The development of filter press in printing and dyeing industry

The sludge discharged from printing and dyeing wastewater after biochemical treatment has a moisture content of approximately 99.5%. After natural settling, the concentrated sludge still has a moisture content of 90%-95%. Dewatering this sludge using an automatic filter press can remove 93%-94% of its water content, reducing its volume to 1/15 of its pre-dehydration volume. The resulting sludge cake is therefore easier to transport and dispose of. For example, a Shanghai printing and dyeing plant with a daily wastewater output of 4,000 tons produces 15 cubic meters of concentrated sludge with a moisture content of 98%. Using a 15-square-meter automatic plate and frame filter press, the dewatering process can be completed in 10 hours per day.

Technological Developments

Automation and Intelligence: Modern filter presses used in printing and dyeing wastewater treatment are typically equipped with automated control systems, enabling automated operation, reducing manual intervention, improving efficiency, and simplifying operational complexity. For example, sensors monitor real-time parameters such as pressure, liquid level, and temperature, and artificial intelligence algorithms are used to analyze and predict data, enabling automatic adjustments to equipment operating conditions. Improved Corrosion Resistance: Printing and dyeing wastewater contains high concentrations of dyes, additives, and salt, which can easily cause scaling and corrosion in traditional equipment. Fiberglass filter presses, due to their corrosion resistance, have become key equipment for printing and dyeing wastewater treatment. Their epoxy resin fiberglass anti-corrosion layer is resistant to organic solvents, and their multi-port feed design improves filtration efficiency by 30%, extending the filter cloth regeneration cycle to over 500 times.

Improved Dehydration Efficiency: Some filter presses utilize diaphragm pressing, achieving pressures of 1.6-3.0 MPa. This significantly reduces filter cake moisture content and reduces energy consumption for subsequent treatment. For example, a printing and dyeing company integrated an inclined tube sedimentation and filter pressing process, increasing wastewater reuse to 70% and saving over 2 million yuan in water costs annually.

Future Trends: With the printing and dyeing industry's increasing environmental requirements and continuous technological advancements, filter presses will evolve towards high-end, intelligent technologies. The market for specialized filter presses for the printing and dyeing industry will continue to grow, further segmenting the market to meet the personalized needs of different application scenarios and process requirements. Furthermore, energy-saving and environmentally friendly filter presses will become increasingly popular, helping the printing and dyeing industry achieve its green development goals.