CN108002642A - A kind of viscose fiber wastewater, sludge, the system and method for exhaust-gas treatment - Google Patents

Abstract

The invention discloses a system and method for treating viscose fiber waste water, sludge and waste gas, comprising the following steps: (1) collecting acid waste water and alkaline waste water; Degrade organic matter; (3) neutralize the water treated in step (2) for precipitation, add coagulants and coagulants to promote the aggregation of particles in the water; (4) put the water treated in step (3) into The cascade aeration tank is aerated, and the effluent meets the discharge standard for discharge; (5) the sludge generated in each step is processed, and the supernatant enters step (2) for processing; (6) the waste gas generated in each step is processed, Discharge up to standard after treatment. The method effectively treats waste water, sludge and waste gas produced by viscose fibers, has stable removal effect, low operating cost, high safety factor and high treatment efficiency, and has wide popularization value.

Description

A system and method for viscose fiber wastewater, sludge and waste gas treatment

technical field

The invention discloses a system and method for treating viscose fiber wastewater, sludge and waste gas, belonging to the field of viscose industry wastewater, sludge and waste gas treatment.

technical background

Viscose fiber is a chemical fiber processed by chemical and mechanical methods using polymer materials containing natural cellulose such as wood pulp and cotton pulp. One of the important materials of raw materials. The production process of viscose filament is: pulp dipping bath caustic soda solution to produce alkali cellulose, alkali cellulose reacts with carbon disulfide to produce sodium cellulose sulfonate (called sulfonation) sodium cellulose sulfonate is then dissolved in dilute sodium hydroxide Solution, into mucus, called viscose. The viscose can be sent to the spinning machine after being filtered, defoamed and matured. Spinning in the spinning workshop, when the viscose enters the coagulation bath (mainly composed of sulfuric acid, sodium sulfate and zinc sulfate, also known as sulfuric acid bath) of the spinning machine through the spinneret of the spinning machine, the viscose solidifies into filaments form, regenerated into cellulose, and processed after the well to leave the factory. The reaction of viscose to regenerate cellulose in acid bath will release hydrogen sulfide and carbon disulfide, which are the main sources of sulfide and carbon disulfide in fiber production wastewater.

Wastewater from viscose fiber factories can be divided into two categories: acidic wastewater and alkaline wastewater.

(1) Acidic wastewater: Acidic wastewater mainly comes from spinning workshops and acid stations, including plasticizing bath overflow discharge water, washing and spinning machine water, acid station washing and filtering drainage, silk washing water and post-treatment pickling water. The main pollutants of acid wastewater are sulfuric acid and zinc sulfate.

(2) Alkaline wastewater: Alkaline wastewater comes from the drainage of the alkali station, the waste glue tank of the stock solution workshop and the washing water of the equipment, the washing water of the filter cloth, the viscose brought out when the spinning machine replaces the filter and the spinneret, and the washing of the spinning machine Filter several spinneret water, post-treatment process desulfurization wastewater. The main pollutants of alkaline wastewater are sodium hydroxide and viscose.

Due to the complex composition of viscose industry wastewater, it often contains strong acid, strong alkali, cellulose and hemicellulose, alcohols, pectin and various organic poisons, so its biodegradability is poor, and the concentration of sulfide and zinc ions is high. 1. When the treatment system is running, there will be hydrogen sulfide and other peculiar smells, which will easily cause serious pollution to the environment and constantly threaten human health and safety. Therefore, how to achieve efficient and stable treatment of viscose fiber wastewater, sludge, and waste gas is an urgent problem to be solved.

There are still big problems in wastewater treatment technology in viscose fiber production, mainly reflected in the low efficiency, high cost, limited application of treatment methods, and easy to produce refractory pollutants. The physicochemical methods such as ozone oxidation method, electrocoagulation method, adsorption method, ion exchange method, membrane filtration method and flocculation method which are most used now have certain shortcomings.

The Chinese patent with the publication number CN 104310679 A provides a method for treating viscose fiber wastewater by chemically oxidizing organic matter in wastewater by the Fenton method. The oxidant is hydrogen peroxide with a mass fraction of 27.5%, and the catalyst is ferrous sulfate, hydrogen peroxide and sulfuric acid. The mass ratio of ferrous iron is 1:1, but the Fenton method has the following disadvantages: (1) high cost and large sludge output; (2) the treatment effect is unstable, if the mass ratio of hydrogen peroxide and ferrous sulfate is If the control is not good or the ferric iron does not precipitate, it will easily cause the wastewater to be slightly yellow, and the water body will turn back to color; (3) the reaction is difficult to control, and it is easily affected by factors such as the reaction pH value, time, and mixing degree; (4) High corrosiveness, easy to cause strong corrosion to equipment. (5) Exhaust gas treatment is not involved.

The Chinese patent with the publication number CN 105110575 A provides a viscose fiber industrial wastewater treatment method and device, which separately treats high-salt and low-salt wastewater according to the salinity of the viscous wastewater, and the process is complex and difficult to operate. Difficulty, low processing efficiency. In addition, in the "continuous microfiltration + reverse osmosis membrane double-membrane" unit designed in this treatment process, the operating cost of the membrane is too high, cleaning is difficult, and concentrated water treatment is difficult. Chambolle et al. point out that membrane treatment typically costs 20–30% more than direct filtration. Moulin et al. proposed that the investment cost of groundwater MF is 1.5-2 times of conventional treatment, and for surface water, the investment cost is 3-5 times of conventional treatment.

The Chinese patent with the publication number CN 103864260 A provides a treatment method for viscose fiber production wastewater. The main process of the process is: stripping reaction process → shallow air flotation process → iron filings filtration process → mixed reaction process → biological Processing procedure. This process does not use high-gas water for mixing and stirring, which fails to increase the reaction rate and cannot guarantee the subsequent treatment effect. In addition, if the waste gas H ₂ S and CS ₂ blown off by this process are not treated, if they are directly released into the environment, they will cause certain pollution and harm to the human body and the atmosphere, and the real clean production has not been achieved.

