Wastewater treatment device for gasification section

Abstract

The utility model discloses a wastewater treatment device for a gasification section, and belongs to the technical field of wastewater treatment. Comprising a flocculation tank, an adjusting tank, an IMC biochemical tank, a middle water tank, a sand filter tank, a total detection tank, a sludge concentration tank, a sedimentation tank, an other wastewater collection tank, a mechanical seal water collection tank and a clean water tank, a sludge outlet of the IMC biochemical tank is connected with the sludge concentration tank, and the IMC biochemical tank, the middle water tank, the sand filter tank, the total detection tank and a municipal sewage pipe network are sequentially connected; the mechanical seal water collecting tank is used for collecting mechanical seal water, the other wastewater collecting tank is used for collecting other wastewater except ash removal water and mechanical seal water in a gasification section, the ash water tank, the flocculation tank, the sedimentation tank, the adjusting tank and the IMC biochemical tank are sequentially connected, the other wastewater collecting tank is connected with the adjusting tank, and a sludge outlet of the sedimentation tank is connected with the sludge concentration tank. A clear liquid outlet of the sludge thickening tank and the mechanical seal water collecting tank are connected with an inlet of the clear water tank; an outlet of the clear water tank is connected with the middle water tank.

Description

TECHNICAL FIELD

[0001] The utility model belongs to wastewater treatment technical field, especially relate to a wastewater treatment device of gasification section. BACKGROUND

[0002] Synthetic ammonia is synthesized by nitrogen and hydrogen, and hydrogen comes from coal gasification (synthesis gas). The gasification furnace uses raw coal to make coal water slurry, and the gasification agent is reacted with the coal slurry, and the synthesis gas after the reaction is sent to the synthetic ammonia system. In the gasification section, water and coal produce water gas, and a large amount of black water is also produced; the black water is treated to obtain grey water, and part of the grey water is recycled, and is discharged after a certain number of cycles.

[0003] The patent with the application number CN202322896860.5 discloses a water comprehensive utilization system of gasification section, which comprises a coal grinding water tank, a flash evaporator, a clarifier, a grey water tank and a filter, wherein the coal grinding water tank, the additive tank, the coal inlet belt and the conversion dilute ammonia water pipeline of the synthetic ammonia system are all connected with the feed chute of the coal mill, and the discharge port of the coal mill is connected with the gasification furnace; the black water outlet of the gasification furnace is connected with the feed inlet of the flash evaporator, and the synthesis gas outlet is connected with the synthetic ammonia system; the discharge outlet of the flash evaporator is connected with the clarifier, and the clarifier and the coal grinding water tank both overflow into the grey water tank; the slurry outlet of the clarifier is connected with the feed inlet of the filter, and the filtrate outlet of the filter is connected with the coal grinding water tank.

[0004] The parameters of the discharged grey water are as follows: ammonia nitrogen is about 250 mg / L, total nitrogen is about 280 mg / L, COD is about 450 mg / L, and total phosphorus is about 0.5 mg / L. It needs to be treated before being sent to the municipal sewage pipe network for treatment.

[0005] The patent with the application number CN202110940689.6 discloses a biochemical method for efficiently treating total nitrogen in wastewater, which comprises the following steps:

[0006] a. The coal gasification wastewater and each wastewater are uniformly adjusted and distributed in the adjusting tank to be between COD 400-600 mg / L and NH3-N 250-400 mg / L.

[0007] b. The wastewater in step a is pumped into the air flotation tank through the addition of flocculants and coagulants to further settle the fine coal ash particles in the wastewater, thereby reducing the influence of inorganic coal ash particles on the activity of subsequent flocculent sludge.

[0008] c. The wastewater obtained after step b is sent to the hydrolysis acidification tank to further improve the biodegradability of the wastewater and degrade macromolecular organic matter.

[0009] d. The temperature of the hydrolysis acidification tank is controlled at 30-40℃ by the heat energy of the coal gasification wastewater, and the organic nitrogen is degraded, and the ammonia nitrogen content is reduced by 6%-14%.

