CN114212946A - RO concentrated water treatment system and treatment method - Google Patents
RO concentrated water treatment system and treatment method Download PDFInfo
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- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
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- C02F9/00—Multistage treatment of water, waste water or sewage
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- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/28—Treatment of water, waste water, or sewage by sorption
- C02F1/283—Treatment of water, waste water, or sewage by sorption using coal, charred products, or inorganic mixtures containing them
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- C02F1/722—Oxidation by peroxides
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- C02F1/725—Treatment of water, waste water, or sewage by oxidation by catalytic oxidation
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Abstract
The invention discloses a RO concentrated water treatment system and a treatment method. An RO concentrated water treatment system comprises a membrane Fenton system, a biological activated carbon filter and/or an aeration biological filter which are connected in sequence. The RO concentrated water treatment system provided by the invention organically combines a membrane Fenton system with a BAC and/or BAF biofilm method, so that the advantages are obtained, the advantages are complemented, the treatment effect is improved, and the comprehensive cost is reduced; the dosage of the Fenton medicament can be adjusted according to the water quality of the inlet water and the water outlet requirement so as to meet different water quality and water outlet requirements.
Description
Technical Field
The invention relates to the technical field of wastewater treatment, in particular to a RO concentrated water treatment system and a treatment method.
Background
The reverse osmosis membrane (RO) separation technology has the advantages of no phase change of materials, low relative energy consumption, good effects of desalting and removing organic matters, mature and reliable treatment process, simple equipment, high automation degree, easy operation and management and the like, and is widely applied to the fields of advanced treatment and recycling of petrochemical, coal chemical industry, printing and dyeing, papermaking and municipal sewage. The reverse osmosis membrane (RO) concentrated water generated along with the technology has the characteristics of high organic pollutant content, poor biodegradability, high salt content, high hardness, high toxicity and the like, and is high-concentration wastewater which is difficult to treat. With the national emission reduction policy and the requirement on wastewater reuse, more and more wastewater is produced.
At present, the RO concentrated water is mainly treated and disposed at home and abroad by discharging surface water and seawater into a municipal sewage treatment system, realizing zero emission or near zero emission through evaporation concentration, recycling and the like. Although zero emission and resource utilization avoid environmental emission and secondary pollution, the practical application of the technology is limited by high energy consumption, large investment, complex process, high requirement on equipment, immature technology and the like of the technologies such as membrane distillation, enhanced evaporation, evaporative crystallization and the like. Therefore, direct or indirect discharge is still the main treatment mode of the RO concentrated water, and the research on the terminal treatment technology to realize the discharge or reuse up to the standard will continue to become the most promising and feasible treatment mode of the RO concentrated water.
The prior art for treating organic matters in RO concentrated water mainly includes coagulation precipitation, adsorption, ozone oxidation, fenton and fenton-like oxidation, photocatalytic oxidation, ultrasonic oxidation, electrochemical oxidation, advanced oxidation-biochemical combination, and the like. Coagulating sedimentation, namely adding a coagulant into wastewater to enable fine particles and colloidal suspended matters to be aggregated into larger particles for sedimentation, has the advantages of simple operation, easy control and high removal rate, is difficult to remove micromolecule and soluble organic matters, has high medicament adding cost and generates a large amount of precipitated sludge, and is often used as a pretreatment process of advanced oxidation. The adsorption method utilizes the physical adsorption, chemical adsorption, oxidation, catalytic oxidation, reduction and other performances of adsorbents such as activated carbon and the like to remove pollutants in water, has the advantages of capability of removing various organic matters and good effluent quality, and has the defects of large consumption of the adsorbents, need of regeneration and high cost. Ozone oxidation method, ozone can be decomposed at normal temperature to produce monatomic oxygen and hydroxyl radical with strong oxidizing power, has the advantages of disinfection, color removal, deodorization and organic matter removal, and has the disadvantages of low ozone utilization rate, insufficient oxidizing power and low treatment effect. Fenton and Fenton-like oxidation processes using Fe2+Catalysis H2O2The generated hydroxyl free radicals realize the degradation of organic pollution, and have the advantages of mild reaction conditions, convenient operation and high treatment efficiency, and have the defects of low utilization rate of hydrogen peroxide, high energy consumption and large dosage of medicament. Photocatalytic oxidation, adding proper amount of oxidant into waste water, and under the action of ultraviolet light (visible light), generating hydroxyl radical with strong oxidizing propertyHas the advantage of oxidizing most organic matters into CO2、H2O and other small molecular organic matters have better treatment effect on colored substances, and the defect is that the treatment effect on the organic matters is not ideal by singly using photocatalysis. The ultrasonic oxidation method realizes the degradation of organic matters by generating cavitation and free radical effect through high-energy ultrasonic waves, has the advantages of simple operation, capability of removing partial organic pollutants in water and has the defects of high ultrasonic oxidation treatment cost and poor removal effect on hydrophilic and nonvolatile organic matters. The electrochemical oxidation method has the advantages that the organic matters which are difficult to degrade and ammonia nitrogen can be oxidized, a certain removal effect on chromaticity is achieved, the electrochemical oxidation energy consumption is high, and toxic byproducts are generated in the electrode material in the electrolysis process. The advanced oxidation-biochemical combined method is characterized in that organic matters which are difficult to biodegrade are converted into intermediate products which are easy to biodegrade through advanced oxidation, and pollutants are oxidized into CO through biological oxidation2、H2O and mineral salts have the advantages of good organic matter removing effect and reduced operation cost, and have the disadvantages of long operation period in the biological treatment process because the effect depends on the amount of biodegradable substances generated by oxidation.