Publication number is that the Chinese patent of CN 1583608 A provides a kind of comprehensive treatment method of cotton pulp black liquor water, viscose fiber production wastewater, the aeration method involved in this process is only traditional aeration process, compared with the present invention And the "cascaded aeration process", the treatment effect of this process is not good.

The Chinese patent with the publication number CN 101343124 A provides a method and equipment for comprehensively treating waste water and waste gas in the production of viscose fiber. In this process, the continuous problem of gas-liquid two-phase reaction is not considered, that is, the final actual absorption of gas and Except for the effect, there is no guarantee that the gas will be completely reacted and absorbed, and the follow-up effect cannot be guaranteed. The patent of the present invention not only includes the method of lye absorption mentioned in this process, but also considers the utilization of subsequent gas, that is, the "biological filter bed process" is added to realize the comprehensive recycling of energy.

At present, most of the conventional "physicochemical + biochemical" treatment processes used in China have many problems, such as the low degree of automation control in the early stage of physical and chemical treatment, unstable operation results, and obvious inhibition of microbial growth. In addition, in the treatment of most viscose wastewater in China, there is no systematic and comprehensive treatment and utilization of hydrogen sulfide, carbon dioxide and other waste gases generated during the production process, that is, there is a lack of further treatment measures after lye spraying. In the aeration reaction tank for the treatment of viscose wastewater, the method of "cascade aeration" is rarely used. The cascade aeration can maximize the combination of fluid characteristics and mechanical movement, effectively eliminate the dead angle of stirring, and obtain large area of water exchange. In particular, in the field of viscose fiber wastewater treatment, the comprehensive cycle treatment process for wastewater, waste gas, and sludge is seldom described, and an economical and environmentally friendly system treatment method has not been proposed, resulting in waste of energy. Disjointed and the final handling is poor.

Considering the above points comprehensively, the patent of the present invention proposes a simple, economical, low energy consumption, and excellent treatment effect comprehensive circulation viscose wastewater treatment and recycling method, and the application of reclaimed water reuse technology in engineering practice is of great significance.

Contents of the invention

Purpose of the invention: To provide a kind of viscose fiber wastewater, sludge, The system and method of waste gas treatment realize the efficient treatment and stable compliance of waste water, sludge and waste gas in the viscose industry.

Technical solution: In order to achieve the above technical purpose, the present invention proposes a system for the treatment of viscose fiber wastewater, sludge and waste gas, including sump A, sump B, aeration stripping pool, neutralization reaction pool, primary sedimentation tank, pH adjustment tank, aeration tank, secondary settling tank, sludge concentration tank, odor source collection system, air distribution pipeline system and biological filter bed, of which:

The sump A and the sump B are respectively connected with the aeration and stripping tanks,

The aeration blow-off tank is sequentially connected with a neutralization reaction tank, a primary sedimentation tank, a pH adjustment tank, an aeration tank, a secondary sedimentation tank, and a sludge concentration tank;

The odor source collection system is used to collect the waste gas from the aeration stripping tank, the neutralization reaction tank, the aeration tank and the sludge thickening tank, and the collected waste gas is sent to the packing layer of the lye spray tower and the Active soil filter bed. Preferably, the induced draft fan adopts a centrifugal fan to reduce noise.

Specifically, an air agitation device is installed inside the aeration blow-off tank, a glass fiber reinforced plastic gas collecting hood is arranged above to collect the waste gas generated during the blow-off process, and a sedimentation device is installed at the bottom to precipitate the semi-fibers from acid precipitation. Toxins and oily substances, etc., and the sedimented sludge enters the sludge thickening tank.

The neutralization reaction tank includes a reaction zone and a sedimentation zone. The neutralization reaction sedimentation tank is equipped with a glass fiber reinforced plastic gas collection hood, wherein the sedimentation zone adopts a flat-flow sedimentation tank type for efficient separation of mud and water.

The aeration of the cascade aeration tank adopts the aeration and stirring device with double-layer impellers, and according to the flow of the water body, water is designed to enter from the center of the impeller, and the cascade aeration tank is equipped with a glass fiber reinforced plastic gas collection cover.

The biological filter bed is composed of a gravel supporting layer, an ecological filter layer and a soil layer arranged in sequence. Plants are planted in the soil layer, wherein the gravel supporting layer is 0.2-0.5m in height and 8-16mm in particle size; the ecological filter layer is 0.6 in height. -0.8m, particle size 2-4mm; soil layer height 0.2-0.5m, particle size less than 0.01mm.

There are 5 sprinklers arranged on the top of the biological filter bed, and the water consumption of each sprinkler is 0.4-0.6m ³ /h, one of which is used for humidification, and the other four are used for green irrigation; the plants include rushes, iris and reeds, the planting ratio is 1:1:1, and the planting density is not less than 16 plants/m ² .

