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49results about How to "Efficient removal rate" patented technology

Chitosan composite gel water purifying agent and preparation method thereof

The invention discloses a chitosan composite gel water purifying agent, which is gel prepared from solution of chitosan, cellulose, silica gel and activated carbon according to the mass ratio of 1:1-2.5:2-3.5:3-5. The invention also discloses a method for preparing the chitosan composite gel water purifying agent, which comprises the following steps of: adding the cellulose, the silica gel and the activated carbon into the solution of chitosan in turn; fully stirring at a high speed until black and homogeneous semifluid gel is formed, and obtaining the chitosan composite gel water purifying agent. The water purifying agent is natural and nontoxic, has functions of high-efficiency adsorption and flocculation, can be used for deep purification of an underwater environment polluted by endocrine disruptors and also can be used for emergency treatment in public health water pollution emergency. Meanwhile, the preparation method makes operation simple, reduces cost and is environmentally-friendly and suitable for industrial production.
Owner:ZHEJIANG ACAD OF MEDICAL SCI

Non-Newtonian fluid thickening polishing method and polishing system based on magnetic field assist

ActiveCN109079590AUniform distribution of magnetic field strengthImprove processing efficiencyEngineeringUltra precision
The invention discloses a non-Newtonian fluid thickening polishing method based on a magnetic field assist. The method comprises the following steps: S1: adding non-Newtonian fluid polishing liquid with magnetorheological properties into a polishing liquid tank, and immersing a polishing workpiece in the non-Newtonian fluid polishing liquid through a holding device with a driving system, and turning on a magnetic field generating device; S2: under the action of the driving system, driving the polishing workpiece to rotate by the holding device, enabling the polishing workpiece and the non-Newtonian fluid polishing liquid to move relative to each other, and cutting the surface of the polished workpiece by abrasive grains in the non-Newtonian fluid polishing liquid, thereby completing the polishing process. The invention further correspondingly provides a non-Newtonian fluid thickening polishing system based on the magnetic field assist. The non-Newtonian fluid thickening polishing method provided by the invention is low in consumables cost, high in polishing efficiency and good in polishing effect, and can realize ultra-precision polishing of the polished workpiece.
Owner:HUNAN UNIV

Two-phase two-period anaerobic organism reactor for processing wastewater

The invention discloses a two-phase tow-period anaerobic organism reactor processing wastewater. The reactor comprises a reactor body, a circulation tank, an alkali adding device, a biological phase separator, a primary three-phase separator and a secondary three-phase separator, wherein the circulation water tank and the alkali adding device are arranged on the outer side of the reactor body, and the biological phase separator, the primary three-phase separator and the secondary three-phase separator are arranged in the reactor body from bottom to top, a closed acidification reaction chamberis arranged at the lower part of the reactor body, and the biological phase separator is arranged at the top in the acidification reaction chamber; a methane-generating main reaction area is formed between the upper part of the acidification reaction chamber and the primary three-phase separator, and a methane-generating fine processing area is formed between the primary three-phase separator andthe secondary three-phase separator. The anaerobic organism reactor provided by the invention has the advantages that the structure is compact, the occupying area is small, the organic load reaches to 40kg COD (chemical oxygen demand) / (m<3>.d) when the reactor is used for processing high-concentration wastewater generated by pulping and paper making or similar wastewater, and the stability and the flexibility are extremely high when the reactor is used for processing wastewater with variable water quantity and water quality.
Owner:SOUTH CHINA UNIV OF TECH +1

Technology for treating organic wastewater by means of efficient anaerobic reactor

ActiveCN106430567AExternal circulation design system is stableSmall footprintWater treatment compoundsWater contaminantsHigh concentrationAnaerobic reactor
The invention provides a technology for treating organic wastewater by means of an efficient anaerobic reactor. The technology comprises the following steps of 1 water charging, 2 treating conducted in a front pre-reactor, 3 material feeding, 4 treating conducted in a main reactor, 5 water discharging, 6 biogas collecting and 7 sludge collecting. According to the technology, efficient anaerobic treatment is conducted on the high-concentration organic wastewater by adopting the technology of combining the front pre-reactor with the anaerobic main reactor, therefore, the removal rate of COD in effluent is higher than 92%, and the working efficiency of the technology is greatly improved.
Owner:江苏中金环保科技有限公司

