CAM - Carbon in Ash Monitoring

For plants seeking to improve combustion efficiency and increase high value ash sales, the CAMRAC isokenetic carbon-in-ash monitor is an indispensable tool. The CAMRAC isokinetic flue gas monitoring system delivers highly accurate carbon in ash analysis, based upon truly representative sampling of combustion gas and entrained fly ash. Isokinetic duct sampling allows for online, real time combustion analysis and control that traditional hopper sampling systems can't provide.

Measurement of unburned carbon (LOI) can provide:

• Improved combustion efficiency: The CAMRAC Adaptive Duct Sampling (CAM/ADS) system automatically monitors flue gas fly-ash Loss-On-Ignition (LOI), providing the information that your control system needs for combustion optimization.
• Increased fly-ash sales: CAM/ADS continuously monitors and reports the carbon content of your fly ash. The plant process can be adjusted to obtain a higher percentage of low-carbon, salable fly ash.
• Reduced ash pond loading. Lower density carbon takes up more space.
• Real-time feedback of combustion performance. Allows quick adjustment of boiler and plant operating parameters.
• Improved NOx and opacity control. Better feedback allows more latitude in process control.

How it Works

Multiple sample probes are mounted between the economizer and preheater to collect fly ash at automatically adjusted vacuum rates (minimizing sample bias).

A high-efficiency cyclone separates the fly ash from the sampled combustion gases, which is then routed to a small (5 gm) measurement cell where the sample is weighed.

Next, a minute level of microwave energy is introduced via a proprietary waveguide. The carbon content (LOI) is calculated based on the reflected microwave energy and the mass of the sample.

Finally, the system is purged and ready to take a new sample.

© Schenck Process GmbH, 2012