Papermaking deep based on chemical decalcification is processed wastewater recycling device
Technical field
The present invention relates to a kind of papermaking deep and process the treatment unit of waste water, particularly relate to a kind of reclamation set of the processing of the papermaking deep based on chemical decalcification technology, electrochemical techniques and membrane technique waste water.
Background technology
Paper-making effluent refers to the cooking waste liquor (claiming again black liquor, red liquid) that chemical pulping produces, the plain boiled water producing in the middle section water producing in pulp washing bleaching process and copy paper operation.General every production 1t sulfate pulp just has 1t organism and 400kg bases, sulfide to be dissolved in black liquor; Producing 1t sulfite pulp approximately has 900kg organism and 200kg oxide compound (calcium, magnesium etc.) to be dissolved in red liquid with sulfide.Waste liquid enters in rivers not only severe contamination water source, and causes a large amount of wastings of resources.Paper-making industry is traditional water rich and influential family, is also one of important source of pollution that cause water pollution.At present, the first place of China's paper-making industrial waste water quantity discharged and COD quantity discharged Jun Ju China all types of industries quantity discharged, paper industry is the most serious to the pollution of water surrounding, it is the matter of utmost importance of China's industrial pollution caused by paper manufacturing control still not, is also the matter of utmost importance that national trade effluent carries out processing up to standard and water saving.According to statistics, the above papermaking in county of China and county and paper products industry wastewater discharge account for 18.6% of national industrial total release, wherein process emission compliance amount and account for 49.3% of paper-making industrial waste water total release, in waste discharge, COD accounts for 44.0% of national industrial COD total release.Therefore, how eliminating that paper waste pollutes and make precious resources in waste liquid obtain utilizing is a job with great social effect and economic worth, should attach great importance to.Along with expanding economy, China faces the problem of shortage of fresh water, scarcity of raw material day by day, and on the other hand, water pollutes also more and more serious.In recent years, through unremitting effort in many ways, paper industry water prevention and cure of pollution have obtained certain achievement, although paper and paperboard production increase year by year, but reduced year by year of the COD in waste discharge.But the waste water that at present paper industry accounts for total emission volumn 50% not yet carries out processing up to standard, paper waste process after recycling few especially, therefore, paper waste prevention and cure of pollution and to recycle task also quite heavy.
Paper waste complicated component, biodegradability is poor, belongs to more unmanageable trade effluent, and its source and feature are:
1, cooking section waste liquid
Be the black liquor of alkaline process generation and the red liquid that acid polishing produces.Overwhelming majority paper mill adopts alkaline process and produces black liquor.In black liquor, contained pollutent has accounted for the more than 90% of industrial pollution caused by paper manufacturing total emission volumn, and has the characteristic of high density and difficult degradation, and its improvement is a great problem always.Main component in black liquor has 3 kinds, i.e. xylogen, poly-pentose and total alkali.Xylogen is the nontoxic natural high molecular substance of a class, has been widely used as industrial chemicals tool, and poly-pentose can be used as animal feed.
2, middle section water
Effluent refers to the waste water that the boiling slurry after black liquid extraction is discharged in the processes such as screening, washing, bleaching, and color is deep yellow, accounts for 8%~9% of industrial pollution caused by paper manufacturing total emission volumn, ton slurry COD load 310kg left and right.Middle section water concentration is higher than sanitary sewage, and the ratio of BOD and COD is between 0.20 to 0.35, and biodegradability is poor, and organism is difficult to biological degradation and intractability is large.Organism in middle section water is mainly xylogen, Mierocrystalline cellulose, organic acid etc., taking solubility COD as main.Wherein, what environmental pollution was the most serious is the chlorine-contained wastewater producing in bleaching process, such as Chlorinated Bleaching waste water, hypo(chlorite)bleaching waste water etc.Hypo(chlorite)bleaching waste water mainly, containing trichloromethane, also contains other organic chlorides of kind more than 40, wherein taking various chlorinated phenols as at most, as dichloro-phenol, three chlorinated phenols etc.In addition, in bleaching waste liquor, containing toxic extremely strong carcinogenic substance Dioxins, ecotope and HUMAN HEALTH have been caused to serious threat.
3, plain boiled water
Plain boiled water is copy paper workshop section waste water, and it derives from paper machine room paper making process.Plain boiled water mainly contains fiber fines, filler, coating and lysed timber composition, and the sizing material, Wet Strength Resin, sanitas that add etc., and taking insoluble COD as main, biodegradability is lower, and its sanitas adding has certain toxicity.The plain boiled water water yield is larger, but its contained organic pollution load is well below black digestion liquid and middle-stage wastewater.Nearly all paper mill paper machine room has all adopted part or totally-enclosed system to reduce papermaking water loss now, saves power consumption, improves plain boiled water reclamation rate, reduces unnecessary plain boiled water discharge.