Bacterial cellulose membrane/porous carbon adsorbent and preparation thereof

The invention discloses a bacterial cellulose membrane / porous carbon adsorbent and preparation thereof. The bacterial cellulose membrane / porous carbon adsorbent is prepared by taking a bacterial cellulose membrane as a matrix, taking different saccharides as carbon sources and using a hydrothermal carbonization method; due to the anchoring function of a large number of hydroxyls on the surface of the bacterial cellulose, the porous carbon can be preferably dispersed in the bacterial cellulose membrane and different nano pore diameters can be obtained by adjusting the growth process of the bacterial cellulose membrane. The adsorbent combines the filtration of the nano pore diameters of the membrane and the adsorption of the porous carbon, is used for adsorbing and dispelling PM2.5 smoke and poisonous gas and has the advantages f being environmentally friendly and high in efficiency.
Owner:NANJING UNIV OF SCI & TECH +1

Method for recycling sludge

The invention discloses a method for recycling sludge, comprising the following steps of: mixing the sludge with Ca(OH)2, placing the mixture into an fermentation reactor and stirring and performing anaerobic fermentation; discharging a certain volume of fermentation mixture from the reactor at regular time intervals, and adding fresh sludge in the same amount as the discharged mixture and a certain amount of Ca(OH)2; and adding a FeSO4 solution into the discharged mixture, stirred for a certain time, adding a polyacrylamide solution, stirring for a certain time, and then carrying out filter pressing for dewatering. The method remarkably improves the concentration and the fermentation liquor amount of short chain fatty acid generated by the sludge, decreases the volatile substances of the sludge, and meanwhile, can remove most phosphate in the fermentation liquor.
Owner:TONGJI UNIV

Gas-liquid-solid three-phase abrasive flow plane polishing system based on cavitation effect

The invention discloses a gas-liquid-solid three-phase abrasive flow plane polishing system based on a cavitation effect, comprising a two-degree-of-freedom moving device, a gas-liquid-solid mixing device, a rotary driving device, a cavitation polishing tool, a workpiece clamping device, a workpiece processing pool, an abrasive flow circulation device, a high-pressure gas injection device and a console, wherein the cavitation polishing tool comprises an outer constraint block and an inner constraint block which jointly form an annular narrow-slit flow channel with a large inlet and a small outlet; and the annular narrow-slit flow channel communicates with a through hole in a rotary spindle through an internal flow channel in an outer constraint body. The gas-liquid-solid three-phase abrasive flow plane polishing system based on a cavitation effect uses the principle of structural cavitation to set the annular narrow-slit flow channel on a cavitation polishing tool, and realizes the structural cavitation of the liquid by using a flow channel design with a larger inlet and a smaller outlet, and realizes the high-efficient material removal rate of the workpiece surface; and the liquidsecondary cavitation is realized by the design of a round corner on the cavitation polishing tool, so that the efficiency of fluid polishing is improved.
Owner:ZHEJIANG UNIV OF TECH

Modified active carbon and preparation method application thereof

The invention provides a modified active carbon and a preparation method application thereof. The method comprises the following steps of: placing active carbon into a quartz pipe of a muffle furnace; filling nitrogen in the muffle furnace at room temperature for 1-2 hours, wherein the gas flow rate is 80-120ml / min; then heating the muffle furnace to 400-800 DEG C at the speed of 10 DEG C / min under the protection of the same nitrogen flow and maintaining for 1-4 hours; after the temperature is reduced to 25 DEG C, stopping filling the nitrogen; continuously filling air at the flow rate of 80-120ml / min for 1hour and taking out to obtain the modified active carbon. The modified active carbon is used as an adsorbent and used for removing organic pollutants in the process of water treatment, has the advantages of high purifying ability and long service life and particularly can solve the problem of poor maneuverability on high-concentration phenol endocrine distributing object polluted water by the traditional water treatment method.
Owner:HARBIN ENG UNIV

Copper-based metal organic framework material immobilized laccase as well as preparation method and application thereof

