Polyaluminum chloride (PAC), as a common water purification agent, plays an important role in the Water Treatment Chemicals process. However, in order to ensure the best purification effect of water quality, it is important to determine the dosage of PAC reasonably. This article details how to determine the appropriate PAC dosage.
First, small test dissolve PAC to preliminarily determine the dosage range
Before using PAC for water treatment, a small test is first needed to determine the initial dosage range. The purpose of the pilot test is to observe the effect of water purification under different dosages by simulating the actual treatment process, so as to find the initial estimate of the best dosages.
Configuration of small test solution:
In order to facilitate the calculation, the configuration of the small test solution is usually carried out according to the weight ratio (W/W), and it is recommended to configure the concentration of 1%-3%. For example, take 3g PAC solid and put it into a clean 200ml container, add about 50ml water to dissolve it, then dilute it to 100ml, and shake well. It should be noted that when the turbidity of raw water is low, the dosage may be very small, and the dissolution concentration should be appropriately reduced to improve the accuracy.
Pilot experiment:
Take a certain amount of raw water (such as 1000ml) and titrate according to the proportion of small test solution. By observing the alum flowers and precipitation in the water after drip adding, the initial determination of PAC dosage was made. For example, if there are obvious alum flowers and precipitation in the raw water after dropping 10ml of the small test solution (1%), then it can be preliminarily estimated that about 0.1g PAC is required for 1000ml of raw water.
Second, on the machine operation to adjust the PAC dosage ratio
After the completion of the pilot test, it is necessary to apply the PAC dosage ratio to the actual processing system according to the pilot test results. When the machine is running, the dosage ratio of PAC should be adjusted according to the weight ratio of solid PAC and water, and the general recommendation is between 1:9 and 1:15. If it is liquid PAC, it is recommended to use a ratio of 1:2 to 1:5 for mixed dissolution.
It should be noted that the concentration of PAC solution has a significant effect on its dosing effect. When the alumina content is less than 1%, the solution is easy to hydrolyze, resulting in a decrease in purification effect. When the concentration is too high, it is not easy to evenly add, and it will also affect the purification effect. Therefore, when running on the machine, you should pay close attention to the concentration change of the solution and adjust it in time.
3. Observe the precipitation effect and adjust the dosage
In the process of dosing on the machine, it is necessary to closely observe the precipitation effect in the sedimentation tank, and adjust the dosage of PAC according to the actual situation. If there are few alum flowers and large residual turbidity in the sedimentation tank, it indicates that the dosage is insufficient. If the alum flower is too large and upturned, the residual turbidity is high, it indicates that the dosage is too large. At this time, the dosage of PAC should be adjusted in time to achieve the best purification effect.
Four, multiple experiments to determine the best dosage
Since water quality and PAC performance may vary over time and with environmental conditions, it is recommended that multiple experiments be performed to determine the optimal dosage of PAC. In the course of the experiment, the best dosage can be selected by observing the precipitation rate and the dosage of the drug used. At the same time, it is also necessary to convert the experimental results into the daily dosage of the drug consumption of the unit of use, so as to facilitate the subsequent practical application.
V. Summary
Determining the appropriate PAC dosage is a process that takes into account many factors. The optimal dosage can be gradually approximated by small test dissolution of PAC, adjustment of dosage ratio by running on the machine, adjustment of dosage by observing precipitation effect and determination of optimal dosage by several experiments. In practical applications, it is also necessary to flexibly adjust according to the actual situation of the site to ensure the best purification effect of water quality.
Focus on water treatment, just for a healthy world!
Henan Hongze Environmental Protection Technology Co.. is a professional enterprise engaged in the development, production and sales of polymer flocculants. The main products are "green water clean" brand polyaluminum chloride,
Polymerized Ferrous Sulfate，Ferric Chloride， polyferric sulfate and other water purifiers. With an annual output of 10,000 tons, the products are sold all over the country, and actively explore the international market. The company will continue to uphold the business philosophy of "integrity, innovation and win-win", provide customers with quality products and services, and make due contributions to the society.
Henan Hongze Environmental Protection Technology Co., Ltd