Advanced oxidation technology has proven to be a suitable treatment technology for RO concentrate. The advanced oxidation process is closely related to the generation of free radicals, so that the efficient excitation of the free radicals is very critical, but the harsh conditions of high temperature, high pressure, electricity, sound, light, catalysts and the like required for exciting the generated free radicals limit the popularization and application of most advanced oxidation technologies, the Fenton technology mainly has unique advantages compared with the ozone technology, the Fenton technology has stronger oxidation capacity, the Fenton reagent can generate hydroxyl free radicals with strong oxidation performance, the electrochemical oxidation potential of the Fenton reagent is 2.8V, the hydroxyl free radicals are one of the most active oxidants discovered at present, and the electrochemical oxidation potential of ozone is 2.08V; secondly, Fenton can remove pollutants which cannot be removed under the action of oxidation through mechanisms such as coagulation, adsorption, coprecipitation and the like, so that the organic pollutant removal efficiency is higher; thirdly Fenton's reagent (Fe)2+And H2O2) Is easier to obtainThe method is environment-friendly, hydroxyl free radicals can be efficiently generated at normal temperature and normal pressure, and compared with the method, the method for obtaining ozone by using an ozone technology has the defects of harsh conditions, low ozone utilization rate, high operation cost and the like; fourthly, the Fenton technology has higher tolerance to the inlet water SS than the ozone technology, so the pretreatment requirement is lower. However, the traditional Fenton has the defects of large floor area, unstable effluent quality, low medicament use efficiency, large sludge generation amount and the like.
Patent application CN 103121743A proposes a method for treating urban sewage to reuse reverse osmosis concentrated water by applying a treatment process of 'Fenton oxidation reaction tank + sedimentation tank + denitrification type biological filter', wherein Fenton reagent is added into the Fenton oxidation reaction tank, and Fe is additionally added3+Or Al3+And the coagulation agent can remove COD and total phosphorus simultaneously. The Fenton effluent enters a denitrification type biological filter after solid-liquid separation in a sedimentation tank, and the biological filter is likely to be blocked due to sludge leakage due to poor sedimentation efficiency, so that the operation risk is high. Patent application CN 103723779a proposes a fenton reaction system capable of controlling the dosage of chemicals to treat RO concentrate. The inlet water of the system is RO concentrated water after denitrification treatment, the appropriate range of COD is about 60mg/L, the application range is narrow, and the RO concentrated water is subjected to pretreatment. The controllable medicament of this patent is thrown and add the kind, actually changes throwing of medicament, throws iron chloride or iron chloride + hydrogen peroxide solution through the selectivity and realizes the switch of coagulating sedimentation and advanced oxidation, does not realize the meticulous throwing of fenton's medicament and throws. Patent application CN 105984991a discloses a sewage advanced treatment process, which combines various sewage treatment systems such as an anoxic BAF biofilter, an aerobic BAF biofilter, an ozone contact reaction tank and an aerobic BAC biofilter. Ozone has the defects of low utilization rate, insufficient oxidizing power, low treatment effect and the like, and ozone has higher requirement on inlet water SS, so that the ozone process cannot be arranged at the foremost end, and the process flow is long, the system is complex and the operation difficulty is high. Patent application CN109368870A mentions a method for treating RO concentrate of printing and dyeing wastewater by using the conventional Fenton technique, and mentions the effect of removing COD, which has been described above and compared with the conventional Fenton technique, and besides, does not mention the advantages of the membrane Fenton techniqueRelates to a method for removing ammonia nitrogen and TN in RO concentrated water.
Disclosure of Invention
The invention aims to solve the problems of difficult treatment and high treatment cost of RO concentrated water in the prior art, and aims to provide an RO concentrated water treatment system and an RO concentrated water treatment method.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
an RO concentrated water treatment system comprises a membrane Fenton system, a biological activated carbon filter and/or an aeration biological filter which are connected in sequence; the RO concentrated water treatment system can be a membrane Fenton system and a biological activated carbon filter which are connected in sequence, can be a membrane Fenton system and an aeration biological filter which are connected in sequence, and can also be a membrane Fenton system, a biological activated carbon filter and an aeration biological filter which are connected in sequence; further preferably, the RO concentrated water treatment system comprises a membrane Fenton system, a biological activated carbon filter and a biological aerated filter which are connected in sequence; the membrane Fenton system comprises a Fenton reaction tank, an alkali regulation tank and a membrane reaction tank which are connected in sequence.
