Wastewater online monitoring system, is another most common type of online monitoring system, generally set up and installed at the wastewater discharge point of the sewage enterprises. The normal operation of online equipment and data accuracy, the need for online equipment for regular testing and comparison, according to the actual situation of the equipment for debugging and calibration, there are a number of parameters, 24-hour drift can be self-provided by the standard concentration of reagents, by the day-to-day business and the operator's own operation; a part of the parameters, the accuracy of the third party on-site sampling and experiments are required to meet the requirements, the following is mainly to talk about The accuracy of the comparison and related ways.
The accuracy of the comparison is also divided into acceptance comparison and daily comparison of two ways, respectively, as follows:
Acceptance of the online comparison, (cod / ammonia nitrogen / total phosphorus / total nitrogen) will be a high standard (close to the corresponding implementation of the standard limit value of 2-3 times the standard) and low standard (close to the concentration of reagent wastewater discharge of the standard) taken to the scene, the online equipment to analyze the analysis of each specimen to do 3 times, to provide data of each specimen 3 times, (the data of each specimen 3 times), (the data of each specimen 3 times,) the data of each specimen 3 times. standard sample 3 times, (pH) only one standard sample (pH = 4.0), determination of 6 times, to provide 6 times the data; and then collect the actual water samples, according to the interval of the analytical instrument, the collection of 3 actual water samples, brought back to the laboratory, while the online equipment to determine the 3 actual water samples, (cod / ammonia nitrogen / total phosphorus / total nitrogen) each actual water samples measured 2 times to provide the results of the measurement of each water sample twice, (pH) each actual water samples measured 6 times, (pH) each actual water samples measured 6 times, (pH) each actual water samples measured 6 times. ) Each actual water sample is measured 6 times, and each actual water sample is provided with 6 measurement results; at the same time, if there is an alternative sample (when the concentration of water is lower than a certain range, the use of standard samples to replace the actual water samples), each alternative sample is measured twice, and the measurement results are provided.
Daily online comparison, (cod/ammonia/total phosphorus/total nitrogen) will be the only standard solution to take to the scene (the scene of the instrument to set the range of 50% of the standard), the online equipment to analyze the standard samples to do 1 time, to provide the data of each standard sample, (pH) there is no standard samples; and then collect the actual water samples, according to the analysis of the instrument's intervals, (cod/ammonia/total phosphorus/total nitrogen) to collect the actual water samples of 3 times, to bring back to the Laboratory, at the same time on-line equipment to determine the three actual water samples, (cod/ammonia/total phosphorus/total nitrogen) each of the actual water samples measured 1 time, to provide each water sample 1 measurement results, (pH) as long as one actual water samples, the actual water samples measured once, to provide the results of the measurement, and, at the same time, if there is a substitution of samples (when the concentration of water is lower than a certain range, the use of standard samples to replace the actual water samples), each substitution of 3 times to provide the results of the determination of the substitution. The actual water sample will be measured once and the results will be provided.
After the sampling test is completed, the data will be summarized to calculate the relative and absolute errors of the laboratory data/standard data and the data displayed by the online device, and also compare the standard requirements to determine whether it is qualified. Qualified, the online equipment normal in the cycle to continue to work, if not qualified, to analyze to find out the reasons, if the online equipment is the problem, you need to debug and calibrate as soon as possible, and then again compared until qualified before uploading data.