CN111285491A - Concentrated water treatment method and treatment device - Google Patents
Concentrated water treatment method and treatment device Download PDFInfo
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- CN111285491A CN111285491A CN201811496879.8A CN201811496879A CN111285491A CN 111285491 A CN111285491 A CN 111285491A CN 201811496879 A CN201811496879 A CN 201811496879A CN 111285491 A CN111285491 A CN 111285491A
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- C02F9/00—Multistage treatment of water, waste water or sewage
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- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/001—Processes for the treatment of water whereby the filtration technique is of importance
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- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
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- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/66—Treatment of water, waste water, or sewage by neutralisation; pH adjustment
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- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
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- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/72—Treatment of water, waste water, or sewage by oxidation
- C02F1/78—Treatment of water, waste water, or sewage by oxidation with ozone
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- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F2001/007—Processes including a sedimentation step
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- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
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- C02F2101/30—Organic compounds
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- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
- C02F2103/34—Nature of the water, waste water, sewage or sludge to be treated from industrial activities not provided for in groups C02F2103/12 - C02F2103/32
- C02F2103/36—Nature of the water, waste water, sewage or sludge to be treated from industrial activities not provided for in groups C02F2103/12 - C02F2103/32 from the manufacture of organic compounds
- C02F2103/365—Nature of the water, waste water, sewage or sludge to be treated from industrial activities not provided for in groups C02F2103/12 - C02F2103/32 from the manufacture of organic compounds from petrochemical industry (e.g. refineries)
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- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/08—Chemical Oxygen Demand [COD]; Biological Oxygen Demand [BOD]
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- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/10—Solids, e.g. total solids [TS], total suspended solids [TSS] or volatile solids [VS]
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/20—Total organic carbon [TOC]
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2301/00—General aspects of water treatment
- C02F2301/08—Multistage treatments, e.g. repetition of the same process step under different conditions
Abstract
The invention provides a treatment method and a treatment device for concentrated water, and relates to a wastewater treatment technology in the refining industry. The treatment method of the concentrated water comprises the following steps: carrying out primary ozone oxidation on the concentrated water to be treated to obtain primary oxidation concentrated water; adjusting the pH value of the first-stage oxidation concentrated water, adding a coagulant into the first-stage oxidation concentrated water for coagulation and precipitation, and taking supernatant for active sand filtration to obtain active sand filtration concentrated water; carrying out secondary ozone oxidation on the active sand filtration concentrated water to obtain tail gas and secondary oxidation concentrated water; carrying out primary ozone oxidation on the concentrated water to be treated by the tail gas; and carrying out biochemical treatment on the secondary oxidation concentrated water to obtain external drainage and discharging. The treatment method provided by the invention is particularly suitable for treating the thick water generated in the oil refining industry (including blending the inferior crude oil such as thick oil, super thick oil and the like) and the coal chemical industry, can quickly and non-selectively oxidize and treat various complex pollutants in the wastewater, and finally obtains the effluent meeting the requirements of relevant standards.
Description
Technical Field
The invention relates to a treatment method and a treatment device for concentrated water, in particular to a treatment method and a matched treatment device for high-salinity concentrated water after nanofiltration and/or reverse osmosis of wastewater in the refining industry.
Background
With the application of nanofiltration and reverse osmosis membranes in the advanced treatment process of wastewater in the refining industry, organic matters and salt are concentrated into the residual 20-30% of concentrated water while circulating cooling water replenishing water or boiler water with the total amount of 70-80% is obtained. The organic substances are mostly polycyclic aromatic hydrocarbons, heterocycles, chlorinated aromatics, phenols, cresol compounds and organic cyanides which are extremely difficult to degrade, not only have complex composition, but also have poor biodegradability, and the BOD/COD ratio is generally less than 0.2. Along with the gradual deterioration of processed oil products, such as blending of thick oil and ultra-thick oil, the composition of organic matters in produced wastewater is more complex and is more difficult to degrade, and the COD in the concentrated water can reach up to 300mg/L, which is about 2 times of the COD of the conventional concentrated water. If concentrated water is diluted and discharged, the water consumption per ton of oil is increased; if the concentrated water is directly returned to the front sewage treatment system, the concentrated water will have adverse effects on a biochemical system and the like. In order to reach the limit (COD is less than or equal to 50mg/L) in GB31570 one 2015 emission Standard of pollutants for oil refining industry, the concentrated water needs further advanced treatment.
At present, aiming at concentrated water in the refining and chemical industry, the existing feasible treatment modes mainly comprise a conventional oxidation method and an ozone catalytic oxidation method:
the conventional oxidation method is generally combined with a membrane method, and firstly an oxidant and a precipitator are added for treatment, then secondary reverse osmosis treatment is carried out, and finally secondary reverse osmosis concentrated water is discharged after oxidation treatment, which can be specifically referred to the scheme described in CN 106219816A. However, saline-alkali soil is easily generated if the salt in the discharged wastewater is directly discharged into the ecological environment after being concentrated, and in a high-salt environment, the second-level reverse osmosis concentrated water is low in oxidation rate and high in energy consumption in the oxidation process. CN 106746131A is to make organic waste water undergo the process of first-stage reverse osmosis treatment, after the concentrated waste water is oxidized, the oxidized waste water is passed through the action of softening agent, coagulant and coagulant aid to obtain supernatant liquor, after the supernatant liquor is neutralized, it is passed through the processes of multi-medium filtration, ultrafiltration and second-stage reverse osmosis to obtain second-stage concentrated water and reuse water. However, the subsequent treatment of the secondary concentrated water is a difficult problem, and the whole process increases the problem of fouling of the membrane system.
The catalytic ozonation method can be divided into a pure catalytic ozonation method and a further combined biological method. For example, CN 102070238A describes that the reverse osmosis concentrated water of the oil refining wastewater is treated by an ozone catalytic oxidation process at normal temperature and normal pressure, and after being homogenized by a regulating tank, the reverse osmosis concentrated water is subjected to an ozone catalytic oxidation reaction, and the effluent reaches the standard and is discharged outside. CN106467345A discloses a device for reverse osmosis concentrated water, which comprises a catalytic oxidation tank, an oxidation stabilization tank, a post-biochemical aeration biological filter and the like. Although the ozone catalytic oxidation method can increase the amount of recyclable water, the problem of treatment of super-concentrated sewage is easily increased. In addition, the ozone catalytic oxidation method has the problems of large ozone consumption, certain catalyst loss and waste.
In addition, various catalytic oxidation and other regulation means are combined, for example, CN 106045144A discloses a pretreatment method for reverse osmosis concentrated water by evaporation, that is, ozone oxidation, electrochemical oxidation, coagulant precipitation and filtration treatment are performed on the reverse osmosis concentrated water. Due to the combined use of a plurality of oxidation methods, reaction systems are different, the operation is complex, the energy consumption is high, and the cost of water treatment per ton is increased.
