CN111592137A - Zero-discharge treatment process and system for printing and dyeing wastewater - Google Patents

Zero-discharge treatment process and system for printing and dyeing wastewater Download PDF

Info

Publication number
CN111592137A
CN111592137A CN202010301534.3A CN202010301534A CN111592137A CN 111592137 A CN111592137 A CN 111592137A CN 202010301534 A CN202010301534 A CN 202010301534A CN 111592137 A CN111592137 A CN 111592137A
Authority
CN
China
Prior art keywords
ceramic membrane
membrane filter
tubular ceramic
wastewater
printing
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
CN202010301534.3A
Other languages
Chinese (zh)
Inventor
郭丹
张丽云
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nanjing Xiaoxiang Engineering Technology Co ltd
Original Assignee
Nanjing Xiaoxiang Engineering Technology Co ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Nanjing Xiaoxiang Engineering Technology Co ltd filed Critical Nanjing Xiaoxiang Engineering Technology Co ltd
Priority to CN202010301534.3A priority Critical patent/CN111592137A/en
Publication of CN111592137A publication Critical patent/CN111592137A/en
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F9/00—Multistage treatment of water, waste water or sewage
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/001—Processes for the treatment of water whereby the filtration technique is of importance
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/48—Treatment of water, waste water, or sewage with magnetic or electric fields
    • C02F1/488—Treatment of water, waste water, or sewage with magnetic or electric fields for separation of magnetic materials, e.g. magnetic flocculation
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
    • C02F1/5236—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using inorganic agents
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
    • C02F1/5281—Installations for water purification using chemical agents
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/66—Treatment of water, waste water, or sewage by neutralisation; pH adjustment
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/72—Treatment of water, waste water, or sewage by oxidation
    • C02F1/78—Treatment of water, waste water, or sewage by oxidation with ozone
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F2001/007—Processes including a sedimentation step
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
    • C02F2103/30—Nature of the water, waste water, sewage or sludge to be treated from the textile industry
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2209/00—Controlling or monitoring parameters in water treatment
    • C02F2209/06—Controlling or monitoring parameters in water treatment pH
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2209/00—Controlling or monitoring parameters in water treatment
    • C02F2209/08—Chemical Oxygen Demand [COD]; Biological Oxygen Demand [BOD]
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2209/00—Controlling or monitoring parameters in water treatment
    • C02F2209/10—Solids, e.g. total solids [TS], total suspended solids [TSS] or volatile solids [VS]
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2301/00—General aspects of water treatment
    • C02F2301/08—Multistage treatments, e.g. repetition of the same process step under different conditions

Landscapes

  • Life Sciences & Earth Sciences (AREA)
  • Hydrology & Water Resources (AREA)
  • Engineering & Computer Science (AREA)
  • Environmental & Geological Engineering (AREA)
  • Water Supply & Treatment (AREA)
  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)

Abstract

The invention relates to a zero-discharge treatment process and a zero-discharge treatment system for printing and dyeing wastewater, and belongs to the technical field of water treatment. The desizing wastewater of polyacrylate slurry can be treated, most of available slurry in the desizing wastewater is recovered, the rest wastewater is treated in multiple steps, sulfate in the waste wastewater is recovered, and calcium sulfate precipitate is obtained and used for building materials; meanwhile, through the steps of coagulation, membrane filtration, ozone oxidation and nanofiltration, the COD in the wastewater is remarkably reduced, and the produced water can be recycled.

