Research on Microbial Pollution of Low Concentration Organic Acids Reclaimed Water during Storage

For the study on microbial contamination of reclaimed water from reverse osmosis process during storage, multiple controlled experiments were designed to simulate actual storage conditions and three influencing factors (storage materials, time and concentration of organic acids) which had an effect on the growth of microorganisms were investigated. The results showed that the stainless steel material was superior to PVC and glass material, but different materials of storage containers didn’t make a big difference in microorganism growth. In 30 days, all the total numbers of bacteria in three container materials were under 100cfu/mL which reached the Chinese Pharmacopoeia standards for purified water and also there is no clear law between organic acids concentration and microbial growth. Analyzed by DNA sequencing and checked by microscopic and electron microscopy, the pollution bacteria was identified as Bacillus. Bacteriostatic test results showed that the concentration 0-1000 mg/L of acetic acid had no significant inhibitory effect on the growth of Bacillus.