Analysing phosphorous in water and wastewater applications.

The Liquiline System CA80PH orthophosphate analyser for monitoring water treatment processes has been launched by Endress+Hauser. The CA80PH is available in four measuring ranges.  Two use the standard molybdenum (blue method; DIN EN 1189) for low range measurement down to 50ug/l and two use the molybdate vanadate method (yellow method) for high range measurements up to 50 mg/L.  The analyser can be configured with one or two channels and can be ordered without a cabinet or with the choice of an ASA plastic or a standalone ASA-PC steel coated housing

The CA80PH automatically obtains a water sample from the process, filters it, adds the reagent, measures the intensity, and then cleans the sampling system with compressed air or water in preparation for the next test. Samples and analyses can be taken as often as necessary. A typical sample analysis takes 8 to 11 minutes depending on the method used.

In addition to the unique chemical manager which reduces chemical consumption by a factor of 8, the analyser can be fitted with a smart, energy-efficient cooling module for the reagents. Thanks to the very low rate of reagent consumption and its extended shelf life, reagents can last for up to 12 weeks depending on the concentration.

To comply with regulations for preventing release of excess orthophosphate, water resource recovery facilities must either use the excess phosphate in the process of water treatment or convert dissolved phosphates into suspended particles, which settle and are removed from the wastewater as part of a sludge management program. In order to achieve effective removal without the creation of excessive sludge, chemical precipitants must be dosed in accurate quantities.

Implementation of efficient precipitant dosing reduces operational costs of chemical purchases, and cuts sludge handling costs by reducing sludge volume. Online measurement with the CA80PH helps to optimize dosing control because it is a precise chemical management system that can be used to control dosing delivery with precision similar to laboratory methods, but in real-time.

As with all Endress+Hauser Liquiline analysers, up to four Memosens sensors can be installed to measure additional parameters of the sample including pH, conductivity, ammonia, total dissolved solids, dissolved oxygen, etc. A local display is part of the system and allows operators to configure current outputs, relays, limit contactors and device diagnostics.

An operator can also invoke mathematical functions to calculate values such as pH from two conductivity values according to VGB Standard 405; the difference between two measured values from different sources to monitor membranes; differential conductivity to monitor the efficiency of ion exchangers; redundancy to monitor two of three voting sensors; and rH calculation from the measured values of a pH and an ORP sensor.

The CA80PH communicates with the plant’s control system via Modbus, standard Ethernet or EtherNet/IP. The analyser also has wireless web server capability, allowing access from any web browser running on an Internet-connected device such as a PC, a tablet or a smartphone.

Advanced diagnostics and data logging capabilities help the treatment plant provide the necessary documentation for regulatory agencies. The analyser has two data logbooks, each with a capacity for up to 150,000 entries.