Preferably, the RO concentrated water treatment system further comprises a produced water storage tank; the water production storage tank is arranged behind the membrane Fenton system and in front of the biological activated carbon filter or the biological aerated filter; further preferably, the pH value in the water production storage tank is 6.0-6.5; in some preferred embodiments of the invention, the RO concentrated water treatment system comprises a membrane Fenton system, a water production storage tank, a biological activated carbon filter and a biological aerated filter which are connected in sequence.
The invention also provides an RO concentrated water treatment method, wherein the wastewater sequentially passes through the RO concentrated water treatment system to realize the treatment of the wastewater; further preferably, the wastewater sequentially passes through the membrane Fenton system, the water production storage tank, the biological activated carbon filter and the biological aerated filter, so that the wastewater treatment is realized.
Preferably, in the RO concentrated water treatment method, the hydraulic retention time of the membrane Fenton system is 1.8-2.8 h; further preferably, the hydraulic retention time of the membrane Fenton system is 1.9-2.6 h; still further preferably, the hydraulic retention time of the membrane fenton system is 2.0-2.5 h.
Preferably, in the RO concentrated water treatment method, the pH value of an alkali regulation pool of the membrane Fenton system is more than or equal to 4.0; the pH range of the alkali regulation pool is wide, theoretically, the pH only needs to meet the requirement of Fe3+Converting into ferric hydroxide; the pH value of the alkali adjusting tank is reduced, the biological activated carbon filter (BAC) and the Biological Aerated Filter (BAF) in the biochemical section use slightly acidic inlet water to culture and domesticate high-efficiency microorganisms, the advantages of each process section are fully exerted, the quality of outlet water is ensured, and meanwhile, the operating cost is greatly reduced.
Preferably, in the RO concentrated water treatment method, the hydraulic retention time of the soda adjusting tank of the membrane Fenton system is 8-35 min; further preferably, the hydraulic retention time of the soda pond of the membrane Fenton system is 10-30 min.
Preferably, in the RO concentrated water treatment method, an ultrafiltration membrane is adopted in a membrane reaction tank of a membrane Fenton system; further preferably, the membrane filtration precision is 0.03-0.05 μm; still more preferably, the membrane filtration precision is 0.04. mu.m.
Preferably, in the RO concentrated water treatment method, the sludge concentration in the membrane reaction tank of the membrane Fenton system is 3000-7000 mg/L; further preferably, the concentration of the sludge in the membrane reaction tank is 4000-6000 mg/L.
Preferably, in the RO concentrated water treatment method, the operating membrane flux of the membrane reaction tank of the membrane Fenton system is set to be 15-50L/(m)2H); further preferably, the operating membrane flux of the membrane reaction cell is set to 20 to 45L/(m)2H); the operating membrane flux of the membrane reaction tank is set to be 30-40L/(m)2·h)。
Preferably, in the RO concentrated water treatment method, the hydraulic retention time of a membrane reaction tank of the membrane Fenton system is 20-70 min; further preferably, the hydraulic retention time of the membrane reaction tank is 25-65 min; still further preferably, the hydraulic retention time of the membrane reaction tank is 30-60 min.
Preferably, in the RO concentrated water treatment method, the pH value of the membrane Fenton system is 3.0-5.5; it is further preferred that the membrane fenton system has a pH of 3.5-5.0.
Preferably, in the RO concentrated water treatment method, the dissolved oxygen of the effluent of the biological activated carbon filter (BAC) is 0.8-1.8 mg/L; further preferably, the dissolved oxygen of the effluent of the biological activated carbon filter (BAC) is 0.9-1.6 mg/L; still more preferably, the dissolved oxygen of the effluent of the biological activated carbon filter (BAC) is 1.0-1.5 mg/L.
Preferably, in the RO concentrated water treatment method, the empty bed retention time of the biological activated carbon filter (BAC) is 50-100 min; further preferably, the empty bed residence time is 55-95 min; still further preferably, the empty bed residence time is 60-90 min.
Preferably, in the RO concentrated water treatment method, the filler in the biological activated carbon filter (BAC) is biological activated carbon filler, which comprises one of coconut shell and activated carbon; further preferably, the filler is coconut shell, and the adsorption iodine value is 800-1200 mg/g.
Preferably, in the RO concentrated water treatment method, a carbon source is added into a biological activated carbon filter (BAC); further preferably, the carbon source comprises at least one of sodium acetate, methanol, acetic acid and glucose, and the adding amount is 4-5 according to the C/N ratio.
