CN102512966A - Reverse osmosis membrane pollution prevention and control method - Google Patents
Reverse osmosis membrane pollution prevention and control method Download PDFInfo
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- CN102512966A CN102512966A CN2011103945790A CN201110394579A CN102512966A CN 102512966 A CN102512966 A CN 102512966A CN 2011103945790 A CN2011103945790 A CN 2011103945790A CN 201110394579 A CN201110394579 A CN 201110394579A CN 102512966 A CN102512966 A CN 102512966A
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Abstract
The invention discloses a reverse osmosis membrane pollution prevention and control method. When the water yield of a reverse osmosis membrane system is lower than 10 percent of the initial water yield or the pressure difference of a reverse osmosis membrane assembly is greater than 0.35MPa, a reverse osmosis membrane is flushed and cleaned through one method or the combination of a plurality of methods of positive membrane surface flushing, reverse membrane surface flushing, positive membrane surface chemical cleaning, reverse membrane surface chemical cleaning, positive gas membrane surface gas cleaning or reverse membrane surface gas cleaning through manual or automatic control, so the water yield of the reverse osmosis membrane system is recovered to more than 99 percent of the initial water yield, and the pressure difference is smaller than 0.25MPa. The reverse osmosis membrane pollution prevention and control method has the advantages that the serious pollution of a rolled reverse osmosis membrane is effectively avoided, and the stable operation of the system is ensured. According to the reverse osmosis membrane pollution prevention and control method, the chemical cleaning frequency of the system can be reduced, the service life of the reverse osmosis membrane is prolonged, and the operation cost of the system is reduced.
Description
Technical field
The present invention relates to method of wastewater treatment, relate in particular to a kind of method of reverse osmosis membrane prevention and cure of pollution.
Background technology
Two embrane methods (ultrafiltration+counter-infiltration) are important method of advanced treatment and reuse of dyeing waste water.The process that reverse osmosis unit produces water is the process that the inorganic ions in the waste water and organic matter are concentrated.General reverse osmosis unit is six cores dresses, and the mode of two sections arrangements promptly is equivalent to 12 film cascades, and therefore the concentration during former water to last consistent membrane module is higher.Therefore the organic matter and the inorganic ions of high concentration are as easy as rolling off a log at this membrane module surface deposition, so the contaminated possibility of film is also maximum, this pollution mainly concentrates on last several membrane components.In addition, two embrane method system generally is provided with pre-processing devices such as air supporting, sand filtration former water is carried out preliminary treatment, could get into two embrane method systems afterwards.If but the influent quality fluctuation is bigger; Particularly water-borne glue body and suspension etc. more very easily cause the runner of reverse osmosis membrane assembly to stop up; At this moment runner stops up and mainly occurs on several the membrane modules of the front in the counter-infiltration system, cause phenomenon be exactly that the pressure reduction of system sharply rises.The consequence that occurs is to cause system's aquifer yield to descend, if long-time running, the pressure differential before and after the reverse osmosis membrane will increase, and make membrane module cause the telescope phenomenon, make the membrane module performance cause expendable damage, thereby cause systemic breakdown.
Summary of the invention
The objective of the invention is to have proposed a kind of method of reverse osmosis membrane prevention and cure of pollution to deficiency of the prior art.
The method of reverse osmosis membrane prevention and cure of pollution is: the pressure reduction of 10% or reverse osmosis membrane assembly that is lower than initial aquifer yield when the reverse osmosis membrane system aquifer yield is during greater than 0.35MPa; Artificial or automatic control; Through one or more combinations in forward flushing membrane surface, back flush film surface, forward Chemical cleaning film surface, reverse Chemical cleaning film surface, forward purge of gas film surface or the reverse purge of gas film surface; Reverse osmosis membrane is washed, cleans; Make the reverse osmosis membrane system aquifer yield return to more than 99% of initial aquifer yield, pressure reduction is less than 0.25MPa.
Described forward flushing membrane surface is that flushing water gets into reverse osmosis membrane system from forward, and the bag filter through water pump and 5 microns washes reverse osmosis membrane system, and intake pressure is less than 0.5MPa, the flow of inlet water 6-8m of single film pipe
3/ h, flushing water returns water tank and recycles.Described back flush film surface be flushing water from reverse entering reverse osmosis membrane system, the bag filter through water pump and 5 microns washes reverse osmosis membrane system, intake pressure is less than 0.5MPa, the flow of inlet water 6-8m of single film pipe
3/ h, flushing water returns water tank and recycles.
