CN207552098U - The device that CO2 puies forward the high yield water rate of recovery is added in a kind of membrane filtration - Google Patents

Abstract

The utility model discloses add CO in a kind of membrane filtration₂Carry the device of the high yield water rate of recovery, it is equipped with along water inlet direction and is made up of intake pool, booster pump, pretreatment filtration system, intermediate water tank, NF/RO membrane components and sedimentation basin that pipeline is connected successively, wherein pretreatment filtration system be micro-filtration filter, ultrafilter or more medium filter, the air inlet and CO on intermediate water tank top₂The air outlet pipe of closed add-on system is tightly connected, NF/RO membrane components are arranged in parallel in one or more levels formula arranged in series or in one or more snippets formula, NF films or RO films use rolling or hollow fiber composite membrane, heating unit is equipped in sedimentation basin, supernatant in sedimentation basin is mixed into pretreatment filtration system by pipeline reflux and booster pump water outlet, and the precipitated liquid in sedimentation basin passes through discharge of pipes.The utility model technique main body and corollary equipment are compact-sized, multiple functional, and easily operated repair, arrangement mode can be with flexible combination.

Description

CO is added in a kind of membrane filtration2Carry the device of the high yield water rate of recovery

Technical field

The utility model belongs to water-saving and emission-reducing technical field, and in particular to adds CO in a kind of membrane filtration₂High yield water is put forward to return The device of yield.

Background technology

Nanofiltration（NF）Film and reverse osmosis（RO）Film can have in water treatment procedure according to its pore size and stalling characteristic Organic matter, algae, bacterium, pathogenic microorganism, inorganic colloid particle, heavy metal ion, nitric acid and Asia in the removal feedwater of effect ground The pollutants such as nitrate, but should have such as fouling membrane important bottleneck problem low with the production water rate of recovery in the process.NF film conducts One novel membrane separation technique, pore diameter range is between RO films and ultrafiltration membrane, and NF films itself are with charge（It is logical Often show as bear electricity）, have higher removing between the organic matter of 200-1000kDa to divalent and multivalent ion and molecular weight Effect.At present, main NF separation mechanism of membrane has Screening theory, adsorption theory, dissolving-diffusion theory and electrical charge rejection theory Deng.RO films can stop all dissolubility salt and molecular weight is more than the organic matter of 100Da, but hydrone is allowed to penetrate, and extensively should For in brackish water desalination and sea water desalination, main separating mechanism include dissolving-diffusion, Preferential adsorption-pore stream it is theoretical and Hydrogen bond theory etc..NF films and RO films are all pressure drive membranes, and concentrated water and production water are separated under the effect of outer add operation pressure.

In NF films and RO membrane separating process, the recycling efficiency of producing water be often it is relatively low and limited, this mainly by It is formed on the durometer compound inorganic scale to be formed, such as Ca²⁺、Si²⁺、Ba²⁺、Mg²⁺Wait bivalent cations and CO₃ ^2-、SO₄ ^2-Etc. divalent it is cloudy Ion inorganic pollution caused by film surface forms precipitation due to concentration polarization etc.；The microorganisms such as bacterium, algae are in film table Face forms group, while their secretion can also promote other organic matters to be adhered to film surface and then form film, finally lead Cause more serious fouling membrane；Organic pollution is by the interaction with film, so as to be adsorbed in film surface and block fenestra, into one Step makes NF flux depressions, and operating cost rises.During NF films and RO film purified waters, the rate of recovery for producing water is typically in the range of Between 40%-75%, the rate of recovery is depended primarily on into water physical property and NF concentrated water reuse amount.At the same time, a large amount of concentrated water is discharged into environment Terminal can be caused to make sharply increasing for water cost.

