Special textile printing and dyeing wastewater separation and concentration treatment method and device

Abstract

The invention provides a special textile printing and dyeing wastewater separation and concentration treatment method which comprises the following steps: performing primary treatment on printing and dyeing wastewater to reduce the contents of suspended solids and organic matters in the printing and dyeing wastewater so as to obtain primary treatment wastewater; separating salt in the primary treatment wastewater by using a membrane separation technology to obtain clear liquid and salt-containing wastewater; carrying out deep concentration on the salt-containing wastewater to obtain concentrated wastewater; the clear liquid and the concentrated wastewater are respectively reused for production, so that recycling of the wastewater is realized. According to the treatment method disclosed by the invention, membrane separation and deep concentration are combined, so that the treatment efficiency of the printing and dyeing wastewater is relatively high, and the recycling and harmless treatment of the special textile printing and dyeing wastewater is effectively realized.

Description

Technical Field

[0001] The invention relates to the technical field of environmental protection, and in particular to a method and device for separating and concentrating special textile printing and dyeing wastewater. Background Art

[0002] In recent years, my country's economy has been developing rapidly. As an important part of light industry, the textile printing and dyeing industry has not only made significant contributions to the country's economic growth, but also played an irreplaceable role in improving employment and promoting international trade. Through continuous technological innovation and industrial upgrading, the industry has achieved comprehensive optimization from raw material processing to finished product manufacturing, greatly enriched the market supply, and met the increasingly diversified needs of consumers.

[0003] However, the rapid development of the textile printing and dyeing industry has also brought about environmental challenges that cannot be ignored. In the production process, a large amount of dyes, auxiliaries and chemical agents are used, resulting in huge wastewater discharge and extremely high pollutant concentrations. These wastewaters contain not only difficult-to-degrade organic pollutants, but also harmful components such as heavy metal ions, acid and alkali substances. The complexity of its components and the difficulty of treatment pose a serious threat to natural water bodies and the ecological environment. Traditional wastewater treatment technologies, such as physical precipitation, chemical coagulation, and biodegradation, often fail to achieve ideal purification effects when facing special textile printing and dyeing wastewater, and are difficult to meet increasingly stringent environmental regulations and standards.

[0004] In particular, with the enhancement of environmental awareness and the popularization of green production concepts, the requirements of all sectors of society for wastewater treatment in the textile printing and dyeing industry are constantly increasing. Traditional treatment processes are not only limited in treatment efficiency, but may also cause secondary pollution, which is not conducive to sustainable development.

[0005] In this context, exploring a new treatment technology for special textile printing and dyeing wastewater has become an important issue to be solved.

[0006] In view of this, the present invention is proposed. Summary of the invention

[0007] The first purpose of the present invention is to provide a method for separating and concentrating special textile printing and dyeing wastewater. The treatment method adopts a combination of membrane separation and evaporation concentration technology, has high treatment efficiency, and can effectively realize the resource utilization and harmless treatment of special textile printing and dyeing wastewater.

[0008] The second object of the present invention is to provide a special textile printing and dyeing wastewater separation and concentration device, which is used to implement the above-mentioned special textile printing and dyeing wastewater separation and concentration method. The treatment device has a compact structure, occupies a small area, and is easy to operate and maintain.

[0009] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are particularly adopted: A method for separating and concentrating special textile printing and dyeing wastewater comprises the following steps: First, the printing and dyeing wastewater is preliminarily treated to reduce the content of suspended solids and organic matter in the printing and dyeing wastewater to obtain preliminarily treated wastewater; membrane separation technology is used to separate the salt in the preliminarily treated wastewater to obtain clear liquid and saline wastewater; the saline wastewater is deeply concentrated to obtain concentrated wastewater; the clear liquid and concentrated wastewater are respectively reused in production to realize the resource utilization of wastewater.

[0010] Preferably, the preliminary treatment step includes primary treatment and secondary treatment, the primary treatment is to filter the printing and dyeing wastewater to obtain filtered wastewater, and the secondary treatment is to adjust the pH value of the filtered wastewater.

[0011] Preferably, in the secondary treatment step, at least one of a sodium sulfate solution and a sodium chloride solution is used to adjust the pH value of the filtered wastewater.