Preferably, in the RO concentrated water treatment method, the biological activated carbon filter (BAC) is in a cylindrical shape, the diameter is 200mm, and the height is 2m, so that a dissolved oxygen gradient exists in the transverse direction and the longitudinal direction, and the removal of ammonia nitrogen and TN is facilitated; BAC combines the biodegradation and filtration properties of BAF and the adsorption effect of activated carbon.
Preferably, in the RO concentrated water treatment method, the dissolved oxygen of the effluent of the aeration biological filter (BAF) is 1.8-3.2 mg/L; further preferably, the dissolved oxygen of the effluent of the Biological Aerated Filter (BAF) is 1.9-3.1 mg/L; still more preferably, the dissolved oxygen of the effluent of the Biological Aerated Filter (BAF) is 2.0-3.0 mg/L.
Preferably, in the RO concentrated water treatment method, the empty bed retention time of the Biological Aerated Filter (BAF) is 2.5-4.5 h; further preferably, the empty bed retention time of the Biological Aerated Filter (BAF) is 2.7-4.2 h; still further preferably, the empty bed retention time of the Biological Aerated Filter (BAF) is 3.0-4.0 h.
Preferably, in the RO concentrated water treatment method, the filler in the Biological Aerated Filter (BAF) comprises at least one of ceramsite and zeolite; further preferably, the filler is ceramsite, and the ceramsite is commercially available ordinary ceramsite.
Preferably, in the RO concentrated water treatment method, the Biological Aerated Filter (BAF) is in a cylindrical shape, the diameter is 350mm, and the height is 2m, so that a dissolved oxygen gradient exists in the transverse direction and the longitudinal direction, and ammonia nitrogen and COD are more favorably removed.
Preferably, in the RO concentrated water treatment method, a return pipeline is arranged between the biological activated carbon filter and the biological aerated filter, and the filter can be started or not started according to the actual water quality condition.
Preferably, the RO concentrated water treatment method further comprises a step of cleaning an inner membrane in a membrane reaction tank of a membrane Fenton system, and the method specifically comprises the following steps: by means of H2SO4And/or cleaning the inner membrane of the membrane reaction tank by hydrogen peroxide; further preferably, the method specifically comprises the following steps: firstly, 0-20000mg/L H is adopted2SO4Cleaning, and cleaning the inner membrane of the membrane reaction tank by using 0-1000mg/L hydrogen peroxide; still further preferably, the method specifically comprises the following steps: adopting 10000-15000mg/L H2SO4After cleaning for 5-10min, cleaning the inner membrane of the membrane reaction tank for 5-10min by using 500-1000mg/L hydrogen peroxide.
Preferably, in the RO concentrated water treatment method, the water quality of the wastewater satisfies at least one of the following conditions: COD is less than or equal to 300mg/L, and total nitrogen is less than or equal to 45 mg/L; total phosphorus is less than or equal to 5.0 mg/L; the alkalinity is less than or equal to 1800 mg/L; the hardness is less than or equal to 600.0 mg/L; the chloride ion is less than or equal to 4000 mg/L; the salt content (TDS) is less than or equal to 15000 mg/L; the fluorine ion is less than or equal to 5.0 mg/L; further preferably, the water quality of the wastewater meets at least one of the following conditions: COD is less than or equal to 300 mg/L; the hardness is less than or equal to 600.0 mg/L; the chloride ion is less than or equal to 4000 mg/L; the salt content (TDS) is less than or equal to 15000 mg/L; the fluorine ion is less than or equal to 5.0 mg/L; still further preferably, the water quality of the wastewater satisfies the following conditions: COD is less than or equal to 300 mg/L; the hardness is less than or equal to 600.0 mg/L; the salt content (TDS) is less than or equal to 15000 mg/L.
The invention also provides an automatic dosing method, which comprises the steps of detecting the flow and COD concentration of the wastewater before entering the membrane Fenton system on line, obtaining the dosing amount of the medicament according to an operation formula, and dosing the Fenton medicament to the membrane Fenton system through the automatic dosing device.
Preferably, the automatic dosing method specifically comprises the following steps: an on-line flow meter and an on-line COD instrument are arranged on a water inlet pipeline of the RO concentrated water treatment system, a medicine storage tank and a medicine feeding pump are additionally arranged, the medicine feeding pump is provided with the on-line flow meter and a frequency converter, the flow and COD concentration data of wastewater before entering the membrane Fenton system are input into a controller, the controller controls the medicine feeding pump, and the medicine feeding pump adds a Fenton medicament into a Fenton reaction tank from the medicine storage tank; when the online COD instrument is not monitored accurately, the COD value can be manually input through the actual numerical value monitored manually.