At present, mainly contain for the method for paper waste processing: physical filtering method, coagulant sedimentation, absorption method, advanced oxidation processes, By Bubble-floating Method, acid adding absorption process, catalytic oxidation, biochemical process etc., every kind of method all has relative merits separately.Because single treatment process is difficult to be effective, in practice, normally according to the practical situation that will process waste water, several method is combined with, typical production technique be by paper waste through physical treatment such as filtrations grade, then qualified discharge after biochemical treatment again after flocculation sediment.
Chinese patent CN101708927A discloses a kind of advanced treatment method for papermaking waste water little, oxidative degradation+flocculation sediment+sand filtration that technique is simple, pollutants removal rate is high, working cost is cheap of investing.COD < 70mg/L after the method is processed, BOD5 < 20mg/L, SS < 30mg/L.
Ecological Disposal and resource recycling that Chinese patent CN1420091 discloses a kind of paper waste utilize method, and it is to utilize ecological engineering technology, and paper mill wastewater carries out BOD in settling tank
5: COD
crratio adjustment, then enter the digestion of series connection anaerobic pond and facultative lagoon, COD is carried out in draining in equalizing tank
cr: N: after P ratio is adjusted, be distributed into many groups rainwash wetland in parallel by transmission & distribution water system, water outlet is better than the primary standard of paper industry Sewage Water Emissions, can stay through the storage of the aerobic pool, supplement the required clear water of equalizing tank, is back to rainwash wetland and carries out the degree of depth and process.The method has overcome paper waste trophic structure imbalance, the poor shortcoming of biodegradability, can stablize the Ecological Disposal and the resource recycling utilization that effectively realize paper waste.
Chinese patent CN101337752 discloses a kind of advanced treatment process for paper-making waste water, this technique comprises the following steps: the paper waste after secondary biochemical treatment is introduced to micro-aeration iron reduction bed, in micro-aeration iron reduction bed, load iron filings, paper waste carries out reduction reaction in micro-aeration iron reduction bed; By step 1. water outlet after treatment introduce in coagulation basin, in coagulation basin, add coagulating agent and coagulant aids, impel the particle aggregation in water; 2. step is carried out to mud-water separation in water outlet introducing settling tank after treatment; The water outlet of settling tank is introduced in filtering basin and filtered, and the water outlet after filtration, after sterilization and disinfection, is introduced reuse water pipe network; Sewage backwash water in mud in settling tank and filtering basin is introduced to sludge thickener, and after dehydration, outward transport is disposed; Meanwhile, the overflowing liquid in dehydration filtrate and sludge thickener is introduced in coagulation basin and is processed.This invented technology is simple, good decolorizing effect and with low cost.
Above method all obtains reasonable effect to the processing of paper waste, but all exist the processing degree of depth inadequate, the middle water of producing also contains more pollutent, can only be applicable to some production technique not high to water specification of quality, and its purposes consumption is all restricted.Make paper waste regeneration, meet the water requirement of various processes, the particularly requirement of high quality water, must carry out deep purifying processing to it, as the waste water of biochemical gained is passed through to membrane filtration processing again through further purification, obtain pure water.Chinese patent 201010567041.0,201020635352.1 has been introduced papermaking deep processing waste water and has been adopted membrane filtration to carry out the method for recycling utilization, but in implementation process, find in paper waste that calcium ion content is up to 150~400 mg/L, produce a large amount of foulings, the regeneration of waste water is caused to serious difficulty.
Summary of the invention
The object of the invention is to in existing paper waste treatment process, existing cost is higher, usefulness is lower, waste water after treatment mostly is discharge, there is no the problems such as advanced treatment recycle, waste water resource, providing a kind of combines with membrane technique based on chemical decalcification technology, electrochemical techniques, cost is lower, usefulness is higher, makes it the reclamation set of the papermaking deep processing waste water that reaches recycle.
Papermaking deep based on chemical decalcification of the present invention is processed wastewater recycling device and is provided with chemical decalcification system, filtering system, electrolytic system, film separating system, desalination system.
Chemistry decalcification system is processed calcium magnesium, the reduction water hardness of waste water for removing papermaking deep, chemistry decalcification system comprises one-level decalcification reaction tank, stopping valve, secondary decalcification reaction tank and settling tank, one-level decalcification reaction tank connects with the import of stopping valve, the outlet of stopping valve connects the import of secondary decalcification reaction tank, the outlet of secondary decalcification reaction tank connects with the import of stopping valve, the outlet of stopping valve connects with the import of settling tank, and the outlet of settling tank connects the import of filtering system.
