287 results about "Anaerobic wastewater treatment" patented technology

The invention relates to a coal chemical wastewater treating technique, which comprises the following steps of: pretreating the coal chemical wastewater by an air-floatation device and obtaining pretreated wastewater; adding a fenton reagent into the pretreated wastewater to carry out secondarily treatment and obtaining secondarily treated wastewater; putting the secondarily treated wastewater into an activated sludge aeration pool and adding active carbon powder into the pool for deep treatment to obtain deeply treated wastewater; separating the deeply treated wastewater with a hyperfiltration membrane and obtaining separated recycled water; reversely penetrating the separated recycled water with a selective semi-permeable membrane and obtaining reversely penetrated recycled water; evaporating and crystallizing the reversely penetrated recycled water and finishing the wastewater treatment. The wastewater, after treated by the coal chemical wastewater treating technique, can realize the 'zero discharge' standard, meet the national environmental requirements, and obtain good economic and social benefits.

This invention relates to a refuse landfill leachate wastewater treatment system comprising a collection well, an adjustment tank, a filter, a comprehensive treatment system having a multi-stage anoxic / aerobic pool and a membrane biological reactor. The process of treatment is: waste water enters a adjustment tanke in which water quality and quantity are adjusted; subsequently, enters a filter, the water discharged from the filter and enters a comprehensive treatment system having a multi-stage anoxic / aerobic pool and a membrane biological reactor, wherein waster water is bio-chemically treated to remove the organic substances, nitrogen and ammonia, and then the wastewater is discharged into a catalyzed oxidation tower; the organic substance in waste water is oxidized on effect of ozone and under the existing catalyst function and then the biochemical capacity thereof is enhanced; and then the catalyzed and oxidized waste water enters carbon filter pool, the remaining contaminated matter can be further removed by degradation of the anoxic oxidation of the biological membrane on the packing material in pool, then the output water meets the requirement of National Standard or other relevant industrial standards.

The invention discloses a preparation method of a nanometer Fe(0)-porous sludge carbon material. The method includes: taking iron salt as an iron source of nanometer Fe(0), taking sludge as a precursor for thermal reduction of porous carbon and iron salt, taking an organic matter capable of generating a great quantity of gas by thermal decomposition at 300-500 DEG C as a pore forming agent, taking waste organics as a carbon regulating agent (in order to solve the problem of difference of organic carbon composition of sludge different in source), taking water as a harmonizing agent, and performing pyrolysis carbonization and thermal reduction at 500-900 DEG C to obtain the nanometer Fe(0)-porous sludge carbon material being 0.01-100micron in pore diameter, wherein Fe(0) average particle size is 30-80mm. The nanometer Fe(0)-porous sludge carbon material is effective in dechlorination and toxicity reduction and has a promising application prospect in various environmental pollution control fields including dehalogenation reduction, soil remediation, heavy metal wastewater treatment, printing and dyeing wastewater treatment and / or anaerobic wastewater treatment and the like, and sludge recycling and 'using waste to treat waste' are realized.

The invention discloses a method for processing dye wastewater, comprising the following steps of: injecting dye wastewater which undergoes a pretreatment into a nanofiltration water inflow tank for nanofiltration to form a nanofiltration concentrated solution with a smaller volume and a nanofiltration dialysate with a larger volume; diluting the nanofiltration concentrated solution to decrease the salt content and then carrying out an anaerobic-aerobic treatment; and carrying out an activated carbon adsorption treatment on the nanofiltration dialysate. In allusion to the features of high salt content and high COD concentration in the dye wastewater, the pretreatment is performed at the front end to reduce part of COD loads, and the nanofiltration technology is adopted at the back end to separate the salt in sewage from organic matters; the concentrated solution with high concentration of organic matters is diluted to reduce COD, simultaneously decrease the salt content and carry out the anaerobic-aerobic biochemical process so as to complete the processing of the sewage. As it is tested that the COD of the dialysate is low, the dialysate undergoes the activated carbon adsorption to directly discharge salts; absorbed organic matters undergo activated carbon desorption and regeneration process as well as biodegradation. The part of wastewater has been desalinized, thus not influencing the biochemical process.