The present invention further proposes a method for viscose fiber waste water, sludge, waste gas treatment, comprising the steps:

(1) Collect acidic wastewater and alkaline wastewater: through separate pipelines, respectively collect acidic wastewater and alkaline wastewater, acidic wastewater volume: alkaline wastewater volume ratio (3-5): 1;

(2) Aeration and blow-off: introduce the water obtained in step (1) into the aeration and blow-off tank, the aeration intensity is 10-15m ³ /m ² ·h, the residence time is 0.8-1.0h, and the pH is about 2-3. Use high steam-water ratio for mixing and stirring to increase the reaction speed and effect in the aeration blowing tank. Under acidic conditions, the waste gas in the waste water is blown off, and the waste gas generated during the blow-off process is collected, and the precipitated sludge precipitated by the precipitation acid enters the sludge thickening tank;

(3) neutralization reaction precipitation: the water of step (2) gained is introduced into the neutralization reaction sedimentation tank, and at first dosing purity is 85-88% ferrous sulfate to further reduce the sulfide content in the reaction zone of the neutralization reaction sedimentation tank, Because ferrous sulfate has a strong redox property, the removal rate of sulfide is very high, and its cost is low, and it has a good decolorization effect. On the one hand, the divalent iron ions (Fe ²⁺ ) generated by hydrolysis after ferrous sulfate is added to wastewater will react with sulfur ions (S ²⁻ ) to form iron sulfide (FeS) and precipitate into sludge. On the other hand, after ferrous sulfate is put into the wastewater, the complex produced by its hydrolysis, under the action of hydraulic stirring conditions, will pass the sulfur ions and other pollutant suspended matter in the wastewater through a series of adsorption-electroneutralization -The net capture-polymerization reaction promotes the sulfide to form iron sulfide, and finally aggregates with other organic pollutants to form alum flowers, which precipitate under the action of gravity to form dense sludge. After adding calcium carbide slag with a purity of 11-15% to increase the pH value of the wastewater to 9.5-10.5, the dosage of calcium carbide slag: 0.9-1.2kg/ ^m3 sewage, forming an alkaline precipitate of Zn ²⁺ ; followed by adding polypropylene Amide PAM, the dosage is 3-10mg/L, through charge neutralization, it can reduce the kinetic potential and coagulate, which enhances the flocculation effect of water. The reaction zone improves the coagulation and coagulation effect through aeration, the aeration intensity is 5-7m ³ /m ² ·h, and the residence time is 0.5-1.0h;

The sedimentation area of the neutralization reaction sedimentation tank adopts the type of advection sedimentation tank to efficiently separate mud and water. The floc particles formed are larger and easier to settle, which can achieve a better effect of removing COD and refractory organic matter; surface load 1.0～1.5m ³ /m ² ·h, the sedimented sludge enters the sludge thickening tank, and the waste gas generated during the collection and reaction precipitation process is collected;

(4) Cascade aeration tank

The water obtained in step (3) is introduced into the step aeration process, which is divided into grade I, grade II and grade III, respectively:

Level Ⅰ: Dissolved oxygen 0.5-2.0mg/L, residence time 3-6h, and add attapulgite adsorbent;

Grade II: dissolved oxygen 3.5-4.5mg/L, residence time 6-8h;

Level III: Dissolved oxygen 4.6-5.5mg/L, residence time 1-2h; effluent meets the discharge standard for standard discharge;

The aeration of the cascade aeration tank adopts the aeration and stirring device of the double-layer impeller, which combines the fluid characteristics and the mechanical movement to the greatest extent. According to the flow of water body, the water is designed to enter from the center of the impeller. On the one hand, it reduces the turbulence of the water intake, and on the other hand, it ensures that the pressure of the liquid on the surface of the impeller is uniform, so as to ensure the balance of the whole machine in a moving state. Effectively eliminate the dead angle of stirring. The large specific surface area can obtain a large area of water exchange. A glass fiber reinforced plastic gas collecting hood is installed on the cascade aeration tank to collect the exhaust gas during the aeration process.

(5) Sludge treatment:

The sludge from the aeration stripping tank, neutralization reaction sedimentation tank, and cascade aeration tank is discharged into the sludge thickening tank, and after being concentrated, the chamber filter press is used for mechanical dehydration. The supernatant and sewage of the sludge thickening tank The supernatant of the mud dewatering machine is returned to the aeration blowing tank;

(6) Exhaust gas treatment:

The exhaust gas collected from the aeration stripping tank, neutralization reaction sedimentation tank, cascade aeration tank and sludge thickening tank enters the lye spray tower through the induced draft fan, passes through the lye spray tower packing layer, and the waste gas is oxidized with hydrogen The sodium absorption liquid is fully contacted with the gas-liquid two-phase absorption neutralization reaction. After the acid mist exhaust gas is purified, it is dehydrated and defogged by the defogging plate and then discharged into the biological filter bed by the fan. The absorption liquid is pressurized by the water pump at the bottom of the tower. The top of the tower is sprayed down, and finally returned to the bottom of the tower for recycling.

Preferably, the height of the biological filter bed is 1.2-1.5m, and the exhaust gas is evenly distributed to the biological filter bed through the bottom gas distribution pipe from bottom to top, with a flow rate of 10-12mm/s and a contact residence time of 100-150s. The top of the biological filter bed is arranged with Sprinklers.

There are 5 sprinklers arranged on the top of the biological filter bed, and the water consumption of each sprinkler is 0.4-0.6m ³ /h, one of which is used for humidification, and the other four are used for green irrigation. 3-5 times, 5-8 minutes each time; 2-3 times a week in spring and autumn, 3-5 minutes each time; not turned on in winter.

Preferably, the dosage of the attapulgite is 50-100mg/L, and the specific surface area of the attapulgite adsorbent is 12-35m ² /g; the Al ₂ O ₃ contained in the attapulgite is 9.0- 10.1 mg/Kg, Fe ₂ O ₃ 5.7-6.7 mg/Kg; CaO 0.42-1.95 mg/Kg.

Preferably, the induced draft fan in step (6) adopts a centrifugal fan to reduce noise.

