Environmental issues organic process wastes

The main objectives of this chapter are to (1) review the different modeling techniques used for sorption/desorption processes of organic pollutants with various solid phases, (2) discuss the kinetics of such processes with some insight into the interpretation of kinetic data, (3) describe the different sorption/ desorption experimental techniques, with estimates of the transport parameters from the data of laboratory tests, (4) discuss a recently reported issue regarding slow sorption/desorption behavior of organic pollutants, and finally (5) present a case study about the environmental impact of solid waste materials/complex... 

Thermoplastics processing operations produce emissions into the air, wastewater, and solid waste resulting from both polymers and additives. Most important are volatile organic compounds emitted from heated cylinders and molds. The identification of such volatiles and the development of analytical techniques for measuring their concentration in the workplace are of paramount importance to establish or revise threshold limit values that would minimize exposure to hazardous chemical substances. Environmental issues in polymer processing are reviewed in References 18 and 19. 

Most significant environmental issues with respect to block copolymer S5m-thesis relate to manufacturing process, taste and odor issues in end use, and solid waste in final disposal of these pol5uners. Manufacturing process issues relate to industrial hygiene, exposure, and volatile organic emissions. In end use, block copolymer/polystyrene blends tend to have taste and odor issues, especially for sensitive food packaging applications. 

In addition to the aforementioned issues regarding the incineration process, other concerns of relevance to public health need to be addressed. For example, hazardous waste to be fed to the incinerator and process effluents resulting from the incinerator should be stored in a manner that does not allow for uncontrolled environmental releases of potentially harmful substances. Dry, dusty materials should be enclosed or otherwise stored to prevent windborne transport of contaminated particulates. Wastes containing volatile organic compounds should be stored under conditions that safely collect and remove gases released from the wastes. 

Consider the issue of designing a recycle reactor to accomplish the degradation of 99.99% of the phenol present at a concentration of 1.1 x 10 M in supercritical water at 380°C and 278 atm. This destruction level is selected on the basis of Environmental Protection Agency standards for thermal treatment of hazardous organic wastes. The corresponding inlet concentration of oxygen is 0.08 M. Prepare a plot of the reactor volume required to process 8 m /h of the supercritical aqueous solution versus the recycle ratio for values of this ratio between 0 and 20. Comment. 

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