The invention relates to the technical field of wastewater treatment and particularly discloses a treatment method of organic wastewater. The treatment method comprises steps as follows: the organic wastewater and ozone enter a reactor for a reaction, and the reactor is sequentially filled with a catalyst A and a catalyst B according to the contact sequence with the organic wastewater. The methodadopts a simple process, is good in stability and high in COD removal capability and can solve the problem about metal loss.

The invention provides a system and a method for municipal wastewater treatment through continuous flow step-feed water partial nitrification / anaerobic ammonia oxidation, and belongs to the field of biological sewage treatment. The system comprises a raw water tank, a continuous flow step-feed water partial nitrification / anaerobic ammonia oxidation reactor, an on-line monitoring and feedback system and a vertical-flow type precipitation tank; activated sludge and a biological membrane are combined, partial nitrification is realized in activated sludge, and anaerobic ammonia oxidation is realized in the biological membrane, so that the sludge age ratio contradiction between partial nitrification and anaerobic ammonia oxidation is solved, the stability is enhanced and the efficiency is improved; the on-line monitoring and the feedback system is used for dissolved oxygen control in an aerobic stage, and hydraulic retention time real-time control is combined, so that problems that stabilization maintenance in a continuous flow partial nitrification process is difficult and half partial nitrification cannot be realized are solved; an alternate aerobic or anoxic operation is applied to a continuous flow system to inhibit nitrite-oxidizing bacteria; raw water is fed into all of anoxic stages in a segmental manner, and a silicon source in the raw water is utilized to realize denitrification, so that a problem of nitrate nitrogen is solved.

Complete equipment for stainless steel pickling wastewater treatment and resource recycling and a treatment process are disclosed. A pretreatment section, a membrane treatment section and a quality-based crystallization section are involved. The invention is characterized in that a storage regulating basin, a neutralization-oxidation reaction tank, a flocculent precipitation tank, a filter, an ultrafiltration and reverse osmosis system, a membrane concentration system and an evaporation and concentration and quality-based crystallization system are mutually connected end to end through pipelines. Each dosage device is respectively arranged on corresponding section. According to the order of the pretreatment section, the membrane treatment section and the quality-based crystallization section, thirteen steps are included for the operation. By the treatment process of chemical reactive precipitation, membrane separation concentration and evaporation and quality-based crystallization, various acid wastewaters mainly containing acid and inorganic salt can be treated to realize recycling of wastewater. After crystallization of salt, sodium sulfate (and sodium chloride), sodium nitrate, sodium fluoride and other products can be recycled, and zero-discharge resource utilization of stainless steel pickling wastewater is realized. Meanwhile, system sludge yield is greatly reduced such that the burden of sludge treatment is decreased.

A machine and methods using electro-chemical treatments, sedimentation processes and dissolved air flotation technologies for clarification of several kind of wastewater produced in industries, sewages, ponds, lakes, canals etc. The machine comprises of, feeding lines with multiple feeding point, a tank and further a collection tank. The wastewater is passed into the feeding line which may comprises of several feeding points for coagulants, flocculants, and other chemicals dosing into the flow of wastewater and may also comprises of a static mixer for mixing the coagulants, flocculants, and other chemicals with wastewater to agglomerate any solid particles and to accelerate separation of the solid particles in the tank. Once the solid are formed, they can go up or down, therefore to remove the suspended solids the outlet are rearranged depending on the suspended solids. Further, the machine is used for treatment of wastewater utilising multi pass concept to produce clean water.

