System for treating hydrogen peroxide purification wastewater

Abstract

The utility model relates to the technical field of sewage treatment and coal water slurry gasification, and provides a system for treating hydrogen peroxide purified wastewater, which comprises a methanol rectifying tower, an HDP wastewater cooler, an HDP wastewater neutralization tank, a mixed wastewater preparation tank, a raw coal bunker, a coal mill, a coal slurry tank and a gasification furnace, the methanol rectifying tower is connected with the HDP wastewater cooler, the HDP wastewater cooler is connected with the HDP wastewater neutralization tank, and the mixed wastewater preparation tank is connected with the coal slurry tank. The HDP wastewater neutralization tank is connected with a NaOH solution supply device, the HDP wastewater neutralization tank is connected with a mixed wastewater preparation tank, the mixed wastewater preparation tank is connected with a benzene extraction raffinate supply device and a nitrogen supply device, an additive supply device, a raw coal bunker and the mixed wastewater preparation tank are connected with a coal mill, the coal mill is connected with a coal slurry tank, and the coal slurry tank is connected with a gasification furnace. The system realizes preparation of the coal water slurry from HDP wastewater instead of fresh water, solves the problem of environment-friendly treatment of the HDP wastewater, realizes resource utilization of the wastewater, and reduces the production cost.

Description

Technical Field

[0001] The present application belongs to the technical field of sewage treatment and water-coal slurry gasification, and more specifically, to a system for treating hydrogen peroxide purified wastewater. Background Art

[0002] The hydrogen peroxide produced by the anthraquinone method contains 200-300 mg / L of organic impurities. The organic carbon in the hydrogen peroxide is removed by adsorption by macroporous adsorption resin to obtain industrial hydrogen peroxide that meets the standard. The adsorption-saturated macroporous resin is regenerated using methanol. The regenerated crude methanol is treated by distillation through a distillation tower to produce qualified methanol for the next regeneration step. During the methanol distillation process, a certain amount of wastewater will be generated at the bottom of the methanol distillation tower. The wastewater mainly contains a large amount of organic matter, and the COD content is as high as 80,000-120,000 mg / L, which is abbreviated as HDP wastewater.

[0003] At present, industrial wastewater treatment is the top problem for enterprises, and achieving zero-pollution green production has always been the goal pursued by enterprises. Biochemical methods are usually used to treat wastewater in industrialization, but biochemical methods are difficult to treat HDP wastewater, the effect is unstable, the resource utilization rate is low, and the production and operation costs of enterprises are increased. Therefore, how to simply and efficiently treat HDP wastewater or utilize the organic resources in it needs to be developed urgently.

[0004] Patent CN110342685A discloses a method for adsorbing COD in coal-to-methanol wastewater using macroporous resin. The adsorption characteristics of macroporous resin are used to remove COD from coal-to-methanol wastewater by adsorption treatment, and the removal rate can reach up to 76%. Although this method reduces the COD in the wastewater, it cannot completely dispose of the wastewater, and the saturated macroporous resin needs to be regenerated, which increases the processing steps and costs.

[0005] As a mature process technology for producing crude synthesis gas (CO+H2), water-coal slurry gasification technology is widely used in chemical production processes, and a series of wastewater slurry gasification technologies have been developed. Patent CN105482860A discloses a method for treating coal chemical methanol distillation wastewater. This method mixes methanol distillation wastewater, coal powder, activated sludge, dispersant, and a small amount of fresh water to prepare water-coal slurry. Patent CN108531221A discloses a process method for the coordinated disposal of industrial waste alkali liquor using a water-coal slurry gasifier. This method removes grease from industrial waste alkali liquor and mixes it with raw coal, additives and water to prepare water-coal slurry. The water-coal slurries prepared by the two methods can be sent to the gasifier to react and generate crude synthesis gas, thereby realizing waste recycling.

[0006] Therefore, how to prepare HDP wastewater into pulping water and prepare crude synthesis gas with coal co-gasification device to obtain industrial hydrogen production raw materials is a technical problem that needs to be solved urgently. Utility Model Content

[0007] In view of the deficiencies of the above-mentioned prior art, the purpose of the embodiments of the present application is to provide a system for treating hydrogen peroxide purified wastewater, which can effectively prepare HDP wastewater into pulping water and prepare crude synthesis gas with a coal co-gasification device to obtain industrial hydrogen production raw materials, that is, it treats wastewater containing high COD, effectively solves the problem of industrial wastewater treatment, and at the same time also realizes the secondary utilization of resources, reduces the production cost of the enterprise and improves the economic benefits.