The invention relates to the field of environmental protection, and particularly discloses copper-based metal organic framework material immobilized laccase as well as a preparation method and application thereof. The preparation method comprises the following steps of dissolving copper acetate and laccase in water to prepare a solution A; dissolving a p-aminobenzoic acid solution into an acetic acid buffer solution to prepare a solution B, then mixing the two solutions, and performing stirring for 4 hours or above; and centrifugally collecting solid, performing washing with water, and performing freeze-drying to obtain the copper-based metal organic framework material immobilized laccase. According to the method, the copper-based MOF (Cu-PABA) immobilized laccase is adopted for the firsttime, a coprecipitation method is used for one-step synthesis, the method is faster and more environmentally friendly, the stability of the laccase is greatly improved, and the laccase can be recycledfor eight times or above after bisphenol A is degraded. After the laccase is immobilized, 41.7% of the activity can be retained. The copper-based metal organic framework material immobilized laccaseprovided by the invention has good bisphenol A removal capability, and the bisphenol A removal rate in 12 hours can reach about 80% in the presence of ABTS.
Owner:SOUTH CHINA UNIV OF TECH +1

Method for treating sewage by using artificial wetland

ActiveCN103395949ASolve the problem of blockage and difficult maintenanceSmall footprintMultistage water/sewage treatmentConstructed wetlandSelf recovery
The invention belongs to artificial wetland utilization, especially to a method for treating sewage by using artificial wetland. The method mainly adopts sewage pretreatment, sewage aeration treatment, sewage purification and other process steps. With the present invention, problems of easy clogging, poor self-recovery capability and the like of the wetland in the prior art are solved, and the method has advantages of reasonable process design, clogging resistance of the wetland system, good pollutant removing effect, strong self-recovery capability, and the like.
Owner:北京中环达生态科技有限公司

Salt-resistant denitrifying bacterium and application thereof

The invention discloses a salt-resistant denitrifying bacterium and application thereof, relates to the technical field of environment microorganisms and aims to solve the technical problems that the denitrogenation capability of a conventional common denitrifying bacterium is limited by a high salt degree and nitrite nitrogen in salt-containing breeding wastewater cannot be removed. The bacterium is Alishewanella sp.F2, is preserved in the China General Microbiological Culture Collection Center, the preservation date is March 25, 2019, and the preservation number is CGMCC No: 17433. The bacterium is capable of implementing denitrogenation and denitrification under a salt-containing condition. The bacterium disclosed by the invention is adopted to remove nitrite nitrogen pollutants in a water body.
Owner:NORTHEAST INST OF GEOGRAPHY & AGRIECOLOGY C A S

Magnetic composite functional material for high efficiency removal of Congo red in water and preparation method thereof

The invention discloses a magnetic composite functional material with both adsorption and flocculation effects for high efficiency removal of Congo red in water and a preparation method thereof, and belongs to the technical field of dye wastewater treatment. The magnetic composite functional material is prepared by compounding three components of sepiolite, Fe3O4 and cetyl trimethyl ammonium bromide (CTAB). The preparation method is as follows: purified sepiolite is thermally modified, a bivalent and trivalent iron ion mixed solution is added for magnetic modification, and a cetyl trimethyl ammonium bromide (CTAB) solution is added for organic modification to obtain organically-modified magnetic sepiolite, namely the magnetic composite functional material. The preparation method has the advantages of low cost, simple operation and strong operability. The magnetic composite functional material is applied to the treatment of Congo red model wastewater, the concentration range is 100-4500mg / L, under the optimized conditions, the maximum removal capacity of the Congo red is 4478.92mg / g, and the removal rate is 96.49%-99.92%.
Owner:XIANGTAN UNIV

Thick oil-degrading bacteria and application thereof

InactiveCN101921722AEfficient heavy oil removal rateGood environmental adaptabilityWaste water treatment from quariesBacteriaCoccobacillusObligate aerobe
The invention discloses thick oil-degrading bacteria and application thereof. The bacterial strain is Acinetobacter sp. GS02 collected by China Center for Type Culture Collection on July 8, 2010, with the collection number of CCTCC M 2010172. The bacterial colony of the bacteria is round, has smooth protrusions and neat edges, is off-white and has viscosity. The bacteria are sporeless coccobacillus when observed under an electron microscope. The bacteria have the biological characteristics of oxidase negative, catalase positive, gram stain negative, no fermentation and obligate aerobe. The bacterial strain has good effect of removing alkane components, nonbiodegradable pristine and phytane in thick oil, and has high-efficiency thick oil removal rate and good adaptive capacity to environment compared with other bacterial strains. Based on the characteristics, the bacteria can be well applied to the restoration of thick oil-polluted water and soil.
Owner:SOUTH CHINA UNIV OF TECH