Description

Zero-discharge treatment process and system for printing and dyeing wastewater
Technical Field
The invention relates to a zero-discharge treatment process and a zero-discharge treatment system for printing and dyeing wastewater, and belongs to the technical field of water treatment.
Background
The waste water from cotton textile industry comes from dyeing and finishing section, including desizing, boiling, bleaching, mercerizing, dyeing, printing and finishing. And the waste water discharge of the weaving workshop section is less.
The continuous spinning process is an important technical progress in the production mode of viscose fibers, the sizing is an important link of the production process, and the quality of sizing has important influence on indexes such as fiber broken filaments, wear resistance, reinforcement, elongation reduction and the like. The method aims to achieve high efficiency and low cost by selecting and matching the sizing agent according to the variety and the count of the fiber, so that the sizing agent has the advantages of less broken filaments, good wear resistance, increased strength and stable extension after the fiber is sized, and is the key for sizing agent application. The fiber broken filaments are related to the spinning process, the process parameters of each procedure and the equipment state of each procedure. Particularly in the process of winding and forming the tows, the cohesion among the fibers can be damaged by friction, and new broken filaments are generated. One of the main objectives of continuous spin sizing is to reduce the tow fuzz.
Desizing wastewater generally accounts for about 15% of the total amount of wastewater, and pollutants account for about half of the total amount. The desizing wastewater is alkaline organic wastewater, contains various pulp decomposers, fiber scraps, acid, enzyme and other pollutants, and is light yellow. The slurries mainly used at present include: 1. starch-based slurry; 2. PVA slurry; 3. a carboxymethyl cellulose pulp; 4. polyacrylate size.
The waste water formed in the desizing process of the polyacrylate size contains a large amount of polyacrylate, alkali, an auxiliary agent and the like, so that the polyacrylate size has high COD, is extremely difficult to biodegrade and has high treatment difficulty; in addition, because the wastewater needs to be neutralized, a large amount of sulfuric acid needs to be added, and in the process of coagulating and decoloring the wastewater, ferrous sulfate is usually used as a coagulant, but the ferrous sulfate is added in a high amount and is easy to hydrolyze, so that a large amount of sulfate is generated, and the sulfate content in the wastewater is high.
Disclosure of Invention
The purpose of the invention is: solves the problems of difficult biodegradation of the sizing agent and high sulfate content when the wastewater generated in the desizing treatment process of the polyacrylate sizing agent in the prior art is treated. Provides a zero-emission treatment process of polyacrylate desizing wastewater.
The technical scheme is as follows:
a zero-emission treatment process for printing and dyeing wastewater comprises the following steps:
step 1, feeding printing and dyeing wastewater into a first tubular ceramic membrane filter for filtering, and concentrating slurry;
step 2, adjusting the pH of the filtrate obtained by the first tubular ceramic membrane filter, and adding a coagulant for coagulation;
step 3, filtering the wastewater obtained in the step 2 by adopting a second tubular ceramic membrane filter to remove alum flocs;
step 4, adding lime into the filtrate obtained in the step 3 to precipitate sulfate ions;
step 5, filtering the wastewater obtained in the step 4 by adopting a third tubular ceramic membrane filter to remove precipitates;
step 6, carrying out ozone oxidation treatment on the filtrate obtained in the step 5;
and 7, filtering the wastewater obtained in the step 6 by adopting a nanofiltration membrane.
Preferably, the printing and dyeing wastewater is desizing wastewater with polyacrylate as a sizing agent.
Preferably, the water quality of the desizing wastewater is: COD5000-30000mg/L, BOD 200 + 500mg/L, SS 30-90mg/L, pH9-13, light yellow.
Preferably, in step 1, the heat in the printing and dyeing wastewater is obtained through an evaporator, and is transferred to the wastewater entering the third tubular ceramic membrane filter for filtering in step 5 through a heat pump system.
Preferably, the first tubular ceramic membrane filter has an average pore size in the range of 8 to 20nm and a cross-flow velocity during filtration of 1 to 5 m/s.
Preferably, in step 1, dialysis with water is also required during concentration.
Preferably, the pH adjustment in step 2 is performed using a mixed acid of sulfuric acid and hydrochloric acid, and the pH is adjusted to 8.0 to 9.0.
Preferably, the coagulant is ferrous sulfate, and the addition amount of the coagulant is 0.5-2 g/L; and the coagulant aid polyacrylamide can be added while coagulating, and the adding amount is 20-40 mg/L.
Preferably, the average pore size of the second tubular ceramic membrane filter 7 in step 3 is in the range of 200-800nm, and the cross-flow velocity during filtration is 2-5 m/s.
Preferably, the amount of lime added in step 4 is converted from the stoichiometric amount of sulfate ions in the completely precipitated wastewater.
Preferably, the third tubular ceramic membrane filter has an average pore size in the range of 50 to 200nm and a cross-flow velocity during filtration of 1 to 5 m/s.
Preferably, the concentrated solution containing calcium sulfate obtained by the third tubular ceramic membrane filter is used as a building material after calcium sulfate is recovered by plate-and-frame filtration.