Therefore, the existing treatment means mostly aim at seawater, brackish water, coal chemical industry wastewater or general membrane concentrated water, the refining high-salt-content concentrated water of poor crude oil such as blended thick oil, super thick oil and the like which have complex components and are extremely difficult to treat is rarely involved, and the effluent index mostly aims at COD, and the other indexes specified in GB31570-2015 standard are rarely involved. Therefore, a treatment process for refining high-salt-content concentrated water aiming at poor crude oil such as blended thick oil, super thick oil and the like is developed, and the effluent index meets the relevant regulations in GB31570-2015, so that the treatment process has more practical significance for the current refining industry.
Disclosure of Invention
Aiming at the defects in the prior art, the invention provides a treatment method of concentrated water, which can effectively treat the refined high-salt-content concentrated water of inferior crude oil such as blended thick oil, super-thick oil and the like, and ensure that the effluent index meets the relevant standard regulation.
The invention provides a method for purifying refinery waste water, which comprises the method for treating concentrated water and can realize effective purification of the refinery waste water.
The invention also provides a treatment device for the concentrated water, which has a simple and reasonable structure and can realize effective treatment of the concentrated water.
In order to achieve the above object, a first aspect of the present invention provides a method for treating concentrated water, comprising the steps of:
carrying out primary ozone oxidation on the concentrated water to be treated to obtain primary oxidation concentrated water;
adjusting the pH value of the primary oxidation concentrated water to 9-11.5, adding a coagulant into the primary oxidation concentrated water for coagulation and precipitation, and taking supernatant for active sand filtration to obtain active sand filtration concentrated water;
carrying out secondary ozone oxidation on the active sand filtration concentrated water to obtain secondary oxidation concentrated water and tail gas;
carrying out primary ozone oxidation on the concentrated water to be treated by the tail gas;
and carrying out biochemical treatment on the secondary oxidation concentrated water to obtain external drainage and discharging.
According to the method for treating the concentrated water, firstly, residual ozone in tail gas is used for carrying out primary ozone pre-oxidation on the concentrated water to oxidize and decompose organic matters and other reducing substances which are easy to be oxidized in the concentrated water, so that the Chemical Oxygen Demand (COD) of the concentrated water is reduced preliminarily; then carrying out coagulation sedimentation under the condition of specific pH value, fully removing soluble substances, colloids and suspended matters in the concentrated water under the coagulation assisting action of a coagulant, and further removing the residual suspended matters through subsequent active sand filtration; secondly, the residual organic matters are oxidized and decomposed or converted into ozonization intermediate products through high-concentration two-stage ozone secondary oxidation; finally, the Organic pollutants and the like in a dissolved state in the concentrated water are converted into harmless substances through biochemical treatment, so that the discharged water meeting the requirements of GB31570 one-step 2015 emission Standard of pollutants for Petroleum refining industry is finally obtained, and indexes such as COD (chemical oxygen demand), Total Organic Carbon (TOC) content and Suspended Solid (SS) content and the like all meet the requirements of the standards.
In the above treatment process, because the ozone oxidation treatment is carried out twice, the organic matters which are easy to be oxidized and the organic pollutants which are relatively difficult to be oxidized are respectively removed or converted in the two ozone oxidation treatment processes, so that the effective removal of the organic pollutants is ensured, and the residual ozone in the tail gas is fully utilized. Especially, before the second ozone oxidation treatment, the hardness removal measures of the two steps of coagulating sedimentation and active sand filtration are adopted in advance, so that soluble substances, colloid, suspended matters and the like in the concentrated water are sufficiently removed, the mineralization degree of the concentrated water is sufficiently reduced, the suspended matters are removed, the interference of the substances on the ozone oxidation can be avoided, the organic matters are sufficiently converted, the full utilization of ozone is realized, and the utilization rate of the ozone is improved.
And because the pH value is adjusted to the optimal range before the second ozone oxidation treatment is carried out, active hydroxyl is rapidly generated in the second ozone oxidation process, the ozone hydroxylation direction is guided to be carried out, organic pollutants which cannot be biodegraded originally are converted into biodegradable organic matters, the biodegradability of the concentrated water is improved, and various organic pollutants in the concentrated water can be finally treated in an unselective manner.
In addition, because the effective removal of soluble substances, colloids, suspended matters and the like is realized before the second ozone oxidation, the phenomenon of scale formation and hardening which often occur in the ozone oxidation equipment such as the existing ozone catalytic oxidation tower and other treatment equipment under the high-salt environment due to long-term work is avoided, and the problem that the existing membrane concentrated water treatment device is difficult to normally operate is solved.
Waste water produced in oil refining industry and coal chemical industry (the invention is called as refined waste water) is treated by a reverse osmosis membrane and/or a nanofiltration membrane to obtain about 70-80% of standard water, the standard water can be used as desalted water for steam production of a boiler or as circulating cold water, and most organic matters and salt are intercepted to the side of concentrated water. Unless otherwise specified, the "concentrated water" in the present invention refers to concentrated water obtained by treating wastewater generated in the oil refining industry and the coal chemical industry with a reverse osmosis membrane and/or a nanofiltration membrane. For example, the concentrated water obtained after the oil refining wastewater is treated by the reverse osmosis membrane can be called reverse osmosis concentrated water, and the concentrated water obtained after the nanofiltration treatment can be called nanofiltration concentrated water.
The treatment method provided by the invention is particularly suitable for high-salt-content high-COD concentrated water, in particular to membrane concentrated water with the mineralization degree of more than or equal to 5000mg/L and the chemical oxygen demand of more than or equal to 100 mg/L. For example, poor crude oil such as blended thick oil and super thick oil which have complex components and are extremely difficult to treat is refined high-salt and high-COD concentrated water, the mineralization degree of the concentrated water is generally 5000-10000mg/L, COD and is generally 100-300 mg/L.
Specifically, the primary ozone oxidation can be performed in a concentrated water collecting tank, and specifically, gas containing ozone or ozone can be introduced into the concentrated water collecting tank, so that organic matters which are easily oxidized in the concentrated water to be treated can be oxidized and decomposed.
As a preferred embodiment of the invention, the tail gas discharged in the secondary ozone oxidation process can be subjected to primary ozone treatment on the concentrated water to be treated to obtain primary oxidation concentrated water, wherein the concentration of ozone in the tail gas is 1-10mg/L, and the time of primary ozone oxidation is 5-30 min.
Specifically, the tail gas can be introduced into the concentrated water collecting tank, so that the ozone can be fully utilized, the effective utilization rate of the ozone is increased, the stirring homogenizing effect is achieved, and the air volume of normal ventilation stirring is reduced.
Specifically, before coagulation and precipitation, an alkaline substance can be added into the primary oxidation concentrated water to adjust the pH value of the primary oxidation concentrated water to 9-11.5 so as to enhance the precipitation effect and be beneficial to quickly generating active hydroxyl in the subsequent secondary ozone oxidation process.
In some examples of the present invention, the alkaline substance used may be one or a combination of two or more of sodium hydroxide, calcium hydroxide, potassium hydroxide, sodium carbonate, and the like. Usually, an alkaline solution with the mass concentration of about 5-10% can be prepared in an alkaline solution storage box, and then the alkaline solution is added into the primary oxidation concentrated water, wherein the adding amount is about 1-4 per mill of the mass of the primary oxidation concentrated water, so that the pH value of the primary oxidation concentrated water can reach 9-11.5.
