This standard was drafted in accordance with the rules given in GB / T 1.1-2009.
This standard is proposed and supervised by the Shandong Provincial Department of Ecology and Environment.
This standard is under the jurisdiction of the Shandong Environmental Protection Standardization Technical Committee.
This standard was drafted: Shandong Jianzhu University, Shandong Institute of Environmental Planning.
The main drafters of this standard: Xing Lizhen, Zhang Zhibin, Shi Huijian, Zhang Xiangyang, Yang Yifei, Chen Wenbing, Li Tikang, Zhang Yanhao, Kong Jin, Liu Minglei, Wang Zifan, Zhang Weikang, Chen Dongchen.
Technical specifications for pollution control and treatment of high-salt wastewater in textile printing and dyeing industry
This standard specifies the technical requirements for the design, construction, acceptance, operation and maintenance of high-salt wastewater pollution control and treatment projects in the textile printing and dyeing industry.
This standard applies to the clean production of the textile printing and dyeing industry and the design, construction, acceptance, operation and maintenance of high-salt wastewater treatment projects. It can be used as a technical basis for the design, construction, acceptance, and operation and management of high-salt wastewater treatment projects.
2 Normative references
The following documents are essential for the application of this document. For dated references, only the dated version applies to this document. For undated references, the latest version (including all amendments) applies to this document.
GB 4287 Water Pollutant Discharge Standard for Textile Dyeing and Finishing Industry
GB / T 5657 Technical Conditions for Centrifugal Pumps (Class III)
GB / T 6909 Boiler water and cooling water analysis methods-Determination of hardness
GB / T 7477 Water quality-Determination of total calcium and magnesium-EDTA titration method
GB 12801 General requirements for safety and health requirements during production
GB 13200 Determination of water turbidity
GB / T 18920 Urban Wastewater Reuse and Urban Miscellaneous Water Quality
GB 50069 Code for structural design of water supply and drainage engineering structures
GB / T 50109 Design code for industrial water softening and desalination
GB 50141 Code for construction and acceptance of water supply and drainage structures
HCRJ 030 Electrodialyzer
HJ / T 51 Water quality-Determination of total salt content-Gravimetric method
HJ / T 92 Technical Specification for Total Water Pollutant Discharge Monitoring
HJ / T 185 Clean Production Standard Textile Industry (Cotton Printing and Dyeing)
HJ / T 270 Technical requirements for environmental protection products
HJ / T 369 Technical requirements for environmental protection products Dosing device for water treatment
HJ 471 Technical Specification for Wastewater Treatment Engineering of Textile Dyeing and Finishing Industry
HJ 579 Technical Specifications for Membrane Separation Wastewater Treatment Engineering
HJ 2008 Technical Specifications for Sewage Filtration Engineering
HJ 2010 Technical Specifications for Membrane Biological Wastewater Treatment Engineering
HY / T 034.2 Electrodialysis technology
HY / T 034.3 Electrodialysis technology
HY / T 034.4 Desalination method by electrodialysis technology
HY / T 061 hollow fiber microfiltration membrane module
HY / T 112 ultrafiltration membrane and its components
DB37 / T 3536—2019
HY / T 113 Nanofiltration membrane and its components
HY / T 120 Electrodeionized Membrane Stack (Component)
FZ / T 01107 Water quality of recycled water for textile dyeing and finishing industry
DB37 / 3416.1 Comprehensive discharge standards for water pollutants in river basins Part 1: Nanping Lake Dongping Lake Basin
DB37 / 3416.2 Comprehensive discharge standards for water pollutants in river basins Part 2: Yishui River Basin
DB37 / 3416.3 Comprehensive discharge standards for water pollutants in river basins Part 3: Xiaoqing River Basin
DB37 / 3416.4 Comprehensive discharge standards for water pollutants in basins Part 4: Haihe Basin
DB37 / 3416.5 Comprehensive discharge standards for water pollutants in watersheds Part 5: Peninsula watershed
3 terms and definitions
The terms and definitions defined in HJ 471 and the following apply to this document.
3.1 High salinity wastewater
Discharged by printing, dyeing and finishing, desizing, scouring, mercerizing, bleaching, alkali reduction, etc., and exceeding the comprehensive discharge standards for water pollutants in the basins of Shandong Province DB37 / 3416.1, DB37 / 3416.2, DB37 / 3416.3, DB37 / 3416.4 Wastewater with full salt discharge limits specified in DB37 / 3416.5.