Preferably, the operation formula of the automatic dosing method is as follows:
in the formula:
Qin，m3the water inlet flow is the read flow value of the water inlet electromagnetic flowmeter;
CODin, mg/L; the online COD instrument test data is the read COD value on the online COD instrument;
the COD value of the effluent is set to be 50 according to the standard A of grade 1 of pollutant discharge Standard of urban Sewage treatment plant (GB18918-2002), and the COD value can be adjusted according to actual effluent;
a is hydrogen peroxide (100%): CODin, mass concentration ratio;
b is ferrous (Fe)2+): hydrogen peroxide (100%), mass concentration ratio;
m1 percent, the mass fraction of ferrous sulfate heptahydrate;
rho 1, g/L, density of ferrous sulfate heptahydrate;
m2 percent, the mass fraction of hydrogen peroxide;
in some preferred embodiments of the present invention, a is 1.0 and b is 1.5; in actual operation, m1 is 27.5%, ρ 1 is 1190g/L, m2 is 27.5%, ρ 2 is 1068 g/L.
Feedback correction, comparing the actual water outlet value COD with the set value CODeffValue, by adjusting the set COD at a suitable step (e.g. r%) according to the discharge requirement of the actual effluent CODeffThe values or a and b reach the emission standard.
The invention has the beneficial effects that:
the RO concentrated water treatment system provided by the invention adopts a membrane Fenton system to be organically combined with the BAC and/or BAF biological membrane reaction tank, so that the advantages of the two are obtained and the advantages of the two are complementary.
The RO concentrated water treatment method improves the treatment effect, reduces the comprehensive cost, and can adjust the dosage of the Fenton medicament according to the water quality of inlet water and the water outlet requirement so as to meet different water quality and water outlet requirements.
The RO concentrated water treatment system has stable process and high automation degree, can realize completely unattended operation, and can be popularized and applied in a large scale; the occupied area is greatly reduced, and compared with the traditional Fenton method, the occupied area can be reduced by more than 30-50%.
The RO concentrated water treatment method has more efficient and stable removal effect, and efficiently removes the nonbiodegradable high-difficulty COD, TP, TN and NH3N, TSS and various harmful anions (in particular F)-) The high-standard discharge or reuse of the wastewater is realized; by means of the process advantages, the pH of the adjusted alkaloid is greatly reduced, the acidic inlet water is used for BAC + BAF in the biochemical section to culture and domesticate efficient microorganisms, the efficient microorganisms suitable for RO concentrated water can be cultured and domesticated, the advantages of each process section are fully played, the effluent quality is guaranteed, and meanwhile, the operation cost is greatly reduced.
The invention develops an automatic dosing method, is applied to the RO concentrated water treatment system, ensures that the usage amount of the Fenton agent is less than that of the traditional Fenton agent, the sludge discharge amount is less, the operation cost is lower and unnecessary waste of the traditional Fenton agent is avoided under the condition of ensuring the same effluent quality, and the cost of treating RO concentrated water per ton is less than 2.5 yuan per ton, so that the RO concentrated water treatment technology is greatly reduced compared with the existing RO concentrated water treatment technology.
By adopting the novel membrane cleaning program and the novel membrane cleaning mode, the hydrogen peroxide is used for replacing the traditional sodium hypochlorite, the cleaning effect is more stable, and the cost of hydrogen peroxide cleaning agent is reduced by 0.033 yuan/ton of water compared with that of sodium hypochlorite cleaning. In addition, because the membrane Fenton system of the invention uses hydrogen peroxide as an oxidant, if the membrane Fenton system is cleaned by hydrogen peroxide, the types of medicaments can be reduced, the design of the system can be simplified, and the engineering cost can be saved.
The RO membrane concentrated water treatment system has great market potential, the industrial wastewater is increased day by day, the existing sewage plant is improved in upgrading, and the requirement of water reuse rate is increased, so that the membrane filtration technology is concerned. The invention provides a competitive treatment method for RO concentrated water generated along with the large-scale use of the RO membrane technology, and thoroughly solves the worries about the rapid popularization of the membrane filtration technology.
Drawings
FIG. 1 is a diagram of a RO concentrate treatment system.
FIG. 2 is a diagram of a RO concentrate treatment system according to an embodiment.
FIG. 3 is a graph showing the tendency of change in COD concentration during the operation of example 1.
FIG. 4 is a graph showing the change in TN concentration during the operation of example 1.
FIG. 5 is a graph showing the variation of the ammonia nitrogen concentration during the operation of example 1.
FIG. 6 is a graph showing the trend of the TP concentration during the operation of example 1.
FIG. 7 is a graph showing the initial water permeability of the membrane when washed with sodium hypochlorite.
FIG. 8 is a graph showing the change of initial water permeability of the membrane when the membrane is washed with hydrogen peroxide.
FIG. 9 shows the cumulative COD frequency of effluent in example 2.
FIG. 10 shows the cumulative TOC frequency of effluent water of example 2.
FIG. 11 shows cumulative frequency of TN effluent in example 2.
FIG. 12 shows the cumulative frequency of ammonia nitrogen in the effluent of example 2.
