Production of heavy metal capture agents using coagulants

Production of coagulantsSelection rules:

How to choose coagulants in wastewater treatment depends on the characteristics of the specific industry's wastewater, as well as at which stage the flocculant is added and for what purpose. When selecting inorganic flocculants, it is generally necessary to consider the composition and pH of the wastewater, and then choose a suitable one (iron salt, aluminum salt or iron aluminum salt, silicon aluminum salt, silicon iron salt, etc.).

When choosing organic flocculants (such as polyacrylamide PAM), the main consideration is whether to use anionic polyacrylamide, cationic polyacrylamide, or nonionic polyacrylamide. Anionic polyacrylamide is generally classified into weak negative, medium negative, and strong negative based on its degree of hydrolysis.

The selection of cations is generally used in sludge dewatering, and the selection of cationic polyacrylamide is very important. Strong cationic polyacrylamide is generally used in urban sewage treatment plants, weak cations are generally selected for sludge dewatering in paper and printing and dyeing plants, and strong cations are generally selected for pharmaceutical wastewater.

Each type of wastewater has its own characteristics, and non-ionic polyacrylamide is mainly used under weakly acidic conditions. Printing and dyeing factories use non-ionic PAM more often.

The selection of all these flocculants needs to be determined based on experiments. In the experiment, the approximate dosage is first determined, the flocculation and sedimentation rate is observed, the processing cost is calculated, and an economical and applicable flocculant is selected.

By analyzing the classification of coagulants based on their charged types, charge density, molecular weight, and molecular structure, we can gain a better understanding of their general situation and the application of various coagulants. This has led to a clearer understanding of the selection of sewage coagulants.

Application:

1. Urban sewage

The efficient mixed microbial community with flocculation and degradation functions separated from urban domestic sewage can be used to treat domestic sewage, and the removal rate of COD and BOD in sewage can reach 100%.

2. Building materials wastewater

The former mainly contains more clay particles, while the latter contains a considerable amount of glaze in addition to clay particles. After adding NOC-1 for 5 minutes, the turbidity of embryo wastewater decreased from 1.4 to 0.043; The turbidity of glaze wastewater decreased from 17.2 to 0.35; The turbidity removal rates were 96.6% and 97.9%, respectively, and almost transparent supernatant was obtained. The wastewater from the tile factory was treated with a flocculant produced by Rhodococcus pyogenes, and the treated supernatant was almost transparent.

3. Other applications

Due to the safe and non-toxic characteristics of microbial flocculants, they have gradually been adopted in the treatment of food wastewater and achieved satisfactory results. In addition, microbial flocculants can be widely used in various treatment processes such as urban sewage, hospital sewage, petrochemical wastewater, papermaking waste liquid, pharmaceutical wastewater, etc.

The high efficiency and residual amount will no longer cause secondary pollution, which is an important direction for the future research and development of flocculants. Safe, non-toxic, and efficient microbial flocculants have a great trend of replacing traditional flocculants.

Production of coagulantsHandling and Storage:

1. Avoid splashing the medication into the eyes. If in contact with the medication, immediately rinse the affected area with plenty of water.

2. Store paint coagulants in a cool and shady place, away from direct sunlight.

3. Avoid using empty buckets to hold drinking water and do not store it in alloys made of aluminum, iron, or copper.