Preferably, when lime is added, magnetic particles are also added, and the adding amount is 0.2-0.5 wt%; and detecting the magnetic conductivity in the pipeline in real time at a feed liquid outlet at the interception side of the third tubular ceramic membrane filter through a magnetic conductivity detector, and stopping the third tubular ceramic membrane filter when the magnetic conductivity is lower than a threshold value, and cleaning a filter channel.
Preferably, the magnetic particles are also recovered magnetically by an online magnetic separator on the downstream side of the magnetic permeability detector, and the recovered magnetic particles are dosed to the precipitation reaction in step 4.
Preferably, the magnetic particles are nitric acid modified Fe3O4Magnetic particles, the particle size range is 200-500 nm.
Preferably, the amount of the added ozone can be 100-300ppm, the temperature of the ozone reaction can be 40-50 ℃, and the reaction time is 30-60 min.
Preferably, a ceramic nanofiltration membrane is used in the step 7, and the molecular weight cut-off is 200-400 Da.
A zero discharge system of printing and dyeing wastewater comprises:
the desizing waste liquid tank is used for storing desizing waste water;
the first tubular ceramic membrane filter is connected to the desizing waste liquid tank and is used for carrying out slurry concentration treatment on the desizing waste water;
the water filling port is connected with the feed port of the first tubular ceramic membrane filter and is used for performing water filling dialysis treatment on the dialysate of the first tubular ceramic membrane filter;
the coagulation tank is connected to the permeation side of the first tubular ceramic membrane filter and is used for carrying out coagulation treatment on the permeation liquid obtained by the first tubular ceramic membrane filter;
the acid adding port is connected with the coagulation tank and is used for adjusting the pH of the penetrating fluid obtained by the first tubular ceramic membrane filter;
the coagulant adding port is connected with the coagulation tank and used for adding a coagulant into the coagulation tank;
the second tubular ceramic membrane filter is connected with the coagulation tank and is used for filtering the wastewater after coagulation reaction to remove a concrete body;
the precipitation reaction tank is connected to the permeation side of the second tubular ceramic membrane filter and is used for carrying out precipitation reaction on sulfate ions of the penetrating fluid obtained by the second tubular ceramic membrane filter;
the lime adding port is connected with the precipitation reaction tank and is used for adding lime into the precipitation reaction tank;
the third tubular ceramic membrane filter is connected with the precipitation reaction tank and is used for filtering the wastewater after the precipitation reaction to remove the precipitate;
the second plate-and-frame filter press is connected to the interception side of the third tubular ceramic membrane filter and is used for carrying out solid-liquid separation on the obtained concentrated solution;
the ozone reaction tank is connected to the permeation side of the third tubular ceramic membrane filter and is used for carrying out ozone oxidation treatment on the penetrating fluid of the third tubular ceramic membrane filter;
and the ceramic nanofiltration membrane is connected with the ozone reaction tank and is used for performing nanofiltration separation treatment on the wastewater treated in the ozone reaction tank.
Preferably, the interception side of the second tubular ceramic membrane filter is connected with a first plate-and-frame filter press for performing solid-liquid separation on the concentrated solution.
Preferably, an evaporator is arranged in the desizing waste liquid tank, a condenser is arranged in the precipitation reaction tank, a compressor and an expansion valve are further included, and the evaporator, the compressor, the condenser and the expansion valve are sequentially connected to form a closed cycle.
Preferably, the device also comprises a magnetic particle adding port for adding magnetic Fe into the precipitation reaction tank3O4And (3) granules.
Preferably, a magnetic permeability detector is further arranged on the outlet pipeline on the interception side of the third tubular ceramic membrane filter and used for detecting the magnetic permeability of the outlet pipeline in real time; an on-line magnetic separator is arranged at the downstream of the magnetic conductivity detector and is used for magnetically separating magnetic Fe3O4Recovering the particles; magnetic permeability detectorIs connected with the magnetic particle adding port.
Advantageous effects
The invention provides an integrated process for treating printing and dyeing wastewater, which can treat desizing wastewater of polyacrylate slurry to recover most of available slurry, then treat the rest wastewater in multiple steps, recover sulfate in the waste wastewater to obtain calcium sulfate precipitate for building materials; meanwhile, through the steps of coagulation, membrane filtration, ozone oxidation and nanofiltration, the COD in the wastewater is remarkably reduced, and the produced water can be recycled.
Drawings
FIG. 1 is a system diagram of the present invention.
FIG. 2 is a graph showing the flux decay of a tubular ceramic membrane during the filtration of precipitated wastewater.
FIG. 3 is an SEM photograph of a filter cake obtained by cross-flow filtration of the precipitate in example 3.
FIG. 4 is an SEM photograph of a filter cake obtained by cross-flow filtration of the precipitate in example 4.