Therefore, selection rationally effective pretreating process and optimize technique design, can effectively prevent or mitigate fouling membrane, prolong The service life of long film puies forward the high yield water rate of recovery.Before NF films and RO membrane filtrations, series of preprocessing technique include micro-filtration, Ultrafiltration, ion exchange, degassing and adjustment pH value etc.；Or the side such as advanced treating is carried out for the concentrated water after NF films and RO membrane filtrations Method can effectively improve the production water rate of recovery of NF films and RO films.So exist during NF films and RO water treatment by membrane at present Concentrated water yield is big, the production water rate of recovery is low, does not meet the puzzlement of the industries such as clean manufacturing, in order to ensure the sustainable development of industry, grinds For hair on the basis of ensureing to produce water quality, it is extremely important to effectively improve NF concentrated water reuse technology to mitigate the method for fouling membrane simultaneously 's.Using pretreatment before NF films and RO membrane filtrations and concentrated water precipitation reuse after filtering（By adding CO₂And NaHCO₃Adjust solution PH value, and then remove the hardness number of solution in sedimentation basin）Hydridization coupling operation process, can greatly improve the production water rate of recovery, It reduces environmental pollution and increases economic efficiency.In NF films and the processing of RO film waters or field of water pollution control, relevant data-searching Less than related addition CO₂Carry the patent report of the high yield water rate of recovery.The patent of publication number CN 101774731A discloses one kind and subtracts Enhanced coagulation-air lift-film the integral method and device of light fouling membrane, add coagulant, flocculation aid and gas stripping type in raw water Aerator not only alleviates fouling membrane, saves membrane module operation energy consumption, extends the membrane module cycle of operation, reduces cost of investment, It is easy to implement flexibly.But the stripping step of this patented technology only relates to the aerating step of processing unit, it is intended to flow be driven to exist It is recycled and is disturbed in membrane module, formed shear flow in film surface, the blocking of fenestra is reduced, so as to alleviate fouling membrane；Film The concentrated water that separation generates is not further processed, so as to cause water resource waste, inadequate economical and effective.Publication number CN The patent of 106186550A discloses a kind of sewage recycling Zero emission device and method, realizes dominant cation, the moon in feedwater Whole recycling of ion and the recycling of sludge, but by adding a large amount of highly acid during the patent technology implementation Medicament adjusts the pH value of solution, and then leads to the corrosion of subsequent pipeline, and operating cost is caused to improve, exist simultaneously device it is complicated and The shortcomings of taking up a large area.

Invention content

The purpose of this utility model is that it is low and simultaneously to solve the production water rate of recovery in existing NF films and RO membrane separating process It the problem of reduction or decelerating membrane pollution, provides in a kind of membrane filtration and adds CO₂The device of the high yield water rate of recovery is carried, was both improved Water resource makes water cost using horizontal can reduce again, the hydridization coupling technique being combined using pretreatment+membrane filtration+sedimentation basin Technology makes the system production water rate of recovery be up to more than 90%, so that the effectively amount of conserving water, realizes the regeneration of concentrated water, this technique Main body and corollary equipment are compact-sized, multiple functional, and easily operated repair, arrangement mode can be with flexible combination.

The utility model adopts the following technical scheme that solve above-mentioned technical problem, and CO is added in a kind of membrane filtration₂It improves The method for producing the water rate of recovery, it is characterised in that the specific steps are：

（1）Pending brine waste is sucked and is stored in intake pool as water inlet solution for later use；

（2）Enter pretreatment filtration system into aqueous solution under the action of booster pump, preprocessed filtration system remove into During the preprocessing solution generated after colloid, suspended particulate substance, bacterial micro-organism and macromolecule organic matter in aqueous solution enters Between water tank；

（3）Pass through CO₂Closed add-on system injects CO to intermediate water tank₂To adjust the pH value of solution in intermediate water tank, make pH Value be reduced to 8.32 hereinafter, and add antisludging agent generation bicarbonate breadth coefficient dramatically increase, carbonate breadth coefficient it is notable The condition solution of decline；

（4）Condition solution is sunk into NF/RO membrane components, by NF/RO membrane components treated production water be collected processing, By NF/RO membrane components, treated that concentrated water is reacted in the sedimentation basin of built-in heating unit, and supernatant is generated after standing clarification And precipitated liquid, circulating and recovering supernatant are mixed into pretreatment filtration system, precipitated liquid discharge system, film mistake with booster pump water outlet The filter production water rate of recovery reaches 80%-95%.

