A method and device system for treating pulping wastewater

Abstract

This invention relates to a method and system for treating pulping wastewater. The method includes: mixing pulping wastewater and papermaking wastewater for coagulation treatment to obtain coagulated water; the coagulated water entering a primary sedimentation tank for primary sedimentation treatment to obtain primary sedimentation water; the primary sedimentation water entering an equalization tank, where it is mixed with effluent from the secondary sedimentation tank of a papermaking wastewater treatment system for equalization treatment to obtain equalized water; the equalized water entering a pre-acidification tank, where it is mixed with effluent from the secondary sedimentation tank of a papermaking wastewater treatment system for pre-acidification treatment to obtain pre-acidified water; and the pre-acidified water entering an anaerobic reactor for anaerobic purification treatment to obtain treated water. The treatment method provided by this invention can reduce the harm of pollutants such as H2O2 and lignin in pulping wastewater to anaerobic bacteria, improve the anaerobic treatment effect, and reduce the COD content of the treated water, thus having application prospects and industrial value.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of sewage treatment, in particular to a pulping wastewater treatment method and a treatment device system thereof. BACKGROUND

[0002] Due to the significant reduction of foreign waste import quota year by year, the domestic waste paper supply is becoming tight, which not only makes small enterprises face difficulties in obtaining high-quality fiber sources, but also promotes the rise of the cost of raw materials of waste paper. In order to solve the problem of raw material shortage, it is urgent to seek alternative raw materials for waste paper. Among them, wood chips are considered to be able to partially replace waste paper as a papermaking raw material and be processed by pulping method. However, pulping method will produce wastewater containing high-concentration COD, wood fiber, lignin and hydrogen peroxide and other pollutants in the production process. These pollutants will have a serious impact on the sewage treatment system and greatly increase the difficulty of sewage treatment.

[0003] In the wastewater discharged by the pulping method, lignin has inertia, strong chemical stability and antioxidant properties, and is insoluble in common organic solvents, and it is basically impossible to remove lignin in the existing pulping wastewater treatment process. Lignin also has strong adsorption, which will be adsorbed on the anaerobic granular sludge when passing through the anaerobic section of the sewage system, isolating anaerobic bacteria from the sewage, inhibiting the activity of anaerobic bacteria, and reducing the operating efficiency of the anaerobic section. In addition, the pulping wastewater contains chemicals such as H2O2, OH - and residues. H2O2 is a peroxide, which is unstable in nature. The unbound oxygen molecule has strong oxidizing power, which can destroy the structure of bacteria when it comes into contact with bacteria, thereby killing the bacteria. Therefore, the pulping wastewater of wood chips has a fatal damage to the anaerobic and aerobic microorganisms of the sewage treatment system.

[0004] For example, CN106277617A discloses a comprehensive treatment process for pulping wastewater in a papermaking process, which mainly includes collection of pulping wastewater, filtration of pulping wastewater, sedimentation treatment, anaerobic treatment, secondary sedimentation treatment and aeration treatment. The waste liquid after aeration treatment is subjected to biological treatment, and the waste liquid after biological treatment is subjected to filtration treatment and disinfection treatment. However, this treatment process still cannot solve the serious impact of H2O2, lignin and other pollutants in wood chip pulping wastewater on the sewage treatment system.

[0005] Therefore, how to reduce the harm of H2O2, lignin and other pollutants in pulping wastewater and improve the anaerobic treatment effect is a technical problem to be solved in the present field. SUMMARY

[0006] In view of the above problems, the present application aims to provide a pulp wastewater treatment method and a treatment device system thereof, which can reduce the harm of H2O2, lignin and other pollutants in the pulp wastewater to anaerobic bacteria, improve the anaerobic treatment effect, reduce the COD content of the treated water, is environmentally friendly, and has application prospect and industrial value.

[0007] To achieve the object of the present application, the following technical solutions are adopted:

[0008] In a first aspect, the present application provides a pulp wastewater treatment method, which comprises the following steps:

[0009] (1) mixing the pulp wastewater and the papermaking wastewater for coagulation treatment to obtain coagulated water;

[0010] (2) the coagulated water obtained in step (1) is subjected to primary sedimentation treatment in a primary sedimentation tank to obtain primary sedimentation water;

[0011] (3) the primary sedimentation water obtained in step (2) is subjected to adjustment treatment in a conditioning tank by mixing with the effluent from the secondary sedimentation tank of the papermaking wastewater treatment system to obtain adjusted water;

[0012] (4) the adjusted water obtained in step (3) is subjected to pre-acidification treatment in a pre-acidification tank by mixing with the effluent from the secondary sedimentation tank of the papermaking wastewater treatment system to obtain pre-acidification water;

[0013] (5) the pre-acidification water obtained in step (4) is subjected to anaerobic purification treatment in an anaerobic reactor to obtain treated water.

[0014] The papermaking wastewater used in the present application contains various free cations (such as Ca 2+ , Fe 2+ , Fe 3+ , etc.). On the one hand, the pulp wastewater and the papermaking wastewater are mixed in the present application, which can consume the residual H2O2 in the pulp wastewater by using the cations in the papermaking wastewater, thereby avoiding the sterilization of the H2O2 to the microbial treatment system of the wastewater treatment system; on the other hand, the pulp wastewater contains a large amount of lignin, and the present application utilizes the adsorption properties and affinity of the lignin to metal elements, and the metal cations and metal compounds in the papermaking wastewater are adsorbed and precipitated by the lignin, thereby controlling the precipitation of the lignin in the pulp wastewater from the water body, thereby avoiding the influence of the lignin on the anaerobic microorganisms; on the other hand, the present application utilizes the effluent from the secondary sedimentation tank of the papermaking wastewater treatment system, which contains a large amount of Ca 2+It can further remove H2O2 and lignin in the equalization tank and pre-acidification tank. In addition, the papermaking wastewater and its secondary sedimentation tank effluent have low COD content, which can dilute the COD concentration entering the anaerobic reactor, reduce the instantaneous shock load on microorganisms during anaerobic purification, and improve the anaerobic treatment effect.

