Summary of the invention
For the shortcoming of above-mentioned prior art, the invention provides danger that a kind for the treatment of effect better, do not produce secondary pollution and to give up the treatment process of percolate.
For achieving the above object, the technical solution used in the present invention is: a kind for the treatment of process of useless percolate of endangering, specifically comprises the following steps:
1. in the useless percolate of danger, add alkaline matter, stir, make pH value be 10 ~ 11;
2. in the material after step 1. middle alkali tune, add coagulating agent and flocculation agent, stir, make percolate produce flocculent precipitate, and layering, form mud mixture;
3. with mud and water separating equipment, mud-water separation is carried out to the mud mixture in 2., collect supernatant liquid and mud;
4. under normal temperature condition, when pH value is about 10 to the capable stripping of liquid in 3., until near below the 30mg/L of ammonia nitrogen value in liquid; With absorption liquid, stripping tail gas is reclaimed simultaneously;
5., under pH value is about 11 conditions, the material complete to 4. middle stripping carries out evaporation concentration, phlegma in line Sewage Plant adapter mouth;
6. to percolate evaporation concentration and 3. in sludge liquid be cured, cured body returns landfill yard landfill.
Preferably, described alkaline matter is lime powder.
Preferably, described coagulating agent is aluminium chlorohydroxide (PAC).
Preferably, described flocculation agent is polyacrylamide (PAM).
Preferably, described step 1. in the danger that uses give up percolate for the percolate of waste landfill site of endangering, wherein except containing except a large amount of ammonia nitrogen also containing more than a large amount of heavy metal ion, salinity, prussiate and height poison organism two class or two classes, and content is more than associated emissions limit value in GB8978-1996 " integrated wastewater discharge standard " grade III Standard and CJ 3082-1999 " sewage enters municipal sewage system water quality standard ", biodegradability extreme difference; The Hazardous wastes of landfill comprises industrial residue from industries such as petrochemical industry, plating, fine chemistry industry, incineration firing, pharmacy and waste material.
Preferably, described step 2. in the mass concentration of aluminium chlorohydroxide be: 5-10%, aluminium chlorohydroxide adds coagulating agent add-on in rear percolate and is: 30-50mg/L; The mass concentration of polyacrylamide is 0.1-0.5%, and polyacrylamide adds coagulating agent add-on in rear percolate and is: 1-10mg/L; Concrete needs test is determined.
Preferably, described step 3. in mud and water separating equipment can be plate-and-frame filter press, belt filter press, settling tank, run-off etc.
Preferably, described step 4. in the stripping equipment that adopts of stripping be the stripping tower, stripping pond etc. of device for absorbing tail gas.
Preferably, described step 4. in absorption liquid be mineral acid absorption liquid.
Preferably, described step 5. in evaporation concentration adopt evaporation equipment be all kinds of vaporizer; Evaporation concentration is to the 1/3-1/10 of original volume.
Preferably, described step 5. in phlegma meet the requirement of associated emissions limit value in GB8978-1996 " integrated wastewater discharge standard " grade III Standard and CJ 3082-1999 " sewage enters municipal sewage system water quality standard ".
Table 1 associated emissions limit value
Preferably, described step 6. in percolate evaporation concentration and 3. in the method that is cured of sludge liquid can adopt in Chinese patent CN104496139A (application number: CN201510000052.3), CN104475431A (application number: CN201510000055.7) and CN 104070052A (application number: CN201410296106.0) and have disclosed method.
The present invention has positive effect:
(1) the present invention is when processing the useless percolate of danger, ammonia nitrogen is separated from percolate, organism, heavy metal and salinity to be retained in concentrated solution and final solidify & bury had both made discharge of wastewater index reach requirement, also make each type organic not produce secondary pollution, environmental benefit is good.
(2) the present invention adopts the method for flocculation to carry out pre-treatment to percolate, reduces the concentration of heavy metal ion, organism and suspended particulate.