[0008] To achieve the above-mentioned purpose, the technical solution adopted in the present application is: to provide a system for treating hydrogen peroxide purified wastewater, comprising: a methanol distillation tower, an HDP wastewater cooler, an HDP wastewater neutralization tank, a mixed wastewater preparation tank, a raw coal bin, an additive supply device, a coal mill, a coal slurry tank and a gasifier, the bottom of the methanol distillation tower is connected to the HDP wastewater cooler, the HDP wastewater cooler is cold connected to the HDP wastewater neutralization tank, the HDP wastewater neutralization tank is connected to a NaOH solution supply device, the HDP wastewater neutralization tank is connected to the mixed wastewater preparation tank, the mixed wastewater preparation tank is connected to a benzene extraction residual liquid supply device and a nitrogen supply device, the additive supply device, the raw coal bin and the mixed wastewater preparation tank are connected to the coal mill, the coal mill is connected to the coal slurry tank, and the coal slurry tank is connected to the gasifier.

[0009] In one embodiment, the HDP wastewater cooler cools the HDP wastewater to 50-70°C.

[0010] In one embodiment, the NaOH solution supply device provides 20% NaOH solution, and the pH value of the weakly alkaline HDP wastewater in the HDP wastewater neutralization tank is 7-9.

[0011] In one embodiment, the ratio of the benzene extraction residue to the weakly alkaline HDP wastewater in the mixed wastewater preparation tank is 1:5.

[0012] In one embodiment, a first water outlet pump is provided on the pipeline between the HDP wastewater cooler and the HDP wastewater neutralization tank, a second water outlet pump is provided on the pipeline between the HDP wastewater neutralization tank and the mixed wastewater preparation tank, and a third water outlet pump is provided on the pipeline between the mixed wastewater preparation tank and the coal mill.

[0013] In one embodiment, a weighing coal feeder is provided between the raw coal bin and the coal mill; the discharge port of the coal mill is connected to a discharge trough, a first discharge pump is provided on the pipeline between the discharge trough and the coal slurry trough, and a second discharge pump is provided on the pipeline between the coal slurry trough and the gasifier.

[0014] In one embodiment, a first flow regulating valve is provided on the pipeline between the HDP wastewater neutralization tank and the mixed wastewater preparation tank, a second flow regulating valve is provided on the pipeline between the mixed wastewater preparation tank and the coal mill; a third flow regulating valve is provided on the pipeline between the benzene extraction residual liquid supply device and the mixed wastewater preparation tank; and a fourth flow regulating valve is provided on the pipeline between the additive supply device and the coal mill.

[0015] The beneficial effect of the system for treating hydrogen peroxide purified wastewater provided in the present application is that the system can use HDP wastewater instead of fresh water to prepare water-coal slurry, which not only solves the problem of environmentally friendly treatment of HDP wastewater and achieves the purpose of harmless treatment, but also realizes the resource utilization of wastewater, reduces the production cost of water-coal slurry hydrogen production, and improves economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0017] Figure 1 A schematic diagram of the connection relationship structure of a system for treating hydrogen peroxide purified wastewater provided in an embodiment of the present application.

[0018] Among them, the reference numerals in the figure are:

[0019] 1. Methanol distillation tower; 2. HDP wastewater cooler; 3. First outlet pump; 4. HDP wastewater neutralization tank; 5. Second outlet pump; 6. Mixed wastewater preparation tank; 7. Third outlet pump; 8. Raw coal bin; 9. Weighing coal feeder; 10. Coal mill; 11. Discharge trough; 12. First discharge pump; 13. Coal slurry tank; 14. Second discharge pump; 15. Gasifier; 16. NaOH solution supply device; 17. Benzene extraction residual liquid supply device; 18. Additive supply device; 19. First flow control valve; 20. Second flow control valve; 21. Third flow control valve; 22. Fourth flow control valve; 23. Nitrogen supply device. DETAILED DESCRIPTION

[0020] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0021] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0022] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0023] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0024] like Figure 1 As shown, a system for treating hydrogen peroxide purified wastewater provided in an embodiment of the present application is now described. The system for treating hydrogen peroxide purified wastewater comprises: a methanol rectification tower 1, a HDP wastewater cooler 2, a HDP wastewater neutralization tank 4, a mixed wastewater preparation tank 6, a raw coal bin 8, an additive supply device 18, a coal mill 10, a coal slurry tank 13 and a gasifier 15.