The coagulant used in the coagulation and precipitation process is not particularly limited, and may be, for example, one or a combination of two or more of the coagulants commonly used in the concentrated water treatment process at present, including but not limited to ferrous sulfate, polyaluminum chloride, polyaluminum ferric chloride, aluminum sulfate, ferric chloride, and the like, which have a good coagulation effect.
Specifically, a coagulant aqueous solution with the mass concentration of about 5-10% can be prepared in a coagulant storage box, and then the coagulant aqueous solution is added into the first-stage oxidation concentrated water, wherein the adding amount is about 5-25mg/L, namely, about 5-25mg of coagulant aqueous solution is added into every 1L of first-stage oxidation concentrated water.
The coagulation and sedimentation treatment may be carried out in a flocculation sedimentation device, and preferably, the flocculation sedimentation device is one selected from among horizontal sedimentation tanks, inclined tube (plate) sedimentation tanks, vertical sedimentation tanks, radial sedimentation tanks and other effective sedimentation devices. After coagulation and sedimentation treatment, the generated sediment can be discharged into a sludge concentration tank, and the obtained supernatant can be subjected to subsequent active sand filtration.
Specifically, the active sand filtration can be carried out in an active sand filter, and the supernatant can pass through a water distribution pipe and a quartz sand filter material with the diameter of 1-3mm from bottom to top, so that the residual suspended matters in the supernatant can be further removed, and the secondary ozone oxidation treatment of the obtained active sand filtration concentrated water is favorably carried out; and the turbid water discharged from the active sand filter can enter a backwashing water tank, and after a certain amount of liquid in the backwashing water tank is accumulated, the turbid water can be merged into the concentrated water to be treated for primary ozone oxidation, for example, the liquid in the backwashing water tank can be transferred into a concentrated water treatment tank through a pipeline.
In some examples of the invention, the secondary ozonation is carried out in an ozone catalytic oxidation tower (also referred to as an ozone reactor, an ozone mixing tower, an ozone dosing device, etc.). Different from the mode of countercurrent contact of ozone and concentrated water in the prior art, the invention preferably enables the active sand filtration concentrated water and the ozone to enter from the bottom of the ozone catalytic oxidation tower, the finally obtained tail gas to be discharged from the outlet at the top of the ozone catalytic oxidation tower, and the obtained secondary oxidation concentrated water to be discharged from the outlet at the upper part of the ozone catalytic oxidation tower. Compared with a countercurrent contact mode, the contact mode in the embodiment of the invention can prolong the reaction time, improve the removal rate of organic matters and the utilization rate of ozone, and simultaneously can avoid the problem that the existing gas-liquid countercurrent contact is easy to cause flooding.
In a preferred embodiment of the invention, the ratio of the total mass of the added ozone to the total mass of the organic matters in the active sand filtration concentrated water in terms of chemical oxygen demand is 1-5: 1, the space velocity is 0.5 to 5h-1The contact reaction time of the ozone and the active sand filtration concentrated water is 30-60min, the hydraulic retention time is 60-150min, and the temperature of the active sand filtration concentrated water is controlled at 15-30 ℃. The catalytic oxidation of ozone is carried out under the condition, so that the ozone can fully react with organic matters, and the organic matters which cannot be biodegraded originally are fully converted into biodegradable organic matters, thereby being beneficial to the implementation of subsequent biochemical treatment.
It can be understood that adding a proper catalyst in the ozone oxidation process can generate obvious catalytic effect on the ozone oxidation. In some examples of the invention, the ozone catalytic oxidation tower is filled with an aluminum-based catalyst, and the volume of the aluminum-based catalyst accounts for 50-90% of the total volume of the ozone catalytic oxidation tower;
in the aluminum-based catalyst, the mass content of aluminum oxide is 24-45%, the mass content of copper oxide is 15-45%, the mass content of manganese oxide is 10-30%, the mass content of nickel oxide is 5-20%, and the balance is at least one of iron oxide, titanium oxide, zinc oxide and cerium oxide, wherein the total mass content of iron oxide, titanium oxide, zinc oxide and cerium oxide is generally 1-5% of the total mass of the aluminum-based catalyst.
Further, the porosity of the aluminum-based catalyst is 45 to 75%.
Further, the number of the above-mentioned catalytic ozonation towers is preferably two or more, and a plurality of catalytic ozonation towers are connected in series. Specifically, the active sand filtered concentrated water can be subjected to secondary ozone oxidation in one ozone catalytic oxidation tower, and the obtained oxidation product enters the next ozone catalytic oxidation tower to continue the secondary ozone oxidation so as to ensure that organic matters are fully oxidized; in the process, the tail gas discharged by each ozone catalytic oxidation tower is collected and introduced into the concentrated water collecting tank for secondary absorption and utilization of residual ozone in the tail gas.
The secondary oxidation concentrated water obtained by the secondary ozone oxidation can be subjected to biochemical treatment. In some examples of the invention, during the biochemical treatment, the ratio of biochemical oxygen demand: nitrogen source: the phosphorus source is (95-110): (3-8): (0.5-1.3) adding a nutrient source into the secondary oxidation concentrated water, and controlling the dissolved oxygen of the secondary oxidation concentrated water to be 4-6mg/L and the water temperature to be 15-30 ℃.
In the practice of the present invention, the biochemical oxygen demand is generally: nitrogen source: the phosphorus source is 100: 5: 1, adding a nutrient source into the secondary oxidation concentrated water, wherein the nitrogen source can be urea specifically, and the phosphorus source can be sodium phosphate or disodium hydrogen phosphate specifically.
Biochemical Oxygen Demand (BOD), also known as Biochemical Oxygen Demand, is also commonly written as "BOD 5" because the industry currently refers to five-day Biochemical Oxygen Demand.
Specifically, the secondary oxidation concentrated water can be subjected to biochemical treatment in the biological aerated filter. As a preferred embodiment, the biological aerated filter can be filled with biological ceramsite, the main component of the biological ceramsite is aluminosilicate, and the specific surface area can be specifically 4 multiplied by 104-8×104cm2The biological ceramsite with the surface area is suitable for the attachment, fixation and growth of microorganisms, so that the biological ceramsite has strong biological oxidation capacity. The filling amount of the biological ceramsite can specifically account for 30-60% of the total volume of the secondary oxidation concentrated water.
After the biochemical treatment is arranged in the ozone oxidation twice, because the biological ceramsite has the interception effect on SS, microorganisms in the biological ceramsite have the further degradation effect on COD and have the effect of carrying out stable homogenization on the early-stage oxidation effluent, and therefore, the biochemical treatment can play a dual control role on COD and SS in the effluent.
By implementing the series of treatments, the COD, TOC, SS and oil content of the finally obtained external drainage can reach the relevant regulations in GB 31570-2015.
In a second aspect, the present invention provides a method for purifying refinery waste water, comprising the steps of:
treating the refining wastewater by adopting a reverse osmosis membrane and/or a nanofiltration membrane to obtain standard water and concentrated water;
according to the treatment method provided by the first aspect, concentrated water is treated.