Wherein, 1, a desizing waste liquid groove; 2. a first tubular ceramic membrane filter; 3. a water filling port; 4. a coagulating tank; 5. adding an acid port; 6. a coagulant addition port; 7. a second tubular ceramic membrane filter; 8. a first plate-and-frame filter press; 9. a precipitation reaction tank; 10. adding magnetic particle openings; 11. adding a lime port; 12. a third tubular ceramic membrane filter; 13. a second plate-and-frame filter press; 14. an ozone reaction tank; 15. a ceramic nanofiltration membrane; 16. an evaporator; 17. a compressor; 18. a condenser; 19. an expansion valve; 20. a magnetic permeability detector; 21. an on-line magnetic separator.
Detailed Description
The wastewater to be treated by the invention is desizing wastewater of polyacrylate slurry, and the basic water quality condition is as follows: COD5000-30000mg/L, BOD 200 + 500mg/L, SS 30-90mg/L, pH9-13, light yellow.
In the invention, the wastewater is concentrated by adopting the first tubular ceramic membrane filter, so that polyacrylate slurry in the wastewater can be intercepted, the COD (chemical oxygen demand) in the wastewater is greatly reduced, the recovered polyacrylate can be recycled, and the average pore diameter of the first tubular ceramic membrane filter 2 is 8-20 nm. In the concentration process, it is preferable to carry out dialysis treatment by adding water in order to make some impurity components and alkali in the slurry concentrate be carried out to the permeate side, thereby ensuring the purity of the slurry obtained by concentration to be suitable for reuse.
The obtained ceramic membrane permeate contains organic substances, alkali, and the like. Firstly, acid is added to adjust the pH value to be about alkalescent (the pH value meets the optimal coagulation condition of ferrous sulfate), then a coagulant is added to carry out coagulation treatment, and when the ferrous sulfate coagulant is adopted, a part of impurities such as organic matters in penetrating fluid can be separated to generate alum floc. The filtration removal is carried out by the second tubular ceramic membrane filter 7, and the average pore diameter of the second tubular ceramic membrane filter 7 is in the range of 200-800 nm.
For the second tubular ceramic membrane filter 7, additional lime is added to precipitate calcium sulfate. So that sulfate ions introduced in the coagulation process are converted into calcium sulfate; after filtration through the third tubular ceramic membrane filter 12, calcium sulfate is separated and can be applied to building materials, and the average pore size of the third tubular ceramic membrane filter 12 is in the range of 50-200 nm.
Most of polymers affecting COD and sulfate ions are removed from the filtrate obtained by the third tubular ceramic membrane filter, and the filtrate is subjected to ozone oxidation treatment, wherein the addition amount of ozone can be 100-300ppm, the temperature of the ozone reaction can be 40-50 ℃, and the reaction time is 30-60 min; the COD can be further reduced, the load is reduced for the subsequent deep purification of the nanofiltration membrane, and a small amount of organic matters and divalent and trivalent iron ions in the wastewater can be intercepted through the treatment of the nanofiltration membrane, so that the treated water meeting the discharge standard is obtained.
Because the temperature of the waste water is higher in the desizing process, generally about 90 ℃, in order to reutilize the heat of the waste water, an evaporator 16 is added into the desizing waste water, a condenser is added into a precipitation reaction tank 9, and the evaporator 16, the compressor 17, the condenser 18 and the expansion valve are sequentially connected through an external compressor 17 and an external expansion valve 19 to form a closed cycle; and the heat pump working medium is filled in the closed circulating pipeline, so that a heat pump system is formed, heat in the desizing wastewater is transferred to the precipitation reaction tank 9 through circulating work, and the wastewater after precipitation reaction in the precipitation reaction tank 9 needs to be filtered by a ceramic membrane, so that the temperature of the precipitated wastewater is increased, the flux of water in membrane pores can be remarkably increased due to the reduction of the viscosity of the water in the filtering process of the ceramic membrane, and the operation flux of the third tubular ceramic membrane filter 12 is remarkably increased.
In an improved embodiment, when the precipitation reaction step is carried out, the generated calcium sulfate precipitation particles are small, so that the pore channels of the ceramic membrane filter are easy to block and pollute, and the flux recovery is difficult; meanwhile, because the surface of the calcium sulfate is electronegative, Fe with the surface modified by nitric acid is added into the lime while the lime is added3O4The magnetic particles have positive surface charge, and generated precipitates can be adsorbed on the surfaces of the magnetic particles through electrostatic action during precipitation reaction to form larger precipitation nuclei, so that membrane pores of a ceramic membrane are prevented from being blocked and polluted in the precipitation and filtration process; the magnetic particles may be added in an amount of 0.2-0.5 wt%.