3.2 Total salt
The total mass of all soluble salts per unit volume of wastewater can be passed through a 0.45 μm pore filter or filter and dried at 105 ℃ ¡À 2 ℃ to a constant weight of sediment (if there is too much organic matter, peroxidation should be used Hydrogen treatment) in milligrams per liter (mg / L).
3.3 Separate Treatment
The process of separate collection and treatment of high-salt wastewater discharged in certain production processes.
3.4 Desalination Pretreatment
Technical measures taken before desalination when the conventional treatment cannot meet the requirements of the influent water quality of the desalination unit.
3.5 Electrodeionization (EDI)
The fresh water chamber of electrodialysis is filled with an ion exchange resin, and electrodialysis and ion exchange are used for desalination.
3.6 Multiple-effect evaporation (MED)
Several evaporators are operated in series, and the salt is crystallized into a solid by evaporating water in the brine by heating. Through a series of steaming
This operation can make steam heat energy used more than once, which can improve the utilization rate of heat energy.
3.7 Mechanical vapor recompression (MVR)
The secondary steam generated by the evaporation system itself and its energy are used to perform work by being compressed by a steam compressor to increase the enthalpy of the secondary steam, which is guided into the cooling tower, and the cooling water of the cooling tower circulates to preheat the material, so that the circulation provides heat energy to the evaporation system so that An energy-saving technology that separates salt from water, thereby reducing the need for external energy.
3.8 Multistage flash evaporation (MSF)
Flash evaporation refers to the sudden evaporation of water at a certain temperature when the ambient pressure is lower than the saturated vapor pressure corresponding to the temperature. Multi-stage flash evaporation is a process in which the salt water heated to a certain temperature is sequentially flash-vaporized in a series of gradually decreasing pressure vessels. After the steam condenses, fresh water is obtained and the salt crystallizes.
3.9 Salt separation
The process of purifying, separating and recovering the miscellaneous salts in wastewater.
4 Wastewater quantity and water quality
4.1 Design water volume
4.1.1 The design water quantity of wastewater treatment project can be determined by referring to HJ 471.
4.1.2 New (expanded, rebuilt) enterprises should determine the design water volume of desalination workshops by analogy or material balance based on the type and amount of raw materials, product types, clean production levels, etc. The existing enterprises should base on the measured water volume .
4.2 Designed water quality
4.2.1 The design water quality of wastewater treatment project can be determined with reference to HJ 471.
4.2.2 New (expanded, rebuilt) enterprises should determine the design water quality of desalination plants by analogy according to the types and amounts of raw materials, product categories, clean production levels, etc. The existing enterprises should be based on the measured water quality.
5 General requirements
5.1 General provisions
5.1.1 The design of high-salt wastewater treatment projects shall comply with the relevant regulations of HJ 471.
5.1.2 The water and by-products of high-salt wastewater treatment projects shall be comprehensively utilized.
5.1.3 It is advisable to carry out comprehensive utilization or salt separation treatment of the concentrated brine produced during the treatment of high-salt wastewater, and the unusable concentrated brine should be solidified at the end or discharged to the sea for disposal as permitted by policy.
5.2 Construction scale
5.2.1 The construction scale of wastewater treatment project can be determined with reference to HJ 471.
5.2.2 The desalination unit is designed according to the highest daily average hourly flow.
5.3 Engineering composition
5.3.1 The composition of wastewater treatment project shall be added with desalination unit on the basis of meeting HJ 471 requirements.
5.3.2 The structures and equipment of the desalination unit mainly include: desalination pretreatment facilities and equipment, desalination workshop and equipment, evaporation or freezing workshop and equipment, etc.
5.4 Site selection
The site selection of the wastewater treatment project should comply with the relevant regulations of HJ 471.
5.5 General layout
5.5.1 The general layout of the wastewater treatment project shall comply with the relevant regulations of HJ 471.
5.5.2 When adding a desalination unit to the original wastewater treatment project, overall consideration should be given to the relationship between the original wastewater treatment facility and the new desalination facility, and a reasonable layout should be made.
6 Pollution control during production
6.1.1 Encourage enterprises to adopt clean production processes and advanced equipment to reduce the amount of total salt produced in wastewater.