As mentioned above, the refining wastewater may be wastewater generated in oil refining industry and coal chemical industry, especially wastewater generated in the process of refining poor crude oil such as heavy oil, super heavy oil and the like with complex and extremely difficult processing components, and the wastewater is processed by a reverse osmosis membrane and/or a nanofiltration membrane to obtain about 70-80% of water reaching standards, which can be used as desalted water for steam generation of boilers or as recycled cold water, and most of organic matters and salts are concentrated in the concentrated water.
The process conditions for the reverse osmosis membrane treatment and the nanofiltration membrane treatment are not particularly limited, and the treatment can be carried out by the methods described in the prior art.
By carrying out the treatment on the concentrated water, the obtained discharged water meets the relevant regulations in the national standard GB31570-2015, so that the discharged water can directly reach the standard and be discharged.
The third aspect of the present invention provides a membrane concentrated water treatment apparatus, which is used in the treatment method of the first aspect, and comprises a concentrated water collecting tank, a flocculation precipitation device, an active sand filter, an ozone catalytic oxidation tower, and a biological aerated filter, which are connected in sequence, wherein:
the concentrated water collecting tank is used for carrying out primary ozone oxidation on membrane concentrated water to be treated and is provided with a gas inlet;
the flocculation precipitation equipment is used for implementing coagulation and precipitation on the first-stage oxidation concentrated water;
the active sand filter is used for filtering the supernatant by active sand;
the ozone catalytic oxidation tower is used for carrying out secondary ozone oxidation on the active sand filtration concentrated water, and a gas outlet of the ozone catalytic oxidation tower for discharging tail gas is connected with a gas inlet of the concentrated water collecting tank;
the aeration biological filter is used for carrying out biochemical treatment on the secondary oxidation concentrated water.
Specifically, the concentrated water to be treated can be introduced into a concentrated water collecting tank, and ozone or gas containing ozone is introduced into the concentrated water collecting tank so as to carry out primary ozone oxidation on the concentrated water, oxidize and decompose organic matters and other reducing substances which are easy to be oxidized in the concentrated water, and preliminarily reduce the COD of the membrane concentrated water to obtain primary oxidation concentrated water; then the first-stage oxidation concentrated water is led into a flocculation precipitation device, the pH value of the first-stage oxidation concentrated water is adjusted to 9-11.5, and then a coagulant is added and precipitation is carried out, so that the soluble substances, colloids and suspended matters in the first-stage oxidation concentrated water are fully removed; enabling the supernatant in the flocculation precipitation equipment to enter an active sand filter, and further removing residual suspended matters in the supernatant to obtain active sand filtering concentrated water; and (3) introducing the active sand filtered concentrated water into an ozone catalytic oxidation tower for secondary ozone oxidation, then introducing the obtained secondary oxidized concentrated water into an aeration biological filter for biochemical treatment, and introducing the obtained tail gas into a concentrated water collecting tank for recycling.
Specifically, the concentrated water collecting tank, the flocculation precipitation equipment, the active sand filter, the ozone catalytic oxidation tower and the biological aerated filter can be connected through pipelines. Wherein, can be connected with the first pump body between dense water collecting pit and the flocculation and precipitation equipment, can be connected with the second pump body between flocculation and precipitation equipment and the active sand filter, can be connected with the third pump body between active sand filter and the ozone catalytic oxidation tower to the liquid flow of each processing link of accurate control.
The flocculation and sedimentation equipment used in some examples of the invention may be, for example, a horizontal sedimentation tank, a sloped tube (plate) sedimentation tank, a vertical sedimentation tank, a radial sedimentation tank, or other effective sedimentation equipment.
Furthermore, the flocculation precipitation equipment can be connected with an alkali liquor storage box and a coagulant storage box, wherein the alkali liquor storage box is used for preparing an alkaline aqueous solution, and the prepared alkaline aqueous solution can be added into the flocculation precipitation equipment to adjust the pH value of the first-stage oxidation concentrated water; the coagulant storage box is used for preparing coagulant aqueous solution and then is added into the flocculation precipitation equipment.
Furthermore, the flocculation precipitation equipment can be connected with a sludge concentration tank to collect solid precipitates generated in the coagulation and precipitation processes.
Further, the treatment device especially comprises at least two ozone catalytic oxidation towers which are connected in series to improve the secondary ozone oxidation effect.
Furthermore, the gas outlet at the top of each ozone catalytic oxidation tower can be connected with the gas inlet of the concentrated water collecting tank, so that the tail gas discharged from the ozone catalytic oxidation tower is introduced into the concentrated water to be treated, and primary ozone oxidation is carried out, thereby realizing full and effective utilization of ozone.
Furthermore, the active sand filter and the biological aerated filter can be connected with a backwashing water tank; still further, the backwash water tank can also be connected with a concentrated water collection tank. The backwashing water tank is used for collecting turbid water discharged from the active sand filter and collecting backwashing water generated in the biological aerated filter. When the liquid in the backwashing water tank reaches a certain degree, the turbid water and the backwashing water can be transferred into the concentrated water treatment tank for primary ozone oxidation, so that the whole treatment device is free from harmful wastewater discharge.
The treatment method of the concentrated water provided by the invention has the following advantages:
1. the treatment method can be used for treating the concentrated water generated in the oil refining industry (including poor crude oil such as blended thick oil, super thick oil and the like) and the coal chemical industry, and can quickly and non-selectively oxidize and treat various complex organic pollutants, inorganic salts and the like in the concentrated water, so that the COD value of the reverse osmosis concentrated water and the nanofiltration concentrated water with the COD of 100-300mg/L can reach the requirements specified in the GB31570-2015 standard.
2. The procedures in the whole treatment process are reasonably arranged, wherein: the hardness removal by coagulating sedimentation fully reduces the mineralization degree in the concentrated water and removes suspended matters, reduces the influence of inorganic salt and the suspended matters on the subsequent catalytic oxidation effect of ozone, reduces the blockage of salt which is easy to scale in the concentrated water to catalyst micropores, avoids the problem of scale hardening, and promotes the utilization rate and the oxidation efficiency of the ozone; the optimization of pH promotes the catalytic oxidation process of ozone to rapidly generate active hydroxyl, guides the hydroxylation direction of ozone to be carried out, and indiscriminately treats various organic pollutants in the wastewater; after two times of ozone oxidation catalysis, biochemical treatment is carried out, COD and SS of the external drainage water play a role in dual control, and finally indexes such as TOC, oil content and SS in the external drainage water can meet the standard requirements of GB 31570-2015.
3. The tail gas obtained by secondary ozone oxidation is used for carrying out primary ozone oxidation on the concentrated water, so that the effective utilization rate of ozone is increased, the effect of stirring homogenization is achieved, and the air volume of normal ventilation stirring is reduced.
The device for treating the concentrated water provided by the invention adopts conventional equipment, has a simple structure and reasonable layout, and can ensure effective treatment of the concentrated water, so that indexes such as COD, TOC, oil content and SS of finally obtained discharged water can meet the standard requirement of GB 31570-2015.
The method for purifying the refinery waste water can be adjusted on the basis of the existing refinery waste water purification process, can realize effective purification of the refinery waste water, and avoids discharge of harmful waste water.
