CN1242938C - Deep purification treatment method for waste water - Google Patents
Deep purification treatment method for waste water Download PDFInfo
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- CN1242938C CN1242938C CN 03134002 CN03134002A CN1242938C CN 1242938 C CN1242938 C CN 1242938C CN 03134002 CN03134002 CN 03134002 CN 03134002 A CN03134002 A CN 03134002A CN 1242938 C CN1242938 C CN 1242938C
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Abstract
The present invention relates to a method for deeply removing COD and odour chemical substances in wastewater which reaches the oil refining standard. The treatment method comprises the steps: micro flocculating, filtering fiber bundles and absorbing activated carbon fibers, wherein the activated carbon fibers have a certain volume of middle holes, and can absorb pollutants with different molecular weight. COD and odour chemical substances in wastewater which is treated by the method are deeply eliminated, and the wastewater can substitute for fresh water for recycling as industrial feedwater, such as process water in an oil refinery, circulation water, replenishing water, greening water, fire-fighting water, etc. Thereby, the consumption of an oil refinery to fresh water is reduced, and the water-saving purpose is achieved. The method has advantages that the process is simple, and the construction investment, the occupation area and the operating cost of treating and recycling wastewater are reduced. The mehtod has high economic value.
Description
1, technical field
The present invention relates to a kind of waste water advanced purifying treatment process, the qualified discharge waste water of particularly refining oil replaces the fresh water reuse to do the treatment process of refinery processes water, circulating water system, greening and water for fire-fighting purpose behind deep purifying.
2, background technology
One of key issue that refinery qualified discharge waste water recycling need solve is COD and the stink chemical substance that needs in the deep removal waste water, to avoid reuse water oil refining process and environment is caused detrimentally affect.Consider simultaneously, must guarantee also that the treatment technology flow process is simple, investment and working cost be low based on economy.
Along with the development of adsorption technology and sorbing material, a class has obtained fast development to the activated carbon fiber that organism has the wide spectrum adsorption effect in recent years, has particularly obtained widespread use in solvent recuperation and off gas treatment.Activated carbon fiber is by various former silky fibres, make through charing and activation as fibers such as artificial silk, coal or petroleum pitch, polyacrylonitrile, polyvinyl alcohol, phenolic aldehyde systems, because it has the microvoid structure (the main distribution on the outer surface) of huge outside surface and specific surface, singlet state, multiple functional group, Fibre diameter is very thin and possess characteristics such as higher flexibility and intensity, makes it demonstrate great advantage in adsorption applications.As comparing with gac, eliminated and started to control the adsorption and diffusion resistance of making usefulness, show adsorption desorption speed, easy reproducibility and effective adsorption capacity fast.Just because of these advantages that activated carbon fiber showed, many people have begun this sorbing material is applied on the purifying treatment of water and waste water, propose to have with a kind of that micropore distributes and the activated carbon fiber purified tap water of high adsorption rate as US5607595, adsorb and removal water in free chlorine, deleterious haloform and stink material etc.US4696742 proposes with a kind of BET specific surface area 800~2000m
2/ g, using pore volume is 5 * 10 with the specific surface area ratio
-4~14.5 * 10
-4With 3.5 * 10
-4~8.5 * 10
-4Two kinds of polyacrylonitrile active carbon fibers carry out purifying treatment to water, remove the chemicals that have the relative broad range molecular weight in the water.Zhao Guang etc. (" handling the research of tridemorph agricultural chemicals waste water with carbon fiber adsorption and catalytic combustion ", chemical industry environmental protection, 1995,15 (3)) proposes to handle the tridemorph agricultural chemicals waste water with carbon fiber adsorption and catalytic combustion in addition; Zhou Lili etc. (" activated carbon fiber is to the Study on adsorption properties of N-BUTYL ACETATE in the aqueous solution ", Shenyang chemical industry, 1996, (2)) have done the Study on adsorption properties with N-BUTYL ACETATE in the carbon fiber adsorption and catalytic combustion aqueous solution; Xu Zhida etc. (" activated carbon fiber Refinery Wastewater prospect ", Treatment of Industrial Water, 1998,18 (2)) use the activated carbon fiber Refinery Wastewater.Method that above patent and document are mentioned and the result who obtains have proved the useful effect of activated carbon fiber in water and purification of waste water processing really.But be inappropriate with above related patent and COD and the stink chemical substance in the method advanced treatment oil refining qualified discharge waste water on the whole.At first contain a large amount of polymer colloids, humic acid, protein, microbial metabolites etc. in the waste discharge; usually activated carbon fiber to they be do not have adsorbing; in treating