[0015] In this invention, the operation methods of the pre-acidification treatment and anaerobic purification treatment are conventional operations in the field. The pre-acidification treatment involves using hydrolytic and acidifying bacteria in a pre-acidification tank to perform hydrolysis and acidification. During hydrolysis, polymers such as polysaccharides, polypeptides, and fats are broken down into their monomers such as sugars, amino acids, and fatty acids. During acidification, these monomers are converted into organic acids, alcohols, aldehydes, hydrogen, and carbon dioxide. The anaerobic purification treatment involves using anaerobic microorganisms in an anaerobic reactor to decompose and remove chemical or biological impurities.

[0016] Preferably, the H2O2 content in the pulping wastewater is 10-30 mg / L, for example, it can be 10 mg / L, 12 mg / L, 15 mg / L, 18 mg / L, 20 mg / L, 22 mg / L, 25 mg / L, 28 mg / L or 30 mg / L, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0017] Preferably, the lignin content in the pulping wastewater is 1500-2500 mg / L, for example, it can be 1500 mg / L, 1600 mg / L, 1700 mg / L, 1800 mg / L, 1900 mg / L, 2000 mg / L, 2100 mg / L, 2200 mg / L, 2300 mg / L, 2400 mg / L or 2500 mg / L, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0018] Preferably, the COD concentration in the pulping wastewater is 15,000-20,000 mg / L, for example, it can be 15,000 mg / L, 15,500 mg / L, 16,000 mg / L, 16,500 mg / L, 17,000 mg / L, 17,500 mg / L, 18,000 mg / L, 18,500 mg / L, 19,000 mg / L, 19,500 mg / L or 20,000 mg / L, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0019] Preferably, the pH value of the pulping wastewater is 6-12, for example, it can be 6, 7, 8, 9, 10, 11 or 12, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0020] Preferably, the Fe in the papermaking wastewater 3+The content is 2-4 mg / L, for example, it can be 2 mg / L, 2.2 mg / L, 2.5 mg / L, 2.8 mg / L, 3 mg / L, 3.2 mg / L, 3.5 mg / L, 3.8 mg / L or 4 mg / L, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0021] Preferably, the Ca in the papermaking wastewater 2+ The content is 300-500 mg / L, for example, it can be 300 mg / L, 320 mg / L, 350 mg / L, 380 mg / L, 400 mg / L, 420 mg / L, 450 mg / L, 480 mg / L or 500 mg / L, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0022] Preferably, the COD content of the papermaking wastewater is 7000-9000 mg / L, for example, it can be 7000 mg / L, 7200 mg / L, 7500 mg / L, 7800 mg / L, 8000 mg / L, 8200 mg / L, 8500 mg / L, 8800 mg / L or 9000 mg / L, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0023] Preferably, the Ca in the effluent from the secondary sedimentation tank 2+ The content is 300-500 mg / L, for example, it can be 300 mg / L, 320 mg / L, 350 mg / L, 380 mg / L, 400 mg / L, 420 mg / L, 450 mg / L, 480 mg / L or 500 mg / L, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0024] Preferably, the COD content of the effluent from the secondary sedimentation tank is ≤250mg / L, for example, it can be 250mg / L, 240mg / L, 230mg / L, 220mg / L, 210mg / L or 200mg / L, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0025] Preferably, the mass ratio of pulping wastewater to papermaking wastewater in the coagulation treatment in step (1) is 1:(1.5-2.5), for example, it can be 1:1.5, 1:1.6, 1:1.7, 1:1.8, 1:1.9, 1:2, 1:2.1, 1:2.2, 1:2.3, 1:2.4 or 1:2.5, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0026] In this invention, it is preferable to control the mass ratio of pulping wastewater to papermaking wastewater in the coagulation treatment. On the one hand, this can effectively remove residual H2O2 from the pulping wastewater and promote lignin precipitation. On the other hand, it avoids excessive papermaking wastewater addition causing an overload of the anaerobic system, excessive metal elements, and reduced treatment efficiency.

[0027] Preferably, the H2O2 content in the coagulated water is 0-5 mg / L, for example, it can be 0 mg / L, 1 mg / L, 2 mg / L, 3 mg / L, 4 mg / L or 5 mg / L, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0028] Preferably, the lignin content in the coagulated water is 0-500 mg / L, for example, it can be 0 mg / L, 50 mg / L, 100 mg / L, 150 mg / L, 200 mg / L, 250 mg / L, 300 mg / L, 350 mg / L, 400 mg / L, 450 mg / L or 500 mg / L, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0029] Preferably, the COD content of the coagulated water is 6000-10000 mg / L, for example, it can be 6000 mg / L, 6500 mg / L, 7000 mg / L, 7500 mg / L, 8000 mg / L, 8500 mg / L, 9000 mg / L, 9500 mg / L or 10000 mg / L, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0030] Preferably, sludge is also generated at the bottom of the primary sedimentation tank in step (2).

[0031] Preferably, the sludge at the bottom of the primary sedimentation tank is discharged into the sludge treatment unit via a sludge discharge pipeline.

[0032] Preferably, the mass ratio of the water after primary sedimentation to the effluent from the secondary sedimentation tank of the papermaking wastewater treatment system in step (3) is 1:(1-2), for example, it can be 1:1, 1:1.2, 1:1.4, 1:1.6, 1:1.8 or 1:2, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0033] In this invention, it is preferable to control the mass ratio of the water after primary sedimentation to the effluent from the secondary sedimentation tank. This can further remove residual hydrogen peroxide, further precipitate lignin, and reduce the COD concentration of the effluent, while avoiding excessive metal elements from affecting the anaerobic removal rate.

[0034] Preferably, the lignin content of the adjusted water is 0-100 mg / L, for example, it can be 0 mg / L, 10 mg / L, 20 mg / L, 30 mg / L, 40 mg / L, 50 mg / L, 60 mg / L, 70 mg / L, 80 mg / L, 90 mg / L or 100 mg / L, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0035] Preferably, the COD content of the adjusted water is 3000-5000 mg / L, for example, it can be 3000 mg / L, 3500 mg / L, 4000 mg / L, 4500 mg / L or 5000 mg / L, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0036] Preferably, the H2O2 content in the adjusted water is 0-2 mg / L, for example, it can be 0 mg / L, 0.2 mg / L, 0.4 mg / L, 0.6 mg / L, 0.8 mg / L, 1 mg / L, 1.2 mg / L, 1.4 mg / L, 1.6 mg / L, 1.8 mg / L or 2 mg / L, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0037] Preferably, sludge is also generated at the bottom of the equalization tank.