CuPc-at-Ti3C2TxMXene catalytic material, electrode and application of CuPc-at-Ti3C2TxMXene catalytic material and electrode in nitrate radical reduction

The invention discloses a CuPc-at-Ti3C2Tx MXene catalytic material, an electrode preparation method thereof and application of the CuPc-at-Ti3C2Tx MXene catalytic material in nitrate reduction ammoniaproduction. The method comprises the steps: obtaining the CuPc-at-Ti3C2Tx MXene catalytic material by mixing a CuPc ethanol solution and a Ti3C2Tx MXene solution, centrifugally washing and drying precipitates; and then loading the CuPc-at-Ti3C2Tx MXene catalytic material on the hydrophilic surface of carbon cloth to obtain the electrode for producing ammonia by electrocatalytic reduction of nitrate, which is used for producing ammonia by electrocatalytic reduction of nitrate. An electrode prepared from the CuPc-at-Ti3C2Tx Mxene composite material disclosed by the invention has the characteristics of good cycling stability and high electrochemical activity.
Owner:SUZHOU UNIV

Waste water nitrogen and phosphorus removal apparatus and waste water treatment method

The invention discloses a waste water nitrogen and phosphorus removal apparatus and a waste water treatment method, which belongs to the field of sewage treatment. The waste water nitrogen and phosphorus removal apparatus comprises a denitrification column filled with sawdust and a phosphorus filtering column filled with acidic mine drainage residues. The sawdust denitrification column is coupledwith the acidic drainage residue phosphorus filter columns, the heterotrophism-autrophism denitrification nitrogen removal technology and biology-chemical phosphorus removal technology are integrated,the nitrogen and phosphorus removal treatment is performed for the point-source breeding waste water comprising nitrogen and phosphorus and scattered agricultural floor tile discharged water, and a purpose of efficiently purifying the water can be achieved. The waste water nitrogen and phposphorus removal apparatus has the advantages of simple structure, reasonable design, small floor occupationarea, low material cost and significant purification effect.
Owner:NANJING INST OF ENVIRONMENTAL SCI MINIST OF ECOLOGY & ENVIRONMENT OF THE PEOPLES REPUBLIC OF CHINA

Novel polyvinyl chloride (PVC) mother solution treatment equipment and method

The invention discloses novel polyvinyl chloride (PVC) mother solution treatment method. The PVC mother solution is passed through a primary cooling and a secondary cooling to an anaerobic pool and an aerobiotic pool to apply biochemical treatment, then the product is put into a coagulating sedimentation pool to settle the sludge, at last, the product is filtered by submerged ultrafiltration, so as to produce the qualified water. The novel PVC mother solution treatment equipment has a good water treatment effect and high operating stability, can be used for effectively treating the PVC mother solution for a long time, and is relatively low in operating cost and high in quality of output water.
Owner:INNER MONGOLIA WUHAI CHEM IND

Microbial sewage treating agent for deep synergistic purification of sewage and preparation method

The invention provides a microbial sewage treating agent for deep synergistic purification of sewage and a preparation method. Anaerobic digestive bacteria-silicone colloidal particles are formed by anaerobic digestive bacteria, seaweed nutrients, silicone and a dispersing agent through mixing and granulation, meanwhile, high molecular weight polyethylene and porous ceramic powder are mixed and ground, then, denitrifying bacteria are added, a denitrifying bacterium premix is obtained, an inorganic adhesive is sprayed to the surfaces of anaerobic digestive bacteria-silicone colloidal particles,the anaerobic digestive bacteria-silicone colloidal particles covered with the inorganic adhesive and the denitrifying bacterium premix are rolled and mixed, granulation and pelletizing are performed, and the microbial sewage treating agent for deep synergistic purification of sewage is obtained. According to the method, the anaerobic digestive bacteria are immobilized through silicone and covered with a denitrifying bacterium premix film, the defect that denitrifying bacteria and anaerobic digestive bacteria have difficulty in playing a role in sewage is overcome, the removal process is simple, the removal efficiency is high, the preparation and use cost is low, and large-scale popularization and application can be realized.
Owner:CHENDU NEW KELI CHEM SCI CO LTD

