Systematic treatment method for catalytic oxidation and high-efficiency biochemical treatment of high-concentration organic wastewater

Abstract

The application belongs to the technical field of wastewater treatment, and particularly relates to a systematic treatment method for high-concentration organic wastewater by catalytic oxidation and efficient biochemical treatment, which comprises the following steps: filtering and removing the precipitate of the high-concentration organic wastewater to be treated, and adjusting the PH of the pretreated liquid to be acidic; performing catalytic oxidation on the pretreated liquid at 150 DEG C, wherein the effective component in the catalyst is 0.5% of the mass of the pretreated liquid, the effective component in the oxidant is 0.3% of the mass of the pretreated liquid, and the oxidation is continued until the pretreated liquid is neutral to obtain a neutral solution; and performing biochemical treatment on the neutral solution in a biochemical tank. The method of the application combines catalytic oxidation with biochemical treatment, thereby reducing the treatment cost and avoiding secondary pollution.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wastewater treatment, in particular to a systematic treatment method for high-concentration organic wastewater by catalytic oxidation and efficient biochemical treatment. BACKGROUND

[0002] The description of the background of the present application belongs to the related art related to the present application, and is only used to illustrate and facilitate the understanding of the content of the present application, and should not be understood as the applicant's explicit recognition or presumption that the present application is the prior art on the date of the first filing of the application.

[0003] There are a large amount of organic matter with poor biodegradability in organic wastewater. The current common methods for treating such high-concentration wastewater in enterprises include evaporation method, Fenton oxidation method, electro-catalytic oxidation method and ozone catalytic oxidation.

[0004] The evaporation method has very high cost for separating and disposing pollutants through evaporation; the Fenton oxidation method uses hydrogen peroxide as an oxidizing agent to degrade wastewater at normal temperature and pressure, which generates a large amount of iron sludge, increasing the disposal cost of solid waste; the electro-catalytic oxidation method generates intermediate substances with strong oxidation or intermediate reactions other than anode reactions through anode oxidation or anode reactions, which, under the synergistic action of catalysts, makes the treated pollutants oxidize, and finally achieves the purpose of oxidizing and degrading pollutants. The problems existing in the use of electro-catalytic oxidation method are: the wastewater must contain a certain amount of salt, the higher the salt content, the lower the energy consumption under the same current density; when the wastewater hardness is high, the electrode plate is easy to scale, which needs to be acid washed regularly, thus causing secondary pollution; the electrode plate is a consumable with high investment; the ozone oxidation method mainly reacts with organic matter through active hydroxyl radicals to break the unsaturated bond in the chromophoric group, so as to achieve the purpose of decolorization and degradation of organic matter. The disadvantages are high cost of ozone generation, low utilization rate and low COD removal rate.

[0005] As can be seen from the above treatment methods, the electro-catalytic oxidation method and the ozone oxidation method have the problems of high cost and high engineering difficulty, and the evaporation method and the Fenton oxidation method have the risk of secondary pollution although they have mild conditions and low cost.

[0006] Currently, some processes that combine catalytic oxidation with biochemical treatment are used to treat high-concentration organic wastewater. For example, the patent application with the application number 202010955961.3 uses the ammonia evaporation method in the ammonia nitrogen removal process in the catalytic oxidation process, but it needs to detect the ammonia nitrogen concentration in the wastewater all the time, and the wastewater is treated according to the different ammonia nitrogen concentrations, which greatly increases the complexity of operation and the difficulty of control. SUMMARY

[0007] The embodiment of the present application aims to provide a systematic treatment method of high-concentration organic wastewater by catalytic oxidation and high-efficiency biochemical treatment.

[0008] The present application aims to achieve the following technical solutions:

[0009] The embodiment of the present application aims to provide a systematic treatment method of high-concentration organic wastewater by catalytic oxidation and high-efficiency biochemical treatment.

[0010] Further, the catalyst is a honeycomb-type carbon sphere loaded with iron-manganese composite powder; the oxidant is sodium hypochlorite; and the volume percentage of the mesopores in the honeycomb-type carbon sphere in the catalyst is 10-20%.

[0011] Further, the catalytic oxidation is performed by intermittently applying microwaves while using the catalyst and the oxidant, and the ratio of the microwave application time to the interval time is 1-2, and the microwave application time is 5-10 s.

[0012] Further, the biochemical treatment is anoxic treatment, aerobic treatment and aerated biological fluidized bed treatment in sequence.