[0012] Preferably, the membrane separation technology uses a nanofiltration membrane or a reverse osmosis membrane.

[0013] Preferably, the saline wastewater generated in the membrane separation technology step is subjected to tertiary treatment, and the tertiary treatment is to filter the saline wastewater.

[0014] Preferably, the deep concentration is to evaporate and concentrate the saline wastewater to obtain concentrated wastewater.

[0015] Specifically, through the primary treatment, that is, filtration, the large suspended solids and fiber debris in the printing and dyeing wastewater are effectively removed, which reduces the difficulty and cost of subsequent treatment and improves the overall efficiency of printing and dyeing wastewater treatment. The secondary treatment, that is, pH adjustment, uses sodium sulfate solution or sodium chloride solution to adjust the pH value of the printing and dyeing wastewater, optimizes the conditions for wastewater treatment, and ensures that the wastewater is in the best treatment conditions. The use of nanofiltration membranes or reverse osmosis membranes for membrane separation can efficiently and accurately separate the salt and clear liquid in the wastewater. The clear liquid can be directly reused, and the saline wastewater enters the next step of treatment. Membrane separation technology uses nanofiltration membranes or reverse osmosis membranes, which can efficiently and accurately separate the saline wastewater and clear liquid in the printing and dyeing wastewater. The clear liquid is directly reused, reducing the demand for fresh water and reducing wastewater discharge. The tertiary treatment further removes the suspended solids content in the saline wastewater, ensures that the subsequent concentration process is not disturbed, and improves the quality of the concentrated wastewater. The deep concentration step removes water from the salt-containing wastewater. The concentrated wastewater and salt obtained can be reused in production, such as cooling water, cleaning water or chemical raw materials for textile printing and dyeing, thus maximizing the utilization of resources.

[0016] The treatment process achieves comprehensive purification and resource utilization of printing and dyeing wastewater through the organic combination of multiple steps such as preliminary treatment, membrane separation technology, tertiary treatment and deep concentration. The entire treatment process is efficient, energy-saving and environmentally friendly, which not only improves wastewater treatment efficiency and water resource utilization, but also promotes the sustainable development and resource conservation of printing and dyeing enterprises.

[0017] The present invention also provides a special textile printing and dyeing wastewater separation and concentration device, comprising: Treatment equipment, membrane separation equipment, and deep concentration equipment are arranged in sequence along the direction of the printing and dyeing wastewater inflow; The treatment equipment is specifically a place where the printing and dyeing wastewater is preliminarily treated, in order to remove suspended matter in the printing and dyeing wastewater and adjust the pH value of the printing and dyeing wastewater to ensure the smooth progress of subsequent treatment steps; The membrane separation equipment uses a nanofiltration membrane, which can effectively preliminarily treat small molecular organic matter, salt and some heavy metal ions in the wastewater; The deep concentration treatment equipment is connected to the membrane separation equipment, specifically using a multi-effect evaporator to evaporate the water in the saline wastewater through a multi-stage evaporation and condensation process to obtain concentrated wastewater.

[0018] Preferably, a wastewater collection pool is connected in front of the treatment equipment, and the wastewater collection pool is used to collect the wastewater to be printed and dyed, so as to ensure the continuity of subsequent treatment steps.

[0019] The processing equipment contains filters and regulating equipment; The filter is the first step in the preliminary treatment of wastewater, and is used to remove suspended matter from printing and dyeing wastewater; The regulating device is connected to the filter, and a pH value regulator is provided in the device, so that the chemical agent can be evenly mixed with the printing and dyeing wastewater to adjust its pH value.

[0020] Preferably, the deep concentration device is connected to a storage tank for storing and reusing the processed salt.

[0021] Specifically, the treatment device uses the wastewater collection pool as the starting point, ensuring the continuous supply of printing and dyeing wastewater to be treated, and providing a stable foundation for the entire treatment process. The treatment equipment, membrane separation equipment and deep concentration equipment are set up in sequence to form a coherent treatment process. Each step provides suitable treatment conditions for the next step, ensuring the efficiency and stability of the entire treatment process.

