Coagulation and precipitation integration equipment

Sedimentation tank is a kind of structure used to remove suspended solids from water by sedimentation. Sedimentation tanks are widely used in wastewater treatment. According to the direction of water flow in the pool, it can be divided into three kinds: horizontal flow, vertical flow and radial flow.

Horizontal sedimentation tank

It consists of three parts: inlet, outlet, water flow and sludge hopper. The flat-flow sedimentation tank has the advantages of simple structure, good settling effect, stable working performance and wide use. The efficiency of sedimentation tank can be improved by adding a mud scraper or using mechanical removal of heavy sediment.

Vertical sedimentation tank

The pool body plane is round or square. The wastewater is discharged from the inlet pipe located in the center of the sedimentation tank from top to bottom into the pool. The inlet water is provided with an umbrella baffle under the outlet to make the wastewater evenly distributed in the pool and then slowly rise along the entire section of the pool. The suspended matter settles into the conical sludge hopper at the bottom of the pool under the action of gravity, and the clarified water is discharged from the overflow weir around the upper end of the pool. Scum tanks and baffles can also be set up in front of the overflow weir to ensure the quality of the effluent. The vertical flow sedimentation tank covers a small area, has a large depth and a cone bottom, and is widely used in many industrial wastewater treatment processes.

Radial sedimentation tank

The pool body plane is mostly round, but also square. The diameter is large and the depth is small, the diameter is 20 to 100 meters, the water depth in the center of the pool is not more than 4 meters, and the water depth around the pool is not less than 1.5 meters. The waste water enters the pool from the center of the pool and flows slowly around the pool along the radius direction. The suspended matter settles in the flow, and enters the sludge hopper along the slope of the bottom of the pool, and the clarified water overflows from the circumference of the pool into the outlet channel. Generally built into steel concrete structure.

New sedimentation tank

A new type of inclined plate or inclined tube sedimentation tank has been designed in recent years. The main thing is to add a inclined plate or inclined pipe in the pool, which can greatly improve the precipitation efficiency, shorten the precipitation time, and reduce the sedimentation tank volume. However, the inclined plate and inclined pipe are easy to scale, long biofilm, scum, heavy maintenance workload, and low life of pipes and plates. Also being studied and tested are the peripheral influent sedimentation tank, the return distribution water sedimentation tank and the intermediate drainage sedimentation tank.

Sedimentation tanks are used for a variety of purposes. For example, the primary sedimentation tank in front of the aeration tank can reduce the suspended matter content in sewage and reduce the biological treatment load. The secondary sedimentation tank after the aeration tank can intercept the activated sludge. In addition, there is a chemical sedimentation tank set up after secondary treatment, that is, coagulant is added to the sedimentation tank to improve the removal efficiency of organic matter that is difficult to biodegrade, substances that can be oxidized and color-producing substances.

Equipment characteristics

1, simple structure, no wearing parts, durable, reduce maintenance. 2, stable operation, easy to operate. 3, less power, save energy. 4, occupying a province, less investment, fast, high efficiency. 5 Short residence time, high precipitation effect, high treatment efficiency, low aeration intensity, no need for sludge reflux.

Scope of use

1, electroplating wastewater containing a variety of metal ions of mixed wastewater, chromium, copper, iron, zinc, nickel and other removal rates are more than 90%, the general electroplating wastewater after treatment can meet the discharge standards.

2, coal mine, mineral processing wastewater can make turbidity from 500-1500 mg/l to 5 mg/L.

3, dyeing, dyeing and other wastewater chroma removal rate 70-90%, COD removal 50-70%.

4, tannery, food and other industries wastewater removal of a large number of organic matter, COD removal rate of 50-80%, impurity solid removal rate of more than 90%.

5, the COD removal rate of chemical wastewater 60-70%, chroma removal 60-90%, suspended matter up to the discharge standard.