Single- or dual-input instrument simplifies maintenance and improves total cost of ownership for dissolved oxygen measurement in wastewater aeration basins and ponds
IRVINE, Calif. (May 19, 2010) — Emerson Process Management today introduced the Rosemount Analytical RDO® optical dissolved oxygen sensor and analyzer for use in wastewater aeration basins and ponds. The sensor is more resistant to fouling than polarographic sensors, an important advantage in wastewater where coating is a common problem. Less sensitivity to fouling means less need for cleaning and reduced operating costs.
The sensor is available with either integral or quick-disconnect cable. A 1-¼ in FPT fitting at the rear of the sensor allows a threaded pipe to be screwed into the sensor so it can be submerged in the basin. One advantage of the sensor’s design is it does not need a flowing sample, so it works well in a low flow basin or pond.
Maintenance is fast and easy and consists primarily of replacing the sensing cap once a year. The analyzer accepts one or two sensors. It has a two-line display, which can be customized to show mg/L (ppm) oxygen, percent saturation, oxygen partial pressure, or temperature for either sensor. The display can also be configured to show the current barometric pressure. The analyzer has two loop-powered 4-20 mA analog outputs assignable to either sensor and to any measurement (concentration, temperature, or partial pressure). Modbus/ RS485 communication is also available as a standard feature. Calibration is simple and can be done either against a referee instrument or in water-saturated air. Air calibration is completely automatic.
“The addition of the optical dissolved oxygen analyzer and sensor to our product line is significant and enables Emerson to continue to be the single-source provider of the most advanced and easy-to-use analysis technologies for wastewater applications,” said John Wright, vice president, Emerson Process Management, Rosemount Analytical. “Our focus has always been to meet real-world customer demands for accuracy, advanced technology, ease of use, lowered cost of ownership and reduced maintenance requirements. The optical sensor fulfills that commitment.”