Device and method for treatment and recovery of nitrogen and phosphorus in wastewater by utilizing seawater desalination concentrate

The invention provides a device and a method for treatment and recovery of nitrogen and phosphorus in wastewater by utilizing a seawater desalination concentrate. The device comprises a housing, wherein an inclined plate settling device and a clear water outlet are arranged at the upper part of the housing, a water inlet pipe is arranged at the lower part of the housing, a diversion plate for segmenting a housing channel into a diversion area and a circulation area is arranged in the housing, a baffle plate is arranged above the diversion area, a sedimentation area is arranged above the baffle plate, an outlet of the water inlet pipe is opposite to the bottom of the diversion area, an inlet of the water inlet pipe is connected with sewage and the concentrated wastewater produced by desalination of seawater, a sludge hopper and a sludge discharge pipe are arranged at the bottom of the housing, and a first circulation pump is arranged between the sludge discharge pipe and the water inlet pipe. The invention relates to the device and the method for nitrogen removal, phosphorus removal and recovery of the nitrogen and the phosphorus by taking a technology of using the concentrated wastewater produced by desalination of the seawater and reutilizing the reaction with phosphate ions to generate magnesium ammonium phosphate and hydroxyapatite crystals to achieve the recovery of the nitrogen and the phosphorus as the core, so that the treatment problem of the concentrated wastewater produced by a seawater desalination device can be solved, and the waste of resources and energy consumption can be further reduced.
Owner:HARBIN ENG UNIV

Method for removing organic dyestuff in wastewater

The invention discloses a method for removing organic dyestuff in wastewater. The method adopts a magnetic gel ball adsorption material to adsorb the organic dyestuff in the wastewater, and removes the organic dyestuff by mixing and oscillating the magnetic adsorption material and the wastewater or enabling the wastewater to flow through an adsorption column of the magnetic adsorption material to remove the organic dyestuff in the wastewater. The magnetic adsorption material has the advantages of realization of efficient removal of organic dyes in wastewater, reduction of the pollution of the organic dyes in water, provision of a new approach for solving the problem of water pollution, realization of the easy separation and recycling of the magnetic adsorption material and recycling, and the adsorbed dye can be removed in an acid environment, the dye is enriched and recovered, the recovered dye can be reused in production after being purified, and the pollution of the dye is reduced.
Owner:SHAANXI UNIV OF SCI & TECH

Biological membrane used for waste gas treatment, and preparation method of biological membrane

The invention provides a biological membrane used for waste gas treatment, and a preparation method of the biological membrane, and in particular relates to the technical field of waste gas purification. According to the preparation method, biotrickling filter filler is obtained by using formic acid to perform catalytic polymerization on polylactic acid and polyvinyl alcohol, and the biological membrane used for the waste gas treatment is prepared by inoculating the filler with nutrient mud and spraying the filler with a nutrient solution. The biological membrane prepared by the method has good compatibility with the filler, and can stably adhere to the filler, so that the fixation time is shortened to 3h at most; the biological membrane has a high removal rate for refractory pollutants; after the biological membrane is used, the removal rate of organic matters in industrial waste gas is 90% or above, the removal rate of 1, 4-dioxane is 94% or above, and the removal rate of dioxin is 92% or above. The invention also provides the preparation method of the biological membrane; the method is stable and controllable, and is easy to implement, thus being suitable for large-scale production.
Owner:广西霸普环保科技有限公司

Method for quickly predicting removal rate of spiral curved surface grinding material

The invention relates to a rapid prediction method for the removal rate of a spiral curved surface grinding material, and the method comprises the following steps: carrying out the grinding of the concave surface of a screw rotor in a contact wheel type abrasive belt grinding mode according to the characteristics of the molded surface of the screw rotor, and obtaining the stress distribution p'ofa contact region; machining the convex surface of the screw rotor in a free abrasive belt grinding mode to obtain contact area stress distribution p ''; combining p'and p '' with abrasive belt grinding process parameters, applying a ThunderGBM regression prediction algorithm to obtain prediction model functions; and finally obtaining the material removal rate of the surface of the screw rotor. According to the method, the removal rate of the abrasive belt grinding material of the screw rotor can be efficiently and quickly predicted, so that the machining efficiency is improved on the premise of uniformly removing spiral curved surface parts.
Owner:SHENYANG POLYTECHNIC UNIV