[0013] Further, the dissolved oxygen in the anoxic tank is not more than 0.2 mg / l, the hydraulic retention time is greater than 15 hours, the facultative anaerobic bacteria degrade organic matter and remove ammonia nitrogen, the dissolved oxygen in the aerobic treatment is controlled to be 3.5-4.5 mg / l, the hydraulic retention time is 8 hours, the organic pollutants are degraded by the aerobic bacteria, and the ammonia is fixed into nitrate and nitrite; the aeration intensity of the aerated biological fluidized bed is 30 m 3 / m 2 ·h.

[0014] Further, the elastic biological filler is used in the anoxic treatment and the aerobic treatment.

[0015] Further, the hollow fiber membrane is used to filter the suspended matter in the aerated biological fluidized bed treatment.

[0016] Further, the hollow fiber membrane is loaded with a flocculating agent and a demulsifier.

[0017] The embodiment of the present application has the following beneficial effects:

[0018] The method of the present application adopts catalytic oxidation combined with biochemical treatment, reduces treatment cost, and avoids secondary pollution. The catalytic oxidation treatment has obvious effect on organic wastewater treatment, does not produce secondary pollution when reducing the same concentration of organic matter, and can improve the biodegradability of wastewater.

[0019] Compared with the catalytic oxidation combined with biochemical treatment in the background art, the present application does not need to monitor the ammonia nitrogen concentration in the wastewater to control the next process, is more practical, and is easier to control. DETAILED DESCRIPTION

[0020] The present application will be further described below in combination with examples.

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, in the following description, different "an embodiment" or "embodiments" do not necessarily refer to the same embodiment. Different embodiments can be replaced or combined, and other embodiments can be obtained by those skilled in the art without creative labor.

[0022] A systematic treatment method of high-concentration organic wastewater by catalytic oxidation and high-efficiency biochemical treatment, comprising the following steps: filtering and removing the precipitate of the high-concentration organic wastewater to be treated, adjusting the pH to be acidic to obtain a pretreated liquid; catalytically oxidizing the pretreated liquid at 150 DEG C, the effective component of the catalyst being 0.5% of the mass of the pretreated liquid, the effective component of the oxidizing agent being 0.3% of the mass of the pretreated liquid, and continuing until the pretreated liquid is neutral to obtain a neutral solution; and biochemically treating the neutral solution in a biochemical tank.

[0023] In some embodiments of the present application, the catalyst is a honeycomb type carbon sphere loaded with iron-manganese composite powder; the oxidizing agent is sodium hypochlorite; and the volume percentage of the mesopores in the honeycomb type carbon sphere in the catalyst is 10-20%.

[0024] In some embodiments of the present application, the catalytic oxidation is performed while the catalyst and the oxidizing agent are used, and microwave is intermittently applied, the ratio of the microwave application time to the interval time being 1-2, and the time of each microwave application being 5-10 s.

[0025] In some embodiments of the present application, the biochemical treatment is anoxic treatment, aerobic treatment and air-lift biological fluidized bed treatment in sequence.

[0026] In some embodiments of the present application, the dissolved oxygen in the anoxic tank is not more than 0.2 mg / l, the hydraulic retention time is greater than 15 hours, facultative anaerobic bacteria degrade organic matter and remove ammonia nitrogen, the aerobic treatment controls the dissolved oxygen at 3.5-4.5 mg / l, the hydraulic retention time is 8 hours, and the organic pollutants are degraded by aerobic bacteria, and the ammonia is fixed as nitrate and nitrite; the aeration intensity of the biological fluidized bed is 30 m 3 / m 2 ·h。

[0027] In some embodiments of the present application, the flexible biological filler is used in the anaerobic treatment and aerobic treatment.

[0028] In some embodiments of the present application, the hollow fiber membrane is used to filter the suspended matter in the biological fluidized bed treatment.

[0029] In some embodiments of the present application, the hollow fiber membrane surface is loaded with flocculants and demulsifiers.

[0030] The embodiments of the present application have the following beneficial effects:

[0031] The method of the present application uses catalytic oxidation combined with biochemical treatment, which reduces the treatment cost and avoids secondary pollution. The catalytic oxidation treatment has obvious effect on organic wastewater treatment, does not produce secondary pollution when reducing the same concentration of organic matter, and can improve the biodegradability of wastewater.