Described forward Chemical cleaning film surface is in cleaning water tank, to dispose cleaning agent; Through water pump cleaning agent is got into reverse osmosis membrane system from forward; Bag filter through water pump and 5 microns carries out Chemical cleaning to reverse osmosis membrane system; Intake pressure is less than 0.5MPa, the flow of inlet water 6-8m of single film pipe
3/ h, rinse water is returned water tank and is recycled.Described reverse Chemical cleaning film surface is in cleaning water tank, to dispose cleaning agent; Through water pump with cleaning agent from reverse entering reverse osmosis membrane system; Bag filter through water pump and 5 microns carries out Chemical cleaning to reverse osmosis membrane system; Intake pressure is less than 0.5MPa, the flow of inlet water 6-8m of single film pipe
3/ h, rinse water is returned water tank and is recycled.
Described forward purge of gas film surface is the Compressed Gas through cleaning, gets into reverse osmosis membrane system from forward, and air inlet is pressed less than 0.5MPa.Described reverse purge of gas film surface is the Compressed Gas through cleaning, and from reverse entering reverse osmosis membrane system, air inlet is pressed less than 0.5MPa.
Described reverse osmosis membrane version is rolled structure.
The present invention has thoroughly solved in the dyeing waste water undegradable dyestuff organic matter and a large amount of inorganic ions pollutes reverse osmosis membrane, makes system stable, and operating cost is reduced, and has good economic and social benefit.
Description of drawings
Fig. 1 is a reverse osmosis membrane system flow chart of the present invention.
The specific embodiment
The method of reverse osmosis membrane prevention and cure of pollution is: the pressure reduction of 10% or reverse osmosis membrane assembly that is lower than initial aquifer yield when the reverse osmosis membrane system aquifer yield is during greater than 0.35MPa; Artificial or automatic control; Through one or more combinations in forward flushing membrane surface, back flush film surface, forward Chemical cleaning film surface, reverse Chemical cleaning film surface, forward purge of gas film surface or the reverse purge of gas film surface; Reverse osmosis membrane is washed, cleans; Make the reverse osmosis membrane system aquifer yield return to more than 99% of initial aquifer yield, pressure reduction is less than 0.25MPa.
Described forward flushing membrane surface is that flushing water gets into reverse osmosis membrane system from forward, and the bag filter through water pump and 5 microns washes reverse osmosis membrane system, and intake pressure is less than 0.5MPa, the flow of inlet water 6-8m of single film pipe
3/ h, flushing water returns water tank and recycles.Described back flush film surface be flushing water from reverse entering reverse osmosis membrane system, the bag filter through water pump and 5 microns washes reverse osmosis membrane system, intake pressure is less than 0.5MPa, the flow of inlet water 6-8m of single film pipe
3/ h, flushing water returns water tank and recycles.Washing time 5-30 minute.
Described forward Chemical cleaning film surface is in cleaning water tank, to dispose cleaning agent; Through water pump cleaning agent is got into reverse osmosis membrane system from forward; Bag filter through water pump and 5 microns carries out Chemical cleaning to reverse osmosis membrane system; Intake pressure is less than 0.5MPa, the flow of inlet water 6-8m of single film pipe
3/ h, rinse water is returned water tank and is recycled.Described reverse Chemical cleaning film surface is in cleaning water tank, to dispose cleaning agent; Through water pump with cleaning agent from reverse entering reverse osmosis membrane system; Bag filter through water pump and 5 microns carries out Chemical cleaning to reverse osmosis membrane system; Intake pressure is less than 0.5MPa, the flow of inlet water 6-8m of single film pipe
3/ h, rinse water is returned water tank and is recycled.
Adopt the mode of segmentation to carry out during forward and reverse the cleaning, when promptly carrying out Chemical cleaning to first section, Chemical cleaning can not get into second section yet, prevents that first section pollutant that washes out from getting into second section, pollutes second section assembly.The segmentation chemically-cleaning device is mainly by water pump, water tank, and chemicals dosing plant and corresponding pipe valve are formed, and during Chemical cleaning, can carry out Chemical cleaning respectively, scavenging period 5-30 minute to first section and second section.
Described forward purge of gas film surface is the Compressed Gas through cleaning, gets into reverse osmosis membrane system from forward, and air inlet is pressed less than 0.5MPa.Described reverse purge of gas film surface is the Compressed Gas through cleaning, and from reverse entering reverse osmosis membrane system, air inlet is pressed less than 0.5MPa.
Described reverse osmosis membrane version is rolled structure.
Among Fig. 1: one section forward washes into or one section forward cleans into 1; One section forward air purge advances 2; One section back flush go out or one section oppositely clean out 3; One section back flush advance or one section oppositely clean 4; One section reverse air purge advances 5; One section forward washes out or one section forward cleans out 6; Two sections forwards wash into or two sections forwards clean into 7; Two sections forward air purges advance 8; Two sections back flushes go out or two sections oppositely clean out 9; Two sections back flushes advance or two sections oppositely clean 10; Two sections reverse air purges advance 11; Two sections forwards wash out or two sections forwards clean out 12; Concentrated water discharge valve 13; Water intaking valve 14; Interstage valve 15.