6.1.2 Enterprises should reduce waste water discharge and total salt discharge through measures such as improving management levels, adjusting process parameters, changing production processes, adjusting production auxiliary materials, and recycling waste.
6.2 Production process selection
6.2.1 Priority should be given to less-water or anhydrous dyeing and finishing processes, and low-salt or non-salt dyeing processes.
6.2.2 Water-saving production processes and production processes with low pollutant emissions should be adopted.
6.2.3 The clean production of cotton printing and dyeing production process shall meet the requirements of HJ / T 185.
6.3 Use of dyes
Environmentally friendly dyes should be used, and low salt consumption dyes are preferred.
6.4 Selection of additives
Low-salt auxiliaries or salt substitutes should preferably be used.
6.5 Recycling of Wastewater and Waste Salt
6.5.1 Encourage recycling and reuse of wastewater. Recycled water reuse should meet the following requirements:
a) The reclaimed water should be reused for pre-treatment processes and miscellaneous water in the plant area, and part of it should be used for dyeing processes;
b) The quality of reused water should meet the requirements of FZ / T 01107, GB / T 18920, etc. according to the reuse route.
6.5.2 The purified waste salt should be recycled.
7 Wastewater treatment process design
7.1.1 The wastewater treatment process with mature technology, high treatment efficiency, energy saving, and low investment should be selected to ensure stable, reliable and safe operation of high-salt wastewater treatment projects.
7.1.2 The general process of high-salt wastewater treatment is: conventional treatment—desalting pretreatment—desalting treatment.
7.1.3 Different production processes should be distinguished, and salty wastewater should be classified according to the level of its total salt content.
7.1.4 When relying on conventional sewage treatment facilities for desalination treatment, the existing facilities should be used as much as possible.
7.2 General handling
7.2.1 Routine treatment shall meet the requirements of HJ 471. Appropriate treatment technical routes should be determined according to factors such as treatment scale, water quality characteristics, pollutant discharge standards, and drainage pathways, and they should be determined after technical and economic comparison.
7.2.2 Before the wastewater enters the desalination unit, combined processes such as physical, biological, chemical, and physical and chemical processes should be used for conventional treatment, and biological treatment processes should be preferentially used; biological treatment should be combined with anaerobic and aerobic technologies.
7.2.3 When the coagulation method is adopted for treatment, the amount of coagulant should be determined through field tests, and it should not be overdosed.
7.3 Desalination pretreatment
7.3.1 If the turbidity or hardness of the wastewater after conventional treatment cannot meet the requirements, it should be pretreated before entering the desalination unit.
7.3.2 When the turbidity cannot meet the requirements, it is advisable to select pretreatment technologies such as media filtration, microfiltration and ultrafiltration through technical and economic comparison to remove particulate matter in the water and reduce the turbidity of the wastewater.
7.3.3 When media filtration is used as a pretreatment process, it should be designed according to the relevant requirements in HJ 2008; when microfiltration or ultrafiltration is used as a pretreatment process, it should be designed according to the relevant requirements in HJ 579; MBR is used as a pretreatment When processing the process, the membrane stacker should be designed according to the requirements in HJ 2010.
7.3.4 Influent turbidity of submerged ultrafiltration membrane shall be controlled below 50 NTU, and influent turbidity of external ultrafiltration membrane shall be controlled below 20 NTU.
7.3.5 When the hardness can not meet the requirements, the hardness of wastewater should be reduced by ion exchange method or chemical method. When ion exchange technology is used to soften wastewater, strong acid ion exchange resin should be selected, and hydrochloric acid should be used as the regenerant.
7.4.1 According to the scale of wastewater treatment, the amount of total salt, the type of salt, etc., technologies such as membrane treatment, electrosalt removal (EDI), electrodialysis, high-temperature evaporation, or freeze crystallization should be selected through technical and economic comparison, or a combination of multiple technologies Use for brine separation. The following processes are recommended:
a) Membrane treatment. Membrane treatment method can adopt nanofiltration and reverse osmosis processes, etc., the process flow is shown in Figure 1;
b) Electrochemical method. The electrochemical method can use EDI and electrodialysis. The process flow is shown in Figure 2;
c) Evaporation or freezing. The evaporation method can adopt processes such as mechanical compression evaporation, multi-effect evaporation, and multi-stage flash evaporation; freezing crystallization technology is suitable for the purification of salts in high-concentration brine. See Figure 3 for the process flow.
