(116e) Calorimetry and Vapor Suppression Testing of Commercially Available Solidifiers with Hydrocarbon Liquids

Solidifiers are employed to recover oil from oil-impacted environments, reducing long term contamination and environmental impacts.  Solidifiers are dry, granular hydrophobic polymers which immobilize the hydrocarbon liquid within the product and transform the oils into recoverable solids.  They also eliminate the free product and thereby reducing the vapor pressure of the volatile hydrocarbon liquids.  The effectiveness testing is used as a preliminary screening for the selection of solidifiers.  The effectiveness of the solidifiers depends on the type of solidifiers used, the temperature change, solidification time, weight ratio of the solidifier and the hydrocarbon liquid, by-product integrity and vapor suppression effectiveness of the solidifier. The paper presents calorimetry and vapor suppression testing methods to optimize the screening and selection of solidifiers.  The optimum dosage of the solidifiers and hydrocarbon liquids were determined.  A solution calorimeter (Parr Instruments, Model No.6755) was used to measure the heat evolved or absorbed during solidification.  A thermogram obtained from the calorimeter gives the temperature change and heat of solidification values of the commercially available solidifiers with the hydrocarbon liquids like gasoline, diesel and transformer oil.  A test method was developed for testing the volatile organic compound (VOC) concentration of the various solidifiers with the hydrocarbon liquids and the vapor suppression was determined.  From the heat of solidification values, the speed of solidification and the integrity of the byproduct were determined.  Most of the solidifiers behave as VOC suppressants.  The vapor suppression data was used to provide the comparisons between the different solidifiers to aid in solidifier selection in an oil spill scenario and also for giving recommendations for emergency response operations.