Treatment process of cutting fluid wastewater

The invention discloses a cutting fluid treatment process, which mainly comprises the following steps: adding sodium hydroxide to adjust the pH value to 7.6-8.5, adding a demulsifier to carry out demulsification, and carrying out oil-water separation ultrafiltration membrane separation on the wastewater after the demulsification is completed; adding the supernatant into a photocatalysis tank, andcarrying out photocatalytic membrane dynamic catalytic treatment to obtain a treatment solution; and adding the salt scale corrosion inhibitor into the treatment solution, and conveying to a concentration device for cyclic distillation to remove the salt solution to obtain a distillate. By limiting the molar ratio of the preparation raw materials, limiting the weight ratio of the compound demulsifier and functionally modifying TiO2, the cutting fluid treatment process with an excellent decontamination effect is researched, has extremely high COD removal rate and oil removal rate on cutting fluid wastewater, is suitable for being popularized and used as a cutting fluid treatment process in the field of water treatment, and has a wide development prospect.
Owner:伸荣(上海)水处理环保工程有限公司

Efficient method for treating acidic iron-containing wastewater generated by waste coal mine

The invention provides an efficient method for treating acidic iron-containing wastewater generated by a waste coal mine. Portland cement or common Portland cement is used as a main treatment agent raw material and added into coal mine acidic iron-containing wastewater, and bentonite and coal ash can be doped into a treatment agent, wherein addineffg amount of the treatment agent in the coal mineacidic iron-containing wastewater is 0-2.0%; well mixing, aeration reaction and standing treatment are performed after adding. The efficient method is good in treatment effect and high in pollutant removal rate. The method has remarkable treatment effect on the coal mine acidic iron-containing wastewater and especially can efficiently remove iron and manganese in the wastewater. After the wastewater is treated by the method, removal rate of iron in the wastewater can reach higher than 99%, removal rate of manganese can reach higher than 95%, and other indexes meet national and local water quality emission standards. The treatment agent is low in cost, simple in process and high in efficiency, and the method is economically affordable and does not cause secondary pollution.
Owner:SICHUAN UNIV

A Salt-tolerant Denitrifying Bacteria and Its Application

A salt-tolerant denitrifying bacterium and its application, the invention relates to the technical field of environmental microorganisms. The invention aims to solve the technical problem that the nitrogen removal ability of the existing common denitrifying bacteria is inhibited by high salinity and cannot remove the nitrite nitrogen in the saline culture wastewater. The strain is Alishewanella sp.F2, which was deposited in the General Microbiology Center of the China Committee for the Collection of Microbial Cultures. The preservation date was March 25, 2019. The number is CGMCC No: 17433. The strain can denitrify and denitrify under saline conditions. The bacterial strain of the invention is used for removing nitrite nitrogen pollutants in water bodies.
Owner:NORTHEAST INST OF GEOGRAPHY & AGRIECOLOGY C A S

A bacterial cellulose membrane/porous carbon adsorbent and its preparation

The invention discloses a bacterial cellulose membrane / porous carbon adsorbent and its preparation. The adsorbent uses bacterial cellulose membrane as a substrate, and different sugars as carbon sources. The bacterial cellulose membrane / porous carbon adsorbent is prepared by hydrothermal carbonization. Due to the anchoring effect of a large number of hydroxyl groups on the surface of bacterial cellulose, the porous carbon It can be better dispersed in the bacterial fiber membrane, and at the same time, different sizes of nanopores can be obtained by adjusting the growth process of the cellulose membrane. The adsorbent of the present invention combines the dual functions of membrane nano-pore filtration and porous carbon adsorption, and is used to adsorb and remove PM2.5 smoke dust and toxic gases. The adsorbent has the advantages of environmental protection and high efficiency.
Owner:NANJING UNIV OF SCI & TECH +1
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