[0032] Compared with the catalytic oxidation combined with biochemical treatment in the background art, the present application does not need to monitor the ammonia nitrogen concentration in the wastewater to control the next process, which is more practical and easier to control.

[0033] Embodiment 1

[0034] This embodiment is for treating the material wastewater produced by a food company, and the initial COD concentration is 83562 mg / L, and the ammonia nitrogen concentration is 6956 mg / L.

[0035] The high concentration organic wastewater to be treated is filtered and precipitate is removed, and then the pH is adjusted to be acidic to obtain a pretreated solution; the pretreated solution is subjected to catalytic oxidation at 150°C, the effective component in the catalyst is 0.5% of the mass of the pretreated solution, and the effective component in the oxidizing agent is 0.3% of the mass of the pretreated solution, until the pretreated solution is neutral to obtain a neutral solution, and the neutral solution is subjected to biochemical treatment in a biochemical tank. The catalyst is a honeycomb carbon sphere loaded with iron-manganese composite powder; the oxidizing agent is sodium hypochlorite; the volume percentage of the pores in the honeycomb carbon sphere in the catalyst is 20%. The biochemical treatment is that the neutral solution is sequentially subjected to anoxic treatment, aerobic treatment and aerated biological fluidized bed treatment. The dissolved oxygen in the anoxic tank is 0.3 mg / l, the hydraulic retention time is 30 hours, the facultative anaerobic bacteria degrade organic matter and remove ammonia nitrogen, the dissolved oxygen in the aerobic treatment is controlled to be 3.6 mg / l, the hydraulic retention time is 12 hours, the organic pollutants are degraded by the aerobic bacteria, and the ammonia is fixed into nitrate and nitrite; the aeration intensity of the aerated biological fluidized bed is 30 m 3 / m 2 ·h. The COD concentration in the treated wastewater is 95 mg / L, and the ammonia nitrogen concentration is 61 mg / L, which meets the discharge standard.

[0036] Example 2

[0037] This example is for treating the material wastewater produced by a pharmaceutical company, the initial COD concentration is 78558 mg / L, and the ammonia nitrogen concentration is 5869 mg / L.

[0038] The high concentration organic wastewater to be treated is filtered and precipitate is removed, and then the pH is adjusted to be acidic to obtain a pretreated solution; the pretreated solution is subjected to catalytic oxidation at 150°C, the effective component in the catalyst is 0.5% of the mass of the pretreated solution, and the effective component in the oxidizing agent is 0.3% of the mass of the pretreated solution, until the pretreated solution is neutral to obtain a neutral solution, and the neutral solution is subjected to biochemical treatment in a biochemical tank. The catalyst is a honeycomb carbon sphere loaded with iron-manganese composite powder; the oxidizing agent is sodium hypochlorite; the volume percentage of the pores in the honeycomb carbon sphere in the catalyst is 15%. In the catalytic oxidation, the catalyst and the oxidizing agent are used, and microwave is intermittently applied, the ratio of the microwave application time to the interval time is 1, and the microwave is applied for 6 s each time. The biochemical treatment is that the neutral solution is sequentially subjected to anoxic treatment, aerobic treatment and aerated biological fluidized bed treatment. The dissolved oxygen in the anoxic tank is 0.2 mg / l, the hydraulic retention time is 20 hours, the facultative anaerobic bacteria degrade organic matter and remove ammonia nitrogen, the dissolved oxygen in the aerobic treatment is controlled to be 4.1 mg / l, the hydraulic retention time is 8 hours, the organic pollutants are degraded by the aerobic bacteria, and the ammonia is fixed into nitrate and nitrite; the aeration intensity of the aerated biological fluidized bed is 30 m 3 / m 2COD concentration in the treated wastewater is 69 mg / L and ammonia nitrogen concentration is 46 mg / L, which meets the discharge standard.

[0039] Compared with Example 1, the above example increases the microwave treatment and strengthens the treatment effect, and the wastewater treatment result is obviously better than that of Example 1.

[0040] Example 3

[0041] In this example, the wastewater from a certain antibiotic production company is treated, and the initial COD concentration is 65410 mg / L and the ammonia nitrogen concentration is 4866 mg / L.

