An Established On-line Nutrient Analysis/Monitoring Technology

Mohamed Y. Z. Abouleish, Robert H. Clifford, and Dan L. Davis

Wastewater and water utilities will soon be required to control the nutrient discharge into the environment. In the meantime, permits will be issued to wastewater treatment and water utilities that regulate nutrient levels. The recommended discharge goals currently followed will eventually become required standards. In addition, to achieve maximum efficiency, utilities will have to find an alternative to the manual techniques that are currently being employed.

In order to reduce the cost and labor involved with the sampling and treatment of nutrient levels, water and wastewater utilities have reduced the monitoring process to biweekly rather than hourly. Reduction in the frequency of analysis/monitoring means that the discharge is either over-treated or under-treated due to a lack of information. Under-treatment means more nutrients are discharged, while over-treatment means more carcinogenic chemicals are discharged -- both situations have a drastic affect on all aspects of the environment. In addition, alternative methods of nutrient analysis are being sought in order to avoid the variable results that are often experienced with the manual techniques.

Shimadzu's introduction of the On-line TNPC-4110C analyzer for Total Nitrogen (TN), Total Phosphorus (TP), and Total Organic Carbon (TOC) analysis, demonstrated to the industrial arena, is the latest technology in nutrients analysis. The TN and TP analyzer has the capability of automatically sampling, treating (physically and chemically), digesting, and analyzing the samples. As a result, maximum efficiency is achieved for utilities through reduction of the involved labor, time, and cost. Most importantly, the analyzer also provides a system that facilitates adjusting the treatment of the discharge, resulting in a safer and better environment.

The Shimadzu TNPC-4110C analyzer was installed at Little Patuxent Water Reclamation Plant, operated by Howard County Bureau of Utilities in Columbia, Md. The Shimadzu analyzer was easily installed at the influent lines. Prior to the installation, the plant examined the influent on a biweekly basis to reduce the labor and cost. This meant that less information was obtained regarding the nutrient levels, affecting the treatment of the discharge. After the installation of the nutrient analyzer, the frequency of analysis was increased from biweekly to hourly, as no labor is involved in the whole process.

A better monitoring system with increased frequency of analysis ensures a faster response, as well as more effective treatment that can be adjusted according to the level of the nutrients. The process with the Shimadzu analyzer is easy and reliable, and can analyze/monitor more than one stream (or pipeline). This enabled the customer to monitor nutrients and adjust the treatment at different points within the plant, both after the biological nutrient reactors and clarifiers, and before the effluent discharge.