Attapulgite-based composite flocculating agent and preparation method thereof

Abstract

The invention belongs to the technical field of sewage treatment, and particularly relates to an attapulgite-based composite flocculating agent and a preparation method thereof. The preparation methodcomprises the following steps: (1) modifying attapulgite; (2) adding zinc dimethacrylate and an initiator to ethanol, performing heating refluxing, adding the modified attapulgite and hydrogenated castor oil, performing refluxing and heat insulation, centrifuging and filtering the obtained solution, washing obtained filter residues with anhydrous ethanol, and drying the washed filter residues until the weight is constant in order to obtain intercalation modified attapulgite; (3) performing surface composite modification on magnesium aluminum silicate; and (4) mixing and granulating the intercalation modified attapulgite and the composite modified magnesium aluminum silicate. Intercalation modification of the attapulgite makes the modified attapulgite better than the original attapulgite in flocculation of suspending substances in sewage; the composite modification of the surface of the magnesium aluminum silicate makes the magnesium aluminum silicate have a good flocculation effect ata lower dosage, and the mixing and granulation of the modified attapulgite and the modified magnesium aluminum silicate improve the treatment efficiency of the suspending substances in the sewage when the attapulgite-based composite flocculating agent is used to flocculate the suspending substances during sewage treatment.

Description

technical field [0001] The invention belongs to the technical field of sewage treatment, and in particular relates to a composite flocculant based on attapulgite and a preparation method thereof. Background technique [0002] Domestic sewage is the wastewater discharged from residents' daily life. The pollutants contained in it are mainly organic matter and a large number of pathogenic microorganisms. Bacteria and pathogens multiply by using organic matter in domestic sewage as nutrients, which can lead to the spread of infectious diseases. Therefore, domestic sewage must be treated before discharge. [0003] In the prior art, domestic sewage can be divided into primary treatment, secondary treatment and tertiary treatment according to its treatment degree. The primary treatment is mainly to remove the suspended solid matter in the sewage, and physical methods are commonly used. The BOD removal rate of wastewater after primary treatment is only 20%, which is still unsuitab...

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Problems solved by technology

From low-molecular to high-molecular, from single type to compound type, the general development trend of flocculants is to develop in the direction of cheap, practical, non-toxic and high-efficiency. Inorganic flocculants are cheap, but they will have adverse effects on human health and the ecological environment; Although the amount of organic polymer flocculant is small, the output of scum is small, the flocculation ability is strong, the flocs are easy to separate, and the effect of removing oil and suspended matter is good, but the residual monomer of this type of polymer has "three effects" ( Teratogenic, carcinogenic, mutagenic), thus limiting its scope of application; microbial flocculants are easy to use and have attractive application prospects because of the absence of secondary pollution. However, microbial flocculants mainly include flocculants using microbial cell wall extracts. , the current microbial flocculants are mainly used in the fields of medicine, food processing, and separation of biological products. It is inevitable that the use of them in a large number of sewage treatment technology fields will outweigh the gains, resulting in an increase in the cost of sewage treatment

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