[0025] Among them, HDP wastewater is generated at the bottom of the methanol distillation tower 1, and the bottom of the methanol distillation tower 1 is connected to the HDP wastewater cooler 2 through a pipeline. The HDP wastewater cooler 2 is used to cool the HDP wastewater. The cooled HDP wastewater is passed into the HDP wastewater neutralization tank 4. The HDP wastewater neutralization tank 4 is connected to a NaOH solution supply device 16, so that the HDP wastewater becomes weakly alkaline HDP wastewater; the HDP wastewater neutralization tank 4 is connected to a mixed wastewater preparation tank 6, and the mixed wastewater preparation tank 6 is connected to a benzene extraction residual liquid supply device 17 and a nitrogen supply device 23, and the weakly alkaline HDP wastewater and the benzene extraction residual liquid are mixed under the stirring of nitrogen to obtain mixed wastewater; the additive supply device 18, the raw coal bin 8 and the mixed wastewater preparation tank 6 are connected to the coal mill 10, and the coal mill 10 grinds and mixes the raw coal, the mixed wastewater and the additive solution to obtain water-coal slurry. The coal mill 10 is connected to the coal slurry tank 13, and the coal slurry tank 13 is connected to the gasifier 15, and the water-coal slurry prepares a crude synthesis gas in the gasifier 15.

[0026] The HDP wastewater cooler 2 cools the wastewater to 50-70° C. The NaOH solution supply device 16 provides a 20% NaOH solution, which adjusts the pH value of the HDP wastewater in the HDP wastewater neutralization tank 4 to 7-9.

[0027] The pH value of the benzene extract residue provided by the benzene extract residue supply device 17 is 7-9; the ratio of the benzene extract residue to the weakly alkaline HDP wastewater in the mixed wastewater preparation tank 6 is 1:5, and they are fully mixed under nitrogen stirring to obtain mixed wastewater. The benzene extract residue is an existing one, and its components contain 50,000 to 150,000 mg / L of COD, 0.1%wt caprolactam content, 2.1%wt organic matter (β-hydroxycyclohexanone, cyclohexanone oxime derivatives), 6.0%wt sodium sulfate and 35ppm benzene.

[0028] In this embodiment, a first water outlet pump 3 is provided on the pipeline between the HDP wastewater cooler 2 and the HDP wastewater neutralization tank 4, a second water outlet pump 5 is provided on the pipeline between the HDP wastewater neutralization tank 4 and the mixed wastewater preparation tank 6, and a third water outlet pump 7 is provided on the pipeline between the mixed wastewater preparation tank 6 and the coal mill 10; the first water outlet pump 3, the second water outlet pump 5 and the third water outlet pump 7 are used to realize the flow of wastewater.

[0029] In this embodiment, a weighing coal feeder 9 is provided between the raw coal bin 8 and the coal mill 10. The weighing coal feeder 9 is used to weigh the raw coal to facilitate confirmation of the ratio between the raw coal and the mixed wastewater and the additive solution, wherein the additive solution is the prior art, such as 0.2%-0.3% sodium lignin sulfonate. The discharge port of the coal mill 10 is connected with a discharge trough 11, which is used to receive the prepared water-coal slurry and acts as a buffer; a first discharge pump 12 is provided on the pipeline between the discharge trough 11 and the coal slurry trough 13, and a second discharge pump 14 is provided on the pipeline between the coal slurry trough 13 and the gasifier 15. The first discharge pump 12 and the second discharge pump 14 are used to realize the flow of the water-coal slurry.

[0030] In this embodiment, a first flow meter 19 is provided on the pipeline between the HDP wastewater neutralization tank 4 and the mixed wastewater preparation tank 6, which is used to confirm the amount of weakly alkaline HDP wastewater passed into the mixed wastewater preparation tank 6; a second flow regulating valve 20 is provided on the pipeline between the mixed wastewater preparation tank 6 and the coal mill 10, which is used to confirm the amount of mixed wastewater passed into the coal mill 10; a third flow regulating valve 21 is provided on the pipeline between the benzene extraction residual liquid supply device 17 and the mixed wastewater preparation tank 6, which is used to confirm the amount of benzene extraction residual liquid passed into the mixed wastewater preparation tank 6; a fourth flow regulating valve 22 is provided on the pipeline between the additive supply device 18 and the coal mill 10, which is used to confirm the amount of additive solution passed into the coal mill 10.