One-level decalcification reaction tank in described chemical decalcification system and secondary decalcification reaction tank are also furnished with medicine system, medicine system is provided with grug feeding jar and dosing pump, grug feeding jar outlet connects the import of dosing pump, and dosing pump outlet connects the import of one-level decalcification reaction tank or secondary decalcification reaction tank.
Filtering system is for carrying out filtering separation by the waste water after chemical decalcification, filtering system comprises stopping valve, working shaft, strainer, backwashing pump and cleaning fluid tank, the import of stopping valve connects the outlet of chemical decalcification system, the import of working shaft connects the outlet of stopping valve, water supply pump outlet is taken over the import of filter, outlet one tunnel of strainer connects with electrolytic system, and another road connects cleaning fluid tank through backwashing pump successively.
Filtration in described filtering system is the one in multi-medium filtering, fabric filter element, sand filtration, active sand filtration, filtering cloth filtering pool.
Electrolytic system is for carrying out electrolysis treatment to the water outlet after filtering separation, electrolytic system is provided with stopping valve, working shaft and electrolysis machine, the external filtering system outlet of import of stopping valve, the import of working shaft connects the outlet of stopping valve, water supply pump outlet connects the import of electrolysis machine, and the outlet of electrolysis machine connects with the import of film separating system.
In described electrolytic system, electrolysis machine is provided with power supply and electrolyzer, electrode in described electrolyzer is the one in graphite, titanium, iron, aluminium, zinc, copper, lead, nickel, molybdenum, chromium, alloy and nano-catalytic noble electrode, the top layer of described nano-catalytic noble electrode is coated with the metal oxide inertia catalyst coatings that crystal grain is 10~35nm, and the substrate of described nano-catalytic noble electrode is titanium plate or plastic plate.
Film separating system is removed the particle in waste water and macromolecular colloid, microorganism fast by the centrifugation of film, obtains papermaking and purifies liquid waste.
Described film separating system can be the one in ultrafiltration and MBR.
Described ultrafiltration system is provided with stopping valve, working shaft, ultrafiltration membrane system, backwashing pump, water-dialyzing basin and valve, the import of stopping valve connects the outlet of electrolysis machine, the outlet of stopping valve connects the import of working shaft, the water-dialyzing that water supply pump outlet connects import, the ultrafiltration membrane system of ultrafiltration membrane system exports a road and connects water-dialyzing basin, another road connects water-dialyzing basin through backwashing pump, the condensed water of ultrafiltration membrane system through pipeline and valve return to recycle in electrolytic system; Described ultrafiltration system molecular weight cut-off is 1000~100000MWCO, working conditions is: normal temperature~45 DEG C, ultrafiltration system is the one of immersion ultrafiltration, pillar ultrafiltration, tubular type ultrafiltration, spiral wound or plate-type hyperfiltration, the operating pressure of immersion ultrafiltration is-1~-50kPa, and the operating pressure of pillar ultrafiltration, tubular type ultrafiltration, spiral wound and plate-type hyperfiltration is 3~300kPa.
Described MBR system is provided with stopping valve, MBR reaction tank, MBR membrane module, gas blower, aerator, residual sea water pump, go out water pump, elementary reuse water basin, electrolytic system gained is purified waste water and is connect the import of MBR reaction tank by water inlet pipe through stopping valve, MBR membrane module is immersed in MBR reaction tank, aerator by gas blower and distribution carries out aeration to it, the outlet of MBR reaction tank picks out the import of water pump, the filtrate (water) producing is collected the high-purity regenerated water of elementary reuse water basin for further utilizing for production cocycle through desalination system desalination, a small amount of mud is through residual sea water pump suction discharge, the membrane module of described MBR system is selected from the one in Pvdf Microporous Hollow Fiber Membrane, polypropylene hollow fiber membrane, ps hollow fiber uf membrane, polyether sulphone hollow fibre film, polyacrylonitrile hollow fiber membrane and PVC hollow fiber membrane, the membrane pore size of the MBR membrane module of described MBR system is 0.10~0.2 μ m, and operating pressure is-1~-50kPa, and working temperature is 5~45 DEG C.
Described ultrafiltration system or MBR system also comprise chemical cleaning system, chemical cleaning system is for cleaning the membrane module of ultrafiltration or MBR system, chemical cleaning system is provided with cleaning fluid tank, chemical cleaning pump and stopping valve, the outlet of cleaning fluid tank connects the import of chemical cleaning pump, and matting pump outlet connects ultra-filtration membrane or MBR system through stopping valve.
