Amphoteric sesbania gum coagulant aid and preparation method and application method thereof

Abstract

The invention discloses an amphoteric sesbania gum coagulant aid and a preparation method and an application method thereof. The amphoteric sesbania gum coagulant aid is prepared by a series of procedures of dissolving, alkalization, anion treatment, cationization, and amphoteric treatment. The amphoteric sesbania gum coagulant aid is blended into a solution of which the concentration is 10mg / L in application, and mixed with a polymeric ferric sulfate solution of which the concentration is 200mg / L to form a combination solution; the PH value of the combination solution is controlled at 7. The amphoteric sesbania gum coagulant aid disclosed by the invention is prepared from sesbania gum by cation and anion modification, so that the water solubility is improved, the compatibility with electrolyte is improved, and the stability of the viscosity is increased. The amphoteric sesbania gum coagulant aid has the advantages of being simple in preparation method, convenient to operate, free of toxicity, good in coagulation aid effect, high in CODcr (Chemical Oxygen Demand Cr) removal rate, fast in dirty settling velocity, and high in turbidity removal rate. Practice proves that the coagulate effect can be greatly improved when the amphoteric sesbania gum coagulant aid is compounded with the polymeric ferric sulfate, the coagulation sedimentation velocity is quickened, alumen ustum is dense, and the CODcr removal rate can be up to 80%.

Description

Technical field [0001] The invention belongs to the technical field of sewage treatment, and specifically relates to a coagulation aid, in particular to an amphoteric sesame gum with non-toxicity, good coagulation aid effect, high CODcr removal rate, fast turbid sedimentation rate and high turbidity removal rate. Agent and its preparation method and application method. Background technique [0002] In sewage treatment, when the coagulant alone cannot achieve the expected effect, it is necessary to add some auxiliary agent to improve the coagulation effect. This agent is called a coagulant. Broadly speaking, any chemical agent that cannot be used as a coagulant alone in a particular water treatment process but can be used in conjunction with a coagulant to enhance or improve the effect of coagulation and flocculation can be called a coagulant aid. Coagulants can be used to adjust or improve the coagulation conditions, for example, when the alkalinity of the raw water is insuffici...

AI Technical Summary

Problems solved by technology

The coagulant aids currently used are mostly synthetic polymer coagulant aids, and polyacrylamide and its derivatives are the mainstream products in the coagulant aid market. Polyacrylamide (PAM) is a water-soluble polymer, insoluble Compared with most organic solvents, it has good flocculation. Polyacrylamide itself and its hydrolysis are not toxic. The toxicity of polyacrylamide comes from its residual monomer acrylamide (AM). Acrylamide is a neurotoxic agent, which is harmful to the nervous system. It has the effect of injury, and after poisoning, it will show symptoms such as body weakness and movement disorders. Therefore, the health departments of various countries have regulations to strictly limit the use of polyacrylamide in sewage treatment.

Therefore, people began to develop coagulant aids to replace acrylamide and its derivatives, but the effect of other coagulant aids on the market is very poor, the removal rate of CODcr is very low, the sedimentation speed of dirt is very slow and the removal rate of turbidity is also very low. Low