The invention discloses a method for treating organic chemical wastewater having high COD (chemical oxygen demand) and high concentration of sulfate ions. The method mainly comprises the following steps of: Ca(OH)2 pre-treatment; anaerobic treatment; two-stage aerobic treatment and the like, wherein after the organic chemical wastewater is subjected to Ca(OH)2 pre-treatment to remove most of sulfate ions and H<+> (hydrogen ions), a method for wastewater anaerobic treatment, which takes the advantages of anaerobic bacteria, and a method for wastewater aerobic treatment, which is mainly based on halophilic aerobic microorganisms, can be formed by controlling the microorganisms as the main agent for wastewater treatment and the operating parameter factors. Therefore, the invention is particularly suitable for the treatment of organic chemical wastewater having high COD, high concentration of sulfate ions and low pH value.

The invention discloses a wastewater treatment and recycling technology based UV photocatalytic oxidation. The method comprises the following steps: a, detecting the COD value of waste water with a potassium dichromate method; b, determining the amount of catalyst and UV irradiation time according to the COD value of wastewater; c, adding the catalyst, evenly mixing the catalyst with wastewater; d, introducing air or ozone; e, introducing into a UV photocatalytic oxidation reaction device, and irradiating by ultraviolet; f, detecting the COD value of the liquid; if the COD value is lower than the emission standard, entering to the step g, and if the COD value is higher than the emission standard, returning to the step for re-reaction; and g, adjusting the pH value within 6 to 9; and h. discharging the treated wastewater. The technology provided by the invention makes pollutants completely harmless, and realizes more significant decomposition effect and the bulk chemical wastewater treatment of high concentration COD. The technology has the advantages of wide application range, no secondary pollution, green, environment-friendliness, and low cost of processing equipment.

A wastewater treatment apparatus (1) of the present invention is provided with: an oxidation treatment means (20) for oxidizing a metal complex-forming compound contained in wastewater (W0) that contains at least a heavy metal and the metal complex-forming compound; an insolubilization treatment means (30) for insolubilizing the heavy metal in the oxidized wastewater (W0); and a membrane separation means (40) for separating the insolubilized wastewater (W0) through a membrane. In addition, a wastewater treatment method of the present invention uses the above-described wastewater treatment apparatus. The present invention is capable of providing a wastewater treatment apparatus, a wastewater treatment method and a wastewater treatment system, each of which is capable of highly treating wastewater that contains a heavy metal and a metal complex-forming compound without adding a flocculant to the wastewater, and each of which is capable of sufficiently decreasing the heavy metal concentration.

The invention discloses a phenol-amine wastewater treatment and recycling method and device. The device comprises a water collection tank, a primary settling tank, an adjusting tank, a stripping and ammonia absorption system, an A / A / O-the MBR reaction tank, a biochar hydrolysis, nitrification and fluidization system and an immersed ultrafiltration system which are connected in series according tothe flow of the wastewater treatment. The device of the invention adopts the method combining the main physicochemical technology and the auxiliary biochemical technology, thus effectively reducing the operating cost, wherein the physicochemical technology is mainly used to reduce the concentration of ammonia nitrogen, remove suspended matter (SS) and insoluble, slightly soluble and refractory CODcr and increase the B / C ratio; and the biochemical technology is mainly used to remove CODcr and BOD5 and reduce the chroma. The device of the invention has very good treatment effect on the wastewater with high ammonia nitrogen and high phenolic compounds; and the treated wastewater meets the discharge standards and can be directly discharged or further treated for reuse, thus saving the energy.

The invention belongs to the technical field of wastewater treatment, and discloses a cassava alcohol wastewater biological treatment technology. The technology comprises the following steps: distilling wastewater, filtering distilled wastewater through a sand basin to remove silt and cassava residues, treating under stirring and aerating conditions for 5-6h, and adjusting the pH value to 6-6.5; carrying out primary anaerobic treatment at 58-62DEG C, screening, carrying out secondary anaerobic treatment at 38-42DEG C, allowing obtained wastewater to enter a membrane bioreactor, and carrying out nitrogen removal treatment and mud-water separation; allowing separated wastewater to enter an aerobic tank, and carrying out aerobic treatment; and carrying out advanced treatment on outlet water through a nanofiltration device, or adding a water purifier and powdery active carbon and treating through a down-flow continuous fixed bed in order to obtain standard meeting discharged water or reuse water. The technology has the advantages of simplicity, good treatment effect, low comprehensive cost, and realization of harmony and unification of environment benefits and economic benefits.