Further preferably, the pretreatment filtration system is micro-filtration filter, ultrafilter or more medium filter, is somebody's turn to do Pretreatment filtration system has for effectively removing into colloid, suspended particulate substance, bacterial micro-organism and the macromolecule in aqueous solution Machine object.

Further preferably, in the intermediate water tank solution by adding CO₂The pH value of adjusting film water inlet is reduced to 4.55- 8.32, carbonate breadth coefficient is remarkably decreased to 1.15% hereinafter, preventing from generating in NF films or RO film surfaces by adding antisludging agent Precipitation is polyacrylic acid, EDTA, acrylic acid or acid/maleic acid copolymers with decelerating membrane pollution, wherein antisludging agent.

Further preferably, water inlet pH value of the NF/RO membrane components water inlet pH value control for 4.55-8.32, wherein RO films In 7.50-8.50, salt rejection rate reaches highest, and according to producing water water quality needs, NF/RO membrane components are in one or more levels formula series connection row Row are arranged in parallel in one or more snippets formula, and the NF films or RO films use rolling or hollow fiber composite membrane.

Further preferably, by successively into sedimentation basin after the NF/RO membrane components treated concentrated water enters sedimentation basin Addition precipitating reagent, flocculation aid and flocculant are reacted, and wherein precipitating reagent is CaCO₃And CaSO₄Powder, flocculation aid are aluminum sulfate Or iron chloride, flocculant are polyacrylic acid and the alkaline hydrolysis object or acrylic acid of polyacrylamide and the copolymer of acrylamide. Add a small amount of precipitating reagent such as CaCO₃And CaSO₄Powder can quickly generating with role's induced precipitation of nucleus；Flocculation aid and The addition of flocculant can act on the grain size for dramatically increasing depositing particles by chemical bonding, so as to which sedimentation basin liquid be accelerated to consolidate The separation of two-phase；Inorganic or organic polymer flocculation aid can be formed by electric double layer pinch effect and Electrostatic Absorption effect Large-sized precipitation flco etc.；And on this basis, flocculant further functions as physical bind-mechanism effect.Due to inorganic There is certain compatibility between cation and Flokal B, anionic flocculant is generally more desirable, such as polyacrylic acid And the alkaline hydrolysis object or acrylic acid of polyacrylamide and the copolymers such as acrylamide.

Further preferably, the solution in the sedimentation basin adjusts pH value to 10.0-11.5 by adding aqueous slkali, thus It is co-precipitated in sedimentation basin, wherein Ba²⁺、Fe³⁺、Mn²⁺And Al³⁺It is removed in corresponding low-level, Ca²⁺With CaCO₃And CaSO₄ Form removal, SiO₂Or silicate is removed in the form of Si-Ca-Mg compound precipitations.

CO is added in membrane filtration described in the utility model₂Carry the device of the high yield water rate of recovery, it is characterised in that along water inlet Direction be equipped with successively the intake pool being connected by pipeline, booster pump, pretreatment filtration system, intermediate water tank, NF/RO membrane components and Sedimentation basin is formed, and wherein pretreatment filtration system is micro-filtration filter, ultrafilter or more medium filter, on intermediate water tank The air inlet and CO in portion₂The air outlet pipe of closed add-on system is tightly connected, and NF/RO membrane components are in one or more levels formula arranged in series Or be arranged in parallel in one or more snippets formula, using rolling or hollow fiber composite membrane, sedimentation basin is interior to be equipped with heating for NF films or RO films Device, supernatant in sedimentation basin are mixed into pretreatment filtration system by pipeline reflux and booster pump water outlet, in sedimentation basin Precipitated liquid pass through discharge of pipes.

Further preferably, the NF/RO membrane components are the NF membrane elements being arranged in parallel in two-stage type arranged in series or two-part Part or RO membrane components.