Detailed Description
The embodiments of the present invention will be described in detail below, and the embodiments described by referring to the drawings are exemplary only for the purpose of illustrating the present invention and are not to be construed as limiting the present invention.
The present invention will be described in further detail with reference to specific examples.
In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "connected" and "connected" are to be interpreted broadly, e.g., as a fixed connection, a detachable connection, or an integral connection; can be mechanically or electrically connected; they may be directly connected to each other, indirectly connected to each other through an intermediate member, or connected to each other through the inside of two members. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
The starting materials, reagents or apparatus used in the examples and comparative examples were obtained from conventional commercial sources or can be obtained by a method of the prior art, unless otherwise specified. Unless otherwise indicated, the testing or testing methods are conventional in the art.
As shown in figure 1, the RO concentrated water treatment system comprises a membrane Fenton system, a biological activated carbon filter and/or a biological aerated filter which are connected in sequence.
An RO concentrate treatment system according to an embodiment of the present invention will be described below with reference to fig. 2.
The RO concentrated water treatment system comprises a membrane Fenton system, a water production storage tank, a biological activated carbon filter, an aeration biological filter and an automatic dosing system, wherein the automatic dosing system feeds back data to a controller through online inflow monitoring and online COD monitoring, the controller controls a dosing pump to dose a Fenton medicament into a Fenton reaction tank through operation, and the automatic dosing method comprises the following operation formula:
in the formula: a is 1.0, b is 1.5, m1 is 27.5%, ρ 1 is 1190g/L, m2 is 27.5%, ρ 2 is 1068g/L, CODin is the intake COD concentration of the actual embodiment, CODeff is 50mg/L, Qin is the intake flow of the actual embodiment.
As shown in fig. 2, in an embodiment of the fenton-based wastewater treatment system, wastewater passes through a membrane fenton system, a water production storage tank, a biological activated carbon filter and a biological aerated filter in sequence and is discharged after reaching standards; through the automatic dosing system, the dosage of the Fenton medicament is adjusted in real time according to the water inlet condition.
Example 1
The waste water treatment plant of printing and dyeing industry in Guangdong province can co-treat 10 production waste water of printing and dyeing enterprises at present. Generates the RO concentrated water 8500m every day3And d. The RO concentrated water has the characteristics of high salt content, poor biodegradability, mainly soluble pollutants and the like. The main water quality indexes of the RO concentrated water are as follows: 250mg/L of COD 150-. The RO concentrated water treatment system shown in FIG. 2 was used for treating wastewater, and the operational parameters of this example are shown in Table 1 below.
Table 1 operating parameters of example 1
The change trend graph of the COD concentration in the operation process of this example is shown in fig. 3, the change trend graph of the TN concentration in the operation process of this example is shown in fig. 4, the change trend graph of the ammonia nitrogen concentration in the operation process of this example is shown in fig. 5, and the change trend graph of the TP concentration in the operation process of this example is shown in fig. 6. Through the above-mentioned treatment systemAfter treatment, COD in the effluent is 20-40mg/L, TN is 5-9mg/L, ammonia nitrogen is less than 0.5mg/L, TP is less than 0.1mg/L, and fluoride ions (F)-) Less than 0.5mg/L, the COD of the effluent can stably reach the first class A standard of pollutant discharge Standard of municipal wastewater treatment plant (GB18918-2002), and the TSS can be stably kept below the detection limit.
Through operation statistics of a period of time, the operation cost of the invention comprises 1.85 yuan/ton water of medicament cost, 0.16 yuan/ton water of membrane cleaning cost, 0.34 yuan/ton water of sludge disposal cost and 2.35 yuan/ton water of total cost.
The automatic dosing method is compared with the traditional dosing method:
on the basis of the operation parameters, an automatic dosing method is not adopted, a traditional dosing method is adopted, the traditional dosing method means that real-time adjustment is not carried out according to the COD of the inlet water and the inlet water amount, the dosing amount of the medicament is carried out according to the larger inlet water amount and the larger COD value, the water quality of the outlet water is ensured, and the statistical data of the medicament usage amount of the traditional dosing method and the automatic dosing system which operate for about one year are shown in the following table 2.
TABLE 2 comparison of the dosage of the traditional dosing method and the automatic dosing system
In the traditional dosing mode, under the condition that the COD (chemical oxygen demand) of inlet water is lowered or the water amount is reduced, the dosage of a medicament is too much, and the medicament is wasted; under the condition that the COD of the inlet water is high or the water quantity is large, the dosage of the medicament is insufficient, the removal effect is not ideal, and therefore the traditional medicament adding mode causes unnecessary medicament waste. By adopting the automatic dosing method, the dosing quantity is adjusted in real time according to the COD (chemical oxygen demand) of the inlet water and the inlet water quantity, unnecessary waste of the medicament is avoided on the premise of ensuring the water quality, the most appropriate medicament quantity can be accurately dosed according to the inlet water quality and the inlet water quantity in real time, the outlet water quality is ensured, the water quality fluctuation is greatly reduced, a large amount of waste caused by excessive dosing of Fenton medicaments due to security is avoided, and the medicament cost is greatly reduced.