Desalination system is by film separating system gained water-dialyzing through separating to obtain water-dialyzing and condensed water through desalination system, water-dialyzing enters basin and obtains reuse water, and condensed water is back to electrolytic system, redundance discharge.Described desalination system is provided with stopping valve, working shaft, desalting plant, reuse water basin, stopping valve, the import of stopping valve connects the outlet of film separating system, the water-dialyzing outlet that the outlet of stopping valve connects the import of working shaft, import that water supply pump outlet connects desalting plant, desalting plant connects stopping valve and reuse water basin successively, and the condensed water outlet of desalting plant flow to electrolytic system through stopping valve.
Described desalination system is nanofiltration, reverse osmosis, just infiltration, electrodialysis, capacitive adsorption, ion-exchange or the one of filling electrodialysis (EDI).
Nanofiltration membrane component in described nanofiltration is the one of tubular membrane component, rolled membrane module or plate film assembly, and operating pressure is 6~45bar, and working temperature is 20~45 DEG C, and optimum temps is 35~40 DEG C.
The reverse osmosis membrane assembly of described reverse osmosis is rolled membrane module, and mould material is cellulose acetate film or composite membrane in organic membrane, and the molecular weight cut-off of mould material is 50~200MWCO, and entrance pressure can be 6.0~45.0bar, goes out to press to can be 4.5~33.5 bar.
The described membrane module just permeating is the one in plate and frame module, rolled membrane module, tubular membrane component and packet mode membrane module.
Described electrodialytic working conditions is working pressure 0.5~3.0 ㎏/cm
2, operating voltage 50~250V, strength of current 1~3A.
The working conditions of described capacitive adsorption is that volts DS is 110V ~ 2 × 10
6v.
The ion-exchanger that described ion-exchange is used is divided into inorganic ion exchanger and the large class of organic ion exchanger two, inorganic ion exchanger has natural zeolite and synthetic zeolite etc., and organic exchange resin is the one in strong-acid cation-exchange resin, weakly acidic cationic exchanger resin, strong anion-exchange resin, weak basic anion exchange resin, resin and organic polymeric adsorbent etc.
Described filling electrodialysis (EDI) is a kind of separating desalination technique that electrodialysis and ion-exchange are organically combined, fill electrodialysis unit water inlet require for resistivity be 0.025~0.5M Ω cm.
Technical scheme of the present invention is: papermaking deep is processed waste water → chemical decalcification → filtration → electrolysis → membrane sepn (ultrafiltration/MBR) → desalination system → reuse water.
The present invention had both overcome the defect of alone membrane filtration separating treatment or adsorption treatment high cost, the treatment effect that has overcome again conventional paper waste method is undesirable, the defects such as the contaminated wastewater environment of discharge, process purification of waste water and recycle and reuse by existing papermaking deep.Compared with the prior art, there is following outstanding advantages:
(1) papermaking deep is processed waste water through processing, and 70%~85% can recycling utilization, has both reduced discharge of wastewater, avoid waste water environmental pollution, reduce again water resource waste, can also make the recirculated water cost of regeneration lower than tap water price, economical rationality, produces good economic benefit.
(2) remove after false hardness (supercarbonate) by the one-level decalcification reaction of chemical decalcification system, then make carbonate react generation carbonate deposition with calcium ions and magnesium ions through secondary decalcification reaction tank, then with FeSO
4flocculate mutually with coagulant aidss such as polyphenyl alkene acid amides (PAM), be gathered into thick alumina blossom particles, in settling tank, settle down, final effective elimination papermaking deep is processed high-concentration Ca, the magnesium ion in waste water, reduce water hardness, prevent equipment scaling, ensure that subsequent technique is smooth, steady running.
(3) further reduce COD by nano-catalytic electrolysis, the one, can make the reclamation rate of waste water improve, both reduced discharge of wastewater, avoid waste water environmental pollution, reduce again water resource waste; The 2nd, can kill the microorganisms such as the bacterium in waste water, the biological pollution of eradicating follow-up nanofiltration membrane and reverse osmosis membrane, significantly reduces the wash number of nanofiltration membrane and reverse osmosis membrane, reduce the clean regeneration cost of film, improve the service efficiency of film, extend the work-ing life of film, reduce film replacement cost.
(4) after film separating system is processed, particle and macromolecular colloid compound in waste water are further removed, for follow-up technique is created good condition of water quality, to further decompose pollutant in water by the oxygenolysis of microorganism in MBR system simultaneously, utilize the efficient rejection effect of film, the indexs such as SS, colourity, pollutent are effectively removed.
(5) significantly reduce water consumption index and the discharge of wastewater index of ton paper, improve business economic technical indicator.
The alleged papermaking deep of the present invention is processed waste water and is referred to paper waste second pond water outlet after traditional filtration, flocculation treatment, reaches the waste water of more than three grades emission standard.
