A device for resource utilization and treatment of TATB production wastewater

Abstract

The application discloses a TATB production wastewater resource utilization and treatment device and belongs to the field of explosive wastewater resource utilization. The application comprises an adjusting pool, a catalytic wet air oxidation device CWAO, an intermediate water tank, a membrane absorption device, an ammonium sulfate collecting tank, a water outlet tank, a biochemical system, an evaporation device and a pump. The TATB production wastewater is self-flowed into the adjusting pool, is uniformly and equally treated, is lifted into a sedimentation tank by a pump, and after removal of suspended matters, is lifted into the catalytic wet air oxidation device CWAO by the pump. Under high-temperature and high-pressure conditions, under the catalysis of a catalyst, toluene and aniline organic matters in the wastewater are degraded, high-ammonia-nitrogen wastewater containing a small amount of solvents is obtained, the catalytic wet air oxidation device CWAO outlet water flows into the intermediate water tank, and the intermediate water tank outlet water is sent into the membrane absorption device by a pump through a pipeline. Ammonia-nitrogen is separated from the wastewater by gas-phase membrane separation and sulfuric acid absorption, saturated ammonium sulfate solution and wastewater with B / C greater than or equal to 0.25 are obtained, and the wastewater can be discharged up to the standard.

Description

TECHNICAL FIELD

[0001] The present application relates to a TATB production wastewater resource utilization and treatment device, in particular to a physicochemical method for recycling ammonia nitrogen in TATB production wastewater and a TATB production wastewater treatment device, and belongs to the field of explosive wastewater resource utilization. BACKGROUND

[0002] The main pollutants of TATB production wastewater are toluene, triaminotri-nitrobenzene, trichlorotri-nitrobenzene, ammonia water, acetone and the like, the COD is 15000-25000 mg / L, the toluene concentration is 1000-200 mg / L, the ammonia nitrogen concentration is 15000-2000 mg / L, and B / C is less than 0.01. At present, the wastewater is treated by incineration, which has high cost and serious pollution.

[0003] CWAO has the characteristics of mild reaction condition, high treatment efficiency, fast reaction speed, recyclable resources and low secondary pollution, so it is called water treatment technology 4.0, which can effectively treat high-concentration organic wastewater. However, on the one hand, the inorganic salt in the wastewater has a toxic effect on the traditional commercial catalyst (RuO2 / TiO2), and on the other hand, in view of the high price of the noble metal catalyst, the development of salt-resistant and efficient CWAO catalysts is the key to the application of CWAO technology in the treatment of TATB wastewater.

[0004] At present, the modification of CWAO catalysts can be divided into two categories: one is optimization, mainly based on Ru-based catalyst modification. Ru itself has oxidation-reduction ability and stability, and the main problem is how to improve the dispersion of Ru and improve the oxygen capacity of the catalyst. Among them, TiO2-CeO2-RuO2 is considered to be an optimized system that can balance the dispersion of the catalyst and the oxygen capacity. The other is transition metal oxides. Due to the high price of noble metal catalysts, non-noble metal-based high-performance catalysts have always been the research focus of CWAO technology. Transition metals have unfilled d electron orbitals, which are easy to hybridize with O 2p electron orbitals, and have strong adsorption and activation of oxygen function, so they are used as active components in CWAO catalysts. However, this type of catalyst is a composite catalyst, and the adsorption of oxygen and substrates and the electron transfer between the active component and the oxidant need the combination of the carrier, the oxygen adsorption aid and the active substance to complete, which puts high requirements on the uniform distribution of the active component and the oxygen adsorption aid on the carrier, and the preparation process of the catalyst is required.

