MCERTS Certification Achieved for pH Measurement Instruments

ABB (UK) has achieved MCERTS certification for its AX400 pH measurement system. Tested in a field trial conducted over a period of 9 months on an effluent discharge at Pembroke Power Station, the AX400, coupled with ABB’s 7650, 7651, 7660 pH sensors, successfully demonstrated its suitability for use in treated wastewater, untreated wastewater and receiving water applications.

The achievement of MCERTS certification means that ABB’s AX400 pH measurement systems can be used in applications such as the power industry and potable water treatment.

The measurement of pH and Redox (ORP) in high purity water applications in power plants requires a number of essential elements to achieve accurate and stable readings. These include a stainless steel flowcell to minimise static effects and a reservoir-fed reference junction that overcomes KCI depletion and blockage to ensure a stable junction potential and simple reference junction replacement for low-cost maintenance.

The 7660 system has been proven to meet all these requirements by providing accurate measurement in samples below 20 μS/cm. This is especially ideal in boiler chemistry control applications, which require close control of pH levels. For applications up to 100 μS/cm the 7651 with polypropylene flowcell and the 7653 with a reservoir-fed reference electrode option provide an economical option.

For potable water treatment applications, accurate and stable pH measurement is required for optimum control at the coagulation stage of the process to minimise coagulation costs and treated water quality.

Measuring pH in coagulation processes can be particularly difficult, due to the high level of suspended solids and significant precipitation that can block the reference junction.

To overcome this problem, an ideal pH system should include an optional flowing reference junction
that overcomes KCI depletion and blockage. Other features should also include simple reference
junction replacement to enable low-cost maintenance in samples that contain high levels of
particulates, and the availability of a low resistance glass electrode option to provide fast response in
low temperature applications.

The 7600 Series meets all these requirements. The 7651 with polypropylene flowcell and the 7653 with a reservoir-fed reference electrode are an ideal low-cost option that can be readily replaced and installed. Both systems are highly-suited throughout the potable water treatment process. 

“ABB’s pH measurement systems have long been used throughout a wide range of industries to provide reliable and accurate measurement,” says Mike Sparrey, Analytical Sales Specialist for ABB’s UK Measurement Products business. “We are delighted to have achieved MCERTS certification for our AX400 pH measurement system, which forms part of our commitment to providing users with the best available techniques for their environmental monitoring requirements.”

ABB has extensive experience in the design, development and manufacture of pH measurement equipment for use in even the most challenging environments. Its comprehensive range of pH sensors and transmitters can be used in a wide range of process conditions, including high temperatures and pressures, pure water and contaminated liquids.