CN102491574B - Advanced treatment technology for comprehensive wastewater of iron and steel enterprises - Google Patents
Advanced treatment technology for comprehensive wastewater of iron and steel enterprises Download PDFInfo
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- CN102491574B CN102491574B CN 201110446236 CN201110446236A CN102491574B CN 102491574 B CN102491574 B CN 102491574B CN 201110446236 CN201110446236 CN 201110446236 CN 201110446236 A CN201110446236 A CN 201110446236A CN 102491574 B CN102491574 B CN 102491574B
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Abstract
The invention discloses an advanced treatment technology for comprehensive wastewater of iron and steel enterprises, and solves the problems of easy reverse osmosis membrane pollution by organic substances, easy obstruction, difficult cleaning and the like common in existing ultrafiltration and reverse osmosis double-membrane combined technology. The technology first conducts pretreatment to reused wastewater, then carries out subsequent ultrafiltration and reverse osmosis treatments, and finally discharges the wastewater. In the pretreatment process, the wastewater is delivered to a multi-medium filter through a pipeline for filtering so as to reduce the turbidity and oil content of the wastewater. The technology of the invention has the advantages of simple process, simple and convenient operation, stable system, long membrane cleaning cycle, as well as low investment and operation cost.
Description
Technical field
The present invention relates to a kind of waste water treatment process, a kind of specifically iron and steel enterprise comprehensive wastewater advanced treatment process.
Background technology
Because there are continuous casting, hot rolling, cold rolling supervisor unit in iron and steel enterprise, discharging blended waste water via said units, to have a variation water quality big, contain characteristics such as micro oil and dissolved solids content height, reuse waste water oil-contg is still at 0.8-4mg/L through emission treatment (handling through physico-chemical process) for iron and steel enterprise's comprehensive wastewater, and COD is at 15-40mg/L.Desalting treatment for this class waste water, domestic iron and steel enterprises has the case history of the two film couplings of employing " ultrafiltration+reverse osmosis ", but operating performance from actual Engineering Projects, because handling oily(waste)water, enterprise lacks experience, waste water there is not preprocessing process, therefore the ubiquity reverse osmosis membrane occurs Organic pollutants easily, easily stops up and clean problem such as difficulty, and major cause is that waste water contains micro oil and COD.Fall turbid effect preferably though ultrafiltration has,, micro oil and COD are held back weak effect, can not satisfy of the requirement of RO film indexs such as water inlet oleaginousness, COD because of membrane pore size is bigger.In addition, enterprise is generally the reduction construction investment, selected RO membrane flux is higher, thereby has further increased the weight of the severity that film pollutes, and quickens The decline of membrane flux, the film cleaning interval is shortened gradually, clean frequent (about 15-30 days), and then cause the reverse osmosis desalination rate to descend, membrane module shortening in work-ing life, production and running cost significantly increase, and influence operation down normally moves.Therefore must carry out pre-treatment before to reduce its oil-contg in " ultrafiltration+reverse osmosis ", rationally choose the membrane process controlled variable simultaneously.Popular reverse osmosis pretreatment technology is mainly turbid to fall at present, does not consider oil-contg and the COD index disadvantageous effect to reverse osmosis membrane, and existing problems are a lot.
Summary of the invention
To the present invention seeks in order solving the problems of the technologies described above, to provide that a kind of technology is simple, easy and simple to handle, system stability, film cleaning interval are long, investment and the low iron and steel enterprise's comprehensive wastewater advanced treatment process of running cost.
Iron and steel enterprise of the present invention comprehensive wastewater advanced treatment process is: reuse waste water is carried out pre-treatment earlier, and then carry out water outlet after follow-up ultrafiltration and the reverse-osmosis treated, described pretreatment technology filters to reduce oil-contg and turbidity in the water for waste water is sent into more medium filter through pipeline, wherein, the filtering velocity of described reuse waste water in more medium filter is 8-10m/h, described more medium filter comprises the filtrate district on water distributing area, bearing area, middle part and the top of bottom, described bearing area filler is a Φ 3-5mm gravel, and filling thickness is 200-300mm; Described filtrate district is made of the coarse filtration floor on upper strata and the fine filtering floor of lower floor, described coarse filtration layer filler is hard coal, at least a in make pottery filter and the activated carbon, particle size range is 1.6-3.0mm, filling thickness 400-600mm, described fine filtering layer filler is quartz sand, its particle size range is 0.5-1.2m, and filling thickness is 600-800mm.