[0010] e. The wastewater obtained after step d is collected in an intermediate water tank and then pumped into the IMC biological treatment tank in batches by a booster pump.

[0011] f. In the IMC biological treatment tank, ammonia nitrogen and total nitrogen in the wastewater are aerated at intervals by jet aerators and blowers. The dissolved oxygen (DO) at each stage of the biological treatment is controlled. Short-range nitrifying and denitrifying bacteria that have been cultivated and domesticated are used to degrade ammonia nitrogen in the wastewater to below 2 mg / L and total nitrogen to below 5 mg / L.

[0012] g. The temperature of the IMC biological treatment tank should be controlled at 25-40℃; the sludge concentration (MLSS) should be 3000mg / L-8000mg / L; the pH should be controlled at 7.0-8.5 and the alkalinity at 50-250mg / L to ensure the inorganic carbon source and micro-oxidative environment required for denitrification; the carbon source required for denitrification should be added with a C / N ratio of 4.5-6:1 based on the wastewater before treatment.

[0013] h. Regularly discharge sludge from the IMC biological treatment tank to the sludge thickening tank using the sludge pump, and control the sludge age of the short-cut nitrification-denitrification biological sludge to 25-40 days.

[0014] i. The wastewater after biochemical treatment is discharged into the buffer tank through a decanter.

[0015] In existing technologies, all wastewater is sequentially treated by flotation, hydrolysis acidification, and biochemical treatment. This process is not only complex but also places a high load on the IMC biochemical tank, resulting in greater energy consumption. Summary of the Invention

[0016] To address the aforementioned problems, this utility model provides a wastewater treatment device for a gasification stage. Specifically, it simplifies the treatment process, reduces the load on the IMC biological treatment tank, and lowers energy consumption, taking into account the characteristics of ash water. The technical solution is as follows:

[0017] The utility model discloses a wastewater treatment device of gasification section, including flocculation pool, adjusting pool, IMC biochemical pool, intermediate pool, sand filter jar, total detection pool and sludge concentration pool, the sludge outlet of IMC biochemical pool is connected with sludge concentration pool, and IMC biochemical pool, intermediate pool, sand filter jar, total detection pool and municipal sewage pipe network are connected in proper order.

[0018] Further, the wastewater treatment device of gasification section in the utility model embodiment further includes flocculating agent adding structure, and the flocculating agent adding structure is connected with flocculation pool and sludge concentration pool.

[0019] Further, the wastewater treatment device of gasification section in the utility model embodiment further includes methanol storage tank and lye adding structure, and the methanol storage tank and lye adding structure are connected with IMC biochemical pool.

[0020] Specifically, the volume of the reaction pool in the utility model embodiment is 200m 3 , the volume of the settling tank is 1500m 3 , the volume of the adjusting pool is 2000m 3 , the volume of the IMC biochemical pool is 20000m 3 , the volume of the clear water tank is 200m 3 , the volume of the sludge concentration tank is 100m 3 , and the volume of the intermediate pool is 2000m 3 .

[0021] Among them, the drainage capacity of the clear water tank in the utility model embodiment is 15-25% of the drainage capacity of the IMC biochemical pool.

[0022] Further, the wastewater treatment device of gasification section in the utility model embodiment further includes disinfection pool, and the disinfection pool is arranged between sand filter jar and total detection pool, and the sand filter jar, disinfection pool and total detection pool are connected in proper order.