Brief description of the drawings
Fig. 1 is the structural representation that the present invention is based on the papermaking deep processing wastewater recycling device membrane sepn employing ultrafiltration system of chemical decalcification;
Fig. 2 is the structural representation that the present invention is based on the papermaking deep processing wastewater recycling device membrane sepn employing MBR system of chemical decalcification;
The structural representation of Fig. 3 medicine system of the present invention.
Embodiment
The present invention is that it is made up of chemical decalcification system, filtering system, electrolytic system, film separating system and desalination system in the purification to papermaking deep processed waste water that composition, character and the existing processing scheme of existing papermaking deep processing waste water are goed deep into completing after the comparative study of system and the design of reclamation set.
The present invention is further illustrated in connection with accompanying drawing for embodiment below.
Referring to Fig. 1 and Fig. 2, the papermaking deep based on chemical decalcification of the present invention is processed wastewater recycling device and is comprised:
Chemistry decalcification system: chemical decalcification system is processed calcium magnesium, the reduction water hardness of waste water for removing papermaking deep, chemistry decalcification system is provided with one-level decalcification reaction tank 11, stopping valve 12, secondary decalcification reaction tank 13, stopping valve 14, settling tank 15, one-level decalcification reaction tank 11 connects with the import of stopping valve 12, the outlet of stopping valve 12 connects the import of secondary decalcification reaction tank 13, the outlet of secondary decalcification reaction tank 13 connects with the import of stopping valve 14, the outlet of stopping valve 14 connects with the import of settling tank 15, and the outlet of settling tank 15 connects the import of filtering system.
Medicine system: with reference to Fig. 3, medicine system is for adding decalcifying agent and coagulating agent to waste water, and medicine system is provided with lime grug feeding jar 16, dosing pump 161, Na
2cO
3grug feeding jar 17, dosing pump 171, FeSO
4grug feeding jar 18, dosing pump 181, PAM grug feeding jar 19, dosing pump 191; The outlet of lime grug feeding jar 16 connects the import of dosing pump 161, and the outlet of dosing pump 161 connects the import of one-level decalcification reaction tank 11; Na
2cO
3the outlet of grug feeding jar 17 connects the import of dosing pump 171, and the outlet of dosing pump 171 connects the import of secondary decalcification reaction tank 13; FeSO
4the outlet of grug feeding jar 18 connects the import of dosing pump 181, and the outlet of dosing pump 181 connects the import of secondary decalcification reaction tank 13; The outlet of PAM grug feeding jar 19 connects the import of dosing pump 191, and the outlet of dosing pump 191 connects the import of secondary decalcification reaction tank 13.
Filtering system: filtering system is for carrying out filtering separation by the waste water after chemical decalcification, and filtering system is provided with stopping valve 21, working shaft 22, strainer 23, stopping valve 24, backwashing pump 25 and cleaning fluid tank 26; The import of stopping valve 21 connects the outlet of chemical decalcification system, the import of working shaft 22 connects the outlet of stopping valve 21, the import of filter 23 is taken in the outlet of working shaft 22, and outlet one tunnel of strainer 23 connects with electrolytic system, and another road connects cleaning fluid tank 26 through backwashing pump 25 successively.
Electrolytic system: electrolytic system is for carrying out electrolysis treatment to the water outlet after filtering separation, and electrolytic system is provided with stopping valve 31, working shaft 32 and electrolysis machine 33; The external filtering system relief outlet of import of stopping valve 31, the import of working shaft 32 connects the outlet of stopping valve 31, and the outlet of working shaft 32 connects the import of electrolysis machine 33, and the outlet of electrolysis machine 33 connects with the import of film separating system.
Film separating system: film separating system for the centrifugation by film particle and macromolecular colloid, the microorganism to waste water remove fast, obtain papermaking and purify liquid waste.Film separating system can be the one in ultrafiltration and MBR.
With reference to Fig. 1, ultrafiltration system is provided with stopping valve 41, working shaft 42, ultrafiltration membrane system 43, backwashing pump 44, stopping valve 45, water-dialyzing basin 46 and valve 47, the import of stopping valve 41 connects the outlet of electrolysis machine 33, the outlet of stopping valve 41 connects the import of working shaft 42, the outlet of working shaft 42 connects the import of ultrafiltration membrane system 43, the water-dialyzing outlet of ultrafiltration membrane system 43 connects water-dialyzing basin 46 through backwashing pump 44, stopping valve 45 successively, and the condensed water of ultrafiltration membrane system 43 is back in electrolytic system and reuses through valve 47.
With reference to Fig. 2, MBR system, is provided with stopping valve 41, MBR membrane module 42, gas blower 43, aerator 44, MBR reaction tank 45, residual sea water pump 46, goes out water pump 47 and elementary reuse water basin 48.The import of stopping valve 41 connects the outlet of electrolysis machine 33, the outlet of stopping valve 41 successively through MBR reaction tank 45, go out water pump 47 and enter elementary reuse water basin 48.