processes; they can stick to the outside surface of activated carbon fiber; stop up thereby made adsorbing micropore that the surface take place, finally have influence on the adsorption effect and the regeneration of activated carbon fiber.Secondly, organic constituent in the waste discharge is up to more than thousands of kinds, the organic substance that some high molecular in the adsorption treatment process (is more than 500 as relative molecular weight) and molecular diameter are higher has directly influenced the adsorption efficiency and the water outlet effect of activated carbon fiber owing to can't can not get absorption by the micropore of activated carbon fiber.As before the present invention, once oil refining qualified discharge water quality having been carried out molecular weight distribution determination, measurement result show relative molecular weight in the waste water less than 500 organic constituent account for 50%~65% (, as follows) in COD, 500~3000 account for 10%~20%, suspended substance and colloid thing greater than 3000 account for 25%~35%.Directly handle the oil refining waste water up to standard of this composition with above-mentioned microporous type activated carbon fiber commonly used, only can effectively remove relative molecular weight wherein, make the theoretical clearance of waste water COD not be higher than 65% less than 500 organic constituent.And in the treating processes because the surface accumulation takes place in suspended substance and colloid thing on the carbon fiber adsorption and catalytic combustion layer, make the obstruction of activated carbon fiber micropore, influenced adsorption effect and regeneration.To this, the present invention proposes a kind of degree of depth removal method of refining oil COD and stink chemical substance in the waste water up to standard, the waste water up to standard that it is characterized in that at first will refining oil is handled by little flocculation and fibre bundle filtration, remove the COD and the stink thing of suspended substance, colloid thing and corresponding composition in the waste water on the one hand, avoid causing obstruction on the other hand the carbon fiber adsorption and catalytic combustion layer.Again waste water is carried out adsorption treatment by the activated carbon fiber that contains the distribution of suitable proportion mesopore volume, remove the low and higher organic constituent of relative molecular weight in the waste water simultaneously, reach effect COD in the waste water and stink chemical substance deep removal.
3, summary of the invention
The present invention is directed to the particular case of oil refining qualified discharge waste water, a kind of method that can reduce COD in the waste water simply, effectively and contain stink substance is provided, and the waste water after the inventive method is handled can be used for aspects such as refinery processes water, circulating water system, greening and water for fire-fighting purpose.
The inventive method specific embodiment is: refinery qualified discharge waste water adds flocculation agent and carries out little flocculation treatment, enter fiber bundle filter then, adopt at last to have the carbon fiber adsorption and catalytic combustion device processing that the suitable proportion mesopore volume distributes, water outlet can reuse.The concrete pore distribution that wherein has the activated carbon fiber of suitable proportion mesopore is: the mesopore scope is 3~10nm, is preferably 4~6nm, and mesopore volume is 30%~60% with the ratio of fiber total pore volume, is preferably 35%~50%.
The inventive method is by measuring the concrete foreign matter content and the different sorts of refinery qualified discharge waste water, determined the processing method that deep purifying is handled, particularly adopted activated carbon fiber to carry out adsorption treatment, can effectively reduce COD and stink substance in the waste water with certain central hole structure.The inventive method is simple, processing cost is low, effluent quality is good, can replace fresh water to be used for aspects such as refinery processes water, circulating water system, greening and water for fire-fighting purpose, has reached the double effects of saving water resources and reducing wastewater discharge simultaneously.
4, embodiment
The present invention proposes a kind of degree of depth removal method of refining oil COD and stink chemical substance in the waste water up to standard, refine oil waste water up to standard through little flocculation, fibre bundle filtration with contain the carbon fiber adsorption and catalytic combustion that the suitable proportion mesopore volume distributes and handle, make COD and stink chemical substance in the waste water obtain deep removal.Concrete scheme is: add an amount of flocculation agent in waste discharge, the suspended substance in the water, colloid, humic acid, protein, microbial metabolites and macromolecule organic etc. are provided bridge formation, breakdown of emulsion and take off steady effect; By fibre bundle filtration, make these materials be trapped and be adsorbed on the fibrous bundle surface then, effectively removed; Filter water outlet and handle by the adsorption unit that the activated carbon fiber that contains appropriate ratio mesopore volume is housed again, make the dissolved organic matter of different molecular weight and molecular diameter and stink chemicals can both obtain higher absorption.