[0023] The beneficial effects brought by the technical scheme provided by the embodiment of the utility model are: the utility model embodiment provides a wastewater treatment device of gasification section, simplifies the treatment process (for the characteristics of grey water, does not carry out air flotation and acidification treatment, can only pass through settlement treatment), reduces the load of IMC biochemical pool, and reduces energy consumption. The wastewater of the gasification section is divided into three categories, which are: grey water, machine seal water and other wastewater; the treatment process of the grey water is the longest, and needs full-process treatment; the treatment process of the machine seal water (also including concentrated clear liquid, is relatively pure, and the solid content may not meet the discharge requirements) is the shortest, and only needs sand filtration; the treatment process of the other wastewater is moderate, and can also adjust the ammonia nitrogen ratio of the grey water. In addition, the feed flow of the adjusted IMC biochemical pool is stable, the stable carbon-nitrogen ratio of the incoming water is ensured, and the stable operation of the IMC biochemical pool is ensured.

[0024] Specifically, in the patent, for the IMC biochemical pool with an incoming water (after adjustment) of 3000m 3 / d, the treatment capacity can be reduced by about 600m 3 / d.

[0025] The indexes of the treated wastewater are: ammonia nitrogen less than 5mg / L, total nitrogen less than 15mg / L, COD less than 50mg / L, and total phosphorus less than 0.2mg / L, which completely meet the water quality indexes of the municipal pipe network. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 is a principle block diagram of an existing gasification section;

[0027] Figure 2 is a principle block diagram of the wastewater treatment device of the gasification section provided by embodiment 1. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical scheme and advantages of the utility model more clear, the utility model will be further described in detail in combination with the drawings.

[0029] Embodiment 1

[0030] Referring to Figure 2The embodiment 1 provides a wastewater treatment device of a gasification section, which comprises a flocculation tank, an adjusting tank, an IMC biochemical tank, an intermediate water tank, a sand filter tank, a total detection tank, a sludge concentration tank, a sedimentation tank, an other wastewater collection tank, a machine seal water collection tank, a clean water tank, a flocculant adding structure, a methanol storage tank, a lye adding structure and a disinfection tank, etc. The ash water is mixed with the flocculant in the flocculation tank, and a stirrer can be arranged in the flocculation tank. The sedimentation tank is used for sedimentation of the ash water. The adjusting tank is used for mixing the settled ash water and other wastewater and adjusting parameters such as ammonia nitrogen ratio to adapt to the IMC biochemical tank. The intermediate water tank is used for temporarily storing wastewater. The sand filter tank is used for filtration. The disinfection tank is used for disinfection. The total detection tank is used for detecting whether the indexes of the wastewater meet the standard. The sludge concentration tank is used for concentrating sludge by sedimentation. The methanol storage tank is used for providing methanol as a carbon source, and the methanol is used in the ammonia synthesis process (specifically, methanol washing), so that the methanol can be centrally purchased; the amount of the methanol is 0.8-1.0 kg / ton of wastewater. The flocculant adding structure is used for providing a flocculant such as PAC, and the amount of the flocculant is similar to that of the conventional technology. The lye adding structure is used for providing lye, and the lye comprises sodium carbonate solution or sodium hydroxide solution, etc., and is used for controlling the pH value to be 7.5-8.5. The machine seal water collection tank is used for collecting machine seal water, which is relatively clean. The other wastewater collection tank is used for collecting other wastewater of the gasification section except the ash water and the machine seal water, including flushing water, domestic sewage, etc.

[0031] The ash water tank, the flocculation tank, the sedimentation tank (clean liquid output), the adjusting tank, the IMC biochemical tank (clean liquid output), the intermediate water tank, the sand filter tank, the disinfection tank, the total detection tank and the municipal sewage pipe network are sequentially connected (according to needs, directly connected, connected through a pipeline or connected through a ditch, etc., the same below). The other wastewater collection tank is connected with the adjusting tank, the sludge outlet of the sedimentation tank and the sludge outlet of the IMC biochemical tank are both connected with the sludge concentration tank, the clean liquid outlet of the sludge concentration tank and the machine seal water collection tank are both connected with the inlet of the clean water tank, and the outlet of the clean water tank is connected with the intermediate water tank. The flocculant adding structure is connected with the flocculation tank and the sludge concentration tank through a pipeline. The methanol storage tank and the lye adding structure are connected with the IMC biochemical tank through a pipeline.