[0022] As the first step of preliminary treatment, the filter effectively removes suspended solids in printing and dyeing wastewater, provides relatively clean water inlet for membrane separation equipment, and reduces the risk of membrane pollution. The regulating equipment accurately adjusts the pH value of wastewater through the pH regulator, optimizes membrane separation conditions, improves membrane separation efficiency and effluent quality, and forms a close combination of preliminary treatment and membrane separation.

[0023] The use of membrane separation equipment not only removes small molecular organic matter, salt and some heavy metal ions in printing and dyeing wastewater, but also provides purer saline wastewater for subsequent deep concentration. As a deep concentration equipment, the evaporator efficiently removes water from saline wastewater through multi-stage evaporation and condensation processes, obtains concentrated wastewater and salt, and realizes wastewater reduction and resource utilization. The setting of storage tanks stores and reuses the treated salt, forming a closed-loop treatment process, which further improves resource utilization.

[0024] The treatment device not only reduces the discharge volume of printing and dyeing wastewater and the concentration of pollutants, but also realizes the recycling of resources, conforms to the concept of environmental protection, and is conducive to protecting the natural environment and ecological balance.

[0025] Compared with the prior art, the present invention has the following beneficial effects: (1) The special textile printing and dyeing wastewater separation and concentration method provided by the present invention can significantly reduce the content of suspended matter, organic matter and salt in the printing and dyeing wastewater, and finally obtain clear liquid and concentrated wastewater, which are respectively reused in the textile production process. This treatment method not only reduces the discharge of wastewater, but also realizes the maximum utilization of water resources.

[0026] (2) In the initial treatment stage, the suspended solids are removed by primary treatment filtration, and the pH value of the printing and dyeing wastewater is adjusted by secondary treatment, which effectively reduces the burden of subsequent membrane separation and deep concentration equipment and improves the overall treatment efficiency. At the same time, the use of sodium sulfate solution and sodium chloride solution to adjust the pH value can achieve the adjustment effect and avoid the introduction of new pollutants.

[0027] (3) Using nanofiltration membrane or reverse osmosis membrane for membrane separation can effectively separate the salt in printing and dyeing wastewater while retaining valuable substances. The use of membrane separation technology not only improves the accuracy of printing and dyeing wastewater treatment, but also provides cleaner raw materials for subsequent concentration treatment.

[0028] (4) Use a multiple-effect evaporator for deep concentration. Through multi-stage evaporation and condensation processes, energy consumption is effectively reduced and treatment efficiency is improved. At the same time, the concentrated wastewater obtained can be directly reused in production or further processed, thus maximizing the utilization of resources.

[0029] (5) The special textile printing and dyeing wastewater separation and concentration device provided by the present invention integrates wastewater collection, treatment, membrane separation, deep concentration and other equipment, with a compact structure, small footprint and easy operation. At the same time, the connection design between the various devices is reasonable, which is convenient for daily maintenance and troubleshooting. (6) The entire printing and dyeing wastewater treatment process does not produce secondary pollution, which meets environmental protection requirements. At the same time, by recycling and reusing resources in wastewater, production costs are reduced and the economic benefits of printing and dyeing enterprises are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] By describing the embodiments of the present application in more detail in conjunction with the accompanying drawings, the above and other purposes, features and advantages of the present application will become more apparent. The accompanying drawings are used to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the present application and do not constitute a limitation of the present application. In the accompanying drawings, the same reference numerals generally represent the same components or steps. Figure 1 A schematic diagram of the overall process of a method for separating and concentrating special textile printing and dyeing wastewater provided in this application.

[0031] Specific implementation method The technical scheme of the present invention will be clearly and completely described below in conjunction with specific embodiments, but it will be appreciated by those skilled in the art that the following described embodiments are some embodiments of the present invention, rather than all embodiments, and are only used to illustrate the present invention, and should not be considered as limiting the scope of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work, all belong to the scope of protection of the present invention. If specific conditions are not indicated in the embodiments, they are carried out according to normal conditions or conditions recommended by the manufacturer. If the manufacturer is not indicated in the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0032] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with the implementation methods.

