At present, the application of automatic water quality samplers in online monitoring systems has been very common. According to the specific needs of the project, it is common to have a low-temperature refrigeration function, and it is rarely necessary to add a fixative. .
With the update of environmental standards for pollution sources, some regions (Jiangsu and Jiangxi) have proposed the automatic addition of preservatives to the sample bottles of DR water quality automatic samplers in order to preserve water samples for a longer period of time based on their own characteristics. According to the requirements, the pollution source measurement parameters are generally chemical oxygen demand (CODCr), ammonia nitrogen (NH3-N), total phosphorus (TP), and total nitrogen (TN). The preservative added is concentrated H2SO4, and the adding amount is generally per L. Add 0.8ml to the water sample to acidify the pH value between 1 and 2. According to HJ493-2009 "Technical Regulations on Preservation and Management of Water Quality Samples", after adding preservatives, the effective storage time of chemical oxygen demand (CODCr) is 2 days, ammonia nitrogen (NH3-N) is 24 hours, and total phosphorus (TP) is 24 hours, and total nitrogen (TN) is 7 days. At the actual work site, because the wastewater samples from sewage treatment plants and sewage discharge companies have been deeply processed, there are no volatile or easily digestible substances, and the values ??of the monitored factors are stable with minimal changes. It is generally recommended to complete the test within 2 days without adding fixative, and within 5 days after adding preservative!
The 803N water quality automatic sampler can realize the functions of collecting mixed water samples, mixing and temporarily storing mixed water samples, retaining samples exceeding the standard and alarming, refrigerated samples, automatic cleaning and emptying the mixing barrel. Automatically add fixative to extend sample storage time and protect samples according to your own needs. At the same time, it can also meet the standards of the HJ35X-2019 series and is an indispensable supporting equipment in the overall solution of the water pollution source online monitoring system!