Pass through CO in the utility model₂Filling can reduce in NF/RO membrane component surface scales, compared to using H₂SO₄Or HCl adjusts pH value, CO₂Usual not corrosion pipeline and equipment, it does not need to store as acid solution.CO₂It is mainly used to adjust solution PH value simultaneously provides generation bicarbonate in sedimentation basin, for next effectively removing for hardness is prepared in sedimentation basin.It compares With other sour de-regulation solution ph, CO is added₂Show more effectively low cost and environment friendly.

The utility model is by filling CO₂If adjusting solution ph is reduced to 8.32 hereinafter, filled in open system, CO₂Air, inadequate economical and efficient may be escaped into, so CO will be completed in closed system₂It adds and correspondingly increases simultaneously System pressure, pressure increase will drive reaction equation（1）It moves to the right, pH value is allowed to drop to required level.CO₂It can also It injects in the closed conduct between sedimentation basin and membrane filter unit, by reducing solution ph and also providing simultaneously sufficient concentrations of Heavy carbonate () and carbonate (), it prepares for sufficient precipitation reaction occurs in sedimentation basin.

（1）

Heating unit in the sedimentation basin can increase CO₂Removal effect, NF films and RO film concentrated waters enter sedimentation basin Remove hardness and CO₂, the mode of operation that heating or decompression or both are carried out at the same time, principle such as reaction equation may be used（2）It is shown, Above-mentioned condition will be more effectively HCO₃ ^-It is changed into CO₃ ^2-And CO₂, and CO₂It can volatilize and collect to recycle profit after escaping With, while the demand for increasing pH value in sedimentation basin to adding alkali number can also be reduced.

（2）

The raising system production water rate of recovery refers to that for example the NF/RO membrane components production water rate of recovery is 80%, if used CO is added in membrane filtration₂Device, in pond to be precipitated after solid-liquid separation, then supernatant fluid reuse rate is 10%, then NF/RO membrane elements The system production water rate of recovery of part can further be promoted to 90%.The increase of the system production water rate of recovery in the device, it is heavy to depend on Hardness effectively removes degree in the pond of shallow lake.

The utility model has following apparent advantageous characteristic compared with traditional brine waste treatment process and device：

1st, compared with traditional handicraft and device, the system production water rate of recovery can be made to increase to 80%-95% from 40%-75%, together When correspondingly reduce dense salt wastewater treatment capacity and processing cost；Add CO₂To film filter, solution ph can be significantly reduced And bicarbonate is provided in sedimentation basin, it prepares subsequently to effectively remove hardness in sedimentation basin；

2nd, CO is completed in closed system₂It adds and correspondingly increases system pressure simultaneously, pressure increase will drive automatically CO₂Dissolving and the generation of bicarbonate, allow pH value to drop to required level automatically；

3、CO₂Then recycling and secondary use can be collected by heating and depressurizing, so as to reduce the pollution to environment, Compared to using H₂SO₄Or HCl adjusts pH value, CO₂Filling can not only reduce fouling in film surface, but also the technology is stale-proof Lose pipeline and equipment, it is not required that acid solution stores；

4th, the utility model device is simple in structure, and the rate of recovery of system production water is high, and floor space is small, extends the Membrane cleaning period Mitigate cost, this technology has considerable economic benefit and environmental benefit.

Description of the drawings

Fig. 1 is that NF/RO membrane components are arranged in parallel in membrane filtration processes in two-part and add CO₂Raising system produces the water rate of recovery Process flow chart；

Fig. 2 is that NF/RO membrane components are in add CO in two-stage type arranged in series membrane filtration processes₂Raising system produces the water rate of recovery Process flow chart.

In figure：1st, intake pool, 2, booster pump, 3, ultrafilter, 31, micro-filtration filter, 4, intermediate water tank, 5, CO₂It is close Close add-on system, 6, one sections of NF/RO membrane components, 61, level-one NF/RO membrane components, 7, two sections of NF/RO membrane components, 71, two level NF/ RO membrane components, 8, sedimentation basin, 9, heating unit.