[0032] In the embodiment of the utility model, the drainage capacity of the clean water tank is 15-25% of the drainage capacity of the IMC biochemical tank.

[0033] Embodiment 2

[0034] The embodiment 2 provides a wastewater treatment device of a gasification section, which has basically the same structure as that of the embodiment 1, and the difference lies in that the volume of the reaction tank in the embodiment is 200 m 3 , the volume of the sedimentation tank is 1500 m 3 , the volume of the adjusting tank is 2000 m 3 , the volume of the IMC biochemical tank is 20000 m 3 , and the volume of the clean water tank is 200 m3 The volume of the sludge concentration tank is 100m 3 The volume of the intermediate water tank is 2000m 3 The inflow of the IMC biochemical tank is stable, being 3000m 3 / d; the flow of the clean water tank is unstable, being about 650m 3 / d in summer and about 450m 3 / d in winter. The average flow of the clean water tank is 600m 3 / d, which can save 840,000 yuan of electric energy and reduce 3,280,000 yuan of methanol cost per year compared with the prior art. In addition, the adjusted inflow of the IMC biochemical tank is stable, which ensures the stable carbon-nitrogen ratio of the incoming water and the stable operation of the IMC biochemical tank.

[0035] In the embodiment, pumps, flow meters or valves are arranged on the pipelines or trenches between the structures as required.

[0036] The above merely describes the preferred embodiments of the present application, and is not intended to limit the present application. 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 wastewater treatment device for a gasification section, comprising a flocculation tank, an equalization tank, an IMC biological treatment tank, an intermediate water tank, a sand filter tank, a total testing tank, and a sludge thickening tank, wherein the sludge outlet of the IMC biological treatment tank is connected to the sludge thickening tank, and the IMC biological treatment tank, the intermediate water tank, the sand filter tank, the total testing tank, and the municipal sewage network are connected in sequence; characterized in that, The device also includes a sedimentation tank, other wastewater collection tanks, mechanical seal water collection tanks, and clear water tanks. The mechanical seal water collection tanks are used to collect mechanical seal water. The other wastewater collection tanks are used to collect other wastewater from the gasification section, excluding ash water and mechanical seal water. Ash water tanks, flocculation tanks, sedimentation tanks, equalization tanks, and IMC biological treatment tanks are connected in sequence. The other wastewater collection tanks are connected to the equalization tanks. The sludge outlet of the sedimentation tank is connected to the sludge thickening tank. The clear liquid outlet of the sludge thickening tank and the mechanical seal water collection tank are both connected to the inlet of the clear water tank. The outlet of the clear water tank is connected to the intermediate water tank.

2. The wastewater treatment device for the gasification section according to claim 1, characterized in that, The device also includes a flocculant addition structure connected to the flocculation tank and the sludge thickening tank.

3. The wastewater treatment device for the gasification section according to claim 1, characterized in that, The device also includes a methanol storage tank and an alkali addition structure, which are connected to the IMC biochemical pool.

4. The wastewater treatment device for the gasification section according to claim 1, characterized in that, The volume of the reaction tank is 200m³. 3 The sedimentation tank has a volume of 1500m³. 3 The volume of the regulating tank is 2000 m³. 3 The volume of the IMC biochemical tank is 20,000 m³. 3 The volume of the clear water tank is 200m³. 3 The sludge thickening tank has a volume of 100m³. 3 The intermediate water tank has a volume of 2000 m³. 3 .

5. The wastewater treatment device for the gasification section according to claim 1, characterized in that, The drainage volume of the clear water tank is 15-25% of the drainage volume of the IMC biological treatment tank.

6. The wastewater treatment device for the gasification section according to claim 1, characterized in that, The device also includes a disinfection tank, which is located between the sand filter tank and the main testing tank, and the sand filter tank, disinfection tank and main testing tank are connected in sequence.

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