In addition to the commonly used poly aluminum, iron, and active silica gel and their modified products, such as poly silicon aluminum (iron), phosphorus (iron). Purpose is to introduce some high charge ions in order to improve the abilities of neutralizing electric charge, introduce hydroxyl, phosphoric acid root, etc in order to increase coordination complexation ability, so as to change the flocculation effect, the possible reason is: some anionic or cationic can change the morphology and distribution of the polymer, or between two or more polymers have synergy effect.

   Polysilicic acid flocculants (PSAA) due to the preparation method is simple, wide raw material sources, low cost, is a new type of inorganic polymer flocculant, the thick oil oil field produced water treatment has better oil removal ability, therefore has a great development value and broad application prospects.

Poly ferric sulfate (PFSS) silicate flocculant, found a "highly polymerization of the silicate with metal ion can produce good coagulation effect. The metal ion to polysilicic acid, the coagulant the average molecular weight up to 2 x 105, may be partly replacing organic synthesis in the water treatment polymer flocculant.

   Phosphorus ferric chloride (PPFC), PO43 - high anion and Fe3 + strong affinity, have greater influence on the hydrolytic solution of Fe3 +, to participate in the complexation reaction of Fe3 + and bridge between the iron atoms, forming polynuclear complex; Electrical neutralization of diatomite of negatively charged colloid in water adsorption bridging role, at the same time due to the participation of PO43 - make the volume of the alum flowers, density increase, the flocculation effect increased.

   Phosphorus chloride (PPAC) is based on phosphoric acid root strength increase of polymeric aluminium (PAC), introducing the right amount of phosphate in the polymeric aluminum, by gathers the function of phosphoric acid root, make PPAC produced a new type of high charge with phosphoric acid root of polynuclear complex in the middle.

Polysilicic acid iron (PSF), it can not only well with low temperature and low water, but also has obvious superiority than ferric sulfate flocculation effect, such as less dosage, wide range of feeding, alum flowers form bulky easily settling time is short and form, can shorten the retention time of water samples in processing system, etc., thus improving the processing capacity of the system, and the basic no effect to deal with the pH of the water.