[0005] Perovskite oxides have excellent oxidation-reduction ability (B-site transition metals that are easy to change valence are usually redox couples Mn + / M (n-1)+The surface exchange and oxygen transport performance of the perovskite oxide and oxygen. Under certain conditions, the metal doped in the A site and B site of the perovskite oxide can realize in-situ desolventizing segregation, so that the nano-alloy particles are formed on the surface of the oxide, the nano-particles have high dispersibility and limited nature, the active components are ensured not to be aggregated and lost, and the catalytic activity and stability of the catalyst are improved to a certain extent. Therefore, based on the regulation mechanism of the perovskite oxide, the perovskite catalyst with multifunctional sites can be designed and prepared by reasonable doping modification and preparation process control, and the selective adsorption of organic matter and oxygen and the electron transfer between the oxidant and the active component are realized, the carrier and the additive are not needed, the preparation process of the catalyst is simplified, and the rate of the CWAO reaction is expected to be improved at the atomic level. SUMMARY

[0006] The application aims to provide a TATB production wastewater resource utilization and treatment device. The device can realize effective recovery and utilization of high-concentration ammonia nitrogen in TATB production wastewater and wastewater treatment, can obtain saturated ammonium sulfate solution, and can discharge wastewater B / C≥0.25. The saturated ammonium sulfate solution can be treated by evaporation to obtain ammonium sulfate solid, and the discharged wastewater can be discharged after biochemical treatment.

[0007] The application is realized by solving the following technical problems.

[0008] The application discloses a TATB production wastewater resource utilization and treatment device, which comprises a regulating tank, a catalytic wet air oxidation device CWAO, an intermediate water tank, a membrane absorption device, an ammonium sulfate collecting tank, a water outlet tank, a biochemical system, an evaporation device and a pump.

[0009] TATB production wastewater is self-flowed into the regulating tank, is uniformly and quantitatively treated, is lifted into a sedimentation tank by a pump, and after removal of suspended solids, is lifted into the catalytic wet air oxidation device CWAO by the pump. Under high temperature and high pressure conditions, toluene and aniline organic matter in the wastewater are degraded under the catalysis of a catalyst, high-ammonia-nitrogen wastewater containing a small amount of solvent is obtained, the catalytic wet air oxidation device CWAO outlet water flows into the intermediate water tank, and the intermediate water tank outlet water is sent into the membrane absorption device by a pump through a pipeline. Ammonia nitrogen is separated from the wastewater by gas-phase membrane separation and sulfuric acid absorption, saturated ammonium sulfate solution and wastewater with B / C≥0.25 are obtained.

[0010] Furthermore, for TATB production wastewater, the CWAO catalytic wet air oxidation unit employs a perovskite-type self-regenerating catalyst. This highly efficient perovskite catalyst possesses multifunctional sites, and the following three measures are used to improve the reaction rate and catalyst stability of CWAO in degrading organic matter: a. Introducing ions with high valence states and large ionic radii to reduce the poisoning of active atoms by inorganic salts, effectively protecting active atoms through steric hindrance, increasing the yield of hydroxyl radicals, and improving the degradation efficiency of organic pollutant molecules; b. Regulating the redox potential of active ions by controlling the ratio of introduced inert ions to active ions, thereby improving the TOC removal rate; c. Achieving high dispersion and confinement (preventing aggregation and loss) of active metal nanoparticles on the catalyst surface through in-situ desolvation of active components to improve electron transfer capacity and catalyst stability. The confinement refers to the resistance to aggregation and loss.

[0011] Preferably, the perovskite-type self-regenerating catalyst is CaMO3-type perovskite, and M is two or more of Mn, Fe, Co, Ni, Ti, Zr, Ru, Pt, and Pd.

[0012] As a further preferred option, the CaMO3-type perovskite self-regenerating catalyst is preferably CaFe. x Ru y Zr 1-x-y O 3-δ series.

[0013] As a preferred option, CaFe x Ru y Zr 1-x-y O 3-δ The series of perovskite-type self-regenerating catalysts were prepared by co-precipitation method, with x = 0.01 to 0.1 and y = 0.001 to 0.1 being preferred.