(3) first the present invention carries out stripping to the useless percolate of danger before evaporation concentration under pH value is 10-11 condition, which ensure that the non-volatile or few volatilization of organism and ammonia farthest removes, organism in tail gas is reduced to greatest extent and ammonia nitrogen qualified discharge in phlegma; When pH value is 11, evaporation concentration is carried out to percolate, it reduce organic content in phlegma.
(4) the present invention reclaims tail gas ammonia when carrying out stripping to the useless percolate of danger, has certain economic benefit.
(5) the inventive method is applicable to mostly endangering the process of waste landfill site percolate, and promoted extension is wide.
Present invention process achieves the minimizing of the useless percolate of danger, innoxious and resource utilization to greatest extent, process does not cause the loss of heavy metal ion, high malicious organism and salinity, not producing secondary pollution, do not cause load impact to subsequent disposal, is the good method of the useless percolate process of danger.
Embodiment:
As shown in Figure 1: a kind for the treatment of process of useless percolate of endangering, specifically comprises the following steps:
1. in the useless percolate of danger, add lime, stir, make pH value be 10 ~ 11;
2. in the material after step 1. middle alkali tune, add coagulating agent PAC and flocculation agent PAM, stir, make percolate produce flocculent precipitate, and layering;
3. with mud and water separating equipment, mud-water separation is carried out to mud mixture in 2., collect supernatant liquid and mud;
4., under normal temperature condition, when pH value is about 10, stripping is carried out, until near below the 30mg/L of ammonia nitrogen value in percolate to percolate in 3.; With absorption liquid, stripping tail gas is reclaimed simultaneously.
5., under pH value is about 11 conditions, the material complete to 4. middle stripping carries out evaporation concentration, phlegma in line Sewage Plant adapter mouth;
6. to percolate evaporation concentration and 3. in sludge liquid be cured, cured body returns landfill yard landfill.
Embodiment 1
The present embodiment process be certain danger waste landfill site percolate, the useless mainly surface of landfill danger is containing the electroplating sludge of a large amount of grease, wherein pH is 7.86, COD concentration is 21983mg/L, ammonia nitrogen concentration is 2341mg/L, in heavy metal index, copper content is 342mg/L, and nickel content is 152mg/L, and other indexs reach the requirement of associated emissions limit value in GB8978-1996 " integrated wastewater discharge standard " grade III Standard and CJ 3082-1999 " sewage enters municipal sewage system water quality standard ".
The danger of the present embodiment leachate processing method that gives up comprises the following steps:
1. in 2L percolate, add 40g lime powder, stir, pH value is 10.85;
2. in the material after step 1. middle alkali tune, add the coagulating agent PAC2ml that concentration is 5%, PAC adds coagulating agent add-on in rear percolate and is: 50mg/L; Add the flocculation agent PAM 4ml of concentration 0.5%, PAM adds coagulating agent add-on in rear percolate and is: 10mg/L, stirs, and after leaving standstill 15min, percolate layering is good;
3. by Büchner funnel simulation water extracter, mud-water separation is carried out to mud mixture in 2., collect supernatant liquid and mud;
4., under normal temperature condition, adopt pneumatic pump and aeration head and self-control stripping bottle simulation stripping pond to carry out stripping experiment, control ph is about 10, and when stripping time is 18min, in percolate, ammonia nitrogen value is 23mg/L; Be that the sulfuric acid of 1mol/L reclaims stripping tail gas as absorption liquid by 50ml concentration, until saturated after re-absorption effect, in absorption liquid, COD concentration is 136mg/L, cleaner simultaneously.Using absorption liquid as landfill yard vegetation ammonia Fertilizer application, respond well.
5., when pH value is 11, the material adopting electric furnace and large flask to simulate vaporizer complete to 4. middle stripping carries out evaporation concentration, analyzes index of correlation content in phlegma; Experiment finds when concentrated leachate volume is 415ml, a large amount of solid sediment is all there is in bottle, to be heated at the bottom of causing bottle inequality, " bumping " phenomenon occurred, although now appoint in bottle and have a small amount of liquid, but cannot carry out evaporation concentration operation, now concentrated solution volume is 21% of percolate, and evaporation time is about 70min.