Drawings
FIG. 1 is a schematic process flow diagram of the treatment method of concentrated water with high salt content after membrane refining.
Description of reference numerals:
1-concentrated water collecting tank; 2-flocculation precipitation equipment;
3-an active sand filter; 4-an ozone catalytic oxidation tower;
5-aeration biological filter; 6-backwashing the water tank;
7-sludge concentration tank; 8-alkali liquor storage box;
9-coagulant storage tank; 10-a first pump body;
11-a second pump body; 12-third pump body.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The embodiment provides a membrane concentrated water treatment device, please refer to fig. 1, which includes a concentrated water collecting tank 1, a flocculation and precipitation device 2, an active sand filter 3, an ozone catalytic oxidation tower 4 and a biological aerated filter 5, which are connected in sequence through a transmission pipeline.
Specifically, the concentrated water to be treated can be introduced into the concentrated water collecting tank 1, and ozone or ozone-containing gas is introduced into the concentrated water collecting tank 1, so that the concentrated water to be treated is subjected to primary ozone oxidation to oxidize and decompose reducing substances such as easily-oxidized organic substances in the concentrated water, and the COD of the concentrated water is primarily reduced to obtain primary oxidized concentrated water; then leading the first-stage oxidation concentrated water into a flocculation precipitation device 2, adjusting the pH value of the first-stage oxidation concentrated water to 9-11.5, then adding a coagulant into the flocculation precipitation device 2, and fully removing soluble substances, colloids and suspended matters in the first-stage oxidation concentrated water after precipitation; enabling the supernatant in the flocculation precipitation equipment 2 to enter an active sand filter 3, and enabling the supernatant to pass through a quartz sand filter material with the diameter of 1-3mm from bottom to top, so as to further remove residual suspended matters in the supernatant and obtain active sand filtering concentrated water; and (3) introducing the active sand filtered concentrated water into an ozone catalytic oxidation tower 4 for secondary ozone oxidation, introducing the obtained tail gas into a concentrated water collecting tank 1, and then introducing the obtained secondary oxidized concentrated water into an aeration biological filter 5 for biochemical treatment to finally obtain the discharged water meeting the standard.
With further reference to fig. 1, the activated sand filter 3 and the biological aerated filter 5 can also be connected to a backwash water tank 6, and the backwash water tank 6 can also be connected to a concentrated water collection tank 1, so that the turbid water discharged from the activated sand filter 3 and the backwash water generated in the biological aerated filter 5 can enter the backwash water tank 6, and when the liquid in the backwash water tank 6 reaches a certain degree, the liquid can enter the concentrated water treatment tank 1 to be subjected to primary ozone oxidation, thereby realizing that the whole treatment device has no harmful wastewater discharge.
With further reference to fig. 1, the flocculation and sedimentation device 2 may also be connected to a sludge thickening tank 7 for collecting solid sediment produced during coagulation and sedimentation.
Referring further to fig. 1, the flocculation and precipitation equipment 2 is connected with an alkali liquor storage tank 8 and a coagulant storage tank 9, wherein the alkali liquor storage tank 8 is used for preparing an alkaline aqueous solution, and the prepared alkaline aqueous solution is added into the flocculation and precipitation equipment 2 to adjust the pH value of the first-stage oxidation concentrated water; the coagulant storage tank 9 is used for preparing coagulant aqueous solution, and then the coagulant aqueous solution is added into the flocculation precipitation equipment 2.
With further reference to fig. 1, a first pump body 10 is connected between the concentrated water collecting tank 1 and the flocculation and precipitation device 2, a second pump body 11 is connected between the flocculation and precipitation device 2 and the active sand filter 3, and a third pump body 12 is connected between the active sand filter 3 and the ozone catalytic oxidation tower 4.
Further, the number of the above-mentioned ozone catalytic oxidation towers 4 is preferably two or more, and the following examples will be described in detail by taking two ozone catalytic oxidation towers 4 as examples.
In the specific implementation process of this embodiment, the mineralization degree of the concentrated water to be treated is 5000-10000mg/L, COD-100-300 mg/L, and the detailed process of treating the concentrated water is as follows:
s1, the concentrated water stays in the concentrated water collecting pool 1 for 5-30min, and a small amount of easily oxidized COD substances are removed preliminarily under the action of one-time ozone oxidation of residual ozone (the concentration is about 1-10mg/L) in tail gas (the tail gas collected at the top of the two-stage ozone catalytic oxidation tower 4), so that first-stage oxidation concentrated water is obtained.
S2, enabling the primary oxidation concentrated water to enter a flocculation precipitation device 2, preparing an alkaline aqueous solution with the mass concentration of 5-10% in an alkaline liquid storage box 8, adding the alkaline aqueous solution into the primary oxidation concentrated water, wherein the adding amount is about 1-4 per mill of the mass of the primary oxidation concentrated water, and adjusting the pH value of the primary oxidation concentrated water to 9-11.5;
preparing a coagulant aqueous solution with the mass concentration of 5-10% in a coagulant storage box 9, adding 5-25mg/L of primary oxidation concentrated water, removing soluble substances, colloids and suspended matters in the primary oxidation concentrated water under the coagulation assisting action of the coagulant, and feeding the water into a sludge concentration tank 7 in the form of precipitates;
supernatant produced in the flocculation precipitation equipment 2 enters an active sand filter 3 through a water distribution pipe, and further removes suspended matters in the supernatant through a quartz sand filter material with the diameter of 1-3mm from bottom to top to obtain active sand filtered concentrated water.
S3, enabling the active sand filtered concentrated water to enter the bottom of the two-stage ozone catalytic oxidation tower 4, simultaneously exposing ozone from the bottom of the ozone catalytic oxidation tower 4, discharging the two-stage oxidized concentrated water subjected to catalytic oxidation by the ozone from the upper part of the ozone catalytic oxidation tower 4, and introducing tail gas discharged from the top of the ozone catalytic oxidation tower 4 into a concentrated water collecting pool 1.
Wherein, the ratio of the total mass of the added ozone to the total mass of organic matters in the active sand filtration concentrated water by the chemical oxygen demand is 1-5: 1, the space velocity is 0.5 to 5h-1The contact reaction time of ozone and active sand filtration concentrated water is 30-60min, the hydraulic retention time is 60-150min, and the water is activatedControlling the temperature of the concentrated water for filtering the sand to be 15-30 ℃;
each ozone catalytic oxidation tower 4 is filled with an aluminum-based catalyst, and the volume of the aluminum-based catalyst accounts for 50-90% of the total volume of the ozone catalytic oxidation tower 4; in the aluminum-based catalyst, the mass content of aluminum oxide is 24-45%, the mass content of copper oxide is 15-45%, the mass content of manganese oxide is 10-30%, the mass content of nickel oxide is 5-20%, and the balance is at least one of iron oxide, titanium oxide, zinc oxide and cerium oxide; the porosity of the aluminum-based catalyst is 45-75%.
S4, the secondary oxidation concentrated water finally enters the biological aerated filter 5 for biochemical treatment to obtain external drainage which can reach the standard discharge. The turbid water from the active sand filter 3 and the backwashing water from the biological aerated filter 5 both enter a backwashing water tank 6, and the backwashing water accumulated to a certain amount is transferred into the concentrated water collecting tank 1 through a pipeline.