[0038] Preferably, the sludge at the bottom of the equalization tank is discharged into the sludge treatment unit via a sludge discharge pipeline.

[0039] In this invention, due to the precipitation of lignin and other reasons, sediment is formed at the bottom of the non-sedimentation tank, i.e., the equalization tank. In order to avoid long-term impact on the effective operating space of the tank and to avoid affecting the adjustment of the treatment system, multiple sludge discharge pipelines are arranged at various corners of the equalization tank. Finally, the sludge is transported to the sludge treatment unit by a sludge pump. In the sludge treatment unit, the sludge is treated by a filtration device such as a plate and frame filter press, and then sent to the power plant for incineration.

[0040] Preferably, the mass ratio of the adjusted water to the effluent from the secondary sedimentation tank of the papermaking wastewater treatment system in the pre-acidification treatment in step (4) is 1:(1-2), for example, it can be 1:1, 1:1.2, 1:1.4, 1:1.6, 1:1.8 or 1:2, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0041] In this invention, the mass ratio of the adjusted water to the secondary sedimentation tank effluent is preferably controlled to further fully adsorb residual lignin, reduce the COD concentration entering the anaerobic reactor, reduce the shock load on anaerobic bacteria, and at the same time avoid excessive addition of secondary sedimentation tank effluent, which would cause the calcium ions and sulfate ions contained therein to have an adverse effect on the anaerobic system. In addition, the secondary sedimentation tank effluent is the wastewater after biological treatment and has low biodegradability.

[0042] Preferably, the lignin content of the water after pre-acidification is 0-30 mg / L, for example, it can be 0 mg / L, 5 mg / L, 10 mg / L, 15 mg / L, 20 mg / L, 25 mg / L or 30 mg / L, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0043] Preferably, the COD content of the pre-acidified water is 2000-3000 mg / L, for example, it can be 2000 mg / L, 2100 mg / L, 2200 mg / L, 2300 mg / L, 2400 mg / L, 2500 mg / L, 2600 mg / L, 2700 mg / L, 2800 mg / L, 2900 mg / L or 3000 mg / L, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0044] Preferably, the pH value of the pre-acidified water is 6-7, for example, it can be 6, 6.2, 6.4, 6.6, 6.8 or 7, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0045] Preferably, the wastewater in the pre-acidification treatment is recycled back to the pre-acidification tank.

[0046] In this invention, by controlling the wastewater in the pre-acidification treatment to be circulated back, the pH value of the pre-acidification treatment can be sampled and monitored in the return pipeline.

[0047] Preferably, sludge is also generated at the bottom of the pre-acidification tank.

[0048] Preferably, the sludge at the bottom of the pre-acidification tank is discharged into the sludge treatment unit via a sludge discharge pipeline.

[0049] In this invention, due to the precipitation of lignin and other reasons, sediment is formed at the bottom of the non-sedimentation tank, i.e., the pre-acidification tank. In order to avoid long-term impact on the effective operating space of the tank and to avoid affecting the adjustment of the treatment system, multiple sludge discharge pipelines are arranged in various corners of the pre-acidification tank. Finally, the sludge is transported to the sludge treatment unit by a sludge discharge pump. In the sludge treatment unit, the sludge is treated by a filtration device such as a plate and frame filter press, and then sent to the power plant for incineration.

[0050] Preferably, the upper wastewater in the anaerobic purification process described in step (5) is recycled back to the inlet of the anaerobic reactor.

[0051] Preferably, the percentage of the circulating return water to the inlet water of the anaerobic reactor is 30-50%, for example, it can be 30%, 32%, 35%, 38%, 40%, 42%, 45%, 48% or 50%, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0052] As a preferred embodiment of the first aspect of the present invention, the processing method includes the following steps:

[0053] (1) Pulping wastewater and papermaking wastewater are mixed at a mass ratio of 1:(1.5-2.5) and subjected to coagulation treatment. The pulping wastewater contains 10-30 mg / L of H2O2, 1500-2500 mg / L of lignin, 15000-20000 mg / L of COD, and has a pH value of 6-12. The papermaking wastewater contains Fe... 3+ The content is 2-4 mg / L, Ca 2+ The content is 300-500 mg / L, the COD content is 7000-9000 mg / L, and the coagulated water is obtained. The content of H2O2 in the coagulated water is 0-5 mg / L, the content of lignin is 0-500 mg / L, and the COD content is 6000-10000 mg / L.

[0054] (2) The coagulated water obtained in step (1) enters the primary sedimentation tank for primary sedimentation treatment to obtain the primary sedimentation water. Sludge is also generated at the bottom of the primary sedimentation tank. The sludge at the bottom of the primary sedimentation tank is discharged into the sludge treatment unit through the sludge discharge pipeline.

[0055] (3) The initial sedimentation water obtained in step (2) enters the equalization tank. In the equalization tank, the initial sedimentation water is mixed with the effluent from the secondary sedimentation tank of the papermaking wastewater treatment system for equalization treatment. The mass ratio of the initial sedimentation water to the effluent from the secondary sedimentation tank is 1:(1-2). The Ca of the effluent from the secondary sedimentation tank... 2+ The content is 300-500 mg / L, the COD content is ≤250 mg / L, and the lignin content of the regulated water is 0-100 mg / L, the COD content is 3000-5000 mg / L, and the H2O2 content is 0-2 mg / L. Sludge is also generated at the bottom of the regulating tank, and the sludge at the bottom of the regulating tank is discharged into the sludge treatment unit through the sludge discharge pipeline.