The invention relates to the technical field of water paint wastewater treatment, in particular to a water paint production wastewater retreatment method. The method includes: step one, adding wastewater into a wastewater settling tank, adding polyaluminium chloride which is 0.1-0.3%. of the wastewater in weight, and starting an air pump for blowing and mixing for 20-40 minutes; and step two, after floating particulate matters in the wastewater are stable, slowly adding polyacrylamide solution with the weight being 0.25-0.75% of that of the wastewater and the concentration being 0.5-1.5%. to enable the floating particulate matters in the wastewater to be completely flocculated and the water to be clear. The wastewater is subjected to chemical flocculating settling, mechanical filtering and disinfection and then reused for production after water quality is qualified, the separated sludge can be subjected to drying and grinding and then used for production of construction putty powder, and accordingly 'zero emission' in production of water paint is realized, loss of raw materials and additives is reduced while discharge of wastewater and waste residue is avoided, and sewage-free, harmless and environment-friendly production process is realized.

A method of treating wastewater using an anaerobic bioreactor which contains a “bio-nest” structure to retain the microbial content and improve digestion efficiency is disclosed. The bionest system results in a longer SRT, good sludge mixing, and reduced wash-out of sludge. The system is particularly useful for treatment of lipid rich wastewater such as dairy wastewater.

The invention provides a wastewater treatment process. The wastewater treatment process comprises the following steps of: a, allowing wastewater to enter a concentration treatment device and concentrating, and separating part of water from the wastewater in a steam form to obtain concentrated wastewater; b, performing supercritical water oxidation on the concentrated wastewater to form a reacted fluid; c, pressurizing part of or all the reacted fluid by using a pressure production device to obtain a decompressed fluid, and providing a pressure condition for concentration treatment by using pressure produced by the pressure production device. The invention also provides a wastewater treatment system for the wastewater treatment process. The system comprises a wastewater concentrating device, a supercritical water reactor, and the pressure production device; the concentrating device is also provided with a chamber which realizes dehydration and has relatively high pressure, and a chamber with relatively low pressure, and the chamber with relatively low pressure is communicated with a pressure cavity. The wastewater treatment process and the wastewater treatment are high energy utilization rate.

In a process for the treatment of wastewater containing carbonaceous and nitrogenous contaminants, wastewater is mixed with aerobic microorganisms capable of converting carbonaceous biological oxygen demand (CBOD) into carbon dioxide, water, and biological cell mass. Oxygen is supplied to the reaction mixture for supporting reduction of the CBOD by the aerobic microorganisms in the reaction mixture. To substantially prevent nitrification of the nitrogenous contaminants in the reaction mixture and avoid the cost of downstream denitrification, the hydraulic residence time of the nitrogenous contaminants in the reaction mixture is controlled by removing partially treated water with dissolved ammonia from the reaction mixture, while retaining the biological cell mass in the reaction mixture. This separates the nitrogen load from the carbon load and enables independent treatment of these contaminants. The ammonia is scrubbed from the partially treated water to create fully treated water which is disposed or returned to the reaction mixture.

The invention belongs to the field of wastewater treatment, and particularly relates to a processing technology for electroplating synthetic wastewater. The process includes the specific steps of firstly, conducting a first-order reaction, wherein after the electroplating synthetic wastewater is subjected to complex breakage, coagulation, pH value regulation (the pH value is regulated to 10.5-11.5), flocculation, precipitation treatment and solid-liquid separation in sequence, supernatant liquid is first-order output water; secondly, conducting a second-order reaction, wherein after the first-order output water is subjected to complex breakage, coagulation, pH value regulation (the pH value is regulated to 10.5-11.5), an adsorption enhancement reaction, polyacrylamide flocculation, precipitation treatment and solid-liquid separation in sequence, the pH value of the supernatant liquid is regulated to 6-9, and standard discharge is achieved. After the electroplating synthetic wastewater is treated through the technology, the heavy metal content and the COD content in discharged water are both much lower than those of water treated through a traditional technology and meet the limit value standard in the table 3 of the GB21900-2008 Electroplating Pollutant Discharge Standard.

