A by-product of the burning of pulverized coal in electric power plants is sulfur dioxide (SO2) gas. To comply with the 1990 Clean Air Act, many plants have installed wet scrubber Flue Gas Desulfurization (FGD) systems to reduce their SO2 emissions. Due to its low-cost and availability, limestone is the most extensively used reagent. The limestone slurry reacts with the flue gas in the absorber, removing the SO2. The limestone in the slurry is converted into calcium sulfite, air is then introduced and oxidizes the sulfite into calcium sulfate which is then filtered and dewatered. This waste material is then either disposed of in ponds, landfills or sold as ingredients in the manufacturing of gypsum wallboard, cement or used as a fertilizer additive.
Controlling the density of the slurries before and after the scrubbing process is critical. Limestone slurry is very abrasive and has a caustic pH, making density measurement with in-line gages very difficult and expensive.
Ronan's non-contact gamma density gauges mount externally to the pipe and are therefore immune to the abrasive solids and caustic chemicals present in the slurries. This results in low maintenance and less cost as exotic materials are not required. The accuracy of Ronan gauges is high because density is directly measured as a mass in a given volume, not inferred as with other volumetric technologies. By inferring density, the measurement is prone to errors because of varying process variables. No sampling of the slurry is required, eliminating the need for bypass piping.
Radiometric Measurement provides accurate and reliable solution to measure slurry density, with low cost
of ownership. Ronan expert engineers work directly with process engineers to customize a system to meet your needs.