In the biochemical treatment process, the biochemical oxygen demand: nitrogen source: the phosphorus source is 100: 5: 1, adding a nutrient source into the secondary oxidation concentrated water, and controlling the dissolved oxygen of the secondary oxidation concentrated water to be 4-6mg/L and the water temperature to be 15-30 ℃. Biological ceramsite can be filled in the biological aerated filter 5, and the filling amount of the biological ceramsite accounts for 30-60% of the volume of the secondary oxidation concentrated water; the main component of the biological ceramsite is aluminosilicate with specific surface area of 4 multiplied by 104cm2G to 8X 104cm2/g。
Example 1
And (3) carrying out primary ozone oxidation on the refined nanofiltration concentrated water for 5min by using tail gas with residual ozone concentration of 1mg/L in a concentrated water collecting tank 1 to obtain primary oxidation concentrated water, and then feeding the primary oxidation concentrated water into a horizontal flow type sedimentation tank.
Preparing a sodium hydroxide aqueous solution with the concentration of 10% in an alkali liquor storage box 8, adding the sodium hydroxide aqueous solution into first-stage oxidation concentrated water, and adjusting the pH to be about 9; preparing a coagulant ferrous sulfate aqueous solution with the concentration of 5% in a coagulant storage box 9, adding the coagulant aqueous solution with the concentration of 5mg/L, removing soluble substances, colloids and suspended matters in the primary oxidation concentrated water, filtering the obtained supernatant through active sand, and further reducing suspended matter particles in the supernatant to obtain the active sand filtered concentrated water.
The two-stage ozone catalytic oxidation tower 4 adopts a series connection mode, aluminum-based catalysts are filled in the two-stage ozone catalytic oxidation tower 4, and the filling amount (v/v) is 50%. The aluminum-based catalyst mainly comprises 45% of aluminum oxide, 30% of manganese oxide, 15% of copper oxide, 5% of nickel oxide and 5% of iron oxide; the porosity of the aluminum-based catalyst was 45%.
Active sand filtered concentrated water enters from the bottom of the ozone catalytic oxidation tower 4, obtained secondary oxidized concentrated water flows out from the upper part of the ozone catalytic oxidation tower 4, ozone is exposed from the bottom of the ozone catalytic oxidation tower 4, and obtained tail gas is discharged from the top of the ozone catalytic oxidation tower 4 and then enters the concentrated water collecting tank 1; the ratio of the total mass of the ozone to the total mass of COD in the active sand filtration concentrated water is 1: 1, the space velocity is 5h-1The contact reaction time of ozone and active sand filtration concentrated water is 30min, and the hydraulic retention time is 60 min.
The retention time of the secondary oxidation concentrated water in the biological aerated filter 5 is 4h, the biological aerated filter 5 is filled with biological ceramsite, the main component of the biological aerated filter is aluminosilicate, and the specific surface area is about 4 multiplied by 104cm2The addition amount of the biological ceramsite is 30 percent, and the biological ceramsite is prepared from the following raw materials in parts by weight of BOD 5: n: p is 100: 5: 1 adding a nutrient source, wherein the N source is urea, the P source is sodium phosphate, the dissolved oxygen is controlled to be 4mg/L, and the water temperature is 15 ℃. The detection results of the effluent quality are shown in the following table 1:
table 1 water quality analysis test results of example 1
Example 2
The original COD of a certain refined (blended super heavy oil) nanofiltration-reverse osmosis concentrated water is 300mg/L, the mineralization degree is 10000mg/L, and tail gas with the residual ozone concentration of 10mg/L is subjected to primary ozone oxidation for 30min in a concentrated water collecting tank 1 and then enters an inclined tube (plate) sedimentation tank.
Preparing a sodium hydroxide aqueous solution with the concentration of 10% in an alkali liquor storage box 8, adding the sodium hydroxide aqueous solution into the first-stage oxidation concentrated water, and adjusting the pH to be about 11.5; preparing a coagulant polyaluminium chloride aqueous solution with the concentration of 10% in a coagulant storage box 9, adding 25mg/L coagulant into the coagulant storage box, removing soluble substances, colloids and suspended matters in the primary oxidation concentrated water, filtering the obtained supernatant by using active sand, and further reducing suspended matter particles in the supernatant to obtain the active sand filtered concentrated water.
The two-stage ozone catalytic oxidation tower 4 adopts a series connection mode, the two-stage ozone catalytic oxidation tower 4 is filled with aluminum-based catalysts, and the filling amount (v/v) is 90%. The components of the aluminum-based catalyst are mainly alumina, 30 percent of manganese oxide, 22 percent of copper oxide, 15 percent of nickel oxide, 3 percent of titanium oxide and 75 percent of porosity.
Active sand filtration concentrated water enters from the bottom of the ozone catalytic oxidation tower 4, obtained secondary oxidation concentrated water flows out from the upper part of the ozone catalytic oxidation tower 4, ozone is exposed from the bottom of the ozone catalytic oxidation tower 4, and obtained tail gas is discharged from the top of the ozone catalytic oxidation tower 4 and then enters the concentrated water collecting tank 1; the ratio of the total mass of the added ozone to the total mass of COD in the active sand filtration concentrated water is 5: 1, the space velocity is 0.5h-1The contact reaction time of the ozone and the active sand filtration concentrated water is 60min, and the hydraulic retention time is 150 min.
The retention time of the secondary oxidation concentrated water in the biological aerated filter 5 is 4h, the biological aerated filter 5 is filled with biological ceramsite, the main component of the biological aerated filter is aluminosilicate, and the specific surface area is about 8 multiplied by 104cm2The addition amount of the biological ceramsite is 60 percent, according to the proportion of BOD 5: n: p is 100: 5: 1 adding a nutrient source, wherein the N source is urea, the P source is disodium hydrogen phosphate, the dissolved oxygen is controlled to be 6mg/L, and the water temperature is 30 ℃. The detection results of the effluent quality are shown in the following table 2:
table 2 water quality analysis test results of example 2
Example 3
After the initial COD of the reverse osmosis concentrated water of certain refining (blended thick oil) is 200mg/L and the mineralization degree is 7000mg/L, tail gas with the residual ozone concentration of 8mg/L is subjected to primary ozone oxidation for 10min in a concentrated water collecting tank 1 and then enters a vertical flow type sedimentation tank.
Preparing an alkaline aqueous solution in an alkaline solution storage box 8, wherein the concentrations of sodium hydroxide and calcium hydroxide are both 5%, and adding the alkaline aqueous solution into first-stage oxidation concentrated water to adjust the pH to about 10; coagulant aluminum sulfate and ferric trichloride are prepared in a coagulant storage box 9 (the mixing ratio is 1: 1, the preparation concentration is 8%), the adding concentration in a vertical flow sedimentation tank is 25mg/L, soluble substances, colloid and suspended matters in the primary oxidation concentrated water are removed, the obtained supernatant is filtered by active sand, and suspended matter particles in the supernatant are further reduced to obtain the active sand filtered concentrated water.