Specific embodiment

The above of the utility model is described in further detail by the following examples, but this should not be understood Range for the above-mentioned theme of the utility model is only limitted to following embodiment, all skills realized based on the utility model the above Art belongs to the scope of the utility model.The utility model is described in detail by way of example and in conjunction with the accompanying drawings.

With reference to attached drawing 1-2, CO is added in the membrane filtration processes of the utility model₂Raising system produces the device of the water rate of recovery, Fig. 1 includes intake pool 1, booster pump 2, ultrafilter 3, intermediate water tank 4, CO₂Closed 5, one sections of NF/RO film groups of add-on system 6, two sections of NF/RO membrane modules 7 of part, sedimentation basin 8 and heating unit 9, the outlet of intake pool 1 are connect with the import of booster pump 2, supercharging The outlet of pump 2 is connect with the import of ultrafilter 3, and the outlet of ultrafilter 3 is connect with the import of intermediate water tank 4, CO₂It is close It closes the air outlet pipe of add-on system 5 to be tightly connected with the air inlet of intermediate water tank 4, the outlet of intermediate water tank 4 and one section of NF/RO membrane element The import connection of part 6, one section of NF/RO membrane component 6 generate one section of NF/RO films production water, one section of NF/RO films production water and two sections of NF/RO The import connection of membrane component 7, two sections of NF/RO membrane components 7 generate two sections of NF/RO films production water, two sections of NF/RO films concentrated water outlets and one Import of the section NF/RO films concentrated water outlet respectively with sedimentation basin 8 is connect, quiet after the heated device 9 of the solution in sedimentation basin 8 heats It puts clarification a period of time, a part of supernatant in sedimentation basin 8 is back to ultrafilter 3, a part of precipitated liquid by pipeline It is discharged by pipeline.

Fig. 2 includes intake pool 1, booster pump 2, micro-filtration filter 31, intermediate water tank 4, CO₂Closed add-on system 5, level-one NF/RO membrane components 61, two level NF/RO membrane components 71, sedimentation basin 8 and heating unit 9, the outlet of intake pool 1 and booster pump 2 into Mouth connection, the outlet of booster pump 2 are connect with the import of micro-filtration filter 31, outlet and the intermediate water tank 4 of micro-filtration filter 31 Import connects, CO₂The air outlet pipe of closed add-on system 5 is tightly connected with the air inlet of intermediate water tank 4, the outlet of intermediate water tank 4 Import with level-one NF/RO membrane components 61 is connect, and level-one NF/RO membrane components 61 generate level-one NF/RO films production water, level-one NF/RO Film production water is connect with the import of two level NF/RO membrane components 71, and two level NF/RO membrane components 71 generate two level NF/RO films production water, two level 61 concentrated water of NF/RO membrane components exports the import exported with 71 concentrated water of level-one NF/RO membrane components respectively with sedimentation basin 8 and connect, and precipitates After the heated device 9 of solution heats in pond 8, clarification a period of time is stood, a part of supernatant in sedimentation basin 8 is back to micro-filtration Filter 31, a part of precipitated liquid are discharged by pipeline.

Embodiment 1

As shown in Figure 1, the higher brine waste of concentration in intake pool is directly sunk ultrafilter by booster pump, lead to Hyperfiltration technique removal suspended solid, colloid and some larger molecular organics are crossed, pretreated production water enters intermediate water tank, closed Add CO₂PH value is reduced to 7.55, while adds in antisludging agent acid/maleic acid copolymers, prevents film surface fouling, the condition solution Water is produced by the RO films that one section of RO membrane component generates and enters two sections of RO membrane components, carry out the two level RO films after advanced treating produce water into Row is collected, wherein the production water rate of recovery of two sections of RO membrane components reaches 60%；Two sections of RO films concentrated waters mix laggard with one section of RO film concentrated water Enter sedimentation basin, flocculation aid and flocculant aluminum sulfate, polyacrylic acid are added in sedimentation basin, for increasing the particle size of sediment With acceleration separation of solid and liquid process, it is 11.0 that alkali is added, which to adjust sedimentation basin solution ph, is co-precipitated, some ions such as Ba²⁺、Fe^{3 +}、Mn²⁺、Al³⁺Dozens of or tens ppm, the CO of addition can be reduced to Deng the concentration in sedimentation basin solution₂It can make Ca²⁺From Son is with CaCO₃And CaSO₄Form removal, SiO₂Or silicate is removed in the form of Si-Ca-Mg compound precipitations, passes through heating It can be more effectively by HCO₃ ^-It is changed into CO₃ ^2-And CO₂, therefore CO₂Can volatilize effusion, escape the CO of system₂It is used for after collection Recycling and secondary use, while sedimentation basin solution adds alkali to increasing amount needed for pH value can also be reduced.It is raw in sedimentation basin Into supernatant combined with water inlet after carry out circular treatment, be 24% so as to additionally increase the production water rate of recovery so that system production water returns Yield is up to 84% and without film surface scaling fouling risk.