[0014] CaFe 0.05 Ru 0.05 Zr 0.9 O 3-δ The catalyst achieves a COD removal rate of over 80% and a toluene removal rate of over 99% for mixed toluene and aniline wastewater. The catalyst exhibits excellent stability, with a deactivation rate of <0.01% after 1000 hours of long-term operation.

[0015] The working method of the TATB production wastewater resource utilization and treatment device disclosed by the application is as follows: the TATB production wastewater is self-flowed into a regulating tank, is uniformly homogenized, is lifted into a sedimentation tank by a pump after removal of suspended solids, and is lifted into a catalytic wet air oxidation device (CWAO) by the pump after removal of suspended solids. The CWAO device is composed of a storage and delivery unit, a heat exchange unit, a reaction unit and a gas-liquid separation unit. Under high temperature and high pressure conditions, toluene and aniline substances are oxidized and decomposed into inorganic substances or small molecular organic substances by using air as an oxidant under the catalysis of a catalyst, and high ammonia-nitrogen wastewater containing a small amount of solvent is obtained. The CWAO effluent is self-flowed into an intermediate tank, and the intermediate tank effluent is sent into a membrane absorption device by a pump through a pipeline. The membrane absorption device is composed of a membrane absorption system mainly composed of a PTFE hollow fiber membrane assembly, an alkali adding system, an acid circulation system, an ammonium salt disposal system and a cleaning system. The CWAO effluent is in the membrane cavity, and H2SO4 absorption liquid is on the outside of the membrane. By adjusting the pH of the wastewater, the ionic NH4+ in the wastewater is converted into free volatile NH3. Under the driving of the concentration difference of NH3 on the inside and outside of the membrane, the NH3 in the wastewater volatilizes at the wastewater-microporous membrane interface. The gaseous NH3 diffuses along the membrane micropores to the other side of the membrane, is absorbed by the H2SO4 solution at the absorption liquid-microporous membrane interface, is rapidly reacted to generate non-volatile ammonium sulfate and is recovered. After the ammonium sulfate solution is saturated, the ammonium sulfate solution is discharged into an ammonium sulfate storage tank, and saturated ammonium sulfate and wastewater with B / C greater than or equal to 0.25 are obtained. The saturated ammonium sulfate enters an evaporation device, and solid ammonium sulfate is obtained after evaporation. The wastewater is subjected to subsequent biochemical treatment and is discharged up to the standard.

[0016] The application can realize TATB production wastewater resource utilization and treatment. After treatment by the device, saturated ammonium sulfate solution can be obtained, and the discharge wastewater has B / C greater than or equal to 0.25. After evaporation treatment of the saturated ammonium sulfate solution, solid ammonium sulfate can be obtained. After biochemical treatment of the discharge wastewater, the discharge wastewater can meet the standard requirements of the Water Quality Standard for Discharge of Sewage into Urban Sewer (GB / T31962-2015).

[0017] Advantages:

[0018] 1. The TATB production wastewater resource utilization and treatment device disclosed by the application adopts a CWAO device to pretreat TATB production wastewater, reduces the toluene concentration in the wastewater, maintains the ammonia-nitrogen concentration basically unchanged, avoids corrosion of toluene on PTFE hollow fiber membranes in a membrane absorption device, improves the service life of the membrane assembly and reduces the operation cost.

[0019] 2. The TATB production wastewater resource utilization and treatment device disclosed by the application can realize that high ammonia-nitrogen wastewater containing toluene is treated by the device to obtain saturated ammonium sulfate solution, and solid ammonium sulfate can be obtained after evaporation treatment.

[0020] 3.The TATB production wastewater resource utilization and treatment device disclosed in the application, after the wastewater is treated, the B / C is increased from 0.01 to 0.25 or above, the biodegradability is greatly improved, and the subsequent biochemical treatment conditions can be met.