One reverse osmosis unit is divided into two sections arrangements, first section 24 putamina, and second section 18 putamina, two sections are 6 cores dresses, and after operation in several days, aquifer yield is compared when initial and has been reduced by 9%, and the pressure reduction of reverse osmosis membrane assembly reaches 0.40MPa.At first carry out the forward flushing to first section: in water tank, put into the product water of counter-infiltration, open valve 1 and valve 6, open air purge valve 2, the control admission pressure is 0.2MPa, closes other valves, opens water pump, and the flow of control water pump is at 144-192 m
3/ h, intake pressure are 0.3MPa, wash 5-15 minute; Carry out back flush to first section then: in water tank, put into the product water of counter-infiltration, open valve 3 and valve 4, open reverse air purge valve 5, the control admission pressure is 0.2MPa, closes other valves, opens water pump, and the flow of control water pump is at 144-192 m
3/ h, intake pressure are 0.3MPa, wash 5-15 minute; Carry out the forward flushing to second section then: in water tank, put into the product water of counter-infiltration, open valve 7 and valve 12, open air purge valve 8, the control admission pressure is 0.2MPa, closes other valves, opens water pump, and the flow of control water pump is at 108-144 m
3/ h, intake pressure are 0.3MPa, wash 5-15 minute; Carry out back flush to second section then: in water tank, put into the product water of counter-infiltration, open valve 9 and valve 10, open air purge valve 11, the control admission pressure is 0.2MPa, closes other valves, opens water pump, and the flow of control water pump is at 108-144 m
3/ h, intake pressure are 0.3MPa, wash 5-15 minute; Carrying out forward to first section then cleans: in water tank, put into the product water of counter-infiltration, and dispose certain density cleaning agent, open valve 1 and valve 6; Open air purge valve 2, the control admission pressure is 0.2MPa, closes other valves; Open water pump, the flow of control water pump is at 144-192 m
3/ h, intake pressure are 0.3MPa, wash 5-15 minute; Then first section is oppositely cleaned: in water tank, put into the product water of counter-infiltration, and dispose certain density cleaning agent, open valve 3 and valve 4; Open reverse air purge valve 5, the control admission pressure is 0.2MPa, closes other valves; Open water pump, the flow of control water pump is at 144-192 m
3/ h, intake pressure are 0.3MPa, wash 5-15 minute; Carrying out forward to second section then cleans: in water tank, put into the product water of counter-infiltration, and dispose certain density cleaning agent, open valve 7 and valve 12; Open air purge valve 8, the control admission pressure is 0.2MPa, closes other valves; Open water pump, the flow of control water pump is at 108-144 m
3/ h, intake pressure are 0.3MPa, wash 5-15 minute; Then second section is oppositely cleaned: in water tank, put into the product water of counter-infiltration, and dispose certain density cleaning agent, open valve 9 and valve 10; Open air purge valve 11, the control admission pressure is 0.2MPa, closes other valves; Open water pump, the flow of control water pump is at 108-144 m
3/ h, intake pressure are 0.3MPa, wash 5-15 minute; Through above-mentioned cleaning and flushing, it is original more than 99% that the aquifer yield of reverse osmosis membrane reaches, and the pressure reduction of reverse osmosis membrane assembly is reduced to 0.25MPa.
During the real system operation above-mentioned forward flushing, back flush, forward Chemical cleaning; The combination in any of reverse Chemical cleaning and air purge, forward flushing, back flush; The forward Chemical cleaning, reverse Chemical cleaning can combine with the Chemical cleaning of reality, and promptly water pump and water tank are realized shared; The water that is rushed out returns water tank, can be recycled, and has improved the rate of recovery of system.In addition, can control, realize the automatic switchover of valve, thereby realize control automatically by PLC.
At last, what need particularly point out is that what more than to enumerate only is practical implementation case of the present invention.Obviously, the invention is not restricted to above-mentioned case study on implementation, can also many combinations.The all scenario that those of ordinary skill in the art can directly derive or associate from content disclosed by the invention all should be thought protection scope of the present invention.
Claims (8)
1. the method for reverse osmosis membrane prevention and cure of pollution; It is characterized in that: the pressure reduction of 10% or reverse osmosis membrane assembly that is lower than initial aquifer yield when the reverse osmosis membrane system aquifer yield is during greater than 0.35MPa; Artificial or automatic control; Through one or more combinations in forward flushing membrane surface, back flush film surface, forward Chemical cleaning film surface, reverse Chemical cleaning film surface, forward purge of gas film surface or the reverse purge of gas film surface; Reverse osmosis membrane is washed, cleans, make the reverse osmosis membrane system aquifer yield return to more than 99% of initial aquifer yield, pressure reduction is less than 0.25MPa.