In the present invention, the waste water up to standard of refining oil at first is added into a certain amount of flocculation agent, and mix, the mixing rest time that preferably keeps 5~10 minutes is to guarantee in the waste water quilt such as suspended substance, colloid, humic acid, protein, microbial metabolites and macromolecule organic fully bridge formation, breakdown of emulsion and take off surely.Flocculation agent can be selected common poly-aluminium for use, as inorganic type flocculation agents such as polymerize aluminum chloride, polyaluminium sulfates, and dosage 10~20mg/L; Also can select polymer organic floculants such as polyacrylamide for use, dosage O.5~2mg/L.The waste water that will flocculate then filters by fiber bundle filter.
The structure of fiber bundle filter, operation and fibrous bundle cleaning and regeneration can adopt general pattern in this area and method, as strainer mainly by fixedly porous plate, fibrous bundle, active multi-hole plate, air distribution plate etc. are formed; Common operational condition is: filter operation pressure 0.02~0.6MPa, void tower volume space velocity 20~60h-1 (residence time of waste water in bed is 3~1 minutes); Common fibrous bundle cleaning and regeneration condition is air and clear water backmixing or replaces cleaning, rinse water pressure 0.2~0.6MPa, rinse water flow velocity 20~30m/h, cleaning air pressure 0.5~0.6MPa, cleaning air intensity 0.04~0.06m
3/ m
2.s, process rinse water consumption is 2%~5% etc. of a wastewater treatment capacity.The high-concentration waste liquid that cleaning and regeneration produces enters refinery waste sludge treatment system through dehydration or after not dewatering.
Handle by little flocculation of the present invention and fibre bundle filtration, the COD in the waste water is removed 20%~30%, and the stink chemical substance is also partly removed.
Water outlet behind fibre bundle filtration is done further processing by the adsorption unit of activated carbon fiber of the present invention, solvability COD and stink chemical substance in the deep removal water.The activated carbon fiber that adopts among the present invention is the activated carbon fiber that contains appropriate ratio mesopore volume, so-called mesopore volume refers to that fiber contains the pore volume of aperture 2~50nm, and appropriate ratio is meant the absolute magnitude of contained mesopore volume in the fiber or accounts for the relative content of fiber total pore volume.Consider the molecular weight distribution of handling organic constituent in the waste water, the mesopore scope of activated carbon fiber of the present invention is selected 3~10nm, is preferably 4~6nm; Mesopore volume is 30%~60% with the ratio of fiber total pore volume, is preferably 35%~50%.Adopt the activated carbon fiber that contains appropriate ratio mesopore volume of the present invention to handle, with the micropore that accounts for activated carbon fiber pore volume 40%~70% (aperture is less than 2nm) with account for 30%~60% mesopore and adsorb low molecule (relative molecular weight is below 500) and macromolecule organic and stink chemical substance in the waste water respectively, the degree of depth is removed COD and the stink in the waste water.
The activated carbon fiber that contains appropriate ratio mesopore volume of the present invention can be used (" by modified polyacrylonitrile precursor system mesopore activated carbon fiber ", new carbon, the fourth phases such as Chinese patent 95119030.X and Zhang Yinzhi; " carbon black additive is to the influence of porosity in the activated carbon fiber ", the plain technology of charcoal, 1997, (6)) propose in the spinning polyacrylonitrile fibril, add carbon black, Graphite Powder 99 or gac etc., be prepared through methods such as the preoxidation of routine, charing, steam activations then.Also can adopt method similarly, make viscose glue base, asphaltic base, PVA-based, the phenolic aldehyde base isoreactivity charcoal fiber that the present invention requires the mesopore volume ratio as carbon fibre precursors such as artificial silk, coal or petroleum pitch, polyvinyl alcohol, phenolic aldehyde systems with other.
The activated carbon fiber that aforesaid method is made is loaded on the adsorber of the present invention, and adsorber can adopt conventional design, as mainly being made up of activated carbon fiber, water distribution board, supporting screening plate and hot air system, superheated vapour system etc.After activated carbon fiber reaches adsorption equilibrium, with the air of 200 ℃~500 ℃ superheated vapours, normal temperature~80 ℃ or the alternately regeneration of washing water of warm air and trace.High-concentration waste liquid of being born again and organic exhaust gas feed incinerator and further handle.
