When the plate and frame filter press desludge, you can choose a variety of agents, the following are some common agents and their characteristics:

A, inorganic pharmaceutical

Polyaluminum chloride (PAC)

Advantages: high efficiency, stability, strong adaptability, a variety of sludge has a good dewatering effect.

Note: It is necessary to control the appropriate dosage to avoid excessive clogging of the equipment.

Polyferric sulfate (PFS)

Advantages: decolorization, deodorization effect is good, oily sludge has a certain treatment effect.

Note: It is also necessary to control the dosage and pay attention to its possible corrosion on the equipment.

Ferric chloride (FeCl₃)

Advantages: low price, high salinity sludge has a certain adaptability.

Note: When using, it is necessary to consider its corrosiveness to the equipment and the corrosion problem that may occur when burning the sludge cake.

Ferrous sulfate (FeSO₄)

Advantages: As a reducing agent, it has good treatment effect on some specific sludge.

Note: It should be used in combination with other agents to improve the efficiency of dehydration.

Two, organic polymer pharmaceutical

Acrylamide (PAM)

Advantages: Has a good flocculation effect, can make the sludge quickly gathered into large particles, easy to filter.

Note: The appropriate ionic type (cationic, anion or zwitterionic) should be selected according to the sludge properties, and the appropriate pH value and concentration should be controlled.

PVA

Advantages: As a surfactant, it can improve the dewatering performance of sludge.

Note: The price is relatively high, and the cost effectiveness should be considered comprehensively.

Three. Other drugs

Sludge enhancer

Advantages: The new sludge dewatering agent can reduce the moisture in the mud cake to a lower level and improve the efficiency of mud pressing.

Note: It is necessary to conduct selection tests according to the properties of sludge to determine the best dosage and use effect.

IV. Principle of drug selection

Selection according to sludge properties: different sludge properties are suitable for the use of different dewatering agents. For example, sludge with high organic content is suitable for inorganic agents (such as polyaluminum chloride, polyferric sulfate, etc.); The sludge with higher salt content may be more suitable for the use of salt agents such as ferric chloride.

Control the concentration of the agent: the higher the concentration of the agent, the better the dehydration effect, but too high concentration may lead to equipment blockage, corrosion and other problems. Therefore, it is necessary to determine the appropriate drug concentration based on laboratory test data or empirical values.

Select the appropriate dosing method: continuous dosing can maintain a certain drug effect and improve the dehydration effect; Intermittent dosing may lead to reduced efficacy. Select the appropriate dosing mode according to the actual situation.

In summary, when the plate and frame filter press desludge, the appropriate agent should be selected according to the characteristics of the sludge, the characteristics of the agent, the equipment conditions and the treatment cost. At the same time, it is also necessary to pay attention to controlling factors such as the concentration of the agent, the way of dosing and the degree of mixing with sewage to ensure the best dehydration effect.