Add the 4-5mg/L flocculation agent in the reuse waste water before entering more medium filter and carry out little flocculation.
When oil-contg is less than 1.0mg/L in the described reuse waste water, do not add flocculation agent; When described reuse waste water oil-contg meets or exceeds 1.0mg/L, add the 4-5mg/L flocculation agent in the reuse waste water before entering more medium filter.
Described fine filtering layer is made of the quartz sand layer of two-layer different-grain diameter, and every layer of 300-400mm is thick, and the upper strata particle diameter is 0.5-0.8mm, and lower floor's particle diameter is 0.8-1.2mm.
Described more medium filter is carried out regular backwash, and described backwash process is followed successively by air purge, gas-vapor mix is washed, washed, and wherein, washing intensity is 8-10m
3/ m
2.h, air purge pressure 0.07MPa.
The air purge time is 3-5min in the described backwash process, and the gas-vapor mix time of washing is 8-10min, and the washing time is 8-10min.
Film design flux is 40-43L/m2.h in the described ultrafiltration step, and reverse osmosis step comprises one-level infiltration and secondary infiltration, and described one-level permeable membrane design flux is 17-20L/m
2.h, secondary permeable membrane design flux is 30-35L/m
2.h.
Reuse waste water of the present invention (being the waste water of iron and steel enterprise's comprehensive wastewater after emission treatment) water quality different fully with common sanitary sewage (oil-containing and COD height), and because the pretreatment technology step of design is fairly simple again, therefore the applicant furthers investigate the filtrate district in the more medium filter, above quartz sand layer, set up the coarse filtration layer, described coarse filtration layer filler can use hard coal, a kind of in filter and the activated carbon makes pottery, and particle diameter should be greater than the fine filtering layer of quartz sand, the filler of these coarse filtration layers is a porous medium, specific surface area is big, the sorptive power height, to oil and COD advantages of good adsorption effect, filtration resistance is little.Further, the contriver is controlled at 0.5-1.2mm with the size range of quartz sand, and the quartz sand sorptive power of small particle size is low, but hole is little between the grains of sand, and sieving is made good use of, and helps reducing turbidity and emulsification shape oil, can well cooperate with the coarse filtration layer.Further research experiment proves, the fine filtering layer is constituted by the quartz sand layer of two-layer different-grain diameter, the upper strata particle diameter is 0.5-0.8mm, lower floor's particle diameter is 0.8-1.2mm, by the quartz sand layer of different gradation, can well hold back oil and other material in the waste water, it is the most satisfied that turbid effect falls in oil removing, the thickness of controlling each layer has simultaneously also reduced the height of tank body when guaranteeing filter effect, reduced the investment of equipment.In addition, because oil is outstanding turbid state in water, reuse waste water can bring very big influence to its deoiling effect by the filtering velocity of more medium filter, and filtering velocity is too fast, and then the quartz sand deoiling effect sharply descends; Filtering velocity is slow excessively, and then the coarse media deoiling effect is poor, and quartz sand filter media hardens soon the backwash weak effect; Therefore must the control filtering velocity at 8-10m/h, be preferably 10m/h especially, under this filtering velocity, work, cooperate the coarse filtration layer that adds effectively to improve and filter its oil removing, COD and turbidity effect, alleviate the strainer problem that hardens.
Described flocculation agent can use for example PAC (polymerize aluminum chloride) and/or PFS (bodied ferric sulfate) etc., when micro oil is lower than 1.0mg/L in the waste water, can not add flocculation agent, a spot of oil molecule can be adsorbed on the porous filter-material, colloidalmaterial and suspended impurity are stopped by quartz sand, and the oil-contg of sand filtration water outlet, COD and turbidity promptly can be controlled in the claimed range; When oil-contg in the waste water when meeting or exceeding 1.0mg/L, can add small amount of flocculant, can reach elimination of colloid stability effect preferably through the pipe-line blending before entering more medium filter, when filtering through more medium filter again, effectively the effect of stable filter oil removing prevents that filtrate from hardening.Simultaneously, the applicant also improves the regular backwash process of strainer, and the past backwash is single form, as only being washing, or only be air purge, or only wash for gas-vapor mix, now change into: advanced promoting the circulation of qi is washed, carrying out gas-vapor mix again washes, wash at last, and designed corresponding washing intensity and air purge pressure, and further the washing time is controlled according to filling out granulosa number and granularity, improve the backwash effect greatly, avoided running material.After pre-treatment, turbidity and oil-contg all can descend more than 50% in the waste water, and filter backwash is effective, and long-time running does not have filtrate and hardens and backwash race material phenomenon.