[0033] The present application provides a method for separating and concentrating special textile printing and dyeing wastewater. Specifically, in the present invention, along the inflow direction of the printing and dyeing wastewater, the printing and dyeing wastewater first flows into a wastewater collection pool. The wastewater collection pool is a pool with a large-capacity storage function, which is used to receive special textile printing and dyeing wastewater. The wastewater collection pool can control the flow rate and speed of the outflow of the printing and dyeing wastewater through an automatic water inlet component, so as to provide a more continuous and stable process for the subsequent treatment of the printing and dyeing wastewater.

[0034] The filter is connected to the wastewater collection pool. The filter is composed of a filter medium and a filter container. The filter medium is used to remove special suspended impurities in the printing and dyeing wastewater to ensure the normal operation of the subsequent treatment equipment. The adjustment device is connected to the filter. The adjustment device includes a pH value regulator. By measuring the pH value of the printing and dyeing wastewater and adding chemical agents as needed, the printing and dyeing wastewater is adjusted to a suitable pH range. Pipes and valves in the treatment device are susceptible to corrosion and damage under extreme pH conditions. Adjusting the pH value of the printing and dyeing wastewater to a suitable range can extend the service life of these equipment and reduce maintenance costs.

[0035] The membrane separation equipment is connected to the regulating equipment. The core of the specific membrane separation equipment is composed of one of the nanofiltration membranes or reverse osmosis membranes and their supporting structure, which is used to separate small molecular organic matter, salt and some heavy metal ions in printing and dyeing wastewater to obtain clear liquid and saline wastewater.

[0036] Specifically, a removal device is connected behind the membrane separation device, which can be an activated carbon adsorption device. The device can receive the clear liquid and saline wastewater sent by the membrane separation device; ensure that the pollutants in the clear liquid are completely removed to meet the discharge standards or higher water quality requirements; and further reduce the suspended matter content in the saline wastewater.

[0037] The deep concentration equipment is connected to the activated carbon adsorption equipment to further concentrate the treated saline wastewater. The saline wastewater is sent to an evaporator for evaporation and concentration to obtain concentrated wastewater and salt.

[0038] Specifically, the evaporator is a multiple-effect evaporator or a molecular distiller, and has a high evaporation efficiency.

[0039] Specifically, a storage tank is connected behind the deep concentration device to store, recycle and reuse the salt obtained by the evaporation and concentration process.

[0040] Example 1 The practical application of the process of separation and concentration of special textile printing and dyeing wastewater of the present invention is shown in Figure 1 As shown, the practical application of the special textile printing and dyeing wastewater treatment device of the present invention includes the following process: First, the printing and dyeing wastewater in the wastewater treatment station of the printing and dyeing enterprise is sent to the wastewater collection pool through pipelines, ensuring that the printing and dyeing wastewater can be centrally managed and providing a stable source of printing and dyeing wastewater for subsequent treatment. In the wastewater collection pool, the printing and dyeing wastewater will be temporarily stored and await further treatment; then, by controlling the automatic water inlet component, the printing and dyeing wastewater is accurately adjusted from the wastewater collection pool to the filter to remove impurities such as dye particles and fiber debris in the printing and dyeing wastewater to obtain primary treated wastewater, laying the foundation for subsequent treatment; after this, after primary treatment, the printing and dyeing wastewater enters the regulating equipment, that is, the secondary treatment, and uses sodium sulfate solution to adjust the pH value of the primary treated wastewater to obtain secondary treated wastewater, in order to reduce the burden on subsequent treatment equipment; then, the secondary treated wastewater enters the nanofiltration membrane separation equipment. , the clear liquid is separated from the saline wastewater by nanofiltration membrane technology; the clear liquid is recovered through a transportation device and reused in the textile production process; then the saline wastewater is subjected to tertiary treatment, and the saline wastewater enters the activated carbon adsorption equipment to further reduce the suspended matter content in the saline wastewater to obtain tertiary treated wastewater; then the tertiary treated wastewater is sent to a multiple-effect evaporator, and concentrated wastewater and salt are obtained after evaporation and concentration, and the concentrated wastewater is recycled into the production process of textile printing and dyeing through a transportation device, and the generated salt is stored in a storage tank for resource utilization.

[0041] Example 2 The specific implementation method is consistent with Example 1, except that the nanofiltration membrane separation equipment is replaced by a reverse osmosis membrane separation equipment, and the multiple-effect evaporator is replaced by a molecular distiller.