The invention develops a novel membrane cleaning program and a novel membrane cleaning mode, the membrane cleaning is carried out by adopting hydrochloric acid, then adopting hydrogen peroxide, for comparison, sodium hypochlorite is adopted to replace the hydrogen peroxide, specific membrane cleaning operation parameters are shown in table 1, the cleaning effect of the hydrogen peroxide is more stable than that of the sodium hypochlorite, and the cleaning cost is reduced by 0.03 yuan/ton of water compared with that of sodium hypochlorite cleaning. The initial water permeability of the membrane when cleaned with sodium hypochlorite is shown in fig. 7, and the initial water permeability of the membrane when cleaned with hydrogen peroxide is shown in fig. 8.
Example 2
On the basis of example 1, the bypass process shown in fig. 1 was selected for wastewater treatment, and the treatment effects of membrane fenton + BAC, membrane fenton + BAF and membrane fenton were compared and studied. The accumulated frequency of COD of the effluent is shown in figure 9, the accumulated frequency of TOC of the effluent is shown in figure 10, the accumulated frequency of TN of the effluent is shown in figure 11, and the accumulated frequency of ammonia nitrogen of the effluent is shown in figure 12.
Comparative example 1
The wastewater was treated using the conventional Fenton + BAC + BAF process with the operating parameters shown in Table 3 below.
Table 3 operating parameters of comparative example 1
The removal effect of the membrane fenton of example 1 was improved by 20-30% compared to the removal effect of the conventional fenton. Most of the membrane Fenton removed is non-biodegradable COD, and meanwhile, the biodegradability of the effluent is improved, so that the membrane Fenton can directly react on the subsequent biochemical effect. The effects of the membrane fenton treatment of the conventional fenton and example 1 are shown in table 4 below.
Table 4 comparison of treatment effects of conventional fenton and membrane fenton
To compare the soda costs of membrane fenton + BAC + BAF and traditional fenton + BAC + BAF, both systems were run simultaneously for a period of time, with the operating parameters as reported in example 1 and comparative example 1, and the cut-off details are shown in table 5 below:
TABLE 5 consumption of liquid caustic soda in example 1 and comparative example 1
The adoption of the membrane Fenton + BAC + BAF system can greatly reduce the alkali adjusting cost, and the main reasons are as follows 3:
the solid-liquid separation of the embodiment 1 is completed through an ultrafiltration membrane, which is different from a traditional Fenton sedimentation tank, has no requirement on the sedimentation performance and speed of sludge mixed liquor, and does not need to add flocculating agents such as PAC (polyaluminium chloride) or PAM (polyacrylamide), so that in this regard, compared with the traditional Fenton, the operation control is easier, the water outlet is safer, and no secondary pollution is caused by adding coagulant aids; the pH range of the alkali adjusting tank is wider, and theoretically, the pH only needs to meet the requirement of adding Fe3+And converting into ferric hydroxide.
Secondly, a water production tank is arranged for subsequent alkali adjustment, and researches show that when the pH value is adjusted to meet the requirements of respective processes, the alkali amount consumed by alkali adjustment in the concentration of the iron mud (comparative example) is about 20-60% more than that of the water produced after membrane filtration in the example 1. According to actual operation data on site, the alkali consumption per ton of water is saved by about 50 percent compared with the traditional process.
Thirdly, culturing and domesticating the acidic high-efficiency microorganism under the condition that the pH of BAC + BAF inlet water is 6.5.
Although the present invention has been described with reference to the above embodiments, it should be understood that the present invention is not limited thereto, and various changes, substitutions, and alterations can be made without departing from the spirit and scope of the invention.
Claims (10)
1. An RO concentrated water treatment system is characterized by comprising a membrane Fenton system, a biological activated carbon filter and/or an aeration biological filter which are connected in sequence.
2. An RO concentrate treatment system according to claim 1, further comprising a product water storage tank; the water production storage tank is arranged behind the membrane Fenton system and in front of the biological activated carbon filter or the biological aerated filter.
3. A method for treating RO concentrate, characterized in that wastewater is sequentially subjected to the RO concentrate treatment system according to claim 1 or 2.
4. A process of RO concentrate water treatment according to claim 3, characterized in that the hydraulic retention time of the membrane fenton system is 1.8-2.8 h.
5. A method for treating RO concentrated water according to claim 3, characterized in that the pH of the soda adjusting tank of the membrane Fenton system is not less than 4.0.
6. An RO concentrated water treatment method according to claim 3, characterized in that the dissolved oxygen of the effluent of the biological activated carbon filter is 0.8-1.8 mg/L; the residence time of the air bed of the biological activated carbon filter is 50-100 min.
