The ChemScan Sample Sequencer was developed for plantwide monitoring of nutrient removal processes. It can be configured to measure multiple, critical control parameters including nitrate, nitrite, ammonia, phosphate and organics. The sample sequencer coordinates the operation of the sample pumps, sample filter and the ChemScan UV Analyzer system, and interfaces directly with the plant PLC.

The sequencer manages the sample flow from each sample location. One of its key features is the ability for the operator to program the order of the sampling cycle. The system is designed for continuous operation, so that a new sample line is flushing while samples are being analyzed from the prior sample line.

Each parameter at each sample location has its own calibration and sends a dedicated signal showing analysis results to the plant SCADA system. This data is then used to control aeration rates, recirculation rates and chemical feed. This helps avoid operational problems by allowing operators to make process control adjustments before limits are exceeded.