[0021] 4.The TATB production wastewater resource utilization and treatment device disclosed in the application meets the standard treatment requirements of TATB production wastewater, and after the wastewater is treated, the wastewater can meet the standard requirements of the water quality standard for wastewater discharge into urban sewers (GB / T31962-2015). BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 The device schematic diagram of Example 1. DETAILED DESCRIPTION

[0023] The application will be further explained in combination with the drawings and examples.

[0024] Example 1

[0025] The TATB production wastewater resource utilization and treatment device disclosed in the example comprises a regulating tank, a catalytic wet air oxidation device, an intermediate water tank, a membrane absorption device, an ammonium sulfate collection tank, a water outlet tank and a pump.

[0026] The TATB production wastewater is self-flowed into the regulating tank, is lifted into the sedimentation tank by the pump, is lifted into the catalytic wet air oxidation device (CWAO) by the pump, the CWAO effluent is self-flowed into the intermediate water tank, the intermediate water tank effluent is sent into the membrane absorption device by the pump through the pipeline, the saturated ammonium sulfate solution in the membrane absorption device is entered into the collection tank, and the effluent is entered into the water outlet tank.

[0027] The collected wastewater has a COD of 21770 mg / L, an ammonia nitrogen of 5580 mg / L and a toluene concentration of 580 mg / L.

[0028] 50 L of TATB production wastewater is flowed into the wastewater regulating tank, is homogenized and quantified, is lifted into the sedimentation tank by the pump, is lifted into the catalytic wet air oxidation device (CWAO) by the pump after the suspended solids are removed, the CWAO device is composed of a storage and delivery unit, a heat exchange unit, a reaction unit and a gas-liquid separation unit, under the conditions of high temperature and high pressure, toluene and aniline substances are oxidized and decomposed into inorganic substances or small molecular organic substances by taking air as an oxidant under the catalysis of the catalyst, high ammonia nitrogen wastewater containing a small amount of solvent is obtained, the CWAO effluent is self-flowed into the intermediate water tank, the intermediate water tank effluent is sent into the membrane absorption device by the pump through the pipeline, the membrane absorption device is composed of a membrane absorption system mainly composed of a PTFE hollow fiber membrane assembly, an alkali adding system, an acid circulation system, an ammonium salt disposal system and a cleaning system, the CWAO effluent is in the membrane cavity, and the H2SO4 absorption liquid is on the outside of the membrane, the ion state NH4 +NH3 is converted into free volatile NH3. NH3 in wastewater is volatilized at the wastewater-microporous membrane interface driven by the concentration difference of NH3 between the inside and outside of the membrane. Gaseous NH3 diffuses along the microporous membrane to the other side of the membrane and is absorbed by H2SO4 solution at the absorption liquid-microporous membrane interface, rapidly reacts to generate non-volatile ammonium sulfate and is recovered, and the ammonium sulfate solution is saturated and discharged into the ammonium sulfate storage tank to obtain saturated ammonium sulfate and wastewater with a B / C of 0.29. The saturated ammonium sulfate enters the evaporation device and solid ammonium sulfate is obtained after evaporation, and the wastewater is treated by subsequent biochemical treatment and meets the discharge standard.

[0029] The specific implementation data of wastewater treatment are as follows:

[0030]

[0031] Example 2

[0032] CaFe2O4 was synthesized by co-precipitation method 0.05 Ru 0.05 Zr 0.9 O 3-δ The catalyst was used for TATB production wastewater treatment, and the wastewater had a COD of 21770 mg / L, an ammonia nitrogen of 5580 mg / L and a toluene concentration of 580 mg / L. The treatment effect of the catalytic wet oxidation unit was as follows:

[0033] COD (mg / L) Toluene (mg / L) Raw water quality 21770 580 Catalytic wet oxidation unit 3045 ≤0.02