Embodiment 2

As shown in Fig. 2, the relatively low brine waste of concentration in intake pool is intake sinks micro-filtration filter by booster pump, lead to The removal such as micro-filter technology or multimedium sand coarse aggregate ratio suspended solid, colloid and some larger molecular organics are crossed, in pretreated solution Inject CO₂PH is adjusted to 6.58, while add in antiscale HEDP to prevent film surface fouling, which passes through level-one NF membrane components Level-one NF films production water is generated, level-one NF film concentrated waters enter two level NF membrane components generation second segment NF film production water, two-stage NF membrane components The production water rate of recovery for 75%, two level NF film concentrated waters enter sedimentation basin, and flocculation aid and flocculant are added in sedimentation basin（Tri-chlorination Iron and acrylamide copolymer）Increase the particle size of sediment and accelerate separation of solid and liquid, alkali is added to adjust pH value of solution in sedimentation basin It is 11.5 to be worth, and is co-precipitated, some ions such as Ba²⁺、Fe³⁺、Mn²⁺、Al³⁺Concentration of the plasma in sedimentation basin solution can drop Down to dozens of or tens ppm, the CO of addition₂It can make Ca²⁺With CaCO₃And CaSO₄Form removal, SiO₂Or silicate It is removed in the form of Si-Ca-Mg compound precipitations, it can be more effectively by HCO by decompression₃ ^-It is changed into CO₃ ^2-And CO₂, therefore CO₂Can volatilize effusion, escape the CO of system₂Then recycling can be collected, while can also be reduced in sedimentation basin solution To increasing pH value to the required required amount for adding alkali.The supernatant generated in sedimentation basin carries out circular treatment after being combined with water inlet, Be 16.8% so as to additionally increase the production water rate of recovery so that the system production water rate of recovery be up to 91.7% and without film surface scaling fouling wind Danger.

The basic principle of the utility model, main feature and advantage has been shown and described above, it is new not departing from this practicality Under the premise of type spirit and scope, the utility model also has various changes and modifications, these changes and improvements both fall within requirement and protect The scope of the utility model of shield.

Claims (2)

1. add CO in a kind of membrane filtration₂Carry the device of the high yield water rate of recovery, it is characterised in that：It is equipped with successively along water inlet direction logical Intake pool, booster pump, pretreatment filtration system, intermediate water tank, NF/RO membrane components and the sedimentation basin that piping is connected are formed, Middle pretreatment filtration system be micro-filtration filter, ultrafilter or more medium filter, the air inlet on intermediate water tank top with CO₂The air outlet pipe of closed add-on system is tightly connected, and NF/RO membrane components are in one or more levels formula arranged in series or in one section or more Segmentation is arranged in parallel, and NF films or RO films are equipped with heating unit using rolling or hollow fiber composite membrane in sedimentation basin, in sedimentation basin Supernatant pretreatment filtration system is mixed by pipeline reflux and booster pump water outlet, the precipitated liquid in sedimentation basin passes through pipe It discharges in road.

2. add CO in membrane filtration according to claim 1₂Carry the device of the high yield water rate of recovery, it is characterised in that：It is described NF/RO membrane components are the NF membrane components or RO membrane components being arranged in parallel in two-stage type arranged in series or two-part.