First, the characteristics of the electronic industry wastewater
Complex components: the electronic industry wastewater mainly from the circuit board etching, cleaning, developing, stripping and other processes, which contains heavy metal ions (such as copper, nickel, lead, cadmium, chromium, etc.), fluoride, ammonia and nitrogen, organic solvents (such as alcohols, ketones, halogenated hydrocarbons, etc.), surfactants, as well as high-concentration acids and alkalis and other pollutants, the composition of the complexity and the concentration of different.
Toxic and harmful: many heavy metal ions and organic pollutants in the electronic industry wastewater are persistent, bioaccumulative, and toxic; if not properly treated and discharged directly, they will seriously harm the ecological environment and human health.
pH value fluctuations: The electronics industry's production process uses more acid and alkali chemicals, resulting in a wide range of changes in the pH value of the wastewater, which has made wastewater treatment somewhat difficult.
Second, the electronic industry wastewater treatment process
Physicochemical treatment: First, through the grid, precipitation, air flotation, and other ways to remove suspended solids and large particles in the wastewater. For heavy metal ions, the general use of chemical precipitation or ion exchange methods, such as adding precipitants to form heavy metal hydroxide or sulfide precipitation or the use of ion exchange resin adsorption of heavy metal ions. Acid and alkali wastewater are adjusted to pH values using the neutralization method.
Biological treatment: Biological treatment technologies, such as activated sludge and biological contact oxidation, can degrade organic matter using microbial metabolism in wastewater containing organic pollutants.
Advanced oxidation technology: For some organic pollutants that are difficult to biodegrade, advanced oxidation technology such as Fenton oxidation, ozone oxidation, electrochemical oxidation, etc., can be used to convert organic pollutants into low-toxic or non-toxic small molecules and to improve the biochemistry of wastewater.
Membrane separation technology: Ultrafiltration, reverse osmosis, nanofiltration, and other membrane separation technologies can effectively remove tiny particles, colloids, and dissolved organic matter from wastewater to achieve deep purification.
Resource Recovery and Comprehensive Utilization: Due to the electronics industry, some wastewater contains precious metals, such as copper, gold, silver, etc. Electrolysis, extraction, adsorption, and other methods can be used to recover and utilize these valuable resources.
Treatment Process
Semiconductor ultrapure water system
Standard:
- International Association of Semiconductor Equipment and Materials (International Association of Semiconductor Equipment and Materials, SEMl), the latest version of its standards for SEMIF63-0918
- International Technology Roadmap for semiconductor (ITRS). The latest version of its standard is 2015 ITRS
- American Society for Testing Materials (ASTM), the latest version of its standard is ASTM D5127-13(2018).
CORE TECHNOLOGY
Process Flow
Process characteristics
- Innovative pretreatment system: realizing low chemical consumption pretreatment system;
- Special EDI system: realizing very low chemical consumption and ultra-high PPT grade silica-boron water production;
- Special silicon-boron removal resin system: realizing the requirement of 1-5PPT grade ultrapure water;
- Continuous testing system: realizing real-time system water quality monitoring;
- BIM: allow the design and construction visualization to achieve the efficient implementation of the efficiency of the site;
- Intelligent design: Intelligent modular design, setting up cloud data centers, enabling unattended operation, and early warning and preventive maintenance.
Semiconductor Wastewater Systems
CORE TECHNOLOGY
Process Flow
Process characteristics
- Innovative quality separation and recycling system: It realizes the classification of acid and alkali/organic/inorganic recyclable wastewater and realizes the system of zero discharge of wastewater in high-demand areas;
- Intelligent dosing system: to realize precise dosing, impact resistance, precise dosing in anticipation of changing trends, reducing the number of chemicals and sludge, and stabilizing the quality of water produced;
- Special defluoridation system: realizing the 1-3ppm level of effluent water quality requirement and saving 30% of operation cost;
- BIM: allow the design and construction visualization to achieve efficient implementation of the efficiency of the site;
- High-value metal recovery: special membrane lifting membrane and chelating resin to realize high-value metal recovery of wastewater;
- Grinding wastewater recycling system: Realize 90% of BG/DS/CMP wastewater recycling and realize an ultra-high wastewater recycling system.
- High concentration system: as a preconcentration of the evaporator, the salt content of the concentrated water can be up to 10%-18%, reducing the investment and operating costs of the evaporator;
- Resource recovery: recover industrial-grade salt, multi-stage membrane treatment, the real realization of zero discharge of wastewater;
- Intelligent design: intelligent modular design, forming the cloud data center to achieve unattended early warning and preventive maintenance.
Case:
Xxx Semiconductor Limited (Advanced Packaging, Zero Discharge + Ultrapure Water)
Client Profile: With the IC front-end chip manufacturing system and standards, we are committed to providing high-quality mid-range wafer manufacturing and testing services and further developing advanced 3D system integration chip business to serve global customers.
Project Profile: This includes the nitrogen and phosphorus wastewater treatment system generated in the production process, electroplating wastewater treatment, and wastewater after treatment, all of which go back to the preparation of nitrogen and phosphorus pure water system raw water and ultrapure water system. Has completed the construction of several sets of ultrapure water, water supply, and water quality once up to standard.
Water indicators: resistivity ≥ 18.2MΩ-cm, TOC ≤ 10ppb
Main process:
Pretreatment + biochemical + MBR + multi-stage membrane separation + evaporation crystallization (zero discharge)
Pre-treatment + two-stage RO + EDI + polishing fine treatment + terminal filtration (ultrapure water)
