Semi automatic Microbial Colony Detection Kit Company

Scaling, corrosion, and microbial growth are the three main problems in circulating cooling water systems. The circulating cooling water process has suitable characteristics for microbial growth, such as a temperature of 30-40 ℃, a pH of around 8.5, and sufficient nutrients for both organic and inorganic salts due to cyclic concentration. In addition, the cooling tower and cold water tank are exposed outdoors all year round, with ample sunlight and sufficient contact with the air, allowing a large amount of oxygen to dissolve into the water and absorb dust, mud, sand, and other microbial spores from the air, making it very easy for microorganisms to grow. With the increasing use of recycled water as a cooling tower makeup water source, it is expected that in the future, the biological corrosion caused by microorganisms will be greater than the scaling effect caused by hardness and alkalinity.

There are generally three types of microorganisms commonly found in circulating cooling water systems that can cause system failures: bacteria, fungi, and algae. Mud producing bacteria belonging to the bacterial class are harmful bacteria with a large number in circulating cooling water systems. Microbial sludge deteriorates water quality, causing the color of the water to darken or turn black and emitting unpleasant odors. Mud adheres to pipelines, equipment, or cooling tower walls, causing system blockages and scaling, increasing hydraulic losses, reducing heat transfer efficiency, increasing energy consumption and operating costs, and posing safety hazards to production.

Microbial slime also provides a breeding ground for anaerobic bacteria (such as sulfate reducing bacteria), iron deposition bacteria, and pathogenic bacteria (such as Legionella). For example, acid producing microorganisms produce organic acids such as acetic acid, lactic acid, oxalic acid, citric acid, and gluconic acid during their metabolism. These acids can cause changes in water quality composition and lead to metal corrosion.

At present, the commonly used methods for treating microorganisms in China include strengthening the pre-treatment of raw water, improving the quality of supplementary water, regularly alternating the use of oxidizing and non oxidizing fungicides, and ensuring the safe and stable operation of the circulating water system through the strengthening of microorganisms and their daily detection methods.

Compared to conventional methods for detecting the total number of heterotrophic bacteria,Microbial detection reagent kit for tap waterWith advantages such as on-site sampling analysis, 5-minute results, and analysis of total microorganisms (non partially cultivable microorganisms), it has been widely used in the North American and European markets and has formed a set of standards for evaluating microbial control in circulating cooling water. By regularly sampling and analyzing the ATP concentration (pg/mL) in circulating water, it can help operators to determine the degree of microbial control in real time, select the appropriate type, dosage, and dosing frequency of sterilizing agents.

What is ATP testing?

Comparison between ATP method and plate culture methodAll living cells contain ATP (adenosine triphosphate), and the concentration of ATP in microbial cells can directly reflect the concentration of microorganisms. The ATP concentration can be measured by the brightness generated by the reaction between ATP and luciferase, and the concentration of residual microorganisms and the degree of sterilization can be determined based on the results.

Case One

Altis Semiconductor's semiconductor factory in France willMicrobial detection reagent kit for tap waterAfter conducting microbiological testing on the circulating water of its 19 cooling towers, the sterilization efficiency validation results that originally took several days to obtain using the cultivation method were shortened to 10 minutes. At the same time, the company analyzed the sterilization effects of different disinfectants and compared the sterilization effects of existing silver/hydrogen peroxide and hypobromic acid, as well as hypochlorous acid/chlorine dioxide, under different cooling tower and water source conditions. It was found that the sterilization effects of hypochlorous acid/chlorine dioxide and hypobromic acid were better than the existing solutions. Therefore, it was decided to use electrolytic generation of hypochlorous acid/chlorine dioxide as a new disinfectant dosing scheme, achieving an annual savings of 6 tons of disinfectant and avoiding bromide emissions.

After conducting ATP tracking analysis on different sterilization schemes at the same location, it was found that using silver/hydrogen peroxide could not meet the sterilization requirements, while hypobromic acid could meet the sterilization requirements; When ORP is controlled to less than 500, hypochlorous acid/chlorine dioxide can also meet the sterilization requirements.