Ultrafiltration or MBR chemical cleaning system: chemical cleaning system is used for cleaning ultrafiltration or MBR system, chemical cleaning system is provided with cleaning fluid tank 51, chemical cleaning pump 52 and stopping valve 53, the outlet of cleaning fluid tank 51 connects the import of chemical cleaning pump 52, and the outlet of chemical cleaning pump 52 connects ultrafiltration or MBR system through stopping valve 53.
Desalination system: desalination system pumps into desalination system by film separating system gained water-dialyzing with pump, separates to obtain water-dialyzing and condensed water through desalination system, and water-dialyzing enters basin and obtains reuse water; A condensed water part is back to electrolytic system, redundance discharge.Described desalination system can be nanofiltration, reverse osmosis, just infiltration, electrodialysis, capacitive adsorption, ion-exchange or the one of filling electrodialysis (EDI).
Desalination system is provided with stopping valve 61, working shaft 62, desalting plant 63, stopping valve 64, reuse water basin 65, stopping valve 66.The import of stopping valve 61 connects the outlet of film separating system water-dialyzing basin, the outlet of stopping valve 61 is successively through working shaft 62, desalting plant 63, the water-dialyzing outlet of desalting plant 63 connects the import of reuse water basin 65 through stopping valve 64, the backflow condensed water outlet of desalting plant 63 is back to electrolytic system through stopping valve 66.
Provide below in conjunction with Fig. 1, Fig. 2 and Fig. 3 the specific embodiment of processing wastewater recycling device based on the papermaking deep of chemical decalcification.
Embodiment 1
800 ton per day papermaking deeps are processed the reuse method of waste water.
It is as shown in table 1 after measured that described papermaking deep is processed waste water quality index.
Table 1 papermaking deep is processed the water-quality guideline of waste water
Sequence number |
Project |
Unit |
Measured value |
Sequence number |
Project |
Unit |
Measured value |
1 |
COD
Cr |
mg/L |
150 |
4 |
Colourity |
|
100 |
2 |
SS |
mg/L |
120 |
5 |
Ca |
mg/L |
400 |
3 |
Specific conductivity |
μS/cm |
1600 |
6 |
Hardness |
mmol/L |
9.9 |
(1) chemical decalcification
Second pond water outlet after papermaking biochemical treatment (being that papermaking deep is processed waste water) flows into one-level decalcification reaction tank 11 through pipeline, under agitation first add appropriate lime saturated solution adjust pH to 8.5 by chemicals dosing plant, remove after false hardness (supercarbonate), flow into secondary decalcification reaction tank 13, add the Na of 600mg/L
2cO
3, carbonate is reacted with calcium ions and magnesium ions and generate carbonate deposition, then add the FeSO of 5mg/L
4, then add Na
2cO
3anti-adjust pH to 8.5, finally adds the polyacrylamide (PAM) of 1mg/L, enters settling tank 15 after reacting completely, and carries out precipitate and separate, processes calcium magnesium in waste water, reduces water hardness thereby remove papermaking deep, prevents that follow-up equipment, facility are because Ca
2+excessive concentration and fouling; Throw out (being mud) is sent in sludge sump through pump and pipeline, finally in sludge dehydration device, carries out filtering separation, and reclaims calcium carbonate, and waste water enters next step and filters;
(2) filter
Waste water after chemical decalcification is pumped into filtering system and carry out filtering separation, further except SS and colloid in anhydrating;
The above-mentioned multi-medium filtering that is filtered into.Filtration can be the one in multi-medium filtering, fabric filter element, sand filtration, active sand filtration, filtering cloth filtering pool.
(3) electrolysis
Waste water after filtering is pumped into electrolysis machine 33 electrolysis, with the organic macromolecule of degrading, remove colourity, improve the biodegradability of waste water, the adjacent two interelectrode voltages of electrolysis machine 33 are 2V, and current density is 200mA/cm
2;
(4) membrane sepn
Waste water after electrolysis enters film separating system, remove particle, macromolecular colloid compound and the microorganism in waste water by membrane sepn effect, obtain water-dialyzing and condensed water, water-dialyzing enters desalting treatment system, and condensed water flow to recycle in the electrolysis machine 33 of step (3) through back of pipeline;
Described film separating system is MBR system.The membrane module of MBR system is selected from the one in Pvdf Microporous Hollow Fiber Membrane, polypropylene hollow fiber membrane, ps hollow fiber uf membrane, polyether sulphone hollow fibre film, polyacrylonitrile hollow fiber membrane and PVC hollow fiber membrane; The membrane pore size of MBR membrane module is 0.10~0.2 μ m, and operating pressure is-1~-50kPa, and working temperature is 5~45 DEG C.