[0042] The high-concentration organic wastewater to be treated is filtered and precipitate is removed, and then the pH is adjusted to be acidic to obtain a pretreated solution; the pretreated solution is subjected to catalytic oxidation at 150°C, the effective component in the catalyst is 0.5% of the mass of the pretreated solution, and the effective component in the oxidizing agent is 0.3% of the mass of the pretreated solution, and the process is continued until the pretreated solution is neutral to obtain a neutral solution, and the neutral solution is subjected to biochemical treatment in a biochemical tank. The catalyst is a honeycomb type carbon sphere loaded with iron-manganese composite powder; the oxidizing agent is sodium hypochlorite; the volume percentage of the pore in the honeycomb type carbon sphere in the catalyst is 15%. In the catalytic oxidation, the catalyst and the oxidizing agent are used at the same time, and microwave is intermittently applied, the ratio of the microwave application time to the interval time is 1, and the time for each microwave application is 6s. The biochemical treatment is that the neutral solution is sequentially subjected to anoxic treatment, aerobic treatment and aerated biological fluidized bed treatment. In the anoxic tank treatment, the dissolved oxygen is 0.2 mg / l, the hydraulic retention time is 16 hours, the facultative anaerobic bacteria degrade organic matter and remove ammonia nitrogen, the dissolved oxygen is controlled to be 4.5 mg / l in the aerobic treatment, the hydraulic retention time is 8 hours, the organic pollutants are degraded by the action of aerobic bacteria, and the ammonia is fixed into nitrate and nitrite; the aeration intensity of the aerated biological fluidized bed is 30 m 3 / m 2 COD concentration in the treated wastewater is 55 mg / L and ammonia nitrogen concentration is 41 mg / L, which meets the discharge standard.

[0043] From the above examples, it can be seen that the scheme of the present application has obvious treatment effect on wastewater with high COD and ammonia nitrogen concentration (Examples 1 and 2) and wastewater with low concentration (Example 3).

[0044] It can be understood that in the present application, the adjustment of pH can use any one or a combination of multiple of hydrochloric acid, sulfuric acid and nitric acid. The carrier of the catalyst can be carbon sphere, diatomite ball, zeolite, ceramic ball, etc.; the active component can also be a compound containing multiple elements of manganese, gold, platinum and ruthenium.

[0045] It should be noted that the above embodiments can be freely combined as needed. The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A systematic treatment method of catalytic oxidation and high-efficiency biochemical treatment of high-concentration organic wastewater, characterized in that, The method comprises the following steps: filtering and removing the precipitate of the high-concentration organic wastewater to be treated, adjusting the pH of the pretreated liquid to be acidic, catalytically oxidizing the pretreated liquid at 150 DEG C, the effective component of the catalyst being 0.5% of the mass of the pretreated liquid, the effective component of the oxidant being 0.3% of the mass of the pretreated liquid, and the oxidation being continued until the pretreated liquid is neutral to obtain a neutral solution, and biochemically treating the neutral solution in a biochemical tank. The catalyst is a honeycomb type carbon sphere loaded with iron-manganese composite powder; the oxidant is sodium hypochlorite; the volume percentage of the holes in the honeycomb type carbon sphere in the catalyst is 10-20%. In the catalytic oxidation, the catalyst and the oxidant are used while intermittently applying microwaves, the ratio of the microwave application time to the interval time is 1-2, and the time of each microwave application is 5-10s. The biochemical treatment is to sequentially perform anoxic treatment, aerobic treatment and air-lifted biological fluidized bed treatment on the neutral solution.

2. The systemized treatment method of high concentrated organic wastewater by catalytic oxidation and efficient biochemical process according to claim 1, characterized in that, The dissolved oxygen in the anoxic tank is not more than 0.2 mg / l, the hydraulic retention time is greater than 15 hours, the facultative anaerobic bacteria degrade the organic matter and remove the ammonia nitrogen, the dissolved oxygen in the aerobic treatment is controlled in 3.5-4.5 mg / l, the hydraulic retention time is 8 hours, the organic pollutants are degraded by the aerobic bacteria, and the ammonia is fixed into nitrate and nitrite; the aeration intensity of the biological fluidized bed is 30 m 3 / m 2 ·h.

3. The systemized treatment method of high concentrated organic wastewater by catalytic oxidation and efficient biochemical process according to claim 2, characterized in that, In the air-lifted biological fluidized bed treatment, hollow fiber membranes are used to filter the suspended matters.

4. The systemized treatment method of high concentrated organic wastewater by catalytic oxidation and efficient biochemical process according to claim 3, characterized in that, The surface of the hollow fiber membranes is loaded with flocculants and demulsifiers.