The VCEM 5100 is a low-cost Flue Gas Flow Monitor for Compliance Stack Flow Monitoring that can be utilized in both non-compliance process and EPA compliance applications.
The VCEM 5100 is a gas Flow Monitoring System that can be used as a stand-alone monitor or easily integrated into a complete CEM system. It includes a dedicated Data Display Unit for local data interrogation.
The VCEM 5100 measures the velocity of stack gases using a highly accurate time of flight measurement that is derived from a cross-correlation analysis of the infra-red emissions of the turbulent gas. Two robust infrared detectors are used for the prime sensing, mounted on the stack or duct typically 1m apart in the direction of flow. High-efficiency air curtains are fitted to considerably extend the time between maintenance periods and window cleaning (typically 1 year). The total release is then calculated as follows: Mass flow = Mass concentration x Gas velocity x Area of Duct.
The method used is similar in principle to the technique of flow measurement by the injection of chemical dye or radioactive tracers, where the velocity is derived from the transport time of the tracer between two measuring points a known distance apart. Instead of an artificial tracer being added, the naturally occurring turbulence of the gas stream is used as the tracer.