Analysis phlegma finds, its pH value is 10.8, and ammonia-nitrogen content is 5mg/L, COD content is 214mg/L, and heavy metal does not detect, and all meets emission request, can directly discharge.
6. get evaporation concentration liquid and flocculation sludge 0.5kg altogether, add sodium sulfide solution 20ml, stir; Add white lime powder 100g again, Keep agitation is even; Then slowly add gesso 450g, be stirred to material shape glomeration particulate matter; Above-mentioned material seasoning is solidified 1 day, gets bisphenol A-type (trade mark E-44) epoxy resin 40mL and mix with globular material, make the even coated material of epoxy resin; Add epoxy curing agent 10mL subsequently, now material becomes sticky immediately; Material is put in the cement specimen mold of length of side 0.15m, after the demoulding, cured body is placed 2-3 angel particle outer layer ring epoxy resins completion of cure.
Analyze cured body Leaching, find to meet the requirements completely, cured body can direct landfill.
Embodiment 2
The present embodiment process be another danger waste landfill site percolate, landfill danger useless mainly arsenic slag, flying ash and chemical industry rectification residue, wherein pH is 8,76, COD concentration is 11452mg/L, and ammonia nitrogen concentration is 1385mg/L, and in heavy metal index, arsenic content is 12mg/L, cadmium content is 3mg/L, and other indexs reach the requirement of associated emissions limit value in GB8978-1996 " integrated wastewater discharge standard " grade III Standard and CJ 3082-1999 " sewage enters municipal sewage system water quality standard ".
The danger of the present embodiment leachate processing method that gives up is identical with embodiment 1, and difference is:
1. step adds lime powder 20g, and after stirring, pH value is 10.54;
Step is 4. when stripping time is 14min, and in percolate, ammonia nitrogen value is 18mg/L; In absorption liquid, COD concentration is 152mg/L.
5. step stops concentrated when concentrated leachate volume is 500ml, now concentrated solution volume is 27% of percolate, and evaporation time is about 60min.
Analysis phlegma finds, its pH value is 10.5, and ammonia-nitrogen content is 3mg/L, COD content is 265mg/L, and heavy metal does not detect, and all meets emission request, can directly discharge.
Carry out Leaching to the cured body of mud and evaporation concentration liquid to analyze, find to meet the requirements completely, cured body can direct landfill.
Embodiment 3
The present embodiment process be waste landfill site another batch of percolate of endangering in embodiment 1, landfill danger useless mainly electroplating sludge, agricultural chemicals refuse, phosphatization slag etc., wherein pH is 9.41, COD concentration is 13651mg/L, ammonia nitrogen concentration is 1689mg/L, in heavy metal index, Zn content is 113mg/L, copper content is 94mg/L, and other indexs reach the requirement of associated emissions limit value in GB8978-1996 " integrated wastewater discharge standard " grade III Standard and CJ 3082-1999 " sewage enters municipal sewage system water quality standard ".
The danger of the present embodiment leachate processing method that gives up is identical with embodiment 1, and difference is:
1. step adds lime powder 10g, and after stirring, pH value is 9.93;
Step is 4. when stripping time is 15min, and in percolate, ammonia nitrogen value is 22mg/L; In absorption liquid, COD concentration is 191mg/L.
5. step stops concentrated when concentrated leachate volume is 360ml, now concentrated solution volume is 18% of percolate, and evaporation time is about 85min.
Analysis phlegma finds, its pH value is 10.6, and ammonia-nitrogen content is 4mg/L, COD content is 315mg/L, and heavy metal does not detect, and all meets emission request, can directly discharge.
Carry out Leaching to the cured body of mud and evaporation concentration liquid to analyze, find to meet the requirements completely, cured body can direct landfill.