[0031] In this embodiment, the raw coal in the raw coal bin 8 includes Gucheng Coal Mine (HM077) and No. 2 High-quality Coal (HM152), which are mixed into coal powder in a ratio of 1:3.

[0032] Specifically, the properties of the water-coal slurry produced by the system are analyzed, and the specific details are shown in Table 1:

[0033] Table 1 Water-coal propeller performance test results

[0034]

[0035]

[0036] The results show that according to the co-gasification of the regenerated wastewater purified by hydrogen peroxide and coal proposed in this embodiment, the concentration of the finished water-coal slurry is 63.21%, the viscosity is 508 cP at 30°C, and the density is 1.115 kg / m 3 , pH value is 7.09, stability is grade B, fluidity is grade A, median diameter D50 is 52um, and all indicators meet the quality standards of water-coal slurry. In summary, the implementation of co-gasification of regenerated wastewater and coal after hydrogen peroxide purification can realize the utilization of organic resources in HDP wastewater.

[0037] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A system for treating hydrogen peroxide purified wastewater, characterized in that: include: A methanol distillation tower (1), a HDP wastewater cooler (2), a HDP wastewater neutralization tank (4), a mixed wastewater preparation tank (6), a raw coal bin (8), an additive supply device (18), a coal mill (10), a coal slurry tank (13) and a gasifier (15), wherein the bottom of the methanol distillation tower (1) is connected to the HDP wastewater cooler (2), the HDP wastewater cooler (2) is cold connected to the HDP wastewater neutralization tank (4), and the HDP wastewater neutralization tank (4) is connected to a NaOH solution. The HDP wastewater neutralization tank (4) is connected to the mixed wastewater preparation tank (6), the mixed wastewater preparation tank (6) is connected to a benzene extraction residual liquid supply device (17) and a nitrogen supply device (23), the additive supply device (18), the raw coal bin (8) and the mixed wastewater preparation tank (6) are connected to the coal mill (10), the coal mill (10) is connected to the coal slurry tank (13), and the coal slurry tank (13) is connected to the gasifier (15).

2. The system for treating hydrogen peroxide purified wastewater as claimed in claim 1, characterized in that: The HDP wastewater cooler (2) cools the HDP wastewater to 50-70°C.

3. The system for treating hydrogen peroxide purified wastewater as claimed in claim 1, characterized in that: The NaOH solution supply device (16) provides 20% NaOH solution, and the pH value of the weakly alkaline HDP wastewater in the HDP wastewater neutralization tank (4) is 7-9.

4. The system for treating hydrogen peroxide purified wastewater as claimed in claim 3, characterized in that: The ratio of the benzene extraction residue to the weakly alkaline HDP wastewater in the mixed wastewater preparation tank (6) is 1:

5.

5. The system for treating hydrogen peroxide purified wastewater as claimed in claim 1, characterized in that: A first water outlet pump (3) is provided on the pipeline between the HDP wastewater cooler (2) and the HDP wastewater neutralization tank (4), a second water outlet pump (5) is provided on the pipeline between the HDP wastewater neutralization tank (4) and the mixed wastewater preparation tank (6), and a third water outlet pump (7) is provided on the pipeline between the mixed wastewater preparation tank (6) and the coal mill (10).

6. The system for treating hydrogen peroxide purified wastewater according to any one of claims 1 to 5, characterized in that: A weighing coal feeder (9) is provided between the raw coal bin (8) and the coal mill (10); the discharge port of the coal mill (10) is connected to a discharge trough (11); a first discharge pump (12) is provided on a pipeline between the discharge trough (11) and the coal slurry trough (13); and a second discharge pump (14) is provided on a pipeline between the coal slurry trough (13) and the gasifier (15).

7. The system for treating hydrogen peroxide purified wastewater as claimed in claim 6, characterized in that: A first flow regulating valve (19) is provided on the pipeline between the HDP wastewater neutralization tank (4) and the mixed wastewater preparation tank (6), and a second flow regulating valve (20) is provided on the pipeline between the mixed wastewater preparation tank (6) and the coal mill (10); a third flow regulating valve (21) is provided on the pipeline between the benzene extraction residual liquid supply device (17) and the mixed wastewater preparation tank (6); and a fourth flow regulating valve (22) is provided on the pipeline between the additive supply device (18) and the coal mill (10).

Images