Beneficial effects: compared with the prior art, the present invention can comprehensively and effectively remove pollutants such as sulfide and zinc ions in the viscose wastewater in the process of stripping reaction, neutralization reaction precipitation and cascaded aeration. Waste gas is fully and effectively removed in the lye spray tower and biological filter bed process. The sludge is fully and effectively removed in the process of sludge thickening and chamber filter press, so that the water quality index after treatment is qualified, and the water quality after treatment meets the requirements of chemical oxygen demand (COD) ≤ 80mg/L, Zn ²⁺ ≤ 2mg /L, S ^2- ≤1mg/L, has the superiority that the existing technology cannot match. In addition, using this technology, the operation is safe and convenient. In terms of economy, because the existing technology is flat, it has high feasibility. Finally, this technology uses the lye spray tower and biological filter bed technology for the first time, and the effect is good. It fills the gap at home and abroad. technology gap.

Description of drawings

Fig. 1 is the method flowchart of concrete implementation of the present invention;

Fig. 2 is a schematic structural view of the biological filter bed of the present invention.

Detailed ways

As shown in Figure 1 and Figure 2, the present invention provides a system for the treatment of viscose fiber wastewater, sludge, and waste gas, including sump A, sump B, aeration blow-off pool, neutralization reaction pool, primary sedimentation tank, pH adjustment tank, aeration tank, secondary settling tank, sludge concentration tank, odor source collection system, air distribution pipeline system and biological filter bed, among which: water collection tank A and water collection tank B are respectively connected with aeration stripping tank connected; the aeration blow-off tank is sequentially connected with the neutralization reaction tank, the primary sedimentation tank, the pH adjustment tank, the aeration tank, the secondary sedimentation tank, and the sludge concentration tank; the odor source collection system is used to collect , neutralize the waste gas from the reaction tank, aeration tank and sludge concentration tank, and the collected waste gas is sent to the packing layer of the lye spray tower and the active soil filter bed in sequence through the induced draft fan. Among them, the induced draft fan adopts a centrifugal fan to reduce noise.

Specifically, an air agitation device is installed inside the aeration blow-off tank, a glass fiber reinforced plastic gas collecting hood is arranged above to collect the waste gas generated during the blow-off process, and a sedimentation device is installed at the bottom to precipitate the hemicellulose and Oily substances, etc., the precipitated sludge enters the sludge thickening tank. The neutralization reaction tank includes a reaction zone and a sedimentation zone. The neutralization reaction sedimentation tank is equipped with a glass fiber reinforced plastic gas collecting hood. Among them, the sedimentation zone adopts a flat flow sedimentation tank type for efficient separation of mud and water. The aeration of the cascade aeration tank adopts the aeration and stirring device of the double-layer impeller. According to the flow of the water body, the water is designed to enter the center of the impeller. The biological filter bed is composed of a gravel support layer, an ecological filter layer and a soil layer arranged in sequence. Plants are planted in the soil layer. Among them, the height of the gravel support layer is 0.2-0.5m, the particle size is 8-16mm; the height of the ecological filter layer is 0.6-0.8 m, particle size 2-4mm; soil layer height 0.2-0.5m, particle size less than 0.01mm. Among them, the plants include rushes (Juncus effusus L.), iris (Iristectorum Maxim.), reeds (Phragmites australias Trin.), the planting ratio is 1:1:1, and the planting density is not less than 16 plants/m ² .

The method that utilizes above-mentioned device to process is:

(1) Collect acidic wastewater and alkaline wastewater: through separate pipelines, respectively collect acidic wastewater and alkaline wastewater, acidic wastewater volume: alkaline wastewater volume ratio (3-5): 1;

(2) Aeration and blow-off: introduce the water obtained in step (1) into the aeration and blow-off tank, the aeration intensity is 10-15m ³ /m ² ·h, the residence time is 0.8-1.0h, and the pH is about 2-3. Use high steam-water ratio for mixing and stirring to increase the reaction speed and effect in the aeration blowing tank. Under acidic conditions, the waste gas in the waste water is blown off, and the waste gas generated during the blow-off process is collected, and the precipitated sludge precipitated by the precipitation acid enters the sludge thickening tank;

(3) neutralization reaction precipitation: the water of step (2) gained is introduced into the neutralization reaction sedimentation tank, and at first dosing purity is 85-88% ferrous sulfate to further reduce the sulfide content in the reaction zone of the neutralization reaction sedimentation tank, Because ferrous sulfate has a strong redox property, the removal rate of sulfide is very high, and its cost is low, and it has a good decolorization effect. On the one hand, the divalent iron ions (Fe ²⁺ ) generated by hydrolysis after ferrous sulfate is added to wastewater will react with sulfur ions (S ²⁻ ) to form iron sulfide (FeS) and precipitate into sludge. On the other hand, after ferrous sulfate is put into the wastewater, the complex produced by its hydrolysis, under the action of hydraulic stirring conditions, will pass the sulfur ions and other pollutant suspended matter in the wastewater through a series of adsorption-electroneutralization -The net capture-polymerization reaction promotes the sulfide to form iron sulfide, and finally aggregates with other organic pollutants to form alum flowers, which precipitate under the action of gravity to form dense sludge. After adding calcium carbide slag with a purity of 11-15% to increase the pH value of the wastewater to 9.5-10.5, the dosage of calcium carbide slag: 0.9-1.2kg/ ^m3 sewage, forming an alkaline precipitate of Zn ²⁺ ; followed by adding polypropylene Amide PAM, the dosage is 3-10mg/L, through charge neutralization, it can reduce the kinetic potential and coagulate, which enhances the flocculation effect of water. The reaction zone improves the coagulation and coagulation effect through aeration, the aeration intensity is 5-7m ³ /m ² ·h, and the residence time is 0.5-1.0h;

The sedimentation area of the neutralization reaction sedimentation tank adopts the type of advection sedimentation tank to efficiently separate mud and water. The floc particles formed are larger and easier to settle, which can achieve a better effect of removing COD and refractory organic matter; surface load 1.0～1.5m ³ /m ² ·h, the sedimented sludge enters the sludge thickening tank, and the waste gas generated during the collection and reaction precipitation process is collected;