[0056] (4) The adjusted water obtained in step (3) enters the pre-acidification tank. In the pre-acidification tank, the adjusted water is mixed with the effluent from the secondary sedimentation tank of the papermaking wastewater treatment system for pre-acidification treatment. The mass ratio of the adjusted water to the effluent from the secondary sedimentation tank is 1:(1-2) to obtain pre-acidified water. The lignin content of the pre-acidified water is 0-30 mg / L, the COD content is 2000-3000 mg / L, and the pH value is 6-7. The wastewater in the pre-acidification treatment is recycled back to the pre-acidification tank. Sludge is also generated at the bottom of the pre-acidification tank. The sludge at the bottom of the pre-acidification tank is discharged into the sludge treatment unit through the sludge discharge pipeline.

[0057] (5) The pre-acidified water obtained in step (4) enters the anaerobic reactor for anaerobic purification treatment. The upper wastewater in the anaerobic purification treatment is recycled back to the inlet of the anaerobic reactor. The amount of recycled water accounts for 30-50% of the inlet water of the anaerobic reactor, and the treated water is obtained.

[0058] In a second aspect, the present invention provides a treatment device system for pulping wastewater, the treatment device system being used for the pulping wastewater treatment method as described in the first aspect of the present invention;

[0059] The treatment system includes a coagulation tank, a primary sedimentation tank, an equalization tank, a pre-acidification tank, and an anaerobic reactor connected sequentially along the wastewater flow direction. The inlet of the coagulation tank is connected to the pulping wastewater pipeline and the papermaking wastewater pipeline, respectively. The inlet of the equalization tank is connected to the effluent pipeline of the primary sedimentation tank and the effluent pipeline of the secondary sedimentation tank of the papermaking wastewater treatment system, respectively. The inlet of the pre-acidification tank is connected to the effluent pipeline of the equalization tank and the effluent pipeline of the secondary sedimentation tank of the papermaking wastewater treatment system, respectively.

[0060] The treatment device system provided by this invention is connected to the pulping wastewater pipeline and the papermaking wastewater pipeline through the inlet of the coagulation tank, the inlet of the equalization tank is connected to the effluent pipeline of the primary sedimentation tank and the effluent pipeline of the secondary sedimentation tank of the papermaking wastewater treatment system, and the inlet of the pre-acidification tank is connected to the effluent pipeline of the equalization tank and the effluent pipeline of the secondary sedimentation tank of the papermaking wastewater treatment system. It can use the papermaking wastewater and the effluent of the secondary sedimentation tank of the papermaking wastewater treatment system to treat H2O2 and lignin in the pulping wastewater, reduce the COD concentration at the inlet of the anaerobic reactor, and improve the anaerobic removal rate.

[0061] Preferably, the bottom sludge outlet of the primary sedimentation tank is connected to the sludge treatment unit via a sludge discharge pipeline.

[0062] Preferably, the bottom sludge outlet of the equalization tank is connected to the sludge treatment unit via a sludge discharge pipeline.

[0063] Preferably, the bottom sludge outlet of the pre-acidification tank is connected to the sludge treatment unit via a sludge discharge pipeline.

[0064] Preferably, the outlet of the pre-acidification tank is connected to the inlet of the pre-acidification tank via a first return pipeline.

[0065] Preferably, the outlet of the anaerobic reactor is connected to the inlet of the anaerobic reactor via a second reflux pipeline.

[0066] Preferably, the outlet of the anaerobic reactor is also connected to a treated water outlet pipeline.

[0067] Preferably, the bottom inlet of the anaerobic reactor is connected to the anaerobic sludge replenishment pipeline.

[0068] Compared with the prior art, the present invention has the following beneficial effects:

[0069] (1) The treatment method provided by this invention mixes pulping wastewater and papermaking wastewater. It utilizes the cations in the papermaking wastewater to consume the residual H2O2 in the pulping wastewater, and leverages the adsorption characteristics and affinity of lignin for metal elements to adsorb and precipitate the metal elements in the papermaking wastewater. This causes the lignin to precipitate from the water, thus avoiding the influence of H2O2 and lignin on anaerobic microorganisms and improving the anaerobic removal rate. Using the treatment method provided by this invention, the anaerobic removal rate can reach over 50%, and under optimal conditions, it can reach over 72%.

[0070] (2) The treatment method provided by the present invention utilizes the fact that the effluent from the secondary sedimentation tank of the papermaking wastewater treatment system contains a large amount of Ca. 2+ It can further remove H2O2 and lignin in the equalization tank and pre-acidification tank, and further improve the anaerobic removal rate.

[0071] (3) The treatment method provided by the present invention utilizes the low COD content of papermaking wastewater and its secondary sedimentation tank effluent to dilute the COD concentration entering the anaerobic reactor, reduce the instantaneous shock load on microorganisms during anaerobic purification treatment, and improve the anaerobic treatment effect.

[0072] (4) The processing device system provided by the present invention has a simple structure, low investment cost, and has application prospects and industrial value. Attached Figure Description

[0073] Figure 1 This is a schematic diagram of the processing device system described in Embodiment 1 of the present invention;

[0074] Among them, 1-coagulation tank; 2-primary sedimentation tank; 3-equalization tank; 4-pre-acidification tank; 5-anaerobic reactor; 6-pulping wastewater pipeline; 7-papermaking wastewater pipeline; 8-secondary sedimentation tank effluent pipeline of papermaking wastewater treatment system; 9-sludge discharge pipeline; 10-sludge treatment unit; 11-first return pipeline; 12-second return pipeline; 13-treated water effluent pipeline; 14-anaerobic sludge replenishment pipeline; 15-electric valve; 16-flow meter; 17-pump; 18-one-way pump. Detailed Implementation

[0075] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0076] Example 1

[0077] This embodiment provides a method for treating pulping wastewater, the method comprising the following steps:

[0078] (1) Pulping wastewater and papermaking wastewater were mixed at a mass ratio of 1:2 for coagulation treatment. The pulping wastewater contained 20 mg / L of H2O2, 2100 mg / L of lignin, 16000 mg / L of COD, and had a pH of 9. The papermaking wastewater contained Fe... 3+ The content is 3 mg / L, Ca 2+ The content is 450 mg / L, the COD content is 8000 mg / L, and the coagulated water is obtained. The content of H2O2 in the coagulated water is 3 mg / L, the content of lignin is 400 mg / L, and the COD content is 9000 mg / L.

