December 2008

Focus on moisture and humidity

Moisture generally refers to the presence of water, often in small amounts. Humidity is the amount of water vapor present in the air. Humidity is commonly taken to mean relative humidity. Relative humidity is defined as the ratio of the partial pressure of water vapor in a parcel of air to the saturated vapor pressure of water vapor at a prescribed temperature. Humidity can be expressed as absolute humidity and specific humidity as well.

Self-conditioning flowmeter

Process and plant engineers in rugged industries who must frequently measure various hydrocarbon-based gases with wet particulates will find the Wafer-Cone Flow Meter features a unique self-conditioning design that achieves superior flow measurement accuracy in small line sizes. The flowmeter is ideal for industrial process and plant applications, including coal-bed methane gas extraction. The process of extracting this gas typically includes water within the gas seam in the coal bed, which results in a wet gas with tiny water particulates that are difficult to measure accurately.

The Wafer-Cone relies on differential pressure technology with built-in flow conditioning and achieves flow measurement accuracy of ±1% or better, with a repeatability of ±0.1% in gas, liquid or steam applications, including coal-bed methane recovery. It operates over a turndown range of 10:1.  It is designed for service in small process line sizes from 0.5 to 6 inches, which makes it ideal for a wide range of other industrial applications, such as conventional natural gas wells, chemical refining, as well as industrial waste treatment and even landfill applications where biogas is frequently present and may be utilized for electric power co-generation purposes. 



Loop-powered dew point transmitter

The DewPro MMY 30 is a loop-powered dew point transmitter for analyzing moisture content in dessicant air dryers, pipeline natural gas, and industrial gases. The 4-20 mA output measures dew point temperature or ppm in gases at line pressure or atmospheric pressure.

The DewPro MMY30 features a planar capacitive aluminum oxide sensor for exceptional corrosion resistance, extended calibration stability, quick response times, and an exceptionally low temperature coefficient. An integral flow cell for filtration and flow regulation makes it ideal for monitoring moisture content in a wide range of process environments. An optional integrated display with user interface provides full programming and diagnostic capability.

It offers trouble-free indoor or outdoor mounting, field validation with optional MMY245 moisture analyzer, and microcontroller in electronics Type 4X(IP67) enclosure. Optional integrated display with user interface available, and optional FM approval to Class 1, Division 1, Intrinsically Safe, or explosion-proof.

GE Sensing & Inspection Technologies

Steam sterilizable sensor

Process engineers who need to measure pH in sanitary liquid processes that require steam-in-place (SIP) or clean-in-place (CIP) operation will find the SE Series Steam Sterilizable Electrodes and SF Series Fittings deliver a long-life, lower-cost solution.

The advanced SE Series pH electrodes are 12 mm diameter, gel filled, sealed combination pH electrodes that are designed for use with ECD's SF Series fittings.  These smooth-surface fittings are able to be cleaned/sterilized in accordance with European Hygienic Equipment Design Group criteria. They feature AISI 316L stainless steel wetted materials with a surface finish of Ra = 0.8 µm (optional Ra = 0.4 µm) and use FDA compliant O-ring seals.

The rugged SE Series pH electrodes and SF Series fittings are in-situ steam sterilizable or autoclavable. The rigorous nature of many biotech, food/beverage, and pharmaceutical fermentation processes when combined with SIP or CIP requirements dramatically shortens the life of conventional pH sensors. The SE Series pH electrodes solve this problem with their robust full span pH glass electrode and stable reference electrode.  The longer-life SE Series pH electrodes reduce the need for frequent sensor maintenance, saving technician labor and cutting replacement part expenses to lower overall plant production cost.

Electro-Chemical Devices