Outside the oil-contg, the contriver also adjusts the membrane flux parameter of subsequent ultrafiltration and reverse osmosis process, significantly reduces the saturating permeable membrane flux of ultra-filtration membrane and first order reaction, suitably improves the membrane flux of two-pass reverse osmosis in the cooperation pretreatment technology reduction waste water.Organism and oily substance have a strong impact on the organic membrane performance, and the lighter causes film dirty stifled, and be heavy then make its inefficacy; Waste water can make oil-contg descend, but still can not thoroughly remove through after the pre-treatment, still can cause dirty blocking up to ultra-filtration membrane and first-stage reverse osmosis film, makes its flux be subjected to certain limitation.But the water inlet of two-pass reverse osmosis film is after the first-stage reverse osmosis film is handled, and oleaginousness and saltiness all descend significantly, thereby membrane flux can fully obtain performance.Above-mentioned measure of control can guarantee system's operation steady in a long-term, find an optimal balance point handling between the water yield and investment, the running cost, avoid excessively pursuing membrane flux and cause problems such as poor, frequent matting of system stability or the shortening of film tube lifetime, prevent from frequently to spend the generation that huge fund is changed problems such as assembly.
Beneficial effect:
Technology of the present invention is very simple, easy and simple to handle, running cost is low, secondary de-mineralized water comprehensive cost is 2.09 yuan/ton, can effectively reduce every index in the water by pretreatment technology, oil-contg is less than 0.8mg/l, COD content satisfies the water inlet requirement of ultrafiltration technology step fully less than 20mg/l, can effectively improve the product water flux of ultra-filtration membrane, and the ultra-filtration membrane flux of avoiding oil pollution to cause is decayed fast; After the water outlet of ultrafiltration simultaneously, oil-contg further reduces, oil-contg is less than 0.5mg/l, but the matting cycle of significant prolongation reverse osmosis membrane (more than 1 year), improve the work-ing life of membrane module, can directly reduce the reuse cost of waste water advanced processing, the every index of water outlet is qualified, satisfies the reuse water standard.
Figure of description
Fig. 1 is a more medium filter structural representation of the present invention;
Fig. 2 filtering velocity influences (adding PAC) to single filtering material filter deoiling effect;
Fig. 3 filtering velocity influences (adding PFS) to single filtering material filter deoiling effect;
Fig. 4 filtering velocity is to more medium filter deoiling effect influence (adding PAC);
The little flocculation of Fig. 5 is to the influence of ultra-filtration membrane transmembrane pressure.
Wherein, 1-tank body 1,2-water distributing area, 3-bearing area, 4-fine filtering layer, 4.1-upper strata fine filtering layer, 4.2-lower floor fine filtering layer, 5-coarse filtration layer, 6-filtered water inlet mouth, 7-filter out the mouth of a river, 8-backwash water-in, 9-backwash water outlet, 10-backwash inlet mouth, 11-evacuation port, 12-population, 13-venting port.
Embodiment
Iron and steel enterprise's comprehensive wastewater with Wuhan Iron ﹠ Steel (Group) Corp. is that example further specifies technology of the present invention.
