Search

CN-121648747-B - Low-damage efficient cleaning agent formula for MBR (Membrane bioreactor)

CN121648747BCN 121648747 BCN121648747 BCN 121648747BCN-121648747-B

Abstract

The invention discloses a low-damage efficient cleaning agent formula for an MBR (membrane bioreactor) in the field of water treatment chemistry, which comprises three functional materials, namely trinuclear iron-zirconium-silicon hybridized hydroxy phosphate, layered bimetallic hydroxy cerium nitrate molybdate and nano cage-shaped titanium-tungsten-borosilicate, and is compounded with sodium citrate, polyepoxysuccinic acid, sodium dodecyl benzene sulfonate, sodium percarbonate, borax and deionized water. The three core materials are synthesized by a specific coprecipitation and sol-gel method, a constant pH coprecipitation method and a template-assisted sol-gel combined calcination method respectively. According to the formula, through the synergistic effect of the components, the efficient complexing, adsorption, dispersion and mild oxidation stripping of the organic, inorganic and biological composite pollution layers on the membrane surface are realized, and meanwhile, due to the nearly neutral mild cleaning environment and the low corrosion characteristic of the material, the chemical damage to the membrane material can be obviously reduced, the membrane flux is effectively recovered, and the service life of the membrane is prolonged.

Inventors

  • DING LEI
  • Diao Siyuan
  • LI JIA
  • LIU HAIYUAN
  • WANG ZHU
  • XIE JUN

Assignees

  • 湖南湘新碧水源环境科技有限公司

Dates

Publication Date
20260505
Application Date
20260202

Claims (7)

  1. 1. The low-damage efficient cleaning agent for the MBR membrane bioreactor is characterized by comprising the following raw materials in parts by weight: 3-6 parts by weight of trinuclear iron-zirconium-silicon hybridized hydroxy phosphate; 2-5 parts by weight of layered bimetallic cerium hydroxy nitrate molybdate; 1.5 to 4 weight portions of nano cage titanium-tungsten-borosilicate; 5-10 parts by weight of sodium citrate; 2-6 parts by weight of polyepoxysuccinic acid; 0.5-2 parts by weight of sodium dodecyl benzene sulfonate; 8-15 parts of sodium percarbonate; 1-3 parts of borax; 45-80 parts of deionized water; The preparation method of the trinuclear iron-zirconium-silicon hybrid hydroxy phosphate comprises the steps of A1, sequentially adding ferric chloride hexahydrate, zirconium oxychloride octahydrate and ethyl orthosilicate into deionized water, stirring under the protection of nitrogen, dropwise adding an aqueous solution of sodium dihydrogen phosphate, regulating the pH value to 6.6-7.0 after dropwise adding, heating to 84-86 ℃ and stirring for reaction, A2, naturally cooling to room temperature after the reaction is finished, centrifugally separating and precipitating, washing the precipitate with deionized water and absolute ethyl alcohol, drying in vacuum at 58-62 ℃, and grinding; The preparation method of the layered bimetal cerium nitrate hydroxy molybdate comprises the steps of B1, respectively dissolving cerium nitrate hexahydrate and sodium molybdate dihydrate in deionized water to respectively obtain cerium salt solution and molybdate solution, dropwise adding the cerium salt solution and the molybdate solution into dilute nitric acid solution with pH value of 5.4-5.6 under the stirring condition to obtain colloid, B2, transferring the colloid into 88-92 ℃ oil bath for ageing, cooling and suction filtering to obtain a solid product, washing the solid product with dilute nitric acid with pH value of 5.4-5.6, washing the solid product with deionized water to be neutral, and vacuum drying at 58-62 ℃; The preparation method of the nano cage-shaped titanium-tungsten-borosilicate comprises the steps of C1, dropwise adding titanium tetrachloride into absolute ethyl alcohol under ice bath, introducing nitrogen to obtain a titanium alcohol solution, adding tetraethoxysilane into the titanium alcohol solution, stirring to obtain a titanium-silicon alcohol mixed solution, dissolving ammonium metatungstate and boric acid in deionized water, heating to 58-62 ℃ to obtain a boron tungsten solution, adding the boron tungsten solution into the titanium-silicon alcohol mixed solution, stirring, then adding cetyl trimethyl ammonium bromide to obtain the mixed solution, carrying out reflux reaction on the mixed solution at 78-82 ℃, cooling the reaction solution, centrifuging to obtain a precipitate, washing the precipitate with the ethanol-water mixed solution, and calcining in a 545-555 ℃ muffle furnace.
  2. 2. The low-damage high-efficiency cleaning agent for MBR membrane bioreactor as recited in claim 1, wherein in the step A1, the reaction time of stirring after the temperature is raised to 84-86 ℃ is 12-14h.
  3. 3. The low-damage high-efficiency detergent for MBR membrane bioreactor according to claim 1, wherein in the step A2, the time of vacuum drying at 58-62 ℃ is 12-14h.
  4. 4. The low-damage high-efficiency detergent for MBR membrane bioreactor as claimed in claim 1, wherein in the step B1, the stirring time is 30-60min.
  5. 5. The low-damage high-efficiency detergent for MBR membrane bioreactor according to claim 1, wherein in the step B2, the time of vacuum drying at 58-62 ℃ is 10-12h.
  6. 6. The low-damage high-efficiency cleaning agent for MBR membrane bioreactor as recited in claim 1, wherein in the step C1, the mixed solution is subjected to reflux reaction at 78-82 ℃ for 24-30 hours.
  7. 7. The low damage high efficiency cleaning agent for MBR membrane bioreactor of claim 1, wherein in step C2, the calcination time in a 545-555 ℃ muffle furnace is 4-6h.