(4) Cascade aeration tank

The water obtained in step (3) is introduced into the step aeration process, which is divided into grade I (including regions A and B), grade II (including regions C and D) and grade III (including regions E and F), respectively:

Level I (including areas A and B): dissolved oxygen 0.5-2.0mg/L, residence time 3-6h, and add attapulgite adsorbent, the dosage is 50-100mg/L, the attapulgite adsorbent used The specific surface area of the agent is 12-35m ² /g, which contains Al ₂ O ₃ 9.0-10.1mg/Kg; Fe ₂ O ₃ 5.7-6.7mg/Kg; CaO 0.42-1.95mg/Kg. Add attapulgite adsorbent to adsorb refractory organic matter and provide a carrier for aerobic microorganisms, improve sludge concentration and sedimentation performance, and then improve effluent water quality;

Class II (including areas C and D): dissolved oxygen 3.5-4.5mg/L, residence time 6-8h;

Level III (including areas E and F): Dissolved oxygen 4.6-5.5mg/L, residence time 1-2h; effluent meets the discharge standard for standard discharge.

The aeration of the cascade aeration tank adopts the aeration and stirring device of the double-layer impeller, which combines the fluid characteristics and the mechanical movement to the greatest extent. According to the flow of water body, the water is designed to enter from the center of the impeller. On the one hand, it reduces the turbulence of the water intake, and on the other hand, it ensures that the pressure of the liquid on the surface of the impeller is uniform, so as to ensure the balance of the whole machine in a moving state. Effectively eliminate the dead angle of stirring. The large specific surface area can obtain a large area of water exchange. A glass fiber reinforced plastic gas collecting hood is installed on the cascade aeration tank to collect the exhaust gas during the aeration process.

(5) Sludge treatment:

The sludge from the aeration stripping tank, neutralization reaction sedimentation tank, and cascade aeration tank is discharged into the sludge thickening tank, and after being concentrated, the chamber filter press is used for mechanical dehydration. The supernatant and sewage of the sludge thickening tank The supernatant of the mud dewatering machine is returned to the aeration blowing tank;

(6) Exhaust gas treatment:

The exhaust gas collected from the aeration stripping tank, neutralization reaction sedimentation tank, cascade aeration tank and sludge thickening tank enters the lye spray tower through the induced draft fan, passes through the lye spray tower packing layer, and the waste gas is oxidized with hydrogen The sodium absorption liquid is fully contacted with the gas-liquid two-phase absorption neutralization reaction. After the acid mist exhaust gas is purified, it is dehydrated and defogged by the defogging plate and then discharged into the biological filter bed by the fan. The absorption liquid is pressurized by the water pump at the bottom of the tower. The top of the tower is sprayed down, and finally returned to the bottom of the tower for recycling.

The processing effects of the device of the present invention will be described below through specific examples.

Example 1

In Example 1, the raw water is taken from a viscose wastewater factory, with a total daily treatment capacity of 56,000m ³ /d, of which the amount of acidic wastewater is 42,000m ³ /d, and the amount of alkaline wastewater is 14,000m ³ /d. It runs for 24 hours and treats the sewage every hour The volume is 2333m ³ /h. The main pollution indicators of wastewater are COD _Cr , pH, SS, Zn ²⁺ , S ^2- . The quality of wastewater is as follows:

Put the waste water to be treated into the process construction treatment and reuse system of the present invention, the waste water to be treated sequentially passes through the sump, the aeration stripping tank, the neutralization reaction tank, the primary sedimentation tank, the pH adjustment tank, the aeration tank, the secondary sedimentation tank pool, sludge thickening pool; neutralization reaction pool, adding ferrous sulfate with a purity of 85% and calcium carbide slurry with a purity of 12% to control the pH of the wastewater to 10-10.5; pH adjustment tank to adjust the pH of the wastewater to 7.2 to ensure biochemical The system is under suitable conditions, and N and P nutrients are added to the water distribution well to achieve COD:N:P=100:5:1 to meet the needs of the subsequent biochemical system; for other treatment methods, see the previous treatment methods. The remaining sludge in the secondary settling tank is returned to the aeration tank at a ratio of 25%, and the sludge is discharged into the sludge thickening tank; the sludge return ratio is set according to the process design process and factory experience. The sludge return is mainly to maintain the activity of the sludge. The sludge is not expanded, and the suspended fixed concentration in the tank is kept relatively stable. If the reflux ratio is too high, the activity of the sludge is low and the treatment performance is poor; if the reflux ratio is too low, sludge bulking may occur. The supernatant of the sludge thickening tank flows into the water inlet of the sump, and the turbid liquid enters the sludge dewaterer through the lift pump; the sludge dewaterer is a box-type filter press, which adopts mechanical dehydration, and the filtrate flows into the water inlet of the sump, and the dried sludge Sinotrans.