[0079] (2) The coagulated water obtained in step (1) overflows into the primary sedimentation tank for primary sedimentation treatment to obtain the primary sedimentation water. Sludge is also generated at the bottom of the primary sedimentation tank. The sludge at the bottom of the primary sedimentation tank is discharged into the sludge treatment unit through the sludge discharge pipeline.

[0080] (3) The primary sedimentation water obtained in step (2) overflows into the equalization tank. In the equalization tank, the primary sedimentation water is mixed with the effluent from the secondary sedimentation tank of the papermaking wastewater treatment system for equalization treatment. The mass ratio of the primary sedimentation water to the effluent from the secondary sedimentation tank is 1:1.5. The Ca of the effluent from the secondary sedimentation tank... 2+ The content is 400 mg / L, the COD content is 250 mg / L, and the lignin content of the regulated water is 60 mg / L, the COD content is 4400 mg / L, and the H2O2 content is 0 mg / L. Sludge is also generated at the bottom of the regulating tank, and the sludge at the bottom of the regulating tank is discharged into the sludge treatment unit through the sludge discharge pipeline.

[0081] (4) The adjusted water obtained in step (3) enters the pre-acidification tank. In the pre-acidification tank, the adjusted water is mixed with the effluent from the secondary sedimentation tank of the papermaking wastewater treatment system for pre-acidification treatment. The mass ratio of the adjusted water to the effluent from the secondary sedimentation tank is 1:1.5 to obtain pre-acidified water. The lignin content of the pre-acidified water is 20 mg / L, the COD content is 2500 mg / L, and the pH value is 6.31. The wastewater in the pre-acidification treatment is recycled back to the pre-acidification tank. Sludge is also generated at the bottom of the pre-acidification tank. The sludge at the bottom of the pre-acidification tank is discharged into the sludge treatment unit through the sludge discharge pipeline.

[0082] (5) The pre-acidified water obtained in step (4) enters the anaerobic reactor for anaerobic purification treatment. The upper wastewater in the anaerobic purification treatment is recycled back to the inlet of the anaerobic reactor. The recycled water accounts for 40% of the inlet water of the anaerobic reactor, and the treated water is obtained.

[0083] This embodiment also provides a processing apparatus system used in the above-described processing method, such as... Figure 1 As shown, the treatment system includes a coagulation tank 1, a primary sedimentation tank 2, an equalization tank 3, a pre-acidification tank 4, and an anaerobic reactor 5 connected sequentially along the wastewater flow direction. The inlet of the coagulation tank 1 is connected to the pulping wastewater pipeline 6 and the papermaking wastewater pipeline 7, respectively. The pulping wastewater pipeline 6 is equipped with an electric valve 15 and a flow meter 16. The inlet of the equalization tank 3 is connected to the effluent pipeline of the primary sedimentation tank 2 and the effluent pipeline of the secondary sedimentation tank of the papermaking wastewater treatment system 8, respectively. The inlet of the pre-acidification tank 4 is connected to the effluent pipeline of the equalization tank 3 and the effluent pipeline of the secondary sedimentation tank of the papermaking wastewater treatment system 8, respectively. The bottom sludge outlet of the primary sedimentation tank 2 is connected to the sludge treatment unit 10 via a sludge discharge pipeline 9, and the bottom sludge outlet of the equalization tank 3 is connected to the sludge treatment unit 10 via a sludge discharge pipeline 9. Unit 10 is connected. The bottom sludge outlet of the pre-acidification tank 4 is connected to the sludge treatment unit 10 via the sludge discharge pipeline 9. The outlet of the pre-acidification tank 4 is connected to the inlet of the pre-acidification tank 4 via the first return pipeline 11. A pH monitoring device (not shown in the figure) is installed on the first return pipeline 11 for sampling and monitoring the pH value in the pre-acidification tank 4. The outlet of the anaerobic reactor 5 is connected to the inlet of the anaerobic reactor 5 via the second return pipeline 12. The outlet pipeline of the pre-acidification tank 4 is also connected to the anaerobic reactor 5. A flow meter 16 is installed on the outlet pipeline of the pre-acidification tank 4. The outlet of the anaerobic reactor 5 is also connected to the treated water outlet pipeline 13. The bottom inlet of the anaerobic reactor 5 is connected to the anaerobic sludge replenishment pipeline 14. In the treatment device system provided in this embodiment, the pipeline is powered by a pump 17 or a one-way pump 18.

[0084] Example 2

[0085] This embodiment provides a method for treating pulping wastewater, the method comprising the following steps:

[0086] (1) Pulping wastewater and papermaking wastewater were mixed at a mass ratio of 1:1.5 and subjected to coagulation treatment. The pulping wastewater contained 10 mg / L of H2O2, 1500 mg / L of lignin, 15000 mg / L of COD, and had a pH of 12. The papermaking wastewater contained Fe... 3+ The content is 2 mg / L, Ca 2+ The content is 300 mg / L, the COD content is 7000 mg / L, and the coagulated water is obtained. The content of H2O2 in the coagulated water is 5 mg / L, the content of lignin is 460 mg / L, and the COD content is 10000 mg / L.

[0087] (2) The coagulated water obtained in step (1) overflows into the primary sedimentation tank for primary sedimentation treatment to obtain the primary sedimentation water. Sludge is also generated at the bottom of the primary sedimentation tank. The sludge at the bottom of the primary sedimentation tank is discharged into the sludge treatment unit through the sludge discharge pipeline.

[0088] (3) The primary sedimentation water obtained in step (2) overflows into the equalization tank. In the equalization tank, the primary sedimentation water is mixed with the effluent from the secondary sedimentation tank of the papermaking wastewater treatment system for equalization treatment. The mass ratio of the primary sedimentation water to the effluent from the secondary sedimentation tank is 1:1. The Ca content of the effluent from the secondary sedimentation tank is... 2+ The content is 300 mg / L, the COD content is 200 mg / L, and the adjusted water has a lignin content of 90 mg / L, a COD content of 5000 mg / L, and an H2O2 content of 2 mg / L. Sludge is also generated at the bottom of the equalization tank, and the sludge at the bottom of the equalization tank is discharged into the sludge treatment unit through the sludge discharge pipeline.