In above-mentioned carbon fiber adsorption and catalytic combustion process, in order to guarantee good activated carbon fiber wide spectrum treatment effect and to give full play to its advantage of absorption fast, require to keep the liquid volume air speed of 20~100h-1 in the process, the corresponding residence time is 3.0~0.6 minutes.Every gram activated carbon fiber is handled wastewater volume amount 1~4L.The tamped density of activated carbon fiber requires to reach 0.03~0.3g/cc, and tamped density is excessive, then too compacting of fiber, and the operation resistance is big, is unfavorable for absorption and regeneration; Tamped density is little, then can increase the volume of treatment unit.
By the adsorption treatment of the activated carbon fiber that contains appropriate ratio mesopore volume that the present invention relates to, COD further is removed 60%~70% in the waste water, and stink is eliminated fully.Comprehensive little flocculation of the present invention and fibre bundle filtration are handled, and the total clearance of COD of refining oil in the waste water up to standard reaches more than 80%, and water outlet is lower than 20mg/L, and stink is eliminated fully.
The object of the inventive method suitable treatment comprises oil refining or other industry waste water that refinery passes through the oxidation pond treat effluent and has similarity again after sewage-farm secondary biochemical treatment draining, secondary biochemical treatment, generally be COD100~150mg/L contain the stink wastewater, certainly, if come water water quality above above-mentioned scope or below These parameters, the method that can take to adjust operating parameters meets the demands, and operational condition can be carried out the normal experiment design according to the concrete water quality of coming water.
Embodiment 1
Adopt treatment process of the present invention that domestic certain refinery qualified discharge waste water is removed COD and stink advanced treatment, waste water COD 108mg/L contains serious foul odour.Adopt little flocculation of the present invention, fibre bundle filtration and contain the carbon fiber adsorption and catalytic combustion disposal methods waste water that the suitable proportion mesopore volume distributes.Select poly-aluminium inorganic flocculating agent for use, add-on 10mg/L; Fiber bundle filter body diameter 200mm, fibrous bundle packing height 800mm adopts the bottom-up flow pattern of waste water to filter; Activated carbon fiber absorber body diameter 200mm, virtual height 1200mm, the mesothyrid polyacrylonitrile radical active carbon fiber 4000g of Chinese patent 95119030.X method preparation, BET specific surface area 842m are pressed in filling in the body
2/ g, mean pore size 3.85nm, total pore volume 0.50ml/g, wherein (aperture 3~10nm) volumes are respectively 0.17ml/g and 0.24ml/g for micropore (aperture is less than 2nm) and mesopore.Behind waste water and the poly-aluminium flocculating agent thorough mixing static 10 minutes, with 1m
3The flow velocity of/h is by fiber bundle filter and carbon fiber adsorption and catalytic combustion device, and each period treatment time 20h handles waste water total amount 20m
3, average water outlet COD 18mg/L, the limpid free from extraneous odour of water outlet.Reached the purpose of COD and stink in the deep purifying waste water by the inventive method.
Embodiment 2
Keep other condition of embodiment 1 constant, the mesothyrid viscose glue type activated carbon fiber 3950g of Chinese patent 95119030.X method preparation, BET specific surface area 2233m are pressed in filling in the activated carbon fiber absorber
2/ g, mean pore size 3.55nm, total pore volume 0.40ml/g, wherein micropore and mesopore volume are respectively 0.11ml/g and 0.20ml/g.Each period treatment time 20h handles waste water total amount 20m
3, average water outlet COD 14mg/L, the limpid free from extraneous odour of water outlet.
Comparing embodiment 1
Keep other condition of embodiment 1 constant, replace mesothyrid activated carbon fiber, the BET specific surface area 1098m of activated carbon fiber with at present commercially available viscose-based active carbon fiber
2/ g, mean pore size 1.64nm, total pore volume 0.08ml/g, wherein micropore and mesopore volume are respectively 0.06ml/g and 0.02ml/g.Each period treatment time 20h handles waste water total amount 10m
3, average water outlet COD 46mg/L, the limpid but frowziness slightly of water outlet.