The invention discloses a carbon fiber-based mine wastewater treatment system and a groundwater decontamination process. The mine wastewater treatment system comprises a falling water aeration tank, a dosing tank, a primary sedimentation tank and multiple stages of carbon fiber contact oxidation tanks which are connected in series, wherein the falling water aeration tank, the dosing tank, the primary sedimentation tank and the carbon fiber contact oxidation tanks are connected sequentially, the dosing tank is used for adding a pH adjusting agent, the water inlet of the first-stage carbon fiber contact oxidation tank is connected with the water outlet of the primary sedimentation tank, and is provided with a decanter, and the water outlet of the last-stage carbon fiber contact oxidation tank is connected with a river channel or ditches; and the carbon fiber contact oxidation tanks are also provided with sludge discharge pipes and gates, each stage of the carbon fiber contact oxidation tanks is provided with a carbon fiber water purification system, and biofilm and algae fields which are formed by the carbon fiber water purification systems have the functions of retention, adsorption, adhesion, bridging, flocculation, bio-oxidation and bio-enzyme catalytic oxidation of wastewater. Iron manganese oxide which is a product of carbon fiber purification and treatment of wastewater is adopted as a catalyst, the operation cost is low, the decontamination effect is good, and the system is suitable for treatment of large-scale mine wastewater and groundwater sewage.

The invention discloses an acrylic acid industry wastewater treatment process, belonging to the field of wastewater treatment. The process comprises the following steps of: oxidizing acrylic acid production wastewater through electrocatalysis, leading the yielding water into a comprehensive adjusting tank, and adjusting water quality, water quantity and pH; leading the yielding water of the comprehensive adjusting tank into a pulse anaerobic reaction tank for anaerobic treatment; leading the yielding water of the pulse anaerobic reaction tank into a contact oxidation tank for aerobic treatment; and leading the treated wastewater into a secondary clarification tank for mud and water separation to finally obtain wastewater qualified to discharge. The traditional wastewater treatment process is optimized and combined once again, an electric hydrogenation and oxidation device is added before the anaerobic biochemical treatment, and a pulse anaerobic reacter is used for replacing the traditional anaerobic reaction tank. The invention has the advantages of simple treatment process and great treatment amount, the treatment efficiency is 2-3 times greater than that of the traditional acrylic acid wastewater recovery process, and the operating cost for treating each ton of wastewater only requires 5 yuan which is half that of the traditional acrylic acid wastewater recovery process.

The invention discloses a treatment method for acidic organic chemical wastewater with high COD (chemical oxygen demand) and high sulfate radical concentration, which mainly comprises the following steps: Ca(OH)2 pretreatment, anaerobic treatment, two-stage aerobic treatment, etc. After Ca(OH)2 pretreatment of the acidic organic chemical industry wastewater to remove most of sulfate radicals and H<+>, wastewater treatment microorganism main body and operation parameter factors are controlled so as to form an anaerobic wastewater treatment method with anaerobic bacteria being dominant and an aerobic aeration treatment method mainly using halophilic and haloduric aerobic microorganism treatment, and the anaerobic wastewater treatment method and the aerobic aeration treatment method are especially suitable for treating organic chemical industry wastewater with high COD, high sulfate radical concentration and low pH value.

