ABSTRACT
The overall objective of this study was to evaluate an advanced oxidation process (AOP) used to treat oil and grease (O&G), total petroleum hydrocarbons (TPH), and chemical oxygen demand (COD) of industrial wastewaters generated during barge cleaning operations. This wastewater generally contains appreciable concentrations of O&G, TPH, COD, biochemical oxygen demand (BOD) and benzene, toluene, ethylbenzene and xylene (BTEX) compounds. A bench scale AOP test unit was designed and built for the treatment of the barge cleaning industrial wastewater. The AOP test unit was a 0.33 gpm mobile, modular unit consisting of two contact chambers, two counter current columns and two catalytic chambers. Six experiments were performed using the AOP unit to determine its effectiveness on the reduction of O&G, TPH, and COD. The wastewater was delivered to the AOP from a storage tank. The unit was run for a total of 120 minutes at various gas delivery rates of ozone for each treatment run. Influent and effluent samples were collected at 30 minutes intervals and analyzed for O&G, TPH, and COD. Significant reductions in O&G and TPH concentrations were observed. Oxygen alone indicated a 50% removal efficiency for O&G and TPH. The ozone treatment efficiency was 86% for O&G and TPH at a dosage rate of 12 SCFH and 82% for a dosage rate of 6 SCFH.
Subject(s)
Environmental Pollution/prevention & control , Hydrocarbons/chemistry , Waste Disposal, Fluid/methods , Industry , Oxidants, Photochemical/chemistry , Oxidation-Reduction , Oxygen/metabolism , Ozone/chemistryABSTRACT
Liquid hazardous waste disposal in landfills is usually allowed only after solidification/stabilization. Although various procedures are commonly practiced, little is known about the mechanism(s) of the processes. A particular problem is the interference of organics. Small amounts of organics can interfere with the reaction between inorganic sludges and cementitous matrices. The present communication reports studies of the interaction between selected organic hazardous wastes and Type I Portland cement. Microscopic studies of the structural differences between cements set with water and those set with water plus organic liquids are discussed. In these studies the scanning electron microscope is used to observe samples fractured at 78K. The results provide technical background data on the ultimate stability of critical waste constituents solidified by various binding agents.
ABSTRACT
The use of statistical 't' tests were used to determine lead, zinc, and cadmium enrichment in various Louisiana sediments. Both absolute metal concentrations and trace metal/conservative metal concentration ratios were used in comparing sampled sites to a 110 m deep background core taken just off the mouth of the Mississippi River. Concentration ratios were used to reduce the effects of certain chemical and physical sediment characteristics on the quantity of metal contained in a given sediment.Results from the comparison of sample sites to the background reveal metal enrichment at several sites. The University Lake sampling sites exhibit both lead and zinc enrichment when using both the concentration alone and ratio methods of comparison. Additionally, cadmium enrichment is indicated in the sediments of University Lake when using only the ratio method of comparison. Several sampled sediments in and around the New Orleans metropolitan area exhibited lead and cadmium enrichment.