In addition, when the adopted tubular ceramic membrane filters the sediment, more filter cakes can be accumulated in the channel, and although the filter cakes can be flushed out of the channel in the cross-flow filtering process to avoid excessive deposition of the filter cakes, the filter cakes in the channel can still completely block the channel under extreme conditions, so that the cross-flow filtering cannot be carried out. Therefore, the magnetic permeability detector is arranged at the outlet end of the channel of the tubular ceramic membrane filter, the magnetic permeability in the tubular ceramic membrane filter can be detected in real time, since the amount of the magnetic particles added is normally constant, the concentration of the magnetic particles at the cross-flow outlet of the third tubular ceramic membrane filter 12 is constant, and the magnetic permeability of the magnetic particles is in direct proportion to the amount of the particles, the magnetic permeability detected by the magnetic permeability detector 20 is a constant value, in case of potential particle accumulation inside the pipeline, the amount of magnetic particles in the feed liquid discharged from the outlet will decrease, so that, when the magnetic permeability detected by the magnetic permeability detector 20 is smaller than the set value, it can be considered that silting may occur inside the pipe, and at this time, the operation needs to be stopped, and the tubular ceramic membrane element is cleaned to remove the clogging of the pipe with the internal filter cake. The detection of the magnetic permeability of a liquid containing magnetic material in a pipe can be carried out according to prior art solutions, for example, see the relevant technical literature (the sea of the country. ferromagnetic abrasive flow meter design based on the electromagnetic principle [ J ]. automated meters 2015, 36(3): 90-93.). In addition, an online magnetic separator 21 is arranged at the downstream of the magnetic permeability detector 20, and redundant magnetic particles are recovered again in a magnetic manner; the recovered magnetic particles can be cleaned again and recycled, and then are added into the precipitation process through the magnetic particle adding port.
Based on the above method, the system provided by the invention comprises:
a desizing waste liquid tank 1 for storing desizing waste water;
the first tubular ceramic membrane filter 2 is connected to the desizing waste liquid tank 1 and is used for carrying out slurry concentration treatment on the desizing waste water;
the water filling port 3 is connected with the feeding port of the first tubular ceramic membrane filter 2 and is used for performing water filling dialysis treatment on the dialysate of the first tubular ceramic membrane filter 2;
the coagulation tank 4 is connected to the permeation side of the first tubular ceramic membrane filter 2 and is used for carrying out coagulation treatment on the penetrating fluid obtained by the first tubular ceramic membrane filter 2;
the acid adding port 5 is connected with the coagulation tank 4 and is used for adjusting the pH of the penetrating fluid obtained by the first tubular ceramic membrane filter 2;
a coagulant addition port 6 connected to the coagulation tank 4 for adding a coagulant into the coagulation tank 4;
the second tubular ceramic membrane filter 7 is connected to the coagulation tank 4 and is used for filtering the wastewater after coagulation reaction to remove a coagulation body;
a precipitation reaction tank 9 connected to the permeation side of the second tubular ceramic membrane filter 7 and used for carrying out a sulfate ion precipitation reaction on the penetrating fluid obtained by the second tubular ceramic membrane filter 7;
a lime adding port 11 connected to the precipitation reaction tank 9 for adding lime into the precipitation reaction tank 9;
the third tubular ceramic membrane filter 12 is connected to the precipitation reaction tank 9 and is used for filtering the wastewater after the precipitation reaction to remove the precipitate;
the second plate-and-frame filter press 13 is connected to the interception side of the third tubular ceramic membrane filter 12 and is used for performing solid-liquid separation on the obtained concentrated solution;
an ozone reaction tank 14 connected to the permeate side of the third tubular ceramic membrane filter 12 for performing ozone oxidation treatment on the permeate of the third tubular ceramic membrane filter 12;
and the ceramic nanofiltration membrane 15 is connected to the ozone reaction tank 14 and is used for performing nanofiltration separation treatment on the wastewater treated in the ozone reaction tank 14.
Preferably, the interception side of the second tubular ceramic membrane filter 7 is connected with a first plate-and-frame filter press 8 for solid-liquid separation of the concentrated solution.
Preferably, an evaporator 16 is provided in the desizing waste liquid tank 1, a condenser 18 is provided in the precipitation reaction tank 9, a compressor 17 and an expansion valve 19 are further included, and the evaporator 16, the compressor 17, the condenser 18 and the expansion valve are connected in sequence to form a closed cycle.
Preferably, a magnetic particle adding port 10 is further included for adding magnetic Fe into the precipitation reaction tank 93O4And (3) granules.
Preferably, a magnetic permeability detector 20 is further arranged on the outlet pipeline at the interception side of the third tubular ceramic membrane filter 12, and is used for detecting the magnetic permeability of the outlet pipeline in real time; an on-line magnetic separator 21 is also provided downstream of the permeability detector 20 for magnetically separating the magnetic Fe3O4Recovering the particles; permeability detector 20 is connected to the orifice for applying magnetic particles.
Example 1