The invention discloses a deep treatment method of naphthenic acid wastewater. Wastewater treatment comprises oil removing treatment, biological treatment, chemical precipitation-coagulation, sand filtration treatment and activated carbon adsorption treatment, wherein the chemical precipitation-coagulation is performed under the alkaline condition for making non-biodegradable naphthenic acid be reacted with lime to generate calcium naphthenate precipitates and remove the precipitated calcium naphthenate precipitates from wastewater under the coagulation action; the sand filtration is performed to treat colloids and suspended matters in wastewater; and the activated carbon adsorption is performed to further treat wastewater-dissolvable microorganism products and other non-biodegradable organic matters. Due to the adoption of the method, organic matters such as naphthenic acid and the like are effectively removed finally, the COD (Chemical Oxygen Demand) of treatment effluent is less than or equal to 50 mg / L, the strict local discharge standard (COD is less than or equal to 60 mg / L) can be met, and the environmental risk of wastewater discharge is lowered; and the method is suitable for performing deep treatment on naphthenic acid in various types of oil refining or oil field wastewater.

The invention relates to a method for preparing porous carbon for wastewater treatment. The method comprises the following steps: (1) pretreating semi coke with the grain size of 5 to 18 mm and soaking in a mixed solution of organic matters and inorganic salts at certain concentration; (2) directly activating products which are dried and dehydrated at the temperature of between 750 and 850 DEG C for 60 to 180 minutes; and (3) performing acid treatment on the activated products, washing and drying to obtain the porous carbon. According to the scheme, the semi coke directly serves as a raw material and one-step activating treatment is adopted without the steps of crushing, deashing, kneading, forming, carbonizing and the like, so the process is simple, the cost is low, and the prepared porous carbon has abundant micropore-mesopore-macropore structures, can adsorb various metal ions and organic matters in sanitary wastewater and industrial wastewater and is widely applied.

The invention provides a biomineralization-based acidic mine wastewater treatment system which comprises a water inlet end, a regulation unit, a biological oxidation mineralization unit, a lime neutralization unit, a lime dissolution unit, a neutralization residue reflux unit and a water outlet end. After the pH value of the acidic mine wastewater is regulated to 3.0, the acidic mine wastewater sequentially enters the biological oxidation mineralization unit and the lime neutralization unit to be treated, thereby reaching the discharge standard. By using the system and method provided by the invention, Fe<2+> in the acidic mine wastewater system can be completely oxidated within 48-60 hours, and meanwhile, the synthetic quantity of the secondary iron minerals can be enhanced by 30-60%. Compared with the conventional lime neutralization technique, the lime consumption is reduced by 30-50%.

The invention discloses a coking wastewater treatment system and method. The method comprises the steps of preparing dominant bacteria and putting the dominant bacteria into a membrane bioreactor, wherein the membrane bioreactor comprises an aerobic activated sludge tank and a membrane separation tank. The method specifically comprises the following steps: (1) taking aerobic activated sludge out of a coking wastewater discharge port; (2) acclimating, separating and purifying the aerobic activated sludge obtained in the step (1), thereby obtaining the dominant bacteria; (3) putting the dominant bacteria obtained in the step (2) into an aerobic sludge tank to react; and (4) after the wastewater, which is subjected to degradation reaction, enters a membrane separation tank, carrying out sludge-water separation. The invention efficiently removes specific organic pollutants in the coking wastewater by using the active dominant bacteria, thereby achieving the goal of degrading organic pollutants in a simple, efficient and quick way, so that the wastewater can be discharged after reaching the standard.

A system and method integrating treatment of waste, polar Fats / Oils / Greases (FOG) with conventional anaerobic wastewater treatment facilities for biologically fueling digestion of solids in, and steady state production of methane from treated wastewater streams that includes a slipstream loop circulating warmed, actively digesting sludge from the base to the head of the anaerobic wastewater treatment facility, a conditioning tank with input screened by a rock trap, actively digesting sludge pumped from the slipstream loop into the tank via the rock trap, before and after FOG wastes are pumped from a hauler tank via a hose connecting to the rock trap into the conditioning tank and mixed with actively digesting sludge in the tank to produce a feedstock slurry rich in volatile fatty acids for injection at a metered rate back into the actively digesting sludge slipstream loop for introduction at the head of the anaerobic wastewater treatment facility.