Embodiment 3
Behind the wastewater treatment 20h to embodiment 1, fiber bundle filter is carried out cleaning and regeneration, stop into water after owing to eliminated the hydrodynamicpressure of water, make fiber reach rarefaction, feed 0.05m by strainer bottom air distribution plate
3/ m
2.s 0.5MPa air by the 0.4MPa washing water (filtration water outlet) of strainer top water distribution board feeding flow velocity 20m/h, gathers under diffusing and the hydrodynamic cleaning at bubble simultaneously, makes fiber vertically be in continuous dither state, and cleaning process keeps 20min.The cleaning water outlet is limpid, shows that filtrate cleans fully.Cleaning water consumption is 2% of a wastewater treatment capacity.
Embodiment 4
Behind the wastewater treatment 20h to embodiment 1, the activated carbon fiber in the adsorber is regenerated, stop into water after, feed the air of 0.3MPa by adsorber bottom air distribution plate, keep intensity 0.05m
3/ m
2.s descend 30s, squeeze out the interior remaining waste water of device to the raw water surge tank, feed 250 ℃ superheated vapour (pressure 0.3MPa, intensity 0.04m simultaneously
3/ m
2.s) and 0.3MPa75 ℃ air (intensity 0.04m
3/ m
2.s), feed alternately regenerated carbon fiber of washing water (pressure 0.3MPa, flow velocity 10m/h) by adsorber top again, the time of logical steam and air is 10 minutes, 2 minutes of logical washing water time, process carries out twice, continues 24 minutes altogether, and the carbon fiber adsorption and catalytic combustion performance is recovered.Cleaning process water consumption is 2% of wastewater treatment capacity.
Claims (8)
1, a kind of waste water advanced purifying treatment process, it is characterized in that adopting following process: qualified discharge waste water adds flocculation agent and carries out little flocculation treatment, enter fiber bundle filter then, adopt at last and have the carbon fiber adsorption and catalytic combustion device processing that the suitable proportion mesopore volume distributes, water outlet can reuse, the concrete pore distribution that wherein has the activated carbon fiber of suitable proportion mesopore is: the mesopore scope is 3~10nm, and mesopore volume is 30%~60% with the ratio of fiber total pore volume.
2, in accordance with the method for claim 1, it is characterized in that described mesopore scope is 4~6nm, mesopore volume is 35%~50% with the ratio of fiber total pore volume.
3,, it is characterized in that described little flocculation selects inorganic flocculating agent or organic floculant for use according to claim 1 or 2 described methods.
4, in accordance with the method for claim 3, it is characterized in that described inorganic flocculating agent is selected from polymerize aluminum chloride or polyaluminium sulfate, dosage 10~20mg/L; Described organic floculant is a polyacrylamide, dosage 0.5~2mg/L.
5, in accordance with the method for claim 1, the operational condition that it is characterized in that described fiber bundle filter is: pressure 0.02~0.6MPa, void tower volume space velocity 20~60h
-1
6, in accordance with the method for claim 1, the operational condition that it is characterized in that described carbon fiber adsorption and catalytic combustion treater is: liquid volume air speed 20~100h
-1, every gram activated carbon fiber is handled wastewater volume amount 1~4L.
7, according to claim 1 or 6 described methods, the tamped density that it is characterized in that described carbon fiber adsorption and catalytic combustion treater is 0.03~0.3g/cc.
8, in accordance with the method for claim 1, the regeneration that it is characterized in that described carbon fiber adsorption and catalytic combustion treater can be adopted air or the warm air and the alternately regeneration of washing water of 200 ℃~500 ℃ superheated vapour, normal temperature~80 ℃.
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CN 03134002 CN1242938C (en) | 2003-09-15 | 2003-09-15 | Deep purification treatment method for waste water |
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CN1242938C true CN1242938C (en) | 2006-02-22 |
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Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
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CN102050542B (en) * | 2009-10-27 | 2013-06-05 | 中国石油化工股份有限公司 | Deep treatment method for high-concentration organic wastewater |
CN102442747B (en) * | 2010-10-12 | 2013-06-19 | 中国石油化工股份有限公司 | Treatment method for discharging naphthenic acid wastewater within controlling index of national standard |
CN102336482A (en) * | 2011-06-13 | 2012-02-01 | 桂林理工大学 | Method for treating low-temperature low-turbidity source water through combination of zeolite powder and iron salt |
CN106546543A (en) * | 2016-11-04 | 2017-03-29 | 天津大学 | A kind of petrifaction sewage COD feature distribution research methods |
CN108706657B (en) * | 2018-06-11 | 2021-12-07 | 北京伟创力科技股份有限公司 | Adsorption filter for common oil field wastewater treatment and wastewater treatment method |
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