After a period of operation management, after the system is stable, the treatment effect of the present invention is: the CODCr of the secondary sedimentation tank is lower than 75mg/L, the pH is controlled at about 7, the SS is lower than 60mg/L, and the Zn ²⁺ concentration is lower than 2mg/L. L, S ^2- concentration is lower than 1mg/L; gas chromatography (GC-MS) analysis of the components in different structural units shows that the acidic adjustment pool contains C ₇ H ₈ , C ₄ H ₆ O ₂ , C ₄ H ₆ 18 kinds of organic substances such as O ₃ , including 6 kinds of lipids, 4 kinds of alkanes, 4 kinds of acids, 1 kind of ketones, 2 kinds of benzene derivatives, and 1 kind of amides; the alkaline adjustment pool contains C ₆ H ₈ O, C ₆ H ₁₂ O, C ₇ H ₈ and other 27 organic compounds, including 6 lipids, 3 alkanes, 2 alcohols, 2 acids, 4 ketones, 2 phenols, 2 benzene derivatives, 2 amides, 3 kinds of heterocyclic compounds, 1 kind of olefin derivative; the neutralization reaction pool contains 21 kinds of organic substances such as C ₆ H ₁₂ O, C ₇ H ₈ , C ₆ H ₁₂ O ₂ , among which there are 6 kinds of lipids, 1 kind of alkanes, 2 alcohols, 4 acids, 3 ketones, 1 phenol, 2 benzene derivatives, 1 amide, 1 heterocyclic compound; the primary sedimentation tank contains C ₇ H ₈ , C ₇ H ₈ O, C ₈ H ₁₆ O ₂ and other 29 organic compounds, including 8 lipids, 4 alkanes, 3 alcohols, 3 acids, 2 ketones, 2 phenols, 4 benzene derivatives, 1 amide, 1 hetero Cyclic compound, a kind of acid chloride; area A of the aeration tank contains organic substances such as C ₅ H ₉ Cl, C ₆ H ₈ O, C ₆ H ₁₂ O, and area B contains C ₅ H ₉ Cl, C ₆ H ₈ O, C ₆ Organic substances such as H ₁₂ O, region C contains organic substances such as C ₆ H ₈ O, C ₆ H ₁₂ O, C ₇ H ₈ , and region D contains C ₇ H ₈ , C ₄ H ₆ O ₃ , C ₅ H ₈ O ₃ , etc. Organic matter, area E contains organic matter such as C ₇ H ₈ , C ₄ H ₆ O ₃ , C ₅ H ₈ O ₃ , area F contains organic matter such as C ₅ H ₉ Cl, C ₇ H ₈ , C ₆ H ₁₄ O, etc., the entire exposure A total of 29 kinds of organic compounds in the gas unit, including 6 kinds of lipids, 4 kinds of alkanes, 3 kinds of alcohols, 4 kinds of acids, 2 kinds of ketones, 1 kind of phenols, 1 kind of ethers, 2 kinds of benzene derivatives, 2 kinds of amides, and 1 kind of Heterocyclic compounds, 3 kinds of olefin derivatives; the outlet contains 24 kinds of organic compounds such as C ₆ H ₈ O, C ₆ H ₁₂ O, C ₇ H ₈ , among which there are 6 kinds of lipids, 3 kinds of alcohols, 2 kinds of acids, and 3 kinds of Ketones, 1 phenol, 3 ethers, 1 benzene derivative, 2 amides, 3 heterocyclic compounds. Therefore, it can be found that there are many types of organic matter in the acidic adjustment pool and the alkaline adjustment pool, and the components are relatively complex. After the neutralization reaction tank, the types of organic matter in the wastewater are significantly reduced, mainly benzene derivatives, phenols, and alkanes. After the primary sedimentation tank and aeration tank, the concentration of organic pollutants is less. No alkanes were found in the organic matter in the final discharge port, indicating that the biochemical treatment effect is good. In addition, under the premise of not affecting the product quality, this method greatly improves the reuse rate of reclaimed water to more than 60%, and the average treatment cost per ton of water is 0.65 yuan (excluding depreciation, maintenance and sludge disposal fees, etc.) .

Example 2

In Example 2, the raw water is taken from a viscose wastewater factory wastewater, with a total daily treatment capacity of 48,000m ³ /d, of which the amount of acidic wastewater is 32,000m ³ /d, and the amount of alkaline wastewater is 16,000m ³ /d. It runs for 24 hours and treats sewage every hour The volume is 2100m ³ /h. The main pollution indicators of wastewater are COD _Cr , pH, SS, Zn ²⁺ , S ^2- . The quality of wastewater is as follows:

Put the waste water to be treated into the process construction treatment and reuse system of the present invention, the waste water to be treated sequentially passes through the sump, the aeration stripping tank, the neutralization reaction tank, the primary sedimentation tank, the pH adjustment tank, the aeration tank, the secondary sedimentation tank pool, sludge concentration pool; neutralization reaction pool, adding ferrous sulfate with a purity of 86% and calcium carbide slurry with a purity of 13% to control the pH of the wastewater to 10-10.5; pH adjustment tank to adjust the pH of the wastewater to 7.5 to ensure biochemical The system is under suitable conditions, and N and P nutrients are added to the water distribution well to achieve COD:N:P=100:5:1 to meet the needs of the subsequent biochemical system; other conditions are described above, and the remaining sludge in the secondary settling tank is 30% of the proportion is returned to the aeration tank, and the sludge is discharged into the sludge thickening tank; the supernatant of the sludge thickening tank flows into the water inlet of the sump, and the turbid liquid enters the sludge dewatering machine through the lifting pump; the sludge dewatering machine is a van type The filter press adopts mechanical dehydration, the press filtrate flows into the water inlet of the sump, and the dry mud is transported outside.