[0034] Example 3

[0035] CaFe2O4 was synthesized by co-precipitation method 0.05 Ru 0.01 Zr 0.94 O 3-δ The catalyst was used for TATB production wastewater treatment, and the wastewater had a COD of 21770 mg / L, an ammonia nitrogen of 5580 mg / L and a toluene concentration of 580 mg / L. The treatment effect of the catalytic wet oxidation unit was as follows:

[0036] COD (mg / L) Toluene (mg / L) Raw water quality 21770 580 Catalytic wet oxidation unit 4087 ≤0.02

[0037] Example 3

[0038] CaFe2O4 was synthesized by co-precipitation method 0.08 Ru 0.03 Zr 0.89 O 3-δ The catalyst was used for TATB production wastewater treatment, and the wastewater had a COD of 21770 mg / L, an ammonia nitrogen of 5580 mg / L and a toluene concentration of 580 mg / L. The treatment effect of the catalytic wet oxidation unit was as follows:

[0039] COD (mg / L) Toluene (mg / L) Raw water quality 21770 580 Catalytic wet oxidation unit 3846 ≤0.02

[0040] Example 4

[0041] CaFe 0.05 Ru 0.05 Zr 0.9 O 3-δ The catalyst was used for treating TATB production wastewater, and the wastewater had COD of 21770 mg / L, ammonia nitrogen of 5580 mg / L and toluene concentration of 580 mg / L. The results of the stability experiment of the catalytic wet oxidation unit catalyst are as follows:

[0042] Reaction time / h COD mg / L COD removal rate (%) Toluene (mg / L) 24 3038 86.0 ≤0.02 72 3026 86.1 ≤0.02 120 3017 86.1 ≤0.02 168 3040 86.0 ≤0.02 216 2998 86.2 ≤0.02 264 3019 86.1 ≤0.02 312 3024 86.1 ≤0.02 360 3018 86.1 ≤0.02 408 3008 86.2 ≤0.02 456 3011 86.2 ≤0.02 504 3018 86.1 ≤0.02 552 3012 86.2 ≤0.02 600 2996 86.2 ≤0.02 648 2992 86.3 ≤0.02 696 3022 86.1 ≤0.02 744 3031 86.1 ≤0.02 792 3041 86.0 ≤0.02 840 3032 86.1 ≤0.02 888 3012 86.2 ≤0.02 936 3026 86.1 ≤0.02 984 3017 86.1 ≤0.02 1032 3026 86.1 ≤0.02

[0043] The above detailed description further describes the purpose, technical scheme and beneficial effects of the application, and it should be understood that the above description is only a specific embodiment of the application and is not used to limit the protection scope of the application. Any modification, equivalent replacement, improvement, etc. within the spirit and principle of the application should be included in the protection scope of the application.

Claims

1. A device for the resource utilization and treatment of TATB production wastewater, characterized in that: It includes a conditioning tank, a catalytic wet air oxidation (CWAO) unit, an intermediate water tank, a membrane absorption unit, an ammonium sulfate collection tank, an effluent tank, a biochemical system, an evaporation unit, and pumps; TATB production wastewater flows by gravity into an equalization tank. After homogenization and equalization, it is pumped into a sedimentation tank to remove suspended solids. Then, it is pumped into a catalytic wet air oxidation (CWAO) unit. Under high temperature and high pressure conditions, and with the catalysis of a catalyst, toluene and aniline-based organic compounds in the wastewater are degraded, resulting in high ammonia nitrogen wastewater containing trace amounts of solvent. The effluent from the CWAO unit flows into an intermediate water tank, and the effluent from the intermediate water tank is pumped through pipelines to a membrane absorption unit. Ammonia nitrogen is separated from the wastewater using gas-phase membrane separation and sulfuric acid absorption, yielding a saturated ammonium sulfate solution and wastewater with a B / C ratio ≥ 0.