The two-stage ozone catalytic oxidation tower 4 adopts a series connection mode, aluminum-based catalysts are filled in the two-stage ozone catalytic oxidation tower 4, and the filling amount (v/v) is 50%. The aluminum-based catalyst mainly comprises 24 percent of aluminum oxide, 10 percent of manganese oxide, 45 percent of copper oxide, 20 percent of nickel oxide and 1 percent of zinc oxide; the porosity of the aluminum-based catalyst was 55%.
Active sand filtration concentrated water enters from the bottom of the ozone catalytic oxidation tower 4, obtained secondary oxidation concentrated water flows out from the upper part of the ozone catalytic oxidation tower 4, ozone is exposed from the bottom of the ozone catalytic oxidation tower 4, and obtained tail gas is discharged from the top of the ozone catalytic oxidation tower 4 and then enters the concentrated water collecting tank 1; the ratio of the total mass of the ozone to the total mass of COD in the active sand filtration concentrated water is 2.5: 1, the space velocity is 3h-1The contact reaction time of the ozone and the active sand filtration concentrated water is 40min, and the hydraulic retention time is 90 min.
The retention time of the secondary oxidation concentrated water in the biological aerated filter 5 is 4h, the biological aerated filter 5 is filled with biological ceramsite, the main component of the biological aerated filter is aluminosilicate, and the specific surface area is about 6 multiplied by 104cm2The addition amount of the biological ceramsite is 45 percent, and the biological ceramsite is prepared from the following raw materials in parts by weight of BOD 5: n: p is 100: 5: 1 adding a nutrient source, wherein the N source is urea, the P source is disodium hydrogen phosphate, the dissolved oxygen is controlled to be 5mg/L, and the water temperature is 20 ℃. The detection results of the effluent quality are shown in the following table 3:
table 3 water quality analysis test results of example 3
Example 4
The initial COD of the nanofiltration-reverse osmosis concentrated water in coal chemical industry is 250mg/L, the mineralization is 8500mg/L, and tail gas with residual ozone concentration of 5mg/L is subjected to primary ozone oxidation in a concentrated water collection tank 1 for 20min and then enters a radiation type sedimentation tank.
Preparing an alkaline aqueous solution in an alkaline solution storage box 8, wherein the concentrations of potassium hydroxide and sodium carbonate are both 4%, and adding the alkaline aqueous solution into primary oxidation concentrated water to adjust the pH value to about 10; preparing polyaluminum ferric chloride in a coagulant storage box 9, wherein the preparation concentration is 8%, the adding concentration is 15mg/L, removing soluble substances, colloid and suspended matters in the primary oxidation concentrated water, filtering the obtained supernatant by using active sand, and further reducing suspended matter particles in the supernatant to obtain the active sand filtered concentrated water.
The two-stage ozone catalytic oxidation tower 4 adopts a series connection mode, aluminum-based catalysts are filled in the two-stage ozone catalytic oxidation tower 4, and the filling amount (v/v) is 70%. The aluminum-based catalyst mainly comprises 31% of aluminum oxide, 15% of manganese oxide, 40% of copper oxide, 10% of nickel oxide, 4% of cerium oxide and 65% of porosity.
Active sand filtration concentrated water enters from the bottom of the ozone catalytic oxidation tower 4, obtained secondary oxidation concentrated water flows out from the upper part of the ozone catalytic oxidation tower 4, ozone is exposed from the bottom of the ozone catalytic oxidation tower 4, and obtained tail gas is discharged from the top of the ozone catalytic oxidation tower 4 and then enters the concentrated water collecting tank 1; the ratio of the total mass of the ozone to the total mass of COD in the active sand filtration concentrated water is 4: 1, the space velocity is 2h-1The contact reaction time of the ozone and the active sand filtration concentrated water is 50min, and the hydraulic retention time is 120 min.
Aeration biological filter for secondary oxidation concentrated waterThe retention time in the tank 5 is 4h, the biological aerated filter 5 is filled with biological ceramsite, the main component of the biological aerated filter is aluminosilicate, and the specific surface area is about 7 multiplied by 104cm2The addition amount of the biological ceramsite is 50 percent, according to the proportion of BOD 5: n: p is 100: 5: 1 adding a nutrient source, wherein the N source is urea, the P source is sodium phosphate, the dissolved oxygen is controlled to be 6mg/L, and the water temperature is 25 ℃. The detection results of the effluent quality are shown in the following table 4:
table 4 water quality analysis test results of example 4
As can be seen from tables 1 to 4, the treatment method provided by the present invention is applied to the concentrated water listed in examples 1 to 4, the removal rate of COD reaches 90% or more, the oil content, TOC and CC are all significantly reduced, and the COD, oil content, TOC and SS of the external drainage can meet the requirements of GB31570-2015 "emission standard of pollutants for petroleum refining industry".
Comparative example 1
This comparative example provides a process for treating a concentrate which is identical to the refined nanofiltration concentrate of example 1, with an initial COD of 150mg/L and a degree of mineralization of 3000 mg/L. The specific treatment process comprises the following steps:
carrying out primary ozone oxidation treatment by adopting the process completely the same as that in the embodiment 1, directly feeding the obtained primary oxidation concentrated water into a two-stage ozone catalytic oxidation tower 4 for secondary ozone oxidation, wherein the process conditions of the secondary ozone oxidation treatment are completely the same as that in the embodiment 1, and obtaining secondary oxidation concentrated water;
the biochemical treatment of the secondary oxidation concentrated water was carried out under the same process conditions as in example 1, and the water quality test results of the obtained effluent were as shown in table 5 below.
Further comparing the water quality detection results in tables 1 and 5, the embodiment of the invention promotes the utilization rate and oxidation efficiency of ozone through reasonable arrangement of the operation of removing hardness by coagulating sedimentation and the operation of adjusting pH in the whole process.
TABLE 5 Water quality analysis and examination results of comparative example 1
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.
Claims (10)
1. A concentrated water treatment method is characterized by comprising the following steps:
carrying out primary ozone oxidation on the concentrated water to be treated to obtain primary oxidation concentrated water;
adjusting the pH value of the primary oxidation concentrated water to 9-11.5, adding a coagulant into the primary oxidation concentrated water for coagulation and precipitation, and taking supernatant for active sand filtration to obtain active sand filtration concentrated water;
carrying out secondary ozone oxidation on the active sand filtration concentrated water to obtain secondary oxidation concentrated water and tail gas;
the tail gas is used for carrying out primary ozone oxidation on the concentrated water to be treated;
and carrying out biochemical treatment on the secondary oxidation concentrated water to obtain external drainage and discharging.
2. The treatment method according to claim 1, wherein the membrane concentrate has a degree of mineralization of 5000mg/L or more and a chemical oxygen demand of 100mg/L or more.
3. The treatment method according to claim 1 or 2, wherein the concentration of ozone in the tail gas is 1-10mg/L, and the time of primary ozone oxidation is 5-30 min.
4. The treatment method according to claim 1 or 2, wherein the mass concentration of the coagulant is 5-10%, and the addition amount of the coagulant is 1-4% of the mass of the primary oxidation concentrated water.