[0089] (4) The adjusted water obtained in step (3) enters the pre-acidification tank. In the pre-acidification tank, the adjusted water is mixed with the effluent from the secondary sedimentation tank of the papermaking wastewater treatment system for pre-acidification treatment. The mass ratio of the adjusted water to the effluent from the secondary sedimentation tank is 1:1 to obtain pre-acidified water. The lignin content of the pre-acidified water is 50 mg / L, the COD content is 3000 mg / L, and the pH value is 6.12. The wastewater in the pre-acidification treatment is recycled back to the pre-acidification tank. Sludge is also generated at the bottom of the pre-acidification tank. The sludge at the bottom of the pre-acidification tank is discharged into the sludge treatment unit through the sludge discharge pipeline.

[0090] (5) The pre-acidified water obtained in step (4) enters the anaerobic reactor for anaerobic purification treatment. The upper wastewater in the anaerobic purification treatment is recycled back to the inlet of the anaerobic reactor. The recycled water accounts for 30% of the inlet water of the anaerobic reactor, and the treated water is obtained.

[0091] This embodiment also provides a processing device system using the above processing method, which is the same as that in Embodiment 1.

[0092] Example 3

[0093] This embodiment provides a method for treating pulping wastewater, the method comprising the following steps:

[0094] (1) Pulping wastewater and papermaking wastewater were mixed at a mass ratio of 1:2.5 and subjected to coagulation treatment. The pulping wastewater contained 30 mg / L of H2O2, 2500 mg / L of lignin, 20000 mg / L of COD, and had a pH of 6. The papermaking wastewater contained Fe... 3+ The content is 4 mg / L, Ca 2+ The content is 500 mg / L, the COD content is 9000 mg / L, and the coagulated water is obtained. The content of H2O2 in the coagulated water is 2 mg / L, the content of lignin is 300 mg / L, and the COD content is 8000 mg / L.

[0095] (2) The coagulated water obtained in step (1) overflows into the primary sedimentation tank for primary sedimentation treatment to obtain the primary sedimentation water. Sludge is also generated at the bottom of the primary sedimentation tank. The sludge at the bottom of the primary sedimentation tank is discharged into the sludge treatment unit through the sludge discharge pipeline.

[0096] (3) The primary sedimentation water obtained in step (2) overflows into the equalization tank. In the equalization tank, the primary sedimentation water is mixed with the effluent from the secondary sedimentation tank of the papermaking wastewater treatment system for equalization treatment. The mass ratio of the primary sedimentation water to the effluent from the secondary sedimentation tank is 1:2. The Ca of the effluent from the secondary sedimentation tank is... 2+ The content is 500 mg / L, the COD content is 210 mg / L, and the lignin content of the regulated water is 30 mg / L, the COD content is 4000 mg / L, and the H2O2 content is 0 mg / L. Sludge is also generated at the bottom of the regulating tank, and the sludge at the bottom of the regulating tank is discharged into the sludge treatment unit through the sludge discharge pipeline.

[0097] (4) The adjusted water obtained in step (3) enters the pre-acidification tank. In the pre-acidification tank, the adjusted water is mixed with the effluent from the secondary sedimentation tank of the papermaking wastewater treatment system for pre-acidification treatment. The mass ratio of the adjusted water to the effluent from the secondary sedimentation tank is 1:2 to obtain pre-acidified water. The lignin content of the pre-acidified water is 5 mg / L, the COD content is 2000 mg / L, and the pH value is 6.85. The wastewater in the pre-acidification treatment is recycled back to the pre-acidification tank. Sludge is also generated at the bottom of the pre-acidification tank. The sludge at the bottom of the pre-acidification tank is discharged into the sludge treatment unit through the sludge discharge pipeline.

[0098] (5) The pre-acidified water obtained in step (4) enters the anaerobic reactor for anaerobic purification treatment. The upper wastewater in the anaerobic purification treatment is recycled back to the inlet of the anaerobic reactor. The recycled water accounts for 45% of the inlet water of the anaerobic reactor, and the treated water is obtained.

[0099] This embodiment also provides a processing device system using the above processing method, which is the same as that in Embodiment 1.

[0100] Example 4

[0101] This embodiment provides a method for treating pulping wastewater, which differs from Embodiment 1 only in that the mass ratio of pulping wastewater to papermaking wastewater is 1:1.

[0102] Example 5

[0103] This embodiment provides a method for treating pulping wastewater, which differs from Embodiment 1 only in that the mass ratio of pulping wastewater to papermaking wastewater is 1:3.

[0104] Example 6

[0105] This embodiment provides a method for treating pulping wastewater. The only difference from Embodiment 1 is that the mass ratio of the water after primary sedimentation to the effluent from the secondary sedimentation tank is 1:0.5.

[0106] Example 7

[0107] This embodiment provides a method for treating pulping wastewater. The only difference from Embodiment 1 is that the mass ratio of the water after primary sedimentation to the effluent from the secondary sedimentation tank is 1:3.

[0108] Example 8

[0109] This embodiment provides a method for treating pulping wastewater. The only difference from Embodiment 1 is that the mass ratio of the adjusted water to the effluent from the secondary sedimentation tank is 1:0.5.

[0110] Example 9

[0111] This embodiment provides a method for treating pulping wastewater. The only difference from Embodiment 1 is that the mass ratio of the adjusted water to the effluent from the secondary sedimentation tank is 1:3.

[0112] Comparative Example 1

[0113] This comparative example provides a method for treating pulping wastewater, which differs from Example 1 only in that papermaking wastewater is not added in the coagulation treatment described in step (1).

[0114] This comparative example also provides a treatment device system for the above-mentioned treatment method, the only difference from Example 1 being that the inlet of the coagulation tank is not connected to the papermaking wastewater pipeline.

[0115] Comparative Example 2

[0116] This comparative example provides a method for treating pulping wastewater. The only difference between this method and Example 1 is that the secondary sedimentation tank effluent of the papermaking wastewater treatment system is not added in the adjustment process described in step (3).

