameter≤1cm, sandstone water conservancy diversion layer, clay bed thickness 0.2m on the sandstone water conservancy diversion layer, HDPE anti seepage membrane sealing bed thickness 1mm, sandstone bed thickness 0.2m on the anti seepage membrane, fill stratum and vegetable layer thickness all are not less than 0.3m, the perforation water distributor is about 3~5m, and water distributor exceeds vegetable layer 0.3~0.6m.
The plant that described artificial swamp unit vegetable layer is planted is mainly emergents such as reed, hay grass, parasol bamboo, cattail, Canna generalis Bailey, bambusa textile grass, Scirpus tabernaemontani, Herba Cyperi Glomerati and Medulla Junci.Plantation kindred plant in the same unit, but different unit domestic demands is planted different plants according to the view needs with the sewage feature, and regularly plant is gathered in.
Advantage of the present invention is:
1. the present invention combines sewage disposal technology with the view recovery technique is organic, when the percolate processing is reached national grade one discharge standard (GB16889-1997), the view reparation has been carried out in refuse landfill.
2. the present invention has the effect that reduces the percolate quantity discharged, and leachate recirculation system and artificial wet land system can both be to hold back the total amount with the mode minimizing percolate by a relatively large margin of Evaporation.
3. equalizing tank of the present invention can carry out preliminary treatment through function optimization to percolate in the savings percolate, alleviated the load pressure of artificial wet land system.
4. the present invention is adapted to the percolate in any landfill age and handles, and along with the landfill yard growth of working life, the construction area of the artificial swamp that is obtained is also just big more, and the processing power of percolate also improves thereupon gradually.
5. implementation cost of the present invention is low, and especially landfill yard carries out subregion landfill and subregion when finally covering, and the structure of artificial swamp directly utilizes final tectal structure, only needs wetland unit is separated and increased corresponding water delivery and cloth drainage facility.
6. the present invention can quicken garbage decomposition, accelerates the waste stabilisation process, improves the product methane speed of rubbish and produces methane content.
7. the present invention does not only need the additional substance and the energy to carry out water quality regulation, and makes that moisture, nitrogen and organic substance in the percolate are utilized by plant, but is converted into the biomaterial with renewable resources.
Description of drawings
Fig. 1 is a process flow sheet of the present invention;
Fig. 2 is an equalizing tank synoptic diagram of the present invention;
Fig. 3 is a circulated backfilling system schematic of the present invention;
Fig. 4 is the ditch diagrammatic cross-section of recharging of the present invention;
Fig. 5 is the final tectal artificial swamp unit section synoptic diagram of landfill yard that is positioned at of the present invention;
Fig. 6 is the landfill yard zone artificial swamp unit section synoptic diagram in addition that is positioned at of the present invention.
Label declaration in the accompanying drawing is as follows:
1, equalizing tank first lattice 2, equalizing tank second lattice 3, equalizing tank the 3rd lattice
4, leachate recirculation lift pump 5, submerged type aerator 6, sludge pump
7, lift pump 8, grille well 9, leachate collection pipeline
10, inverted well 11, solid refuse 12, cloth water plant
13, compacting clay 14, graded broken stone 15, perforation water distributing pipe
16, perforation water distributor 17, vegetable layer 18, fill stratum
19, synthetic materials water conservancy diversion layer 20, HDPE anti seepage membrane sealing ply 21, clay seam
22, waste layer 23, rising pipe 24, sand stone layer
25, clay seam 26, sandstone water conservancy diversion layer 27, perforation thrust-augmenting nozzle on the sandstone water conservancy diversion layer
Embodiment
Embodiment of the invention technical process as shown in Figure 1.
Embodiment 1
Certain newly-built landfill yard, grille well 8 (as shown in Figure 3) is arranged at northwest corner, equalizing tank north side, is of a size of length * wide=2000mm * 700mm, available depth 1.95m.In establish 1 of rotary machine grid, effective grid width 0.7m, gas-distributing motor power 1.2kW, perforate 300mm * 300mm in the grille well south links to each other with equalizing tank.
As shown in Figure 2, equalizing tank useful volume 3600m
3, available depth 3m.Equalizing tank first lattice 1 size length * wide=36m * 25m, equalizing tank second lattice 2 and the 3rd lattice 3 sizes are length * wide=12m * 25m, and the equalizing tank total hrt is 20 days.5 two of submerged type aerators are set in second lattice carry out uninterrupted aeration, separate unit sphere of action 5m, gas-distributing motor power 3.7kW.6 one (flow 12.5m of sludge pump are set at the bottom of the 3rd lattice pond
3/ h, lift 9m, gas-distributing motor power 0.75kW), regular spoil disposal, and 7 one (flow 12.5m of lift pump are set
3/ h, lift 20m, gas-distributing motor power 2kW), percolate is delivered to the distributing well of artificial wet land system, the distributing well water outlet connects the unitary perforation water distributor 16 of artificial swamp (as shown in Figure 5).
Percolate in equalizing tank first lattice recharges to refuse landfill through the circulated backfilling system, as shown in Figure 3, the concrete approach that the circulated backfilling system realizes is: at first leachate recirculation lift pump 4 is promoted to cloth water plant 12 with the percolate in equalizing tank first lattice, the HDPE pipe is with in the input of the percolate in the cloth water plant inverted well 10 then, and by the ditch that recharges of inverted well both sides it is recharged to refuse landfill, the leachate collection pipeline 9 by the landfill yard bottom is concentrated to equalizing tank with the percolate of above-mentioned refuse landfill.Every 50m inverted well is set, respectively designs a 50m * 2m * 0.5m about inverted well and recharge ditch, its structure as shown in Figure 4, the centre is the perforation water distributing pipe 15 of Ф 100mm, fills graded broken stone 14 all around, on cover one deck compacting clay 13.Recharging frequency is 2 times/d, and recharging hydraulic load is 0.5m
3/ m
2.d.
