Acid alkali resistant sedimentation tank for printing and dyeing wastewater

Disadvantages of acid and alkali resistant sedimentation tanks for printing and dyeing wastewater

Limited processing efficiency

The composition of printing and dyeing wastewater is complex (including dyes, auxiliaries, etc.), and it is difficult to remove soluble pollutants by precipitation alone. Therefore, oxidation, biological treatment and other processes need to be combined. For example, a printing and dyeing enterprise in Zhejiang Province adopts a combination process of "physical and chemical pretreatment+biochemical treatment+deep treatment" to achieve COD compliance in the effluent.

High operating costs

Continuous addition of acid-base neutralizing agents (such as sulfuric acid, *) is required to adjust the pH, and the sedimentation tank needs to be regularly drained, increasing the cost of chemicals and labor. The operating cost of ozone coagulation precipitation technology is 1.8-2.2 yuan/ton of water, which is higher than traditional processes.

Secondary pollution risk

The neutralization process may produce toxic gases such as hydrogen sulfide, and improper disposal of sludge can easily cause secondary pollution of heavy metals or dyes. Heavy metal capture agents can reduce sludge volume by 30% -50%, but traditional sedimentation methods still have this problem.

Poor adaptability

When the water quality fluctuates greatly (such as when the COD of dye concentrate reaches tens of thousands), traditional sedimentation tanks are prone to overload and require additional pretreatment. For example, a textile park in Jiangsu Province adopts a combination process of "physical and chemical pretreatment+ozone oxidation+biological treatment" to cope with water quality fluctuations.

Technical limitations

Acid alkali resistant sedimentation tank for printing and dyeing wastewaterThe removal effect of chromaticity and recalcitrant organic matter is limited. The color removal rate of ozone coagulation precipitation technology is over 90%, while the traditional precipitation method is only 50% -70%

Advantages of acid and alkali resistant sedimentation tank

Efficient sedimentation: The inclined plate/inclined tube design can shorten the sedimentation time and improve the removal rate of suspended solids (reaching over 95%).

Strong corrosion resistance: made of materials such as PP and fiberglass, suitable for high acidity and alkalinity environments (pH 8-12) in printing and dyeing wastewater.

Flexible structure: Supports customized design (such as size and shape) to meet different site requirements.

Economy: Some models are priced as low as 6690 yuan, suitable for small and medium-sized processing.