The desizing wastewater based on polyacrylate size has the following basic water quality conditions: COD12000mg/L, BOD370mg/L, SS 65mg/L, pH12 and light yellow color; after the temperature is reduced by a heat pump system, firstly, concentrating the wastewater by adopting a tubular ceramic membrane with the average pore diameter of 20nm at the flow rate of 2m/s, adding water for dialysis in the concentration process, stopping dialysis when the pH value of penetrating fluid is reduced to about 10, and recycling the concentrated solution as recycled polyacrylate slurry; adding mixed acid consisting of sulfuric acid and hydrochloric acid into penetrating fluid to adjust the pH value to about 8.5, adding 1.5% of ferrous sulfate and 30mg/L of coagulant aid polyacrylamide, coagulating, filtering coagulated wastewater at the flow rate of 3m/s by adopting a 200nm tubular ceramic membrane to remove alum floc, adding lime into filtrate to generate calcium sulfate precipitate, raising the temperature from 20 ℃ to 50 ℃ by using a heat pump system, filtering the precipitate at the flow rate of 3m/s by using a 50nm tubular ceramic membrane, concentrating and drying the obtained precipitate, and taking the calcium sulfate as a raw material for making bricks; adding 200ppm ozone into the filtrate, reacting at 45 deg.C for 30min, and filtering with nanofiltration membrane with molecular weight cutoff of 400Da to obtain reuse water.
Example 2
Compared with the embodiment 1, the heat pump system is not adopted to transfer the heat of the desizing wastewater into the precipitated wastewater.
Example 3
Compared with the example 1, 0.5wt% nitric acid modified Fe is added in the process of lime precipitation3O4Magnetic particles. Which is prepared by mixing Fe3O4The magnetic particles are obtained after being soaked in nitric acid, and the surfaces of the magnetic particles are positively charged.
The desizing wastewater based on polyacrylate size has the following basic water quality conditions: COD12000mg/L, BOD370mg/L, SS 65mg/L, pH12 or so, light yellow; after the temperature is reduced by a heat pump system, firstly, concentrating the wastewater by adopting a tubular ceramic membrane with the average pore diameter of 20nm at the flow rate of 2m/s, adding water for dialysis in the concentration process, stopping dialysis when the pH value of penetrating fluid is reduced to about 10, and recycling the concentrated solution as recycled polyacrylate slurry; adding mixed acid of sulfuric acid and hydrochloric acid into the penetrating fluid to adjust pH to about 8.5, and adding 1.5% ferrous sulfate and 30%Coagulating the mg/L coagulant aid polyacrylamide, filtering the coagulated wastewater by adopting a 200nm tubular ceramic membrane at the flow speed of 3m/s to remove alum flocs, and adding lime and nitric acid modified Fe into the filtrate3O4Magnetic particles are generated to generate calcium sulfate sediment, after the temperature is raised from 20 ℃ to 50 ℃ through a heat pump system, the sediment is filtered through a 50nm tubular ceramic membrane at the flow rate of 3m/s, and the magnetic permeability in the cross-flow effluent liquid is judged in real time in the filtering process so as to identify potential filter cake blockage in a membrane channel; after the obtained concentrated and dried, calcium sulfate is used as a raw material for making bricks; adding 200ppm ozone into the filtrate, reacting at 45 deg.C for 30min, and filtering with nanofiltration membrane with molecular weight cutoff of 400Da to obtain reuse water.
Example 4
In comparison with example 3, Fe which had not been modified with nitric acid was added3O4Magnetic particles.
The water quality of the treated wastewater in the above examples is shown in the following table:
Figure DEST_PATH_IMAGE002
as can be seen from the above table, the integrated process provided by the invention can effectively recover the polyacrylate size in the desizing wastewater, and the water quality can reach the recycling standard after the subsequent coagulation, precipitation, ozone oxidation and nanofiltration treatment.
After the precipitation reaction of calcium sulfate, the wastewater is filtered by a ceramic membrane, sulfate ions introduced from a coagulant in the wastewater in the process of adjusting the pH value can be converted into calcium sulfate precipitate, and the method can be applied to the process of making bricks for buildings.
In the above process, by comparing the embodiment 1 with the embodiment 2, because the high heat in the desizing wastewater is transferred to the wastewater in the ceramic membrane filtering process under the action of the heat pump, the temperature of the wastewater entering the ceramic membrane is increased, the viscosity of water is reduced, and the permeability of water in the membrane pores is improved; as can be seen from the flux decay curve in fig. 2 for the precipitated wastewater process, the flux in example 2 is significantly lower than that in example 1, illustrating that the heat in the desized wastewater can be reused again to the filtration process of the ceramic membrane by the above-described improved method.
Fe modified by nitric acid during the filtration of ceramic membranes3O4The magnetic particles can coat calcium sulfate precipitation on the surfaces of the particles through electrostatic action in the precipitation process, so that the particle size of the particles is improved, the blockage and pollution of membrane pores of the tubular ceramic membrane are avoided, and the flux is improved. The flux change of the tubular ceramic membrane obtained in the above example when the calcium sulfate precipitation wastewater is filtered is shown in fig. 2, and it can be seen from the figure that the flux of the ceramic membrane decays slowest when the nitric acid modified magnetic particles used in example 3 are used for auxiliary filtration; SEM photographs of the filter cakes obtained in examples 3 and 4 are shown in FIG. 3, from which it can be seen that Fe having a positively charged surface is present3O4The particles of the cake layer after magnetic particle assisted deposition are significantly larger. At the same time, Fe3O4When the magnetic particles flow out from the interception side channel, the magnetic permeability of the pipeline can be changed according to the content of the particles, and whether the pipeline of the tubular ceramic membrane is blocked or not can be judged according to the outflow quantity because the addition quantity is a certain value.