Through circulated backfilling repeatedly, the Decomposition of the adsorption of soil and microorganism makes the gross contamination material concentration in the percolate reduce in the landfill yard, and recharges that the effect of damming of Evaporation and solid refuse 11 (as shown in Figure 3) reduces the volume of percolate significantly in the process.And the aeration of second and third lattice of equalizing tank and anaerobic process can make the Pollutant levels in the percolate further reduce.
The initial operating stage of present embodiment, not final covering place can be used, and therefore early stage artificial swamp unit is built in beyond the landfill yard zone.As shown in Figure 6, at first smooth (gradient is 2%) carried out on ground, lay the thick sandstone water conservancy diversion layer 26 of 0.2m then, interval 10m lays a perforation thrust-augmenting nozzle 27 to draw groundwater flow in the sandstone diameter≤1cm, this layer; Cover the thick clay seam of 0.2m 25 on the sandstone water conservancy diversion layer 26, smooth back covers the thick HDPE anti seepage membrane sealing ply 20 of 1mm.The sand stone layer 24 and the thickness that are followed successively by 0.2m thickness on the film all are not less than 0.3m fill stratum 18 and vegetable layer 17, are provided with rising pipe 23 in the sand stone layer 24.Be about the perforation water distributor 16 of 5m in the front end setting of artificial swamp unit, water distributor exceeds vegetable layer 0.5m.
Behind the present embodiment operation certain hour, part landfill zone finally covers gradually, directly utilize the final tectal place of landfill yard to make up the artificial swamp unit, as shown in Figure 5, arrange respectively from bottom to top more than 22 in waste layer: clay seam 21 (1m), HDPE anti seepage membrane sealing ply 20 (2mm), synthetic materials water conservancy diversion layer 19 (0.3m), fill stratum 18 (thickness 〉=0.3m) and vegetable layer 17 (thickness 〉=0.3m), be provided with rising pipe 23 in the synthetic materials water conservancy diversion layer 19.Be about the perforation water distributor 16 of 5m in the front end setting of artificial swamp unit, water distributor exceeds vegetable layer 0.5m.
Artificial swamp cell size length * wide=30m * 15m in the present embodiment, artificial swamp unit hydraulic detention time 6 hours, when temperature on average is higher than 15 ℃, hydraulic load 10L/m
2.d, during 4~15 ℃ of temperature on average, hydraulic load 5L/m
2.d, when temperature on average is lower than 4 ℃ or when daily rainfall is 4~15mm, hydraulic load 3L/m
2.d, when daily rainfall during, stop into water greater than 15mm.Cover the thick polyethylene film of 0.2mm at the artificial swamp cell surface winter after wetland plant is withered.
The plant that worker's wetland unit vegetable layer in the present embodiment is planted is mainly emergents such as reed, hay grass, Canna generalis Bailey, bambusa textile grass, Scirpus tabernaemontani and Medulla Junci.Plantation kindred plant in the same unit, but different unit domestic demands is planted different plants according to the view needs with the sewage feature, and regularly plant is gathered in.
Present embodiment artificial swamp final outflow water water-quality guideline reaches (GB16889-1997) first discharge standard of country's " household refuse landfill sites pollution control criterion ".
Embodiment 2
Certain refuse landfill, equalizing tank useful volume 3600m
3, it is of a size of length * wide=60m * 25m, available depth 3m.Former 4 sequencing batch activated sludge reactors (SBR) that have, preliminary treatment reach " household refuse landfill sites pollution control criterion " and (GB16889-1997) incorporate the municipal wastewater pipe network into after three grades of emission standards.Now relocate because of sewage network, the cost of incorporating city planting ductwork into is excessive, uses the back up to standard discharging of the present invention's individual curing in landfill yard.
Present embodiment at first carries out the function optimization transformation to equalizing tank, every being divided into three lattice, and makes it form anoxic-aerobic-anoxybiotic functional mode by increasing corresponding aerator it.First lattice size length * wide=36m * 25m, second and third lattice size of equalizing tank length * wide=12m * 25m.2 of submerged type aerators are set in second lattice carry out uninterrupted aeration, separate unit sphere of action 5m, gas-distributing motor power 3.7kW.1 (flow 12.5m of sludge pump is set at the bottom of the 3rd lattice pond
3/ h, lift 9m, gas-distributing motor power 0.75kW), regular spoil disposal, and 1 (flow 12.5m of lift pump is set
3/ h, lift 20m, gas-distributing motor power 2kW), percolate is delivered to the sbr reactor device.
Present embodiment is set up the leachate recirculation system in newly-built landfill district, and building mode and recycling mode are with embodiment 1.
The landfill yard area that present embodiment has finally covered is approximately 20000m
2, directly utilize the final tectal place of landfill yard to make up artificial swamp, building mode is with embodiment 1.The water outlet of sbr reactor device is as the water inlet of artificial wet land system.
Present embodiment artificial swamp final outflow water water-quality guideline reaches (GB16889-1997) first discharge standard of country's " household refuse landfill sites pollution control criterion ".