Poly ferric sulfate belongs to inorganic ferric salt coagulant, and the pH value of the product is acidic. The pH value of 1% concentration of poly ferric sulfate solution is about 2.3 in the range of 2.0-3.0. If the pH value of poly ferric sulfate is higher than 4, the product is easy to hydrolyze and precipitate will appear in water treatment. However, if the pH value of PFS is less than 2, the basicity of the product is relatively low, and a large number of alkaline regulators need to be added, which increases the cost of water treatment.

The pH value of wastewater treated by polymeric ferric sulfate has a wide application range. 4-11 can be used, and the suitable pH value is 6-9. At this time, the effect of coagulation, sedimentation, turbidity removal, decolorization and phosphorus removal is ideal. When the pH value of the wastewater changes greatly, the use effect of PFS will also be affected. When the pH value of the wastewater is strong (pH < 3), or the alkalinity is too strong (pH < 11), PFS will be inhibited in the process of hydrolysis, which can not fully hydrolyze and affect the flocculation effect.

It is usually necessary to add alkali or acid to adjust to the appropriate pH range. Polyferric sulfate (PFS) is a process of adsorption and precipitation of various pollutants by polynuclear complex in wastewater. In addition to the pH value of water body, it is also affected by wastewater temperature, hydraulic stirring speed, pollutant concentration and so on. When adding PFS in the water treatment coagulation tank, first dissolve the solid PFS product according to the concentration of 10-30%, use clean tap water to dissolve the drug, fully stir to ensure the complete dissolution of PFS, and then present a reddish brown liquid after dissolution, and then add water to dilute to the required concentration.

Industrial wastewater can also be directly added with 5-10% concentration. According to the nature of raw water, the amount of industrial wastewater can be determined by on-site commissioning after beaker test. If the product is liquid polyferric sulfate, it can be diluted to the required concentration according to the concentration of the reagent, and then put into use. In the process of water treatment, PFS is used. Attention should be paid to the hydraulic conditions and alum formation in the three stages of coagulation.

Solid polymeric ferric sulfate products need to be stored in a ventilated, dry and heat-resistant place, and transported waterproof and moisture-proof. In the process of transportation, attention should be paid to prevent heat and moisture, avoid package damage, product packaging 25kg / bag, plastic moisture-proof film, woven bag double-layer packaging, unsealed and used PFS products. Before use, attention should be paid to seal the packaging bag, empty the air in the bag, and avoid PFS atomization and hardening.