7.4.2 Wastewater with a low total salt content should be desalted by nanofiltration, reverse osmosis
, and electrochemical techniques; solidification treatment of concentrated water that cannot be comprehensively used in the desalting process should be performed by evaporation crystallization or freeze crystallization .
7.4.3 Wastewater with a high total salt content should be desalinated by techniques such as evaporation and freezing.
7.4.4 When using nanofiltration or reverse osmosis technology for desalination, the following regulations shall be implemented:
a) The inlet silt density index (SDI) should be controlled below 3, the inlet turbidity should be controlled below 1NTU, and it must not contain free chlorine;
b) Classification treatment should be carried out. The inlet pressure of nanofiltration should be 1.0 ～ 1.5 MPa, and the inlet pressure of reverse osmosis should be 1.5 ～ 2.0 MPa. The velocity of the branch pipes and main pipes of the water production should be less than or equal to 1.0 m / s;
c) The hardness of the inlet water of the reverse osmosis (RO) membrane should be controlled below 300 mg / L, and the inlet water of the dish-type reverse osmosis (DTRO) membrane should be controlled below 600 mg / L.
Unless otherwise specified, it shall comply with the relevant regulations in HJ 579. http://euhowblog.com/
7.4.5 The design of the electrodialyzer shall meet the requirements of HY / T 034.4 and HCRJ 030.
7.4.6 It is advisable to select technologies such as mechanical compression evaporation, multi-stage flash evaporation or multi-effect evaporation desalting through technical and economic comparison to crystallize the salt in concentrated brine.
7.4.7 The hardness of the inlet water of the evaporation crystallization process should be controlled below 300 mg / L; multi-effect evaporation should use 3 to 4 effects, and the effective temperature difference between each effect should not be less than 5 ℃ ~ 7 ℃; the concentration rate in the flash evaporation process should be 1.5 ~ 2.0.
7.4.8 When using frozen crystallization, the freezing end temperature should be reasonably determined according to the type and proportion of salt in concentrated brine, so that the main salts will precipitate after crystallization, and the mother liquor with a lower concentration after crystallization returns to the previous stage of the dissolution process to participate in dissolution and crystallization .
7.5 Salt curing and recycling
7.5.1 Concentrated water produced after membrane or electrochemical treatment is discharged directly into the deep sea without conditions, and salt solidification should be performed:
a) When the total salt content of concentrated water is ≥50 000 mg / L, membrane separation method should be used to further concentrate the concentrated water and reuse the produced water or discharge it after reaching the standard;
b) When the total salt content of concentrated water is 50 000 mg / L ～ 100 000 mg / L, it is better to choose membrane concentration and solidification treatment or direct solidification treatment according to the water quality and economic level;
c) When the total salt content of concentrated water is ≥ 100 000 mg / L, the evaporation solidification or frozen crystallization salt treatment method should be selected.
7.5.2 For the wastewater whose sodium salt or sodium chloride accounts for more than 80% of the total salt content, the freezing crystallization method and evaporation method should be used to purify and recover the salt.
8 Prevention of secondary pollution
8.1.1 The secondary pollution prevention and control of wastewater treatment projects shall comply with the relevant regulations of HJ 471.
8.1.2 The waste salt that has many impurities and cannot be used should be disposed of safely. The disposal of waste salt should comply with HJ 471 and other relevant regulations.
8.1.3 The desalination treatment shall ensure that no excessive discharge of other pollutants is caused.
8.2 Accidents and emergency response
Accidents and emergency treatment should comply with HJ 471 and relevant national and local environmental emergency management regulations.
9 Main process equipment and materials
9.1.1 The equipment commonly used in routine treatment engineering shall meet the relevant requirements of HJ 471.
9.1.2 The equipment commonly used in desalination processing units includes centrifugal pumps, suction pumps or vacuum pumps, gas-water separation tanks, mixers, dosing equipment, lifting equipment, evaporators, crystallizers, etc.
9.1.3 Materials commonly used in desalination treatment projects are usually MBR membrane module, ultrafiltration membrane module, nanofiltration membrane module, reverse osmosis membrane module, EDI module, electrodialysis module, ion exchange resin, etc.
