1. Hydrolysis and flocculation mechanism of Laboratory Chemical Reagent Aluminum Sulfate
Laboratory Chemical Reagent Aluminum Sulfate will undergo hydrolysis in water, and its hydrolysis process is relatively complex and proceeds in steps. First, Laboratory Chemical Reagent Aluminum Sulfate ionizes aluminum ions (Al³⁺), which combine with water molecules in water to form hydrated aluminum ions [Al(H₂O)₆]³⁺. As the hydrolysis reaction proceeds, the hydrated aluminum ions will gradually lose protons (H⁺) to form a series of hydrolysis products, such as mononuclear hydroxyaluminum ions [Al(OH)(H₂O)₅]²⁺, [Al(OH)₂(H₂O)₄]⁺, etc., as well as polynuclear hydroxyaluminum complexes. These hydrolysis products have a high positive charge and can attract negatively charged colloidal impurities (such as clay particles, organic colloids, etc.) in water through electrical neutralization, so that the charge of the colloidal particles is neutralized and loses stability, which is the so-called destabilization. At the same time, the aluminum hydroxide colloid produced by hydrolysis has a huge specific surface area and adsorption capacity, which can aggregate many destabilized tiny colloidal particles together through adsorption bridging to form larger floc particles, so that they can be separated from water in the subsequent precipitation or filtration process to achieve the purpose of purifying water quality.
2. Water quality factors affecting the effect of Laboratory Chemical Reagent Aluminum Sulfate
The different characteristics of water quality have a significant impact on the purification effect of Laboratory Chemical Reagent Aluminum Sulfate. The pH value of water is one of the key factors. In different pH ranges, the types and forms of hydrolysis products of Laboratory Chemical Reagent Aluminum Sulfate are different, so its flocculation effect is also different. Generally speaking, within the pH range of 6-8, Laboratory Chemical Reagent Aluminum Sulfate can form more effective flocculation components, and the flocculation effect is better at this time; when the pH value is too high or too low, the form of the hydrolysis product may be unfavorable for flocculation, and it may even dissolve again, reducing the purification effect. In addition, factors such as the content of dissolved organic matter, hardness, and temperature in water will also affect the effect of Laboratory Chemical Reagent Aluminum Sulfate. High levels of dissolved organic matter may react with aluminum ions to form a complex, affecting its hydrolysis and flocculation process; when the hardness of water is high, it may react with Laboratory Chemical Reagent Aluminum Sulfate to form precipitation, consuming part of the agent; low water temperature will slow down the hydrolysis reaction rate and also have an adverse effect on the flocculation effect.
3. Experimental method for determining the optimal dosage of Laboratory Chemical Reagent Aluminum Sulfate
A series of experiments are usually required to determine the optimal dosage of Laboratory Chemical Reagent Aluminum Sulfate in a specific water quality. First, a beaker stirring experiment can be used. Under the same water quality conditions, different Laboratory Chemical Reagent Aluminum Sulfate dosage gradients can be set, and stirring can be performed at the same stirring speed and time, and then the formation of flocs, sedimentation rate, and clarity of the supernatant can be observed. Generally speaking, with the increase of the dosage of Laboratory Chemical Reagent Aluminum Sulfate, the formation of flocs will gradually improve, and the turbidity of the supernatant will gradually decrease. However, when the dosage exceeds a certain limit, there may be a counter-effect, such as the redispersion of flocs and the increase of turbidity of the supernatant. This is because excessive aluminum ions can cause the colloidal particles to stabilize again or form secondary colloids. By comparing and analyzing the experimental results under different dosages, the dosage that achieves the best flocculation effect and is economically reasonable is the optimal dosage. In addition, the optimal dosage can be comprehensively determined in combination with some water quality monitoring indicators, such as residual aluminum ion concentration, chemical oxygen demand (COD) removal rate, turbidity removal rate, etc. In practical applications, it is also necessary to consider factors such as the treatment scale, treatment process and operating cost of the water plant to further optimize and adjust the optimal dosage.
4. Application and dosage adjustment of Laboratory Chemical Reagent Aluminum Sulfate in different water treatment processes
In different water treatment processes, the application method and optimal dosage of Laboratory Chemical Reagent Aluminum Sulfate are also different. In conventional coagulation and sedimentation processes, Laboratory Chemical Reagent Aluminum Sulfate is usually added in the rapid stirring stage so that it can be quickly mixed with the raw water and undergo hydrolysis and flocculation reactions. Its optimal dosage is mainly determined by the above experimental methods based on the water quality characteristics of the raw water, generally ranging from a few milligrams to tens of milligrams per liter of water. In some deep treatment processes, such as those combined with activated carbon adsorption or membrane filtration, the role of Laboratory Chemical Reagent Aluminum Sulfate is not only to remove colloidal impurities, but may also work in synergy with other processes, such as reducing the load of activated carbon or preventing membrane pollution through flocculation. In this case, the dosage of Laboratory Chemical Reagent Aluminum Sulfate may need to be appropriately adjusted according to the requirements of the subsequent process. For example, when combined with membrane filtration, in order to prevent membrane fouling, it may be necessary to more accurately control the dosage of Laboratory Chemical Reagent Aluminum Sulfate to ensure that the flocs formed are of moderate size, which can effectively remove pollutants without clogging the membrane. In addition, when treating different types of sewage (such as domestic sewage, industrial wastewater, etc.), due to the complexity and diversity of sewage components, the optimal dosage of Laboratory Chemical Reagent Aluminum Sulfate also needs to be adjusted according to the specific sewage quality.