Claims (10)

1. A zero-emission treatment process for printing and dyeing wastewater is characterized by comprising the following steps:
step 1, feeding printing and dyeing wastewater into a first tubular ceramic membrane filter for filtering, and concentrating slurry;
step 2, adjusting the pH of the filtrate obtained by the first tubular ceramic membrane filter, and adding a coagulant for coagulation;
step 3, filtering the wastewater obtained in the step 2 by adopting a second tubular ceramic membrane filter to remove alum flocs;
step 4, adding lime into the filtrate obtained in the step 3 to precipitate sulfate ions;
step 5, filtering the wastewater obtained in the step 4 by adopting a third tubular ceramic membrane filter to remove precipitates;
step 6, carrying out ozone oxidation treatment on the filtrate obtained in the step 5;
and 7, filtering the wastewater obtained in the step 6 by adopting a nanofiltration membrane.
2. The process of zero discharge of printing and dyeing wastewater according to claim 1, characterized in that, preferably, the printing and dyeing wastewater is desizing wastewater using polyacrylate as sizing agent;
preferably, the water quality of the desizing wastewater is: COD is 5000-30000mg/L, BOD 200 is 500mg/L, SS is 30-90mg/L, pH is 9-13, and the color is light yellow;
preferably, in the step 1, heat in the printing and dyeing wastewater is obtained through an evaporator, and is transferred to the wastewater entering the third tubular ceramic membrane filter for filtering in the step 5 through a heat pump system;
preferably, the average pore size of the first tubular ceramic membrane filter is in the range of 8-20nm, and the cross-flow speed during filtration is 1-5 m/s;
preferably, in step 1, dialysis with water is also required during concentration.
3. The zero-emission treatment process of printing and dyeing wastewater according to claim 1, characterized in that, preferably, the pH adjustment in the step 2 is performed by using a mixed acid of sulfuric acid and hydrochloric acid, and the pH is adjusted to 8.0-9.0;
preferably, the coagulant is ferrous sulfate, and the addition amount of the coagulant is 0.5-2 g/L; and the coagulant aid polyacrylamide can be added while coagulating, and the adding amount is 20-40 mg/L.
4. The zero-emission treatment process of printing and dyeing wastewater as claimed in claim 1, characterized in that, preferably, the average pore size of the second tubular ceramic membrane filter in step 3 is 200-800nm, and the cross flow speed during the filtration process is 2-5 m/s;
preferably, the addition amount of lime in step 4 is converted from the stoichiometric amount of sulfate ions in the completely precipitated wastewater;
preferably, the third tubular ceramic membrane filter has an average pore size in the range of 50 to 200nm and a cross-flow velocity during filtration of 1 to 5 m/s;
preferably, the concentrated solution containing calcium sulfate obtained by the third tubular ceramic membrane filter is used as a building material after calcium sulfate is recovered by plate-and-frame filtration.
5. The zero-emission treatment process of printing and dyeing wastewater according to claim 1, characterized in that, preferably, when lime is added, magnetic particles are also added, and the addition amount is 0.2-0.5 wt%; detecting the magnetic conductivity in the pipeline in real time at a feed liquid outlet at the interception side of the third tubular ceramic membrane filter (12) through a magnetic conductivity detector (20), and stopping the third tubular ceramic membrane filter when the magnetic conductivity is lower than a threshold value, and cleaning a filter channel;
preferably, the magnetic particles are also recovered magnetically by an online magnetic separator (21) on the downstream side of the magnetic permeability detector (20), and the recovered magnetic particles are quantitatively dosed to the precipitation reaction in step 4;
preferably, the magnetic particles are nitric acid modified Fe3O4Magnetic particles, the particle size range is 200-500 nm.
6. The zero discharge treatment process of printing and dyeing wastewater according to claim 1, characterized in that, preferably, the amount of ozone added can be 100-300ppm, the temperature of ozone reaction can be 40-50 ℃, and the reaction time is 30-60 min;
preferably, a ceramic nanofiltration membrane (15) is used in the step 7, and the molecular weight cut-off is 200-400 Da.
7. A zero discharge system of printing and dyeing wastewater is characterized by comprising:
the desizing waste liquid tank (1) is used for storing desizing waste water;
the first tubular ceramic membrane filter (2) is connected to the desizing waste liquid tank (1) and is used for carrying out slurry concentration treatment on the desizing waste water;
the water filling port (3) is connected with the feed port of the first tubular ceramic membrane filter (2) and is used for performing water filling dialysis treatment on the dialyzate of the first tubular ceramic membrane filter (2);
the coagulation tank (4) is connected to the permeation side of the first tubular ceramic membrane filter (2) and is used for carrying out coagulation treatment on the permeation liquid obtained by the first tubular ceramic membrane filter (2);
the acid adding port (5) is connected with the coagulation tank (4) and is used for adjusting the pH of the penetrating fluid obtained by the first tubular ceramic membrane filter (2);
a coagulant addition port (6) connected to the coagulation tank (4) and used for adding a coagulant into the coagulation tank (4);
the second tubular ceramic membrane filter (7) is connected to the coagulation tank (4) and is used for filtering the wastewater after coagulation reaction to remove a coagulation body;
the precipitation reaction tank (9) is connected to the permeation side of the second tubular ceramic membrane filter (7) and is used for carrying out a sulfate ion precipitation reaction on the penetrating fluid obtained by the second tubular ceramic membrane filter (7);
a lime adding port (11) connected to the precipitation reaction tank (9) and used for adding lime into the precipitation reaction tank (9);
the third tubular ceramic membrane filter (12) is connected with the precipitation reaction tank (9) and is used for filtering the wastewater after the precipitation reaction to remove the precipitate;
the second plate-and-frame filter press (13) is connected to the interception side of the third tubular ceramic membrane filter (12) and is used for carrying out solid-liquid separation on the obtained concentrated solution;
the ozone reaction tank (14) is connected to the permeation side of the third tubular ceramic membrane filter (12) and is used for carrying out ozone oxidation treatment on the penetrating fluid of the third tubular ceramic membrane filter (12);
and the ceramic nanofiltration membrane (15) is connected to the ozone reaction tank (14) and is used for performing nanofiltration separation treatment on the wastewater treated in the ozone reaction tank (14).
8. The zero discharge system of printing and dyeing wastewater according to claim 7 is characterized in that the first plate-and-frame filter press (8) is connected to the interception side of the second tubular ceramic membrane filter (7) for solid-liquid separation of the concentrated solution;
preferably, an evaporator (16) is arranged in the desizing waste liquid tank (1), a condenser (18) is arranged in the precipitation reaction tank (9), a compressor (17) and an expansion valve (19) are further included, and the evaporator (16), the compressor (17), the condenser (18) and the expansion valve are connected in sequence to form a closed cycle.
9. The zero discharge system of printing and dyeing wastewater according to claim 7, characterized by that, preferably, the average pore size of the first tubular ceramic membrane filter (1) is in the range of 8-20 nm;
preferably, the average pore size of the second tubular ceramic membrane filter (7) is in the range of 200-800 nm;
preferably, the third tubular ceramic membrane filter (12) has an average pore size in the range of 50 to 200 nm; preferably, the device also comprises a magnetic particle adding port (10) for adding magnetic Fe into the precipitation reaction tank (9)3O4Particles;
preferably, a magnetic permeability detector (20) is arranged on an outlet pipeline on the interception side of the third tubular ceramic membrane filter (12) and is used for detecting the magnetic permeability of the outlet pipeline in real time; an on-line magnetic separator (21) is arranged at the downstream of the magnetic permeability detector (20) and is used for magnetically separating magnetic Fe3O4Recovering the particles; the magnetic permeability detector (20) is connected to the magnetic particle adding port.
10. Use of the zero discharge system for printing and dyeing wastewater of claim 7 for treating desizing wastewater.
CN202010301534.3A 2020-04-16 2020-04-16 Zero-discharge treatment process and system for printing and dyeing wastewater Withdrawn CN111592137A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010301534.3A CN111592137A (en) 2020-04-16 2020-04-16 Zero-discharge treatment process and system for printing and dyeing wastewater