Description

Low-damage efficient cleaning agent formula for MBR (Membrane bioreactor) Technical Field The invention belongs to the technical field of water treatment chemistry, and particularly relates to a low-damage efficient cleaning agent formula for an MBR (Membrane bioreactor). Background Membrane bioreactors are widely used in municipal and industrial fields as a key technology for modern wastewater treatment, but their operational stability is often severely challenged by high suspended matter water. When treating raw water with a large amount of sand, the open channel transport process results in a large amount of particulate matter entering the system, causing rapid blockage of the interior of the membrane modules. These particles not only physically embed into the membrane filament interstices, but also promote excessive secretion of extracellular polymers in anaerobic microenvironment, forming a highly viscous fouling layer. Particularly troublesome, the anaerobic condition becomes an ideal breeding temperature bed for the midge larvae (commonly called red worms), and the biological film covers the surface of the film to further block the water flow channel. The traditional cleaning mode is difficult to simultaneously cope with biological pollution blocking, organic adhesion and inorganic scaling combined pollution, so that the membrane flux is rapidly reduced, the system operation period is forced to be shortened, and the treatment efficiency and the water outlet stability are seriously restricted. Current industry cleaning practices have significant drawbacks. On-line cleaning generally depends on sodium hypochlorite solution, although organic matters can be partially oxidized, the on-line cleaning has weak effect on killing red worms, and high-concentration chloride ions accelerate the oxidative degradation of the membrane material. The off-line cleaning adopts a combined scheme of oxalic acid soaking and sodium hypochlorite treatment, and the oxalic acid can dissolve part of inorganic scale, but the strong acidity of the oxalic acid can cause irreversible corrosion to polyvinylidene fluoride membrane filaments, and the service life of the membrane is greatly shortened by repeated use. Meanwhile, oxalic acid treatment cannot effectively decompose sand particles, but rather aggravates membrane wire abrasion due to mechanical scouring. More importantly, the existing medicament lacks of targeted control on biological fouling, and the red worms have short breeding cycle and quick regeneration, so that the pollution quickly recurs after cleaning. Frequent offline cleaning (more than twice a year) not only increases labor and equipment loss, but also causes long-time shutdown of the system, large fluctuation of water production flow, incapability of realizing continuous and stable operation, and obvious increase of economic and technical costs. The present invention arose from the urgent need for efficient low damage cleaning techniques. Three inorganic modified compounds are innovatively designed to cooperatively realize multiple-effect functions of biological inhibition, dirt depolymerization and particle dispersion. The cleaning agent can accurately kill the midge larvae bred in anaerobic environment and block biological pollution circulation, has a unique structure, can effectively depolymerize the extracellular polymer adhesive layer, reduces film surface adhesion, simultaneously dissolves inorganic scaling such as calcium and magnesium, and wraps tiny sand particles to prevent film wires from being scratched. In practical application, the membrane flux can be obviously recovered only by on-line circulation treatment, and frequent interruption of off-line cleaning is avoided. The integrated solution not only prolongs the service life of the membrane component, but also improves the overall operation efficiency of the system by reducing the maintenance frequency, thereby providing a sustainable clean technical path for high-suspended-matter wastewater treatment and effectively solving the long-term membrane pollution chronic diseases in the industry. Disclosure of Invention Aiming at the defects of the prior art, the invention aims to provide a low-damage efficient cleaning agent formula for an MBR (membrane bioreactor). In a first aspect of the invention, a low-damage high-efficiency cleaning agent formula for an MBR membrane bioreactor is provided, which comprises the following raw materials in parts by weight: 3-6 parts by weight of trinuclear iron-zirconium-silicon hybridized hydroxy phosphate; 2-5 parts by weight of layered bimetallic cerium hydroxy nitrate molybdate; 1.5 to 4 weight portions of nano cage titanium-tungsten-borosilicate; 5-10 parts by weight of sodium citrate; 2-6 parts by weight of polyepoxysuccinic acid; 0.5-2 parts by weight of sodium dodecyl benzene sulfonate; 8-15 parts of sodium percarbonate; 1-3 parts of borax; 45-80 parts of deionized water. In the invention, each component in