9.1.4 Corrosion-resistant equipment or components, pipes and materials commonly used in desalination units shall adopt corresponding anti-corrosion measures and meet the relevant national standards.
9.2 Configuration requirements
9.2.1 Dosing equipment shall be configured separately according to the nature of the liquid to be added and the treatment series.
9.2.2 High-power equipment such as centrifugal pumps, suction pumps and dosing pumps should be equipped with frequency conversion devices.
9.2.3 Equipment that works continuously, such as centrifugal pumps and suction pumps, should be equipped with backup equipment.
9.2.4 All devices should store core components and wearing parts.
9.3 Performance requirements
9.3.1 The performance of the booster pump shall meet the requirements of GB / T 5657. http://euhowblog.com/
9.3.2 The performance of microfiltration membranes shall meet the requirements of HY / T 061; the performance of ultrafiltration membranes shall meet the requirements of HY / T 112; the performance of nanofiltration membranes shall conform to the requirements of HY / T 113; the performance of reverse osmosis membranes It should meet the requirements of GB / T 19249 and HJ / T 270; the performance of the ion exchanger should meet the requirements of GB / T 50109; the performance of the electrodialyzer should meet the requirements of HY / T 034.2 and HY / T 034.3; The performance of the membrane stack should meet the requirements of HY / T 120.
9.3.3 The performance of the dosing equipment shall meet the requirements of HJ / T 369.
10 Process inspection and process control
10.1.1 The testing items, the setting of testing points and the frequency of testing shall comply with the relevant regulations of HJ 471. The online monitoring device shall comply with the relevant regulations of HJ 471.
10.1.2 The main units of desalination pretreatment, electrodialysis, electrodesalination, ultrafiltration, nanofiltration, reverse osmosis, ion exchange treatment
, evaporation or freezing should adopt automatic control.
10.1.3 The control methods and control parameters shall comply with the relevant provisions of HJ 471. http://euhowblog.com/
11 Major auxiliary works
Buildings and structures should comply with the provisions of GB 50069 and GB 50141; electrical, air-conditioning and HVAC, water supply and drainage and fire protection, roads and greening should comply with the provisions of HJ 471.
12 Occupational safety and occupational health
Labor safety management shall comply with the relevant regulations of GB 12801 and HJ 471.
13 Engineering Construction and Acceptance
13.1.1 The construction and acceptance of the project shall comply with the relevant provisions of HJ 471.
13.1.2 The performance test before acceptance shall comply with the relevant regulations of HJ 471.
14 Operation and maintenance
14.1 Operation management and water quality monitoring
14.1.1 The operating conditions of the processing facilities shall be monitored in accordance with GB 4287, DB37 / 3416.1, DB37 / 3416.2, DB37 / 3416.3, DB37 / 3416.4, DB37 / 3416.5 and HJ / T 92 standards.
14.1.2 The operation and maintenance of wastewater treatment projects shall comply with the relevant regulations of HJ 471.
14.1.3 According to the process needs of the water treatment unit, the relevant process parameters and water quality indicators during the operation should be monitored. Water quality monitoring indicators for routine treatment and their measurement shall comply with the relevant regulations of HJ 471. The water quality monitoring indicators and measurement of the desalination unit shall meet the following requirements:
a) The monitoring indicators of the desalination unit operation process include total salt content, hardness, turbidity, pH value, etc .; determine the sampling frequency according to the operating conditions, and analyze at least once a day;
b) The total salt content shall be determined in accordance with HJ / T 51; the hardness shall be determined in accordance with GB / T 7477 and GB / T 6909; the turbidity shall be determined in accordance with GB 13200.
14.1.4 The key control indicators that can be monitored online shall be monitored online and connected to the monitoring center; if an online monitoring system is installed, regular sampling shall be performed for manual inspection and comparison.
14.1.5 The frequency of analysis and testing of monitoring items should be increased in the event of commissioning, restart after shutdown, and in the event of an accident. Sampling of water quality is performed at the discharge outlet of the wastewater treatment facility and the control point selected according to the treatment process.
14.1.6 Facilities such as pretreatment and desalination treatment should be provided with on-line detection devices. The detection points are located in the controlled unit or at the entrance and exit respectively. The sampling frequency and monitoring items should be determined according to process control requirements.
14.2 Emergency measures
Emergency measures shall comply with HJ 471 and relevant regulations of national and local emergency environmental emergency management.