[0117] This embodiment also provides a treatment device system for the above-mentioned treatment method. The only difference from Embodiment 1 is that the inlet of the equalization tank is not connected to the effluent pipeline of the secondary sedimentation tank of the papermaking wastewater treatment system.

[0118] Comparative Example 3

[0119] This comparative example provides a method for treating pulping wastewater. The only difference between this method and Example 1 is that the effluent from the secondary sedimentation tank of the papermaking wastewater treatment system is not added in the pre-acidification treatment described in step (4).

[0120] This comparative example also provides a treatment device system for the above-mentioned treatment method, the only difference from Example 1 is that the inlet of the pre-acidification tank is not connected to the effluent pipeline of the secondary sedimentation tank of the papermaking wastewater treatment system.

[0121] Comparative Example 4

[0122] This comparative example provides a method for treating pulping wastewater. The only difference from Example 1 is that papermaking wastewater is not added in the coagulation treatment in step (1), the secondary sedimentation tank effluent of the papermaking wastewater treatment system is not added in the conditioning treatment in step (3), and the secondary sedimentation tank effluent of the papermaking wastewater treatment system is not added in the pre-acidification treatment in step (4).

[0123] This comparative example also provides a treatment device system for the above-mentioned treatment method. The only difference from Example 1 is that the inlet of the coagulation tank is not connected to the papermaking wastewater pipeline, the inlet of the equalization tank is not connected to the effluent pipeline of the secondary sedimentation tank of the papermaking wastewater treatment system, and the inlet of the pre-acidification tank is not connected to the effluent pipeline of the secondary sedimentation tank of the papermaking wastewater treatment system.

[0124] The H2O2 content in pulping wastewater and pre-acidified water in Examples 1-9 and Comparative Examples 1-3 was detected using a test strip method, and the results are shown in Table 1.

[0125] The lignin content in pulping wastewater and pre-acidified water in Examples 1-9 and Comparative Examples 1-3 was detected by acid-base hydrolysis method, and the results are shown in Table 1.

[0126] The anaerobic removal rate of anaerobic purification treatment in Examples 1-9 and Comparative Examples 1-3 was detected by rapid spectrophotometry, and the results are shown in Table 1.

[0127] Table 1

[0128]

[0129]

[0130] The following points can be observed from the data in Table 1:

[0131] (1) As can be seen from the data of Examples 1-9, the treatment method provided by the present invention can achieve an anaerobic removal rate of more than 50%, and under better conditions, it can achieve more than 72%.

[0132] (2) A comprehensive comparison of the data from Examples 1 and 4-5 shows that the only difference between Examples 4-5 and Example 1 is that the mass ratio of pulping wastewater to papermaking wastewater is not within the preferred range of this invention. The anaerobic removal rate in Example 1 is significantly higher than that in Examples 4-5. Thus, this invention, by optimally controlling the mass ratio of pulping wastewater to papermaking wastewater, can effectively remove hydrogen peroxide and lignin on the one hand, and avoid excessive papermaking wastewater addition causing an overload of the anaerobic system on the other hand, ultimately ensuring a high anaerobic removal rate.

[0133] (3) A comprehensive comparison of the data from Example 1 and Example 6-7 shows that the only difference between Example 6-7 and Example 1 is that the mass ratio of the water after primary sedimentation to the effluent from the secondary sedimentation tank is not within the preferred range of this invention. The anaerobic removal rate in Example 1 is significantly higher than that in Example 6-7. Thus, this invention, by optimally controlling the mass ratio of the water after primary sedimentation to the effluent from the secondary sedimentation tank, can further remove residual hydrogen peroxide and lignin on the one hand, and avoid adding too much effluent from the secondary sedimentation tank, which would cause the calcium ions, sulfate ions, etc. contained therein to affect the anaerobic removal rate. Furthermore, the effluent from the secondary sedimentation tank is the wastewater after biological treatment and has low biodegradability. Finally, the anaerobic removal rate is improved by controlling the mass ratio.

[0134] (4) A comprehensive comparison of the data from Example 1 and Examples 8-9 shows that the only difference between Examples 8-9 and Example 1 is that the mass ratio of the adjusted water to the secondary sedimentation tank effluent is not within the preferred range of this invention. The anaerobic removal rate in Example 1 is significantly higher than that in Examples 8-9. Thus, this invention, by optimally controlling the mass ratio of the adjusted water to the secondary sedimentation tank effluent, can further remove residual hydrogen peroxide and lignin on the one hand, and avoid adding too much secondary sedimentation tank effluent, which would cause the calcium ions, sulfate ions, etc. contained therein to affect the anaerobic removal rate. Furthermore, the secondary sedimentation tank effluent is the wastewater that has already undergone biological treatment and has low biodegradability. Finally, the anaerobic removal rate is improved by controlling the mass ratio.

[0135] (5) A comprehensive comparison of the data from Example 1 and Comparative Examples 1-4 shows that the anaerobic removal rate in Example 1 is significantly higher than that in Comparative Examples 1-4. The treatment method provided by the present invention can effectively remove hydrogen peroxide and lignin from pulping wastewater by adding papermaking wastewater to the coagulation treatment, adding secondary sedimentation tank effluent from the papermaking wastewater treatment system to the conditioning treatment, and not adding secondary sedimentation tank effluent from the papermaking wastewater treatment system to the pre-acidification treatment. This reduces the COD concentration entering the anaerobic reactor, thereby avoiding the influence of H2O2 and lignin on anaerobic microorganisms and improving the anaerobic removal rate.

[0136] In summary, the treatment method provided by this invention can reduce the harm of pollutants such as H2O2 and lignin in pulping wastewater to anaerobic bacteria, improve the anaerobic treatment effect, and reduce the COD content of the treated water, thus having application prospects and industrial value.

[0137] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A method for treating pulp mill effluent, characterized in that, The treatment method comprises the following steps: (1) mixing pulp mill wastewater and papermaking wastewater for coagulation treatment to obtain coagulated water; (2) the coagulated water obtained in step (1) is subjected to primary sedimentation treatment in a primary sedimentation tank to obtain primary sedimentation water; (3) the primary sedimentation water obtained in step (2) is subjected to adjustment treatment in a conditioning tank by mixing with the effluent from the secondary sedimentation tank of the papermaking wastewater treatment system to obtain adjusted water; (4) the adjusted water obtained in step (3) is subjected to pre-acidification treatment in a pre-acidification tank by mixing with the effluent from the secondary sedimentation tank of the papermaking wastewater treatment system to obtain pre-acidification water; (5) the pre-acidification water obtained in step (4) is subjected to anaerobic purification treatment in an anaerobic reactor to obtain treated water.