2. the method for a kind of reverse osmosis membrane prevention and cure of pollution according to claim 1; It is characterized in that described forward flushing membrane surface is that flushing water gets into reverse osmosis membrane system from forward; Bag filter through water pump and 5 microns washes reverse osmosis membrane system; Intake pressure is less than 0.5MPa, the flow of inlet water 6-8m3/h of single film pipe, and flushing water returns water tank and recycles.
3. the method for a kind of reverse osmosis membrane prevention and cure of pollution according to claim 1; It is characterized in that described back flush film surface is that flushing water is from reverse entering reverse osmosis membrane system; Bag filter through water pump and 5 microns washes reverse osmosis membrane system; Intake pressure is less than 0.5MPa, the flow of inlet water 6-8m of single film pipe
3/ h, flushing water returns water tank and recycles.
4. the method for a kind of reverse osmosis membrane prevention and cure of pollution according to claim 1; It is characterized in that described forward Chemical cleaning film surface is in cleaning water tank, to dispose cleaning agent; Through water pump cleaning agent is got into reverse osmosis membrane system from forward; Bag filter through water pump and 5 microns carries out Chemical cleaning to reverse osmosis membrane system, and intake pressure is less than 0.5MPa, the flow of inlet water 6-8m of single film pipe
3/ h, rinse water is returned water tank and is recycled.
5. the method for a kind of reverse osmosis membrane prevention and cure of pollution according to claim 1; It is characterized in that described reverse Chemical cleaning film surface is in cleaning water tank, to dispose cleaning agent; Through water pump with cleaning agent from reverse entering reverse osmosis membrane system; Bag filter through water pump and 5 microns carries out Chemical cleaning to reverse osmosis membrane system, and intake pressure is less than 0.5MPa, the flow of inlet water 6-8m of single film pipe
3/ h, rinse water is returned water tank and is recycled.
6. the method for a kind of reverse osmosis membrane prevention and cure of pollution according to claim 1 is characterized in that described forward purge of gas film surface is the Compressed Gas through cleaning, gets into reverse osmosis membrane system from forward, and air inlet is pressed less than 0.5MPa.
7. the method for a kind of reverse osmosis membrane prevention and cure of pollution according to claim 1 is characterized in that described reverse purge of gas film surface is the Compressed Gas through cleaning, and from reverse entering reverse osmosis membrane system, air inlet is pressed less than 0.5MPa.
8. the method for a kind of reverse osmosis membrane prevention and cure of pollution according to claim 1 is characterized in that described reverse osmosis membrane version is rolled structure.
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| Application Number | Priority Date | Filing Date | Title |
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| CN2011103945790A CN102512966A (en) | 2011-12-02 | 2011-12-02 | Reverse osmosis membrane pollution prevention and control method |
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| CN2011103945790A CN102512966A (en) | 2011-12-02 | 2011-12-02 | Reverse osmosis membrane pollution prevention and control method |
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| CN104211136A (en) * | 2014-10-14 | 2014-12-17 | 厦门绿创科技有限公司 | Full-automatic control nanofiltration membrane online strong flushing method |
| CN105597549A (en) * | 2016-02-14 | 2016-05-25 | 大唐内蒙古多伦煤化工有限责任公司 | Device and method for cleaning nanofiltration membrane |
| CN108310834A (en) * | 2017-01-18 | 2018-07-24 | 黄学锋 | Three-level backwashing system and purging method |
| CN114074967A (en) * | 2020-08-12 | 2022-02-22 | 云米互联科技(广东)有限公司 | Household water purifying device |
| CN115228298A (en) * | 2022-07-19 | 2022-10-25 | 金科环境股份有限公司 | Rolled membrane system and gas-liquid two-phase cleaning method thereof |
| CN115970499A (en) * | 2023-03-20 | 2023-04-18 | 金科环境股份有限公司 | Reverse osmosis system control method and device, electronic equipment and storage medium |
| CN115999376A (en) * | 2023-03-20 | 2023-04-25 | 金科环境股份有限公司 | Reverse osmosis membrane cleaning method and device, electronic equipment and storage medium |
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| CN104211136A (en) * | 2014-10-14 | 2014-12-17 | 厦门绿创科技有限公司 | Full-automatic control nanofiltration membrane online strong flushing method |
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| CN115999376A (en) * | 2023-03-20 | 2023-04-25 | 金科环境股份有限公司 | Reverse osmosis membrane cleaning method and device, electronic equipment and storage medium |
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Application publication date: 20120627 |