The invention discloses a process method for treating electroplating comprehensive wastewater, and relates to the field of electroplating wastewater treatment. The method at least comprises the following steps: a, intensively exhausting wastewater into a comprehensive wastewater tank, pumping the wastewater into an oil removing tank by a pump, and entering a settling tank through a regulating tank; b, pumping out a liquid supernatant of the settling tank by the pump to enter quartz sand, active carbon and a microfiltration column to further filter water for mainly removing fine suspended matters of organic substances in the wastewater. The process method disclosed by the invention can be used for directly mixing wastewater of an electroplating workshop without pretreatment and separating treatment, and does not need to regulate PH value in stages; all wastewater passes through in one step, and the process flow is simple, so that operation of a worker and industrial production are facilitated; moreover, heavy metals and water resource can be recycled from electroplating wastewater, so that pollution of wastewater on environment is relieved or avoided, and electroplating clean production is realized, and therefore, electroplating wastewater of gold, sliver, nickel, copper, and the like, with higher additional value can be absorbed and recycled by resin, and good economic benefits are produced.

The invention discloses a wastewater treatment flocculating agent taking wheat bran as a raw material, and a preparation method of the wastewater treatment flocculating agent. The preparation method of the wastewater treatment flocculating agent comprises: adding an appropriate amount of the wheat bran into a container, adding distilled water about 10-30 timers of the weight of the wheat bran, rising the temperature to 75-85 DEG C, adding inorganic metal salt under stirring, adding a surfactant and a coagulant about 3-6 wt% of the bran, utilizing ultrasonic dispersion, performing stirring for 2-3 h at 80-90 DEG C, performing heating slowly to 100 DEG C in a dryer, enabling the water content in wheat bran to be lower than 20%, stopping heating, reducing the temperature to the room temperature, performing 80-100 mesh grinding, and obtaining the flocculating agent after package. The flocculating agent provided by the invention has strong hydrophilicity, strong adsorbability and good stability, has very strong adsorption precipitation action on heavy metal, oil stain and solid particles in a wastewater treatment process, and is cheap, practical and non-toxic, thereby having a wide development prospect in the water treatment technology application field.

The invention discloses a multistage anaerobic wastewater treatment method which comprises steps as follows: wastewater, of which the CODcr is 2000-20000 mg / L and the pH value is 6-10, is pumped in from the water inlet of a multistage anaerobic wastewater treatment device and mixed with granular sludge on the bottom of the multistage anaerobic wastewater treatment device; the water inlet flow is adjusted to control the hydraulic retention time to 1-5 days; and the wastewater treated by the multistage anaerobic wastewater treatment device is discharged via the water outlet. The fluidized bed structure anaerobic region of the multistage anaerobic wastewater treatment device is in a completely-mixed fluidized state in the starting stage, thereby reinforcing the mass transfer effect between the particle sludge and wastewater, enhancing the biochemical reaction rate, accelerating the sludge granulation progress and greatly shortening the reaction starting time; and in the operating stage, the internal and external circulations of sludge-water mixture are implemented, thereby effectively eliminating the problems of short flow and dead spots, reinforcing the mass transfer effect and greatly enhancing the removal capacity of organic substances.

The invention provides a salt-containing wastewater treatment system. The salt-containing wastewater treatment system comprises a clarification and softening unit, a membrane filtration unit, a cationic resin softening unit, a carbon dioxide removal unit, a first reverse osmosis unit, a chelate resin softening unit, a second reverse osmosis unit, a nanofiltration unit, a freezing crystallization unit and other treatment units. The invention further provides a salt-containing wastewater treatment method. According to the salt-containing wastewater treatment system and treatment method, salt-containing wastewater can be converted into products such as acid, alkali, mirabilite and the like required to be purchased from the outside in the water treatment process, mixed organic matter containing salt which cannot be used is not generated, scaling and sewage blocking due to reverse osmosis and nanofiltration can be greatly relieved, long-time, stable and reliable operation of the treatment system can be guaranteed, the wastewater treatment cost is reduced, the concentrated water can be completely treated in the system, no secondary pollution is caused, and zero discharge and resource utilization of the wastewater are realized.