After a period of operation management, after the system is stable, the treatment effect of the present invention is: the CODCr of the secondary sedimentation tank is lower than 80mg/L, the pH is controlled at about 7, the SS is lower than 70mg/L, and the Zn ²⁺ concentration is lower than 2mg/L. L, S ^2- concentration is lower than 1mg/L; gas chromatography (GC-MS) analysis of components in different structural units shows that the acidic adjustment pool contains C ₅ H ₈ O ₃ , C ₄ H ₆ O ₂ , C ₁₈ 15 kinds of organic substances such as H ₃₄ O ₂ , including 5 kinds of lipids, 3 kinds of alkanes, 4 kinds of acids, 1 kind of ketones, 1 kind of benzene derivatives, and 1 kind of amides; the alkaline adjustment pool contains C ₆ H ₁₂ O ₂ , C ₆ H ₁₂ O, C ₁₄ H ₂₂ O and other 25 kinds of organic substances, including 5 kinds of lipids, 3 kinds of alkanes, 2 kinds of alcohols, 2 kinds of acids, 3 kinds of ketones, 2 kinds of phenols, 2 kinds of benzene derivatives, 2 kinds of amides, 3 kinds of heterocyclic compounds, 1 kind of olefin derivatives; the neutralization reaction pool contains 20 kinds of organic substances such as C ₆ H ₁₂ O, C ₅ H ₈ O ₃ , C ₁₆ H ₂₂ O ₄ , among which 6 kinds Lipid, 1 alkane, 2 alcohols, 4 acids, 2 ketones, 1 phenol, 2 benzene derivatives, 1 amide, 1 heterocyclic compound; the primary sedimentation tank contains C5H8O3, C12H20O, C18H36O2, etc. 25 organic compounds, including 6 lipids, 3 alkanes, 3 alcohols, 3 acids, 2 ketones, 2 phenols, 1 benzene derivative, 1 amide, 1 heterocyclic compound, and acyl chloride ; Area A of the aeration tank contains organic matter such as C ₇ H ₈ , C ₅ H ₈ O ₃ , and C ₆ H ₁₂ O, and area B contains organic matter such as C ₇ H ₈ , C ₆ H ₁₂ O ₂ , and C ₆ H ₁₂ O. Region C contains organic substances such as C ₆ H ₁₂ O ₂ , C ₆ H ₁₂ O, and C ₇ H ₈ , and region D contains organic substances such as C ₇ H ₈ , C ₇ H ₁₄ O ₃ , C ₁₆ H ₃₂ O ₂ , and region E contains C ₇ H ₈ , C ₇ H ₁₄ O ₃ , C ₅ H ₈ O ₃ and other organic matter, area F contains organic matter such as C ₇ H ₁₄ O ₃ , C ₇ H ₈ , C ₆ H ₈ OS, etc. The entire aeration unit has a total of 30 organic compounds, including 6 lipids, 4 alkanes, 3 alcohols, 4 acids, 3 ketones, 1 phenol, 1 ether, 2 benzene derivatives, 2 amides, 1 heterocyclic compound, 3 kinds of olefin derivatives; the outlet contains 22 kinds of organic substances such as C ₅ H ₈ O ₃ , C ₆ H ₁₂ O, C ₁₂ H ₂₆ O ₄ , among which there are 5 kinds of lipids, 3 kinds of alcohols, 2 kinds of acids, and 2 kinds of ketones , 1 phenol, 3 ethers, 1 benzene derivative, 2 amides, 3 heterocyclic compounds. Therefore, it can be found that there are many types of organic matter in the acidic adjustment pool and the alkaline adjustment pool, and the components are relatively complex. After the neutralization reaction tank, the types of organic matter in the wastewater are significantly reduced, mainly benzene derivatives, phenols, and alkanes. After the primary sedimentation tank and aeration tank, the concentration of organic pollutants is less. No alkanes were found in the organic matter in the final discharge port, indicating that the biochemical treatment effect is better. In addition, under the premise of not affecting the product quality, this method greatly improves the reuse rate of reclaimed water to more than 60%, and the average treatment cost per ton of water is 0.60 yuan (excluding depreciation, maintenance and sludge disposal fees, etc.) .

The invention completely and effectively removes pollutants such as sulfide and zinc ions in the viscose fiber wastewater in the processes of stripping reaction, neutralization reaction precipitation and cascade aeration. Waste gas is fully and effectively removed in the lye spray tower and biological filter bed process. The sludge is fully and effectively removed in the process of sludge thickening and chamber filter press, so that the water quality index after treatment is qualified, and the water quality after treatment meets the requirements of chemical oxygen demand (COD) ≤ 80mg/L, Zn ²⁺ ≤ 2mg /L, S ^2- ≤1mg/L, has the superiority that the existing technology cannot match. In addition, using this technology, the operation is safe and convenient. In terms of economy, because the existing technology is flat, it has high feasibility. Finally, this technology uses the lye spray tower and biological filter bed technology for the first time, and the effect is good. It fills the gap at home and abroad. technology gap.

The above schematically describes the present invention and its implementation, which is not restrictive, and what is shown in the drawings is only one of the implementations of the present invention, and the actual structure is not limited thereto. Therefore, if a person of ordinary skill in the art is inspired by it, without departing from the inventive concept of the present invention, without creatively designing a structural mode and embodiment similar to the technical solution, it shall all belong to the protection scope of the present invention .

Claims (10)