25. For TATB production wastewater, the CWAO catalytic wet air oxidation unit uses a perovskite-type self-regenerating catalyst for catalysis; the high-efficiency perovskite-type catalyst has multiple sites; The CaMO3-type perovskite self-regenerating catalyst is CaFe x Ru y Zr 1-x-y O 3-δ series; CaFe x Ru y Zr 1-x-y O 3-δ The series of perovskite-type self-regenerating catalysts were prepared by co-precipitation method, with x=0.01~0.1 and y=0.001~0.

1.

2. The TATB production wastewater resource utilization and treatment device as described in claim 1, characterized in that: The following three measures are adopted to improve the reaction rate and catalyst stability of CWAO in degrading organic matter: a. Introducing ions with high valence and large ionic radius to reduce the poisoning of active atoms by inorganic salts, effectively protecting active atoms through steric hindrance, increasing the yield of hydroxyl radicals, and improving the degradation efficiency of organic pollutant molecules; b. Regulating the redox potential of active ions by controlling the ratio of introduced inert ions to active ions, thereby improving the removal rate of TOC. c. High dispersion and confinement of active metal nanoparticles on the catalyst surface are achieved by in-situ desolvation of active components to improve electron transfer capability and catalyst stability; the confinement refers to the resistance to agglomeration and loss.

3. The TATB production wastewater resource utilization and treatment device as described in claim 1, characterized in that: CaFe 0.05 Ru 0.05 Zr 0.9 O 3-δ The catalyst achieves a COD removal rate of over 80% and a toluene removal rate of over 99% for mixed toluene and aniline wastewater.

4. The TATB production wastewater resource utilization and treatment device as described in claim 3, characterized in that: CaFe 0.05 Ru 0.05 Zr 0.9 O 3-δ The catalyst, after 1000 hours of long-term operation, showed a catalyst deactivation rate of <0.01%.

5. The TATB production wastewater resource utilization and treatment device as described in claim 4, characterized in that: CaFe 0.05 Ru 0.05 Zr 0.9 O 3-δ The catalyst achieves a COD removal rate of over 80% and a toluene removal rate of over 99% for mixed toluene and aniline wastewater.

6. A device for resource utilization and treatment of TATB production wastewater as described in any one of claims 1-5, characterized in that: TATB production wastewater flows by gravity into an equalization tank. After homogenization and equalization, it is pumped into a sedimentation tank to remove suspended solids. Then, it is pumped into a catalytic wet air oxidation (CWAO) unit. The CWAO unit consists of a storage unit, a heat exchange unit, a reaction unit, and a gas-liquid separation unit. Under high temperature and pressure conditions, and with the catalysis of a catalyst, air is used as the oxidant to oxidize and decompose toluene and aniline compounds into inorganic or small-molecule organic compounds, resulting in high-ammonia nitrogen wastewater containing trace amounts of solvent. The CWAO effluent flows by gravity into an intermediate water tank. The effluent from the intermediate water tank is pumped through pipelines to a membrane absorption unit. The membrane absorption unit mainly consists of a PTFE hollow fiber membrane module, an alkali addition system, an acid circulation system, an ammonium salt treatment system, and a cleaning system. The membrane chamber contains the CWAO effluent, and the outer side contains H2SO4 absorbent. By adjusting the pH of the wastewater, the ionic NH4+ in the wastewater is reduced. + The NH3 in the wastewater is converted into free volatile NH3. Driven by the concentration difference of NH3 inside and outside the membrane, the NH3 in the wastewater volatilizes at the wastewater-microporous membrane interface. The gaseous NH3 diffuses along the membrane micropores to the other side of the membrane and is absorbed by H2SO4 solution at the absorbent-microporous membrane interface. It reacts rapidly to form non-volatile ammonium sulfate and is recovered. After the ammonium sulfate solution is saturated, it is discharged into the ammonium sulfate storage tank to obtain saturated ammonium sulfate and wastewater with B / C ≥ 0.

25. The saturated ammonium sulfate enters the evaporation device and is evaporated to obtain solid ammonium sulfate. The wastewater is discharged after subsequent biochemical treatment to meet the standards.

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