Polyaluminium chloride is an important water treatment agent in the field of water treatment. It is used for coagulation and sedimentation in the water purification process to remove suspended matter, colloids and other impurities in the water. Its content refers to the mass fraction of Al2O3 (aluminium oxide) in polyaluminium chloride, and the different content directly affects the role and efficacy of polyaluminium chloride.

Definition and classification of polyaluminium chloride content

The content of polyaluminium chloride usually refers to its alumina (AL2O3) content. According to the different alumina contents, polyaluminium chloride products can be divided into three types: low content, medium content and high content. The alumina content of low-content products is generally below 30%, the alumina content of medium-content products is between 30%-35%, and the alumina content of high-content products is as high as 35-40% or more. Its different contents not only reflect the purity of polyaluminium chloride, but also determine its function and application range in water treatment.

Effect of Polyaluminium Chloride Content on the Function and Efficacy of Water Treatment

The main role of polyaluminium chloride in water treatment is to act as a flocculant. It condenses suspended matter, colloids and other impurities in water into larger particles through adsorption and bridging, making it easier to precipitate and filter. The content has a direct impact on the water purification effect and efficacy of polyaluminium chloride.

1. Low content polyaluminium chloride

Due to the low content of aluminum oxide, its water purification performance is relatively weak, but low-content products are suitable for treating industrial wastewater with high turbidity, because it has good dispersibility in water and can quickly form a large number of tiny flocs, thereby effectively adsorbing and removing impurities in the water; in addition, low-content polyaluminium chloride has a low price, which is more economical and practical for some occasions where the treatment efficiency is not high.

2. High content polyaluminium chloride

Polyaluminium chloride with high alumina content has stronger water purification ability and can quickly form large and compact flocs, thereby effectively removing impurities such as suspended matter and colloids in the water. It is suitable for occasions with high requirements on water quality, such as water plants and industrial water treatment. However, the price of high-content polyaluminium chloride is high, so the choice needs to be weighed according to the actual situation.

The influence of polyaluminium chloride content on its use effect

1. Coagulation effect

A high content of polyaluminium chloride means a high concentration of aluminium oxide, which can provide stronger electrical neutralisation and bridging effects, thereby more effectively removing suspended particles and colloidal substances in the water and improving the clarity of the water. Therefore, when efficient coagulation treatment is required, people tend to choose a high content of polyaluminium chloride.

2. Solubility and stability

The solubility of high-content polyaluminium chloride is slightly worse than that of low-content products, because high concentration of aluminum salt may make the solution more likely to form coarse flocs, affecting the dispersion and use efficiency of the agent; in addition, the storage stability of high-content polyaluminium chloride may also be worse than that of low-content products, and better storage conditions are required to prevent crystallization or precipitation.

3. Economical

From an economic perspective, the content of polyaluminium chloride will also affect its cost-effectiveness. Although high-content polyaluminium chloride has stronger coagulation efficiency per unit mass, its price is usually higher, so users need to balance and choose appropriate products based on actual processing needs and cost budget.

The relationship between the content of polyaluminium chloride and its application areas

Polyaluminium chloride has a wide range of applications, including drinking water, industrial water, oilfield reinjection water, circulating cooling water, etc. Different fields have different requirements for the content of polyaluminium chloride.

1. Drinking water treatment

For drinking water treatment, it is necessary to choose high-content or medium-content polyaluminium chloride products. This is because drinking water has very high requirements on water quality. It is necessary to ensure that harmful substances in the water are completely removed, and at the same time, no harmful substances are introduced. High-content and medium-content products have good dispersion in water and can form a large number of tiny flocs, thereby effectively removing impurities and harmful substances in the water.

2. Industrial water treatment

For industrial water treatment, you can choose polyaluminium chloride products with different contents according to the specific conditions of water quality and treatment requirements. Generally speaking, for industrial wastewater with high turbidity, you can choose low-content products; while for industrial water with low turbidity, you need to choose high-content products to achieve better purification effect.

3. Oilfield reinjection water and circulating cooling water treatment

These fields also have very high requirements for water quality, and need to select high-content polyaluminium chloride products to ensure the stability and safety of water quality. This is because high-content products can quickly form large and compact flocs, thereby effectively removing impurities such as suspended matter and colloids in the water, ensuring the clarity and stability of water quality.