1. A system for viscose fiber waste water, sludge, waste gas treatment, is characterized in that, comprises sump A, sump B, aeration stripping tank, neutralization reaction tank, primary settling tank, pH adjustment tank, aeration tank Air tank, secondary settling tank, sludge thickening tank, odor source collection system, lye spray tower packing layer and biological filter bed, of which: The sump A and the sump B are respectively connected with the aeration and stripping tanks, The aeration blow-off tank is sequentially connected with a neutralization reaction tank, a primary sedimentation tank, a pH adjustment tank, an aeration tank, a secondary sedimentation tank, and a sludge concentration tank; The odor source collection system is used to collect the waste gas from the aeration stripping tank, the neutralization reaction tank, the aeration tank and the sludge thickening tank, and the collected waste gas is sent to the packing layer of the lye spray tower and the Active soil filter bed. 2. The system according to claim 1, wherein an air agitation device is provided inside the aeration blow-off tank, and a glass fiber reinforced plastic gas collection hood is arranged above to collect the waste gas generated during the blow-off process, and the bottom is provided There is a settling device, and the settled sludge enters the sludge thickening tank. 3. The system according to claim 1, wherein the neutralization reaction tank comprises a reaction zone and a settling zone, and a glass fiber reinforced plastic gas collection hood is arranged on the neutralization reaction settling tank, wherein the settling zone adopts an advection settling tank pond type for efficient separation of mud and water. 4. The system according to claim 1, characterized in that the aeration of the cascade aeration tank adopts the aeration and stirring device of the double-layer impeller, and according to the flow of the water body, it is designed to enter water from the center of the impeller, and the cascade aeration tank is equipped with glass fiber reinforced plastics Gas hood. 5. The system according to claim 1, wherein the biological filter bed is composed of a gravel supporting layer, an ecological filter layer and a soil layer arranged in sequence, and the soil layer is planted with plants, wherein the height of the gravel supporting layer is 0.2 -0.5m, particle size 8-16mm; ecological filter layer height 0.6-0.8m, particle size 2-4mm; soil layer height 0.2-0.5m, particle size less than 0.01mm. 6. The system according to claim 5, wherein five sprinklers are arranged on the top of the biological filter bed, and the water consumption of each sprinkler is 0.4-0.6m ³ /h, one of which is used for humidification, The other four are used for green irrigation; the plants include rushes, iris and reeds, the planting ratio is 1:1:1, and the planting density is not less than 16 plants/m ² . 7. a method for viscose fiber waste water, sludge, waste gas treatment, is characterized in that, comprises the steps: (1) Collect acidic wastewater and alkaline wastewater: through separate pipelines, respectively collect acidic wastewater and alkaline wastewater, acidic wastewater volume: alkaline wastewater volume ratio (3-5): 1; (2) Aeration and blow-off: introduce the water obtained in step (1) into the aeration and blow-off tank, the aeration intensity is 10-15m ³ /m ² ·h, the residence time is 0.8-1.0h, and the pH is about 2-3. Under acidic conditions, the waste gas in the waste water is blown off, and the waste gas generated during the blow-off process is collected, and the precipitated sludge precipitated by the precipitation acid enters the sludge thickening tank; (3) Neutralization reaction precipitation: the water of step (2) gained is introduced into the neutralization reaction sedimentation tank, and in the reaction zone of the neutralization reaction sedimentation tank, at first adding ferrous sulfate with a purity of 85-88% further reduces the sulfide content , after adding calcium carbide slag with a purity of 11-15% to increase the pH value of the wastewater to 9.5-10.5, the dosage of calcium carbide slag: 0.9-1.2kg/m ³ sewage, forming an alkaline precipitate of Zn ²⁺ ; Acrylamide PAM, the dosage is 3-10mg/L; the reaction zone improves the coagulation and coagulation effect through aeration, the aeration intensity is 5-7m ³ /m ² ·h, and the residence time is 0.5-1.0h; The sedimentation area of the neutralization reaction sedimentation tank adopts the type of advection sedimentation tank to efficiently separate mud and water. The floc particles formed are larger and easier to settle, which can achieve a better effect of removing COD and refractory organic matter; surface load 1.0～1.5m ³ /m ² ·h, the sedimented sludge enters the sludge thickening tank, and the waste gas generated during the collection and reaction precipitation process is collected; (4) Step aeration: The water obtained in step (3) is introduced into the step aeration process, which is divided into grade I, grade II and grade III, respectively: Level Ⅰ: Dissolved oxygen 0.5-2.0mg/L, residence time 3-6h, and add attapulgite adsorbent; Grade II: dissolved oxygen 3.5-4.5mg/L, residence time 6-8h; Level III: Dissolved oxygen 4.6-5.5mg/L, residence time 1-2h; effluent meets the discharge standard for standard discharge; (5) Sludge treatment: The sludge from the aeration stripping tank, neutralization reaction sedimentation tank, and cascade aeration tank is discharged into the sludge thickening tank, and after being concentrated, the chamber filter press is used for mechanical dehydration. The supernatant and sewage of the sludge thickening tank The supernatant of the mud dewatering machine is returned to the aeration blowing tank; (6) Exhaust gas treatment: The exhaust gas collected from the aeration stripping tank, neutralization reaction sedimentation tank, cascade aeration tank and sludge thickening tank enters the lye spray tower through the induced draft fan, passes through the lye spray tower packing layer, and the waste gas is oxidized with hydrogen The sodium absorption liquid is fully contacted with the gas-liquid two-phase absorption neutralization reaction. After the acid mist exhaust gas is purified, it is dehydrated and defogged by the defogging plate and then discharged into the biological filter bed by the fan. The absorption liquid is pressurized by the water pump at the bottom of the tower. The top of the tower is sprayed down, and finally returned to the bottom of the tower for recycling. 8. The method according to claim 7, characterized in that, the height of the biological filter bed is 1.2-1.5m, and the exhaust gas is evenly distributed to the biological filter bed through the bottom air distribution pipe from bottom to top, at a flow rate of 10-12mm/s, contacting The residence time is 100-150s, and sprinklers are arranged on the top of the biological filter bed. 9. The method according to claim 8, characterized in that 5 sprinklers are arranged on the top of the biological filter bed, and the water consumption of each sprinkler is 0.4-0.6m ³ /h, one of which is used for humidification, The other four are used for green irrigation. For green irrigation, the average summer is 3-5 times a day, 5-8 minutes each time; spring and autumn 2-3 times a week, 3-5 minutes each time; winter is not turned on. 10. The method according to claim 1, characterized in that the dosage of the attapulgite is 50-100 mg/L, and the specific surface area of the attapulgite adsorbent is 12-35 m ² /g; Al ₂ O ₃ contained in attapulgite is 9.0-10.1 mg/Kg, Fe ₂ O ₃ 5.7-6.7 mg/Kg; CaO 0.42-1.95 mg/Kg.