The structure of more medium filter is with reference to Fig. 1; more medium filter mainly comprises the water distributing area 2 that is positioned at tank body 1 bottom, the bearing area 3 at middle part and the filtrate district on top; bearing area 3 adopts gravel to fill; the filtrate district is made of coarse filtration floor 5 and fine filtering floor 4; the coarse filtration layer is any in hard coal, haydite or the activated carbon; (present embodiment adopts natural extra large sand to fine filtering layer 4 for quartz sand; quartz sand than hand breaking is more suitable for using as filtering layer); particle diameter adopts layering grating layout (shown in the figure to be two layers; from down being followed successively by 4.1,4.2, specifically particle diameter sees Table 1 by last).Filtered water inlet mouth 6 on the described tank body 1 and backwash water outlet 9 are communicated with 4 tops, filter grain district at tank body 1 top through pipeline, and the filter out mouth of a river 7, backwash water-in 8 and backwash inlet mouth 10 on the described tank body 1 are communicated with water distributing area 2 belows of tank body 1 bottom.Tank body 1 top also is provided with venting port 13, the bottom is provided with evacuation port 11, also is provided with population 12 on the tank body 1 as required.
The embodiment 1-3 of processing method:
Reuse waste water is sent into the filtrate district top of tank body 1 by filtered water inlet mouth 6 through pipeline by pressure pipeline (judge do not add or add flocculation agent and carry out little flocculation according to the oil-contg index of reuse waste water in the pipeline), filter oil removing layer by layer via coarse filtration layer 5, upper strata fine filtering layer 4.1, lower floor's fine filtering layer 4.2, bearing area 3 again and go turbid after flow out by the mouth of a river 7 that filters out of the below of water distributing area 2; Reuse waste water carries out ultrafiltration and reverse-osmosis treated again after more medium filter filters pre-treatment.In addition, more medium filter needs every operation 24h to carry out once gas, water backwashing under the regular situation, and backwash process is: 3-5min is washed in advanced promoting the circulation of qi, carries out gas-vapor mix then and washes 8-10min, washes 8-10min at last, and washing intensity is 8-10m
3/ m
2.h, air purge pressure 0.07MPa, the back flushing water yield equates with the filtration water yield.Those skilled in the art can rationally adjust concrete backwashing period, (each parameter sees table 1 and table 2 for details) according to water outlet requirement and water examination result.
Adopt the method for embodiment 1-3, system stable operation is more than 1 year, and strainer does not have and hardens and runs and expect phenomenon, and the RO membrane module does not carry out matting, and the water yield, water quality all reach design objective, also change.
Comparative example:
Comparative example is not thrown flocculation agent in reuse waste water, and after adopting individual layer quartz sand filter media strainer that reuse waste water is carried out pre-treatment, advances ultrafiltration and reverse-osmosis treated again, and determine ultrafiltration and reverse osmosis membrane flux with reference to surface water.Concrete parameter sees table 1 and table 2 for details.Adopt the method for comparative example, the strainer problem that hardens is outstanding, the water production rate deficiency, and the reverse osmosis membrane pollution level is serious, and membrane flux is decayed rapidly, and transmembrane pressure raises fast, finally causes and can't normally move because of the frequent matting of reverse osmosis membrane (15 days are once).
Table 1: embodiment 1-3 processing parameter tabulation
Table 2: each case actual operation parameters is (when moving 1 year) relatively
The deoiling effect comparative experiments:
Filter the little flocculation pretreatment technology of employing under the filtering velocity in difference, relatively quartz sand, haydite list medium filter and " haydite, hard coal, activated carbon+quartz sand " more medium filter are to the removal effect of oil, adopt filter column test device to test, it the results are shown in Figure shown in the 2-4.
From Fig. 2-4 as can be seen, filtering velocity all has a significant effect to the deoiling effect of single medium and more medium filter, but filtering velocity is in the 8-10m/h scope, and the more medium filter deoiling effect is more stable.
For many medium filter direct filtration and the deoiling effect of micro flocculating filter and the transmembrane pressure changing conditions of ultra-filtration membrane, adopt the simulation pilot plant to test, test-results sees Table 3 and Fig. 5.
The little flocculation of table 3 is to the influence (adding PAC) of more medium filter deoiling effect
From table 3 and Fig. 5 as can be seen, the relative direct filtration of micro flocculating filter, the water outlet oil-contg is low, can obviously reduce the transmembrane pressure of ultra-filtration membrane.Because of the pilot scale time shorter, can only find trend, in actual motion, both difference on effect are more obvious than pilot scale.
