Environmental impact of processing

LCAs also focns on the environmental impacts of processes and do not address the social or economic impacts. Althongh there is still debate about the usefulness of snch analyses, LCAs do provide a means of examining the environmental impact of a process in a holistic sense. 

As defined previously, risk is a function of hazard and exposure. In the environmental risk context, hazard is a function of toxicity which is affected by physical/chemical and environmental fate properties and hence chemistry. Green chemistry reduces the risk or environmental impact of processes or products by focusing on the hazard component. 

In order to convert fibers into consumer products, several processes are required in a production seqnence, as indicated in Fignre 7.1. This chapter reviews environmental impacts of each of the above textile processing steps after fiber formation. In addition, information is presented on processing auxiliary chemicals, as well as some general ideas concerning process improvements to reduce wastes and environmental impact of processing. 

Updated and revised ihroughom, this standard reference describes recent advances in the design of tower packings and the commercial application of packed columns such as absorption, stripping, distillation, and extraction. It reflects current changes to improve energy efficiency and reduce the environmental impact of processing operations. 

Stefanis, S. K., Livingston, A. G., Pistikopoulos, E. N. (1995). Minimizing the environmental impact of process plants A process systems methodology. Computers and Chemical Engineering, 19, S39-S44. 

Since process design starts with the reactor, the first decisions are those which lead to the choice of reactor. These decisions are among the most important in the whole design. Good reactor performance is of paramount importance in determining the economic viability of the overall design and fundamentally important to the environmental impact of the process. In addition to the desired products, reactors produce unwanted byproducts. These unwanted byproducts create environmental problems. As we shall discuss later in Chap. 10, the best solution to environmental problems is not elaborate treatment methods but not to produce waste in the first place. 

Microbial processes can also detoxify mercury ions and organic compounds by reducing the mercury to the elemental form, which is volatile (86). This certainly reduces the environmental impact of compounds such as methylmercury, however, such a bioprocess would have to include a mercury capture system before it could be exploited on a large scale with pubHc support. 

Lead Azide. The azides belong to a class of very few useflil explosive compounds that do not contain oxygen. Lead azide is the primary explosive used in military detonators in the United States, and has been intensively studied (see also Lead compounds). However, lead azide is being phased out as an ignition compound in commercial detonators by substances such as diazodinitrophenol (DDNP) or PETN-based mixtures because of health concerns over the lead content in the fumes and the explosion risks and environmental impact of the manufacturing process. 

The Courtaulds Tencel Process. The increasing costs of reducing the environmental impact of the viscose process coupled with the increasing likelihood that the newer cellulose solvents would be capable of yielding a commercially viable fiber process led Courtaulds Research to embark on a systematic search for a new fiber process in the late 1970s. 

Until recently, the NRA has not participated during the approval process in assessing the potential environmental impact of pesticides. However, the NRA does supply monitoring data to MAFF and HSE for pesticide reviews. These occur once a pesticide has been approved for use for a certain length of time, or when further information is needed on an approved pesticide. In supplying these data, the NRA comments on any areas of concern. This contributed to the 1993 ban on the use of atrazine and simazine on non-cropped land. In January 1995 the NRA s National Centre for Toxic and Persistent Substances (TAPS) was made advisor to the DoF, on the potential impact on the aquatic environment of... 

An ElA can be particularly useful in distinguishing the relative environmental impact of alternative sites, processes and strategies for industrial, rural or urban development. Decision-makers to choose the alternative that will provide maximum economic and social benefits with the minimum of environmental disturbance can then use this essential environmental information, together with financial and political considerations. Guidelines for assessing... 

Interpretation. The final stage of the LCA process is connected with identifying which parts of the life cycle have the most significant impacts and at identifying possibilities for improving the total environmental impact of the system under study. 

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