New environmental protection technology water-based ink wastewater treatment

Water-based ink wastewater is a significant category of pollutants within the textile dyeing and finishing industry. It has emerged as a new and typical type of wastewater in the printing and dyeing sector, characterized by high CODcr levels, intense coloration, and poor biodegradability. When released into water bodies, it poses serious threats to both the environment and human health, disrupting ecological balance. Water-based inks are primarily used in low-end printing applications such as books, magazines, corrugated paper, and other packaging industries like tobacco, winery, pharmaceuticals, cosmetics, children’s toys, and milk beverage packaging. During the production and application of these inks, cleaning processes generate wastewater. The primary sources include the washing of printing equipment, such as ink rollers, tanks, and work areas during ink changes. Water-based inks can be categorized into three types: water-soluble, alkali-soluble, and dispersible. Among them, alkali-soluble inks are currently more widely researched and applied. 1. **Water-soluble inks** typically contain materials like polyvinyl alcohol, hydroxyethyl cellulose, and polyvinyl arsenic chromone. These resins dissolve permanently in water, making the ink suitable only for non-water-contact applications. 2. **Alkali-soluble inks** use acid resins that become soluble when mixed with an alkaline solution, such as ammonium hydroxide. Once dried, the ammonia evaporates, rendering the ink insoluble in water. 3. **Dispersible inks**, also known as latex-based inks, contain fine resin particles suspended in water. They offer high-quality coatings, good adhesion, and durability but are more challenging to clean and print on. The main pollutants in water-based ink wastewater include acrylic acid-based water-soluble resins, colored cyclic organic compounds, and large molecular weight alcohol or phenyl dispersants. Acrylic resins contribute over 80% of the CODcr in the wastewater. Additionally, various pigments—both inorganic and organic—are present, along with numerous additives like stabilizers, defoamers, and preservatives. This type of wastewater is weakly alkaline, highly concentrated, intensely colored, and difficult to degrade, making its treatment particularly challenging. Several treatment methods are commonly used: 1. **Adsorption**: This involves using solid materials to attract and bind contaminants from the wastewater. Common techniques include air flotation, ultrafiltration, and reverse osmosis. Air flotation uses bubbles to lift suspended particles, while ultrafiltration separates molecules based on size. Reverse osmosis applies pressure to remove dissolved substances. 2. **Chemical Treatment**: Methods like photocatalytic oxidation and redox reactions are effective in breaking down complex organic compounds. Iron-carbon micro-electrolysis is another technique that enhances removal through reduction, oxidation, and coagulation. 3. **Biological Treatment**: Processes such as the Sequential Batch Reactor (SBR) and hydrolysis-acidification are widely used. SBR offers flexibility, stability, and efficient removal of contaminants. Hydrolysis-acidification improves the biodegradability of wastewater by converting complex organics into simpler forms, facilitating further biological treatment. These methods, when combined, provide a comprehensive approach to managing and treating water-based ink wastewater effectively and sustainably.

Dining Chair

Fashion Swivel Dining Chair,Traditional Hot Dining Chair,180 degree rotating chair

Wings Meuble , https://www.wingsfurniture.com