Polyacrylamide (PAM) is a high molecular weight polymer widely used in water treatment processes in various fields. It has a variety of molecular weights, ionicities, and structures to suit different usage scenarios and can even be customized for special scenarios. Through electrical neutralization and polymer adsorption and bridging, PAM can promote the rapid agglomeration and sedimentation of suspended particles, improving water quality. This article will delve into the specific applications and impacts of PAM in water treatment in various fields.
In domestic sewage treatment, PAM is mainly used for flocculation sedimentation and sludge dewatering. By neutralizing electrical properties and employing adsorbing bridging effects, PAM can accelerate the agglomeration of suspended solids in water to form flocs of large particles. These flocs are easy to settle and filter, thereby effectively removing impurities in the water and achieving the purpose of purifying water quality. The use of PAM can improve sewage treatment efficiency and reduce treatment costs.
In the field of papermaking, PAM is mainly used as a retention aid, filter aid, dispersant, etc. By adding PAM, the retention rate of fillers and fine fibers in the paper can be improved, reducing the consumption of raw materials, and enhancing the filterability and dehydration performance of the pulp. Additionally, PAM can serve as a non-silicon polymer stabilizer in the bleaching process, improving the whiteness and brightness of the paper.
In alcohol plant wastewater treatment, PAM is primarily used in the sludge dehydration process. For alcohol production processes with different raw materials and wastewater treatment processes, it is crucial to select cationic polyacrylamide with appropriate ionicity and molecular weight. Selection testing through experimental beaker experiments is one of the commonly used methods.
Food wastewater, with its high organic matter and suspended solids content, requires appropriate treatment methods. The traditional approach involves physical sedimentation and biochemical fermentation. However, in practical applications, polymer flocculants are often necessary for sludge dehydration and other treatment operations. Most of the flocculants used in this process are cationic polyacrylamide series products. Selecting a suitable polyacrylamide product requires considering the impact of climate change (temperature) on flocculant selection, choosing appropriate molecular weight and charge value based on the floc size required by the treatment process, and other factors. Additionally, attention should be given to issues such as process and equipment requirements and the use of flocculants.
In electronic and electroplating wastewater, PAM is mainly used as a Flocculant and precipitant. By neutralizing electrical properties and employing adsorbing bridging effects, PAM can quickly agglomerate and settle heavy metal ions in wastewater. In this process, it is generally necessary to add sulfuric acid to the wastewater to adjust the pH value to 2-3 and then add a reducing agent. In the next reaction tank, use NaOH or Ca(OH)2 to adjust the pH value to 7-8 to generate Cr(OH)3 precipitates. Then add a coagulant to precipitate and remove Cr(OH)3. Through these treatment processes, PAM helps improve the efficiency of electronic and electroplating wastewater treatment and reduce the harm of heavy metal ions to the environment.
Post time: Jun-04-2024