2. The treatment method according to claim 1, characterized in that, The content of H2O2 in the pulp mill wastewater is 10-30 mg / L.

3. The treatment method of claim 1, wherein The content of lignin in the pulp mill wastewater is 1500-2500 mg / L.

4. The treatment method of claim 1, wherein The COD concentration of the pulp mill wastewater is 15000-20000 mg / L.

5. The treatment method of claim 1, wherein The pH value of the pulp mill wastewater is 6-12.

6. The treatment method of claim 1, wherein The Fe content of the papermaking wastewater is 2-4 mg / L. 3+ mg / L.

7. The treatment method of claim 1, wherein Ca content of the papermaking wastewater 2+ 300-500 mg / L.

8. The treatment method of claim 1, wherein, The COD content of the papermaking wastewater is 7000-9000 mg / L.

9. The treatment method of claim 1, wherein, The Ca 2+ content of the effluent from the second sedimentation tank is 300-500 mg / L.

10. The treatment method of claim 1, wherein, The COD content of the effluent from the secondary sedimentation tank is ≤250 mg / L.

11. The treatment method of claim 1, wherein, In the coagulation treatment of step (1), the mass ratio of pulp mill wastewater to papermaking wastewater is 1:(1.5-2.5).

12. The processing method according to claim 11, wherein, The content of H2O2 in the coagulated water is 0-5 mg / L.

13. The processing method of claim 11, wherein, The content of lignin in the coagulated water is 0-500 mg / L.

14. The processing method of claim 11, wherein, The COD content of the coagulated water is 6000-10000 mg / L.

15. The treatment method of claim 1, wherein, In step (2), sludge is also produced at the bottom of the primary sedimentation tank.

16. The processing method according to claim 15, wherein, The sludge at the bottom of the primary sedimentation tank is discharged into a sludge treatment unit through a sludge discharge pipeline.

17. The treatment method of claim 1, wherein, In the adjustment treatment of step (3), the mass ratio of primary sedimentation water to the effluent from the secondary sedimentation tank of the papermaking wastewater treatment system is 1:(1-2).

18. The processing method according to claim 17, wherein, The content of lignin in the adjusted water is 0-100 mg / L.

19. The processing method according to claim 17, wherein The COD content of the adjusted water is 3000-5000 mg / L.

20. The processing method of claim 17, wherein, The content of H2O2 in the adjusted water is 0-2 mg / L.

21. The treatment method of claim 17, wherein, Sludge is also produced at the bottom of the conditioning tank.

22. The treatment method of claim 21, wherein, The sludge at the bottom of the conditioning tank is discharged into a sludge treatment unit through a sludge discharge pipeline.

23. The treatment method of claim 1, wherein, In the pre-acidification treatment of step (4), the mass ratio of adjusted water to the effluent from the secondary sedimentation tank of the papermaking wastewater treatment system is 1:(1-2).

24. The treatment method of claim 23, wherein, The content of lignin in the pre-acidification water is 0-30 mg / L.

25. The treatment method of claim 23, wherein, The COD content of the pre-acidification water is 2000-3000 mg / L.

26. The treatment method of claim 23, wherein, The pH value of the pre-acidification water is 6-7.

27. The method of processing according to claim 23, wherein, The wastewater in the pre-acidification treatment is recycled back to the pre-acidification tank.

28. The method of claim 23, wherein, Sludge is also produced at the bottom of the pre-acidification tank.

29. The treatment method of claim 28, wherein, The sludge at the bottom of the pre-acidification tank is discharged into a sludge treatment unit through a sludge discharge pipeline.

30. The method of claim 1, wherein, In the anaerobic purification treatment of step (5), the upper layer of wastewater is recycled back to the inlet of the anaerobic reactor.

31. The treatment method of claim 30, wherein, The percentage of the amount of recycled water to the amount of water at the inlet of the anaerobic reactor is 30-50%.

32. A system for treatment of pulp mill effluent, characterized in that The treatment device system is used for the treatment method of pulp mill wastewater as claimed in any one of claims 1-31. The processing device system comprises a coagulation tank, a primary sedimentation tank, a regulating tank, a pre-acidification tank and an anaerobic reactor connected in sequence along the wastewater flow direction; The inlet of the coagulation tank is connected with the pulp wastewater pipeline and the papermaking wastewater pipeline respectively; The inlet of the regulating tank is connected with the effluent pipeline of the primary sedimentation tank and the effluent pipeline of the secondary sedimentation tank of the papermaking wastewater treatment system respectively; The inlet of the pre-acidification tank is connected with the effluent pipeline of the regulating tank and the effluent pipeline of the secondary sedimentation tank of the papermaking wastewater treatment system respectively.

33. The processing device system of claim 32, wherein, The bottom sludge outlet of the primary sedimentation tank is connected with the sludge treatment unit through a sludge discharge pipeline.

34. The processing device system of claim 32, wherein, The bottom sludge outlet of the regulating tank is connected with the sludge treatment unit through a sludge discharge pipeline.

35. The processing device system of claim 32, wherein, The bottom sludge outlet of the pre-acidification tank is connected with the sludge treatment unit through a sludge discharge pipeline.

36. The processing device system of claim 32, wherein, The effluent outlet of the pre-acidification tank is connected with the inlet of the pre-acidification tank through a first reflux pipeline.

37. The processing device system of claim 32, wherein, The effluent outlet of the anaerobic reactor is connected with the inlet of the anaerobic reactor through a second reflux pipeline.

38. The processing device system of claim 32, wherein, The effluent outlet of the anaerobic reactor is also connected with a treated water effluent pipeline.

39. The processing device system of claim 32, wherein, The bottom inlet of the anaerobic reactor is connected with an anaerobic sludge supplement pipeline.

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