(5) desalination system
Membrane sepn gained water-dialyzing pumps into desalination system with pump, obtains water-dialyzing and condensed water through desalination system filtering separation, and water-dialyzing enters basin and obtains reuse water; A condensed water part is back to electrolytic system, redundance discharge.
Described desalination system is reverse osmosis system.Reverse osmosis membrane system adopts molecular weight cut-off to can be the reverse osmosis membrane of 50~200MWCO, and membrane module is tubular membrane component or rolled membrane module, and entrance pressure can be 6.0~35.0bar, goes out to press to can be 4.5~33.5 bar.
Reuse water water-quality guideline is as shown in table 2 after measured.
The water-quality guideline of table 2 reuse water
Sequence number |
Project |
Unit |
Measured value |
Sequence number |
Project |
Unit |
Measured value |
1 |
COD
Cr |
mg/L |
8 |
4 |
Colourity |
|
8 |
2 |
SS |
mg/L |
≤1 |
5 |
Ca |
mg/L |
45 |
3 |
Specific conductivity |
μS/cm |
80 |
6 |
Hardness |
mmol/L |
1.1 |
Embodiment 2
5000 ton per day papermaking deeps are processed the reuse method of waste water.
It is as shown in table 3 after measured that described papermaking deep is processed waste water quality index.
Table 3 papermaking deep is processed the water-quality guideline of waste water
Sequence number |
Project |
Unit |
Measured value |
Sequence number |
Project |
Unit |
Measured value |
1 |
COD
Cr |
mg/L |
100 |
4 |
Colourity |
|
150 |
2 |
SS |
mg/L |
120 |
5 |
Ca |
mg/L |
150 |
3 |
Specific conductivity |
μS/cm |
1800 |
6 |
Hardness |
mmol/L |
4 |
(1) chemical decalcification
Second pond water outlet after papermaking biochemical treatment (being that papermaking deep is processed waste water) flows into one-level decalcification reaction tank 11 through pipeline, under agitation first add appropriate lime saturated solution adjust pH to 9 by chemicals dosing plant, remove after false hardness (supercarbonate), flow into secondary decalcification reaction tank 13, add the Na of 100mg/L
2cO
3, carbonate is reacted with calcium ions and magnesium ions and generate carbonate deposition, then add the FeSO of 2mg/L
4, then add Na
2cO
3anti-adjust pH to 8, finally adds the polyacrylamide (PAM) of 3mg/L, enters settling tank 15 after reacting completely, and carries out precipitate and separate, processes calcium magnesium in waste water, reduces water hardness thereby remove papermaking deep, prevents that follow-up equipment, facility are because Ca
2+excessive concentration and fouling; Throw out (being mud) is sent in sludge sump through pump and pipeline, finally in sludge dehydration device, carries out filtering separation, and reclaims calcium carbonate, and waste water enters next step and filters;
(2) filter
Waste water after chemical decalcification is pumped into filtering system and carry out filtering separation, further except SS and colloid in anhydrating;
The above-mentioned multi-medium filtering that is filtered into.Filtration can be the one in multi-medium filtering, fabric filter element, sand filtration, active sand filtration, filtering cloth filtering pool.
(3) electrolysis
Waste water after filtering is pumped into electrolysis machine 33 electrolysis, with the organic macromolecule of degrading, remove colourity, improve the biodegradability of waste water, the adjacent two interelectrode voltages of electrolysis machine 33 are 12V, and current density is 10mA/cm
2;
(4) membrane sepn
Waste water after electrolysis enters film separating system, remove particle, macromolecular colloid compound and the microorganism in waste water by membrane sepn effect, obtain water-dialyzing and condensed water, water-dialyzing enters desalting treatment system, and condensed water flow to recycle in the electrolysis machine 33 of step (3) through back of pipeline;
Described film separating system is ultrafiltration system, and ultrafiltration is immersion ultrafiltration, and working conditions is: normal temperature~45 DEG C, and operating pressure is-1~-50kPa; Ultrafiltration can be the one of immersion ultrafiltration, pillar ultrafiltration, tubular type ultrafiltration, spiral wound or plate-type hyperfiltration.
(5) desalination system
Membrane sepn gained water-dialyzing, through pumping into desalination system with pump, obtains water-dialyzing and condensed water through desalination system filtering separation, and water-dialyzing enters basin and obtains reuse water; A condensed water part is back to electrolytic system, redundance discharge.
Described desalination system is reverse osmosis system.Reverse osmosis membrane system adopts molecular weight cut-off to can be the reverse osmosis membrane of 50~200MWCO, and membrane module is tubular membrane component or rolled membrane module, and entrance pressure can be 6.0~35.0bar, goes out to press to can be 4.5~33.5 bar.
