Cement Hydrocarbon Characterization

A bench-scale rotary reactor, designed by Reaction Engineering International and located at the University of Utah, has been developed to investigate hydrocarbon loadings for samples such as cement kiln raw feed material and contaminated soils. The reactor was used to quantify raw material hydrocarbons for over 75 different cement plants in a study performed by REI for the Portland Cement Association (PCA). In addition, the reactor has been used to assist a variety of different cement plants with site-specific hydrocarbon problems. The reactor has also been used for a variety of bench-scale tests involving contaminated superfund soils and sludges, waste plastic pyrolysis and other applications.

The rotary reactor is approximately 4 inches in diameter by 4 inches long. Rotation rates of up to 3 rpm are achievable. Heat is supplied to the rotary reactor via induction coils. A maximum heating rate for dry material (< 30 percent water by volume) is approximately 50 ºF/minute. Mean bed temperature is continuously measured with a thermocouple located in the solids. Heated or ambient temperature purge gases of desired initial composition (inert, reducing, oxidizing) enter the system through a swivel joint and pass through the support tube. The purge gases mix with evolving gases from the solids and exit the kiln cavity through the exit swivel joint. Gas samples (CO, CO2, O2, SO2, NOx, THC) and particulates can be continuously collected from exhaust. In addition, an on-line microGC system or FTIR spectrophotometer can be connected to the exhaust line for other gas analyses.