Claims (5)
1. iron and steel enterprise's comprehensive wastewater advanced treatment process, it is characterized in that, reuse waste water is carried out pre-treatment earlier, and then carry out water outlet after follow-up ultrafiltration and the reverse-osmosis treated, described pretreatment technology filters to reduce oil-contg and turbidity in the water for waste water is sent into more medium filter through pipeline, wherein, the filtering velocity of described reuse waste water in more medium filter is 8-10m/h, described more medium filter comprises the water distributing area of bottom, the filtrate district on bearing area, middle part and top, described bearing area filler is a Ф 3-5mm gravel, and filling thickness is 200-300mm; Described filtrate district is made of the coarse filtration floor on upper strata and the fine filtering floor of lower floor, described coarse filtration layer filler is hard coal, at least a in make pottery filter and the activated carbon, particle size range is 1.6-3.0mm, filling thickness 400-600mm, described fine filtering layer filler is quartz sand, its particle size range is 0.5-1.2m, and filling thickness is 600-800mm, does not add flocculation agent when oil-contg is less than 1.0mg/L in the described reuse waste water; When described reuse waste water oil-contg meets or exceeds 1.0mg/L, add the 4-5mg/L flocculation agent in the reuse waste water before entering more medium filter.
2. iron and steel enterprise as claimed in claim 1 comprehensive wastewater advanced treatment process is characterized in that described fine filtering layer is made of the quartz sand layer of two-layer different-grain diameter, and every layer of 300-400mm is thick, and the upper strata particle diameter is 0.5-0.8mm, and lower floor's particle diameter is 0.8-1.2mm.
3. iron and steel enterprise as claimed in claim 1 comprehensive wastewater advanced treatment process is characterized in that, described more medium filter is carried out regular backwash, and described backwash process is followed successively by air purge, gas-vapor mix is washed, washed, and wherein, washing intensity is 8-10m
3/ m
2.h, air purge pressure 0.07MPa.
4. iron and steel enterprise as claimed in claim 3 comprehensive wastewater advanced treatment process is characterized in that, the air purge time is 3-5min in the described backwash process, and the gas-vapor mix time of washing is 8-10min, and the washing time is 8-10min.
5. iron and steel enterprise as claimed in claim 1 comprehensive wastewater advanced treatment process is characterized in that, film design flux is 40-43L/m in the described ultrafiltration step
2.h, reverse osmosis step comprises one-level infiltration and secondary infiltration, and described one-level permeable membrane design flux is 17-20L/m
2.h, secondary permeable membrane design flux is 30-35L/m
2.h.
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| CN104176845B (en) * | 2013-05-20 | 2015-12-09 | 宝山钢铁股份有限公司 | A kind of process for reclaiming of cold rolling alkaline oily(waste)water |
| CN107540107B (en) * | 2016-06-29 | 2021-08-10 | 中国石油化工股份有限公司 | Deep oil-removing purification method for steam stripping purified water of oil refining |
| CN107694167B (en) * | 2017-10-31 | 2020-08-18 | 尚川（北京）水务有限公司 | Water collector for sand filter and sand filter |
| CN110342672A (en) * | 2018-04-04 | 2019-10-18 | 中国石油天然气集团有限公司 | Purify the processing system and its processing method of recovered water |
| CN108751488A (en) * | 2018-05-23 | 2018-11-06 | 台州创投环保科技有限公司 | A kind of large-scale wastewater treatment plant centrifugal type process for purifying water |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201313858Y (en) * | 2008-11-23 | 2009-09-23 | 陈业钢 | Steel wastewater zero-drainage regeneration combining device |
| CN101607768A (en) * | 2009-01-13 | 2009-12-23 | 陈业钢 | A kind of steel wastewater regenerating and recycling combined process |
| CN102030437A (en) * | 2010-11-04 | 2011-04-27 | 河北省首钢迁安钢铁有限责任公司 | Method for comprehensive wastewater desalination and zero release in steel production |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201313858Y (en) * | 2008-11-23 | 2009-09-23 | 陈业钢 | Steel wastewater zero-drainage regeneration combining device |
| CN101607768A (en) * | 2009-01-13 | 2009-12-23 | 陈业钢 | A kind of steel wastewater regenerating and recycling combined process |
| CN102030437A (en) * | 2010-11-04 | 2011-04-27 | 河北省首钢迁安钢铁有限责任公司 | Method for comprehensive wastewater desalination and zero release in steel production |
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