Shaoxing County, Zhejiang Province: Printing and Dyeing Enterprises Leverage Membrane Emission Reduction

Materialization and biochemical treatment are widely used in the printing and dyeing enterprises of Shaoxing County. The average processing cost per ton is between 1.5 yuan and 2 yuan. The same treatment of a ton of printing and dyeing wastewater, the cost of membrane processing technology is as high as 4.6 yuan. The Shaoxing printing and dyeing company operators, who have always been known for their savvy, are now happy to do this “loss-making business.” They have launched the printing and dyeing wastewater membrane treatment technology project and become a new bright spot in the industry.

Membrane technology is highly sought after in the "Shengxin Printing and Dyeing" of the Binhai Industrial Zone. Except for being busy in the workshop, the construction personnel are stepping up to install new equipment on the open space of more than 1,000 square meters. “This is the new reclaimed water reuse transformation technology – membrane treatment technology.” The operator of Shengxin Printing and Dyeing Company stated that the whole set of equipment is expected to be put into use by the end of August.

In the three-month period, five dyeing and dyeing enterprises, such as “Shumeite” and “Bailiheng”, signed the membrane processing technology cooperation agreement with the Ningbo Branch of the Arms Technology Research Institute. “Shaoxing printing and dyeing companies are very interested in the membrane treatment technology and the cooperation approach of 'third party' management. Apart from these five companies, there are many companies that have taken the initiative to contact us, consult and negotiate.” Weapon Technology Research Institute Ningbo Branch Zhou Yusong revealed that due to the dramatic increase in business in Shaoxing, they had already rented office space in the Binhai Industrial Zone and were ready to set up offices to meet business development needs.

In addition to cooperation with the Ningbo Research Institute of the Arm Industry Research Institute, many printing and dyeing companies have also introduced foreign advanced membrane processing technologies. For example, Zhiren Printing and Dyeing invested 8 million yuan to expand and transform the printing and dyeing wastewater treatment system and the deepwater reuse treatment. The US company Dow reverse osmosis membrane technology is used and it is planned to be put into use in September.

Efforts to reduce emissions and double effect Why are so many printing and dyeing companies fond of membrane technology? "After 3,000 tons of pre-treated waste water passed through the membrane, 2,000 tons became clean water directly." Zhang Guohua, the operator of Schmidt Printing and Dyeing, went to Suzhou and Ningbo to finalize the use of membrane treatment technology. He told the author that this technology saves water and meets the requirements of energy saving and emission reduction. For enterprises, this economic account “makes no profit”.

Taking the wastewater membrane treatment technology project of “Shengxin Printing and Dyeing” currently being launched as an example, the COD concentration in the clean water after treatment is reduced to less than 50mg/L, while the COD concentration in the river water reaches about 100mg/L, and it can be completely reused to the enterprise. Industrial water. Calculated at the industrial water price of 1.15 yuan per ton, the average wastewater discharge cost after pretreatment is more than 2.8 yuan per ton. Without considering management costs such as labor, the cost of 1 ton of water is definitely higher than 4 yuan, and the membrane treatment technology not only allows the wastewater to be discharged. With a reduction of 2/3, the effectiveness of water saving and emission reduction is obvious. For this purpose, the "Shengxin Printing and Dyeing" project launched the second-stage membrane processing technology. By then, the company's emissions will be greatly reduced to achieve energy-saving emission reduction targets.

Emission reduction is a driving force. “In addition to significant reductions in water and water savings, the pressure of environmental protection and emission reduction is also one of the driving forces for printing and dyeing companies to actively seek waste water treatment upgrades.” The responsible person of the County Environmental Protection Bureau said. Since last year, Shaoxing County has adopted a series of important measures to control pollution by using an iron wrist, such as the implementation of special clean-up projects for the printing and dyeing chemical industry construction projects, and the “last phase-out” system in which dyeing and dyeing enterprises enter the control of sewage. This year, Shaoxing County has further emphasized the "sweeping spell" in the printing and dyeing enterprises' sewage exceeding the standard, that is, the last row of pollution detection is eliminated at the end of every three days.

Under the severe pressure of reducing emissions, printing and dyeing enterprises in Shaoxing County actively seek out ways to actively upgrade wastewater treatment technologies, achieve energy conservation and emission reduction, and ease environmental pressures. "Membrane treatment technology will play a decisive role in achieving emission reduction in the printing and dyeing industry of Shaoxing County and even the whole county," said the person in the industry.