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010301534.3A CN111592137A (en) 2020-04-16 2020-04-16 Zero-discharge treatment process and system for printing and dyeing wastewater

Publications (1)

Publication Number Publication Date
CN111592137A true CN111592137A (en) 2020-08-28

Family

ID=72187479

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010301534.3A Withdrawn CN111592137A (en) 2020-04-16 2020-04-16 Zero-discharge treatment process and system for printing and dyeing wastewater

Country Status (1)

Country Link
CN (1) CN111592137A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112573885A (en) * 2020-12-12 2021-03-30 南京霄祥工程技术有限公司 Self-leveling mortar and preparation method thereof

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112573885A (en) * 2020-12-12 2021-03-30 南京霄祥工程技术有限公司 Self-leveling mortar and preparation method thereof

Similar Documents

Publication Publication Date Title
CN109678280B (en) High-recovery-rate circulating water sewage desalination treatment recycling system of thermal power plant
CN100450592C (en) Metal smelting factory sewage reclaiming method based on membrane filtering technique
WO2022088379A1 (en) Method and device for using membrane method to treat titanium dioxide acidic wastewater to produce high-quality titanium gypsum by-product
CN208234724U (en) Advanced treatment and reuse of dyeing waste water and Zero emission device
CN111268819A (en) Process and device for recycling reclaimed water in titanium dioxide acid wastewater
CN101205105A (en) Regeneration treatment and cyclic utilization method of printing and dyeing wastewater
CN106745981A (en) A kind of system and method for high-salt wastewater treatment for reuse
CN210030227U (en) Concentration treatment device for chemical nickel plating rinsing wastewater
Broom et al. The treatment of heavy metal effluents by crossflow microfiltration
CN109179762A (en) A kind of processing method of molybdenum ore beneficiation wastewater
CN110981000A (en) Method for treating silicon steel magnesium oxide wastewater
CN111592137A (en) Zero-discharge treatment process and system for printing and dyeing wastewater
CN112028270A (en) Concentration treatment device and treatment method for chemical nickel plating rinsing wastewater
KR20040002594A (en) Liquid treatment method and apparatus
CN211921101U (en) Titanium dioxide acid waste water reuse of reclaimed water device
CN212102282U (en) Nickel-containing wastewater treatment system
CN112174382A (en) Semiconductor industrial wastewater treatment technology and recycling process
JP3688505B2 (en) Method and apparatus for treating fluorine-containing waste liquid
CN106995247A (en) The producing device and method of a kind of low sodium healthy water
CN111003859A (en) Zero-discharge treatment method and device for reclaimed water
CN216106354U (en) Novel ultrafiltration water treatment system
CN206529365U (en) A kind of Treated sewage reusing device of zero-emission
CN109133421B (en) A kind of advanced treatment of wastewater recycling system
CN211921154U (en) Zero-discharge treatment device for reclaimed water
CN111268845A (en) Zero-discharge treatment process and system for papermaking wastewater

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
WW01 Invention patent application withdrawn after publication
WW01 Invention patent application withdrawn after publication

Application publication date: 20200828