5. The treatment method according to claim 1 or 2, wherein the secondary ozone oxidation is carried out in an ozone catalytic oxidation tower, so that the active sand filtration concentrated water and ozone enter from the bottom of the ozone catalytic oxidation tower, the obtained tail gas is discharged from the top of the ozone catalytic oxidation tower, and the obtained secondary oxidation concentrated water is discharged from the upper part of the ozone catalytic oxidation tower; wherein:
the ratio of the total mass of the added ozone to the total mass of organic matters in the active sand filtration concentrated water by chemical oxygen demand is 1-5: 1, the space velocity is 0.5 to 5h-1The contact reaction time of the ozone and the active sand filtration concentrated water is 30-60min, the hydraulic retention time is 60-150min, and the temperature of the active sand filtration concentrated water is controlled at 15-30 ℃.
6. The treatment method according to claim 5, wherein the ozone catalytic oxidation tower is filled with an aluminum-based catalyst, and the volume of the aluminum-based catalyst accounts for 50-90% of the total volume of the ozone catalytic oxidation tower;
in the aluminum-based catalyst, the mass content of aluminum oxide is 24-45%, the mass content of copper oxide is 15-45%, the mass content of manganese oxide is 10-30%, the mass content of nickel oxide is 5-20%, and the balance is at least one of iron oxide, titanium oxide, zinc oxide and cerium oxide; the porosity of the aluminum-based catalyst is 45-75%.
7. The treatment method according to claim 1 or 2, wherein, in the biochemical treatment process, the ratio of the total amount of the wastewater in terms of biochemical oxygen demand: nitrogen source: the phosphorus source is (95-110): (3-8): (0.5-1.3) adding a nutrient source into the secondary oxidation concentrated water, and controlling the dissolved oxygen of the secondary oxidation concentrated water to be 4-6mg/L and the water temperature to be 15-30 ℃.
8. A method for purifying refinery waste water is characterized by comprising the following steps:
treating the refining wastewater by adopting a reverse osmosis membrane and/or a nanofiltration membrane to obtain standard water and concentrated water;
the treatment method according to any one of claims 1 to 7, wherein the concentrated water is treated.
9. A membrane concentrated water treatment device for implementing the treatment method of any one of claims 1 to 8, which is characterized by comprising a concentrated water collecting tank, a flocculation precipitation device, an active sand filter, an ozone catalytic oxidation tower and a biological aerated filter which are connected in sequence, wherein:
the concentrated water collecting tank is used for carrying out primary ozone oxidation on the membrane concentrated water to be treated and is provided with a gas inlet;
the flocculation precipitation equipment is used for carrying out coagulation and precipitation on the primary oxidation concentrated water;
the active sand filter is used for filtering the supernatant by the active sand;
the ozone catalytic oxidation tower is used for carrying out secondary ozone oxidation on the active sand filtration concentrated water, and a gas outlet of the ozone catalytic oxidation tower for discharging the tail gas is connected with a gas inlet of the concentrated water collecting tank;
the biological aerated filter is used for carrying out the biochemical treatment on the secondary oxidation concentrated water.
10. The treatment apparatus of claim 9, wherein the treatment apparatus comprises at least two catalytic ozonation towers connected in series.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111732224A (en) * | 2020-07-03 | 2020-10-02 | 广州市金龙峰环保设备工程股份有限公司 | Physicochemical treatment system for chemical waste liquid pretreatment and use method thereof |
| CN114426351A (en) * | 2020-09-27 | 2022-05-03 | 中国石油化工股份有限公司 | Oil refining wastewater treatment process and device and application |
| CN115196832A (en) * | 2022-07-19 | 2022-10-18 | 郑州中科新兴产业技术研究院 | Ozone oxidation technology for high-concentration wastewater treatment |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1796314A (en) * | 2004-12-24 | 2006-07-05 | 中国科学院生态环境研究中心 | Method for processing urban sewage deeply |
| CN101182084A (en) * | 2007-11-15 | 2008-05-21 | 天津市市政工程设计研究院 | Combined treating method for reclaimed water reuse |
| CN101863589A (en) * | 2010-06-09 | 2010-10-20 | 中国海洋石油总公司 | Method for advanced treatment of wastewater by using combination of catalytic ozonation and internal circulation biological filter |
| CN102303939A (en) * | 2011-08-12 | 2012-01-04 | 华南理工大学 | Front, middle and rear ozone and central aerated biological activated carbon water supply treatment method |
| CN205347102U (en) * | 2015-12-08 | 2016-06-29 | 神华集团有限责任公司 | Degree of depth processing system of direct liquefaction of coal sewage |
| CN106277553A (en) * | 2015-05-27 | 2017-01-04 | 麦王环境技术股份有限公司 | The processing method of the dense water of reverse osmosis (RO) and equipment |
-
2018
- 2018-12-07 CN CN201811496879.8A patent/CN111285491A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1796314A (en) * | 2004-12-24 | 2006-07-05 | 中国科学院生态环境研究中心 | Method for processing urban sewage deeply |
| CN101182084A (en) * | 2007-11-15 | 2008-05-21 | 天津市市政工程设计研究院 | Combined treating method for reclaimed water reuse |
| CN101863589A (en) * | 2010-06-09 | 2010-10-20 | 中国海洋石油总公司 | Method for advanced treatment of wastewater by using combination of catalytic ozonation and internal circulation biological filter |
| CN102303939A (en) * | 2011-08-12 | 2012-01-04 | 华南理工大学 | Front, middle and rear ozone and central aerated biological activated carbon water supply treatment method |
| CN106277553A (en) * | 2015-05-27 | 2017-01-04 | 麦王环境技术股份有限公司 | The processing method of the dense water of reverse osmosis (RO) and equipment |
| CN205347102U (en) * | 2015-12-08 | 2016-06-29 | 神华集团有限责任公司 | Degree of depth processing system of direct liquefaction of coal sewage |
Non-Patent Citations (5)
| Title |
|---|
| 朱晨: "微絮凝砂滤—臭氧催化氧化深度处理石化二级出水中试研究", 《中国优秀博硕士学位论文全文数据库(硕士)工程科技Ⅰ辑》 * |
| 段锋等: "反渗透浓水中难降解有机物的去除技术研究进展", 《工业水处理》 * |
| 沈晓强等: "催化臭氧氧化―生物活性炭吸附组合工艺处理反渗透浓水", 《化工环保》 * |
| 陈丽娜 等: "反渗透浓盐水零排放处理工艺技术", 《经济•管理•综述》 * |
| 龚小芝 等: "石化厂污水反渗透浓水的催化臭氧氧化处理", 《化工环保》 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111732224A (en) * | 2020-07-03 | 2020-10-02 | 广州市金龙峰环保设备工程股份有限公司 | Physicochemical treatment system for chemical waste liquid pretreatment and use method thereof |
| CN114426351A (en) * | 2020-09-27 | 2022-05-03 | 中国石油化工股份有限公司 | Oil refining wastewater treatment process and device and application |
| CN115196832A (en) * | 2022-07-19 | 2022-10-18 | 郑州中科新兴产业技术研究院 | Ozone oxidation technology for high-concentration wastewater treatment |
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Application publication date: 20200616 |