7. A RO concentrated water treatment method according to claim 3, characterized in that the dissolved oxygen in the effluent of the biological aerated filter is 1.8-3.2 mg/L; the residence time of the air bed of the biological aerated filter is 2.5 to 4.5 hours.
8. A RO concentrate water treatment process according to any of claims 3-7, characterized by further comprising a membrane reaction of a membrane Fenton systemThe method comprises the following steps of: by means of H2SO4And/or cleaning the inner membrane of the membrane reaction tank by hydrogen peroxide.
9. A RO concentrate treatment process according to any of claims 3-7, characterized in that the quality of the feed water of the wastewater satisfies at least one of the following conditions: COD is less than or equal to 300 mg/L; the total nitrogen is less than or equal to 45 mg/L; total phosphorus is less than or equal to 5.0 mg/L; the alkalinity is less than or equal to 1800 mg/L; the hardness is less than or equal to 600.0 mg/L; the chloride ion is less than or equal to 4000 mg/L; the salt content is less than or equal to 15000 mg/L; the fluorine ion is less than or equal to 5.0 mg/L.
10. An automatic dosing method is characterized in that the flow and COD concentration of wastewater treated by the treatment method according to any one of claims 3 to 9 before entering a membrane Fenton system are detected on line, the dosing amount of a medicament is obtained according to an operational formula, and the Fenton medicament is dosed to the membrane Fenton system through an automatic dosing device.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115724501A (en) * | 2023-01-10 | 2023-03-03 | 生态环境部海河流域北海海域生态环境监督管理局生态环境监测与科学研究中心 | Process for treating high-salt organic wastewater by double electro-Fenton |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102249475A (en) * | 2010-05-18 | 2011-11-23 | 中国石油天然气股份有限公司 | Treatment method of membrane filtration concentrated solution |
| CN103145291A (en) * | 2011-12-06 | 2013-06-12 | 王炜 | Treatment process for zero discharge of double-membrane-method concentrated water |
| CN103755093A (en) * | 2013-12-13 | 2014-04-30 | 盐城工学院 | Fenton fluidized bed-IBAC combined method used for advanced treatment of textile dyeing and finishing waste water |
| CN108046458A (en) * | 2017-09-15 | 2018-05-18 | 中信环境技术（广州）有限公司 | The sewage water treatment method and system that a kind of membrane filtration is combined with Fenton oxidation |
| CN108996808A (en) * | 2018-07-02 | 2018-12-14 | 山西太钢不锈钢股份有限公司 | The biochemical combined treatment process and equipment of steel and iron industry concentrated water difficult to degrade |
| CN109111051A (en) * | 2018-09-29 | 2019-01-01 | 南京万德斯环保科技股份有限公司 | A kind of MSW landfill leachate regulating processing method and system |
| CN209493459U (en) * | 2019-01-31 | 2019-10-15 | 清华大学深圳研究生院 | A kind of dyeing waste water advanced treatment device |
| CN112551695A (en) * | 2020-12-11 | 2021-03-26 | 浙江清华长三角研究院 | Method for treating pharmaceutical wastewater by hydrolytic acidification-BAF-BAC combined process |
-
2021
- 2021-11-17 CN CN202111364226.6A patent/CN114212946A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102249475A (en) * | 2010-05-18 | 2011-11-23 | 中国石油天然气股份有限公司 | Treatment method of membrane filtration concentrated solution |
| CN103145291A (en) * | 2011-12-06 | 2013-06-12 | 王炜 | Treatment process for zero discharge of double-membrane-method concentrated water |
| CN103755093A (en) * | 2013-12-13 | 2014-04-30 | 盐城工学院 | Fenton fluidized bed-IBAC combined method used for advanced treatment of textile dyeing and finishing waste water |
| CN108046458A (en) * | 2017-09-15 | 2018-05-18 | 中信环境技术（广州）有限公司 | The sewage water treatment method and system that a kind of membrane filtration is combined with Fenton oxidation |
| CN108996808A (en) * | 2018-07-02 | 2018-12-14 | 山西太钢不锈钢股份有限公司 | The biochemical combined treatment process and equipment of steel and iron industry concentrated water difficult to degrade |
| CN109111051A (en) * | 2018-09-29 | 2019-01-01 | 南京万德斯环保科技股份有限公司 | A kind of MSW landfill leachate regulating processing method and system |
| CN209493459U (en) * | 2019-01-31 | 2019-10-15 | 清华大学深圳研究生院 | A kind of dyeing waste water advanced treatment device |
| CN112551695A (en) * | 2020-12-11 | 2021-03-26 | 浙江清华长三角研究院 | Method for treating pharmaceutical wastewater by hydrolytic acidification-BAF-BAC combined process |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115724501A (en) * | 2023-01-10 | 2023-03-03 | 生态环境部海河流域北海海域生态环境监督管理局生态环境监测与科学研究中心 | Process for treating high-salt organic wastewater by double electro-Fenton |
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