Reuse water water-quality guideline is as shown in table 4 after measured.
The water-quality guideline of table 4 reuse water
Sequence number |
Project |
Unit |
Measured value |
Sequence number |
Project |
Unit |
Measured value |
1 |
COD
Cr |
mg/L |
10 |
4 |
Colourity |
|
5 |
2 |
SS |
mg/L |
≤1 |
5 |
Ca |
mg/L |
30 |
3 |
Specific conductivity |
μS/cm |
100 |
6 |
Hardness |
mmol/L |
0.75 |
Embodiment 3
20000 ton per day papermaking deeps are processed the reuse method of waste water.
It is as shown in table 5 after measured that described papermaking deep is processed waste water quality index.
Table 5 papermaking deep is processed the water-quality guideline of waste water
Sequence number |
Project |
Unit |
Measured value |
Sequence number |
Project |
Unit |
Measured value |
1 |
COD
Cr |
mg/L |
150 |
4 |
Colourity |
|
120 |
2 |
SS |
mg/L |
80 |
5 |
Ca |
mg/L |
200 |
3 |
Specific conductivity |
μS/cm |
1200 |
6 |
Hardness |
mmol/L |
5 |
(1) chemical decalcification
Second pond water outlet after papermaking biochemical treatment (being that papermaking deep is processed waste water) flows into one-level decalcification reaction tank 11 through pipeline, under agitation first add appropriate lime saturated solution adjust pH to 9.5 by chemicals dosing plant, remove after false hardness (supercarbonate), flow into secondary decalcification reaction tank 13, add the Na of 350mg/L
2cO
3, carbonate is reacted with calcium ions and magnesium ions and generate carbonate deposition, then add the FeSO of 10mg/L
4, then add Na
2cO
3anti-adjust pH to 9, finally adds the polyphenyl propionic acid amide (PAM) of 2mg/L, enters settling tank 15 after reacting completely, and carries out precipitate and separate, processes calcium magnesium in waste water, reduces water hardness thereby remove papermaking deep, prevents that follow-up equipment, facility are because Ca
2+excessive concentration and fouling; Throw out (being mud) is sent in sludge sump through pump and pipeline, finally in sludge dehydration device, carries out filtering separation, and reclaims calcium carbonate, and waste water enters next step and filters;
(2) filter
Waste water after chemical decalcification is pumped into filtering system and carry out filtering separation, further except SS and colloid in anhydrating;
Above-mentionedly be filtered into active sand filtration.Filtration can be the one in multi-medium filtering, fabric filter element, sand filtration, active sand filtration, filtering cloth filtering pool.
(3) electrolysis
Waste water after filtering is pumped into electrolysis machine 33 electrolysis, with the organic macromolecule of degrading, remove colourity, improve the biodegradability of waste water, the adjacent two interelectrode voltages of electrolysis machine 33 are 2V, and current density is 320mA/cm
2;
(4) membrane sepn
Waste water after electrolysis enters film separating system, remove particle, macromolecular colloid compound and the microorganism in waste water by membrane sepn effect, obtain water-dialyzing and condensed water, water-dialyzing enters desalting treatment system, and condensed water flow to recycle in the electrolysis machine 33 of step (3) through back of pipeline;
Described film separating system is MBR system.The membrane module of MBR system is selected from the one in Pvdf Microporous Hollow Fiber Membrane, polypropylene hollow fiber membrane, ps hollow fiber uf membrane, polyether sulphone hollow fibre film, polyacrylonitrile hollow fiber membrane and PVC hollow fiber membrane; The membrane pore size of MBR membrane module is 0.10~0.2 μ m, and operating pressure is-1~-50kPa, and working temperature is 5~45 DEG C.
(5) desalination system
Membrane sepn gained water-dialyzing pumps into desalination system with pump, obtains water-dialyzing and condensed water through desalination system filtering separation, and water-dialyzing enters basin and obtains reuse water; A condensed water part is back to electrolytic system, redundance discharge.
Described desalination system is nanofiltration system.The membrane module of described nanofiltration system is the one of tubular membrane component, rolled membrane module or plate film assembly, and operating pressure is 6~45bar, and working temperature is 20~45 DEG C, and optimum temps is 35~40 DEG C.
Reuse water water-quality guideline is as shown in table 6 after measured.
The water-quality guideline of table 6 reuse water
Sequence number |
Project |
Unit |
Measured value |
Sequence number |
Project |
Unit |
Measured value |
1 |
COD
Cr |
mg/L |
8 |
4 |
Colourity |
|
6 |
2 |
SS |
mg/L |
≤1 |
5 |
Ca |
mg/L |
60 |
3 |
Specific conductivity |
μS/cm |
60 |
6 |
Hardness |
mmol/L |
1.5 |