[0042] It can be seen that the present invention adopts a combination of membrane separation and evaporation concentration to carry out comprehensive and efficient purification of printing and dyeing wastewater. This treatment method not only effectively removes impurities such as dye particles and fiber debris in printing and dyeing wastewater, but also optimizes the treatment conditions by accurately adjusting the pH value, promotes the degradation of pollutants, and realizes the resource recovery and reuse of clear liquid and salt. This process not only significantly reduces the amount of wastewater discharged and the concentration of pollutants, reduces pollution to the environment, but also improves the treatment efficiency and reduces the treatment cost, providing strong support for the sustainable development and resource conservation of printing and dyeing enterprises.

[0043] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for separating and concentrating special textile printing and dyeing wastewater, characterized in that: The steps include: First, the printing and dyeing wastewater is preliminarily treated to reduce the content of suspended solids and organic matter in the printing and dyeing wastewater to obtain preliminarily treated wastewater; membrane separation technology is used to separate the salt in the preliminarily treated wastewater to obtain clear liquid and saline wastewater; the saline wastewater is deeply concentrated to obtain concentrated wastewater; the clear liquid and concentrated wastewater are respectively reused in production to realize the resource utilization of wastewater.

2. The method for separating and concentrating special textile printing and dyeing wastewater according to claim 1, characterized in that: The preliminary treatment step includes primary treatment and secondary treatment. The primary treatment is to filter the printing and dyeing wastewater to obtain filtered wastewater, and the secondary treatment is to adjust the pH value of the filtered wastewater.

3. The method for separating and concentrating special textile printing and dyeing wastewater according to any one of claims 1 to 2, characterized in that: In the secondary treatment step, at least one of a sodium sulfate solution and a sodium chloride solution is used to adjust the pH value of the filtered wastewater.

4. The method for separating and concentrating special textile printing and dyeing wastewater according to claim 1, characterized in that: The membrane separation technology uses a nanofiltration membrane or a reverse osmosis membrane.

5. The method for separating and concentrating special textile printing and dyeing wastewater according to claim 4, characterized in that: The saline wastewater generated in the membrane separation technology step is to be subjected to tertiary treatment, and the tertiary treatment is to filter the saline wastewater.

6. The method for separating and concentrating special textile printing and dyeing wastewater according to claim 1, characterized in that: The deep concentration is to evaporate and concentrate the salt-containing wastewater to obtain concentrated wastewater.

7. A device for separating and concentrating special textile printing and dyeing wastewater according to any one of claims 1 to 6, characterized in that: include: Treatment equipment, membrane separation equipment, and deep concentration equipment are arranged in sequence along the direction of the printing and dyeing wastewater inflow; The treatment equipment is specifically a place where the printing and dyeing wastewater is preliminarily treated, in order to remove suspended matter in the printing and dyeing wastewater and adjust the pH value of the printing and dyeing wastewater to ensure the smooth progress of subsequent treatment steps; The membrane separation equipment uses a nanofiltration membrane, which can effectively preliminarily treat small molecular organic matter, salts and some heavy metal ions in the wastewater; The deep concentration treatment equipment is connected to the membrane separation equipment, specifically using a multi-effect evaporator to evaporate the water in the saline wastewater through a multi-stage evaporation and condensation process to obtain concentrated wastewater.

8. The special textile printing and dyeing wastewater separation and concentration treatment device according to claim 7 is characterized in that: A wastewater collection pool is connected in front of the treatment equipment, and the wastewater collection pool is used to collect the wastewater to be printed and dyed, so as to ensure the continuity of subsequent treatment steps.

9. The special textile printing and dyeing wastewater separation and concentration treatment device according to claim 7 is characterized in that: The processing equipment contains filters and regulating equipment; The filter is the first step in the preliminary treatment of wastewater, and is used to remove suspended matter from printing and dyeing wastewater; The regulating device is connected to the filter, and a pH value regulator is provided in the device, so that the chemical agent can be evenly mixed with the printing and dyeing wastewater to adjust its pH value.

10. The special textile printing and dyeing wastewater separation and concentration treatment device according to claim 7, characterized in that: The deep concentration device is connected to a storage tank for storing and reusing the processed salt.

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