Primary pollution prevention

The increasing use of catalytic processes can substantially reduce waste at the source, resulting in primary pollution prevention. The theoretical process efficiency... 

Green chemistry addresses the environmental impact of both chemical products and the processes by which they are produced. In this book we shall be concerned only with the latter, i.e. the product is a given and the goal is to design a green process for its production. Green chemistry eliminates waste at source, i.e. it is primary pollution prevention rather than waste remediation (end-of-pipe solutions). Prevention is better than cure (the first principle of green chemistry, outlined above). 

While the use of catalysts in secondary pollution prevention, i.e. the clean up of waste, has become well established and is likely to grow well into the 21st century, it is in primary pollution prevention (pollution reduction or avoidance) where there should be a spectacular growth in application and importance. The key areas of clean technology where catalysis can have a major impact are ... 

The urgent need for more environmentally acceptable processes in the chemical industry [74], known as green chemistry [75,76] or sustainable technology, became a general trend in recent years since green chemistry approaches elimination of waste at the source (i.e., it is primary pollution prevention rather than waste remediation, also named end-of-pipe solutions). 

Green chemistry eliminates waste at source that is, it is primary pollution prevention rather than end-of-pipe waste remediation, as is inherent in e first principle of green chemistry prevention is better than cure. Since the mid-1990s, the concept of green chemistry has been widely embraced in both industrial and academic circles [9], One could say that sustainable development is our ultimate common goal and green chemistry is a means to achieving it. 

Implementation of cleaner production processes and pollution prevention measures can yield both economic and environmental benefits. The primary treatment technologies afforded to this manufacturing include the following ... 

This section describes the major industrial processes within the petroleum refining industry, ineluding the materials and equipment used, and the processes employed. The section is necessary for an understanding of the interrelationships between the industrial processes, the types of air emissions, and control and pollution prevention approaehes. Deseriptions of eommonly used production processes, assoeiated raw materials, by-produets produeed are first deseribed. Petroleum refining is the physieal, thermal, and chemical separation of erude oil into its major distillation fraetions, which are then further proeessed through a series of separation and eonversion steps into finished petroleum produets. The primary products of the industry fall into three major categories ... 

Although numerous cases have been documented where petroleum refineries have simultaneously reduced pollution outputs and operating costs through pollution prevention techniques, there are often barriers to their im-plementation. The primary barrier to most pollution prevention projects is cost. Many pollution prevention options simply do not pay for themselves, or the economics often appear marginal. Corporate investments typically must earn an adequate return on invested capital for the shareholders and some pollution prevention options at some facilities may not meet the requirements set by company policies. 

Condensation scrubbing systems are a relatively new technology and are not yet generally commercially available. It may be argued that this is a pollution prevention type of technology since it replaces other approaches to controlling very fine PM, although the primary role is end-of-pipe treatment. 

Charging and tapping emissions are controlled by a variety of evacuation systems and operating practices. Charging hoods, tapside enclosures, and full furnace enclosures are used in the industry to capture these emissions and send them to either the primary hood gas cleaner or a second gas cleaner.1516 Pollution prevention opportunities for the reduction of heavy metals at the BOF are limited as heavy metals are an inherent part of the iron ore material stream, so the higher the iron production, the greater will be the use of the ore. 

Although they are conceptually similar, pollution prevention and accident prevention differ in the response they have thus far received from industry. Although many firms are embracing pollution prevention (some enthusiastically, some more tentatively), far fewer are moving to primary accident prevention. In all likelihood, this disparity is due to a difference in incentives. 

With regard to primary accident prevention, the same economic signals are not really there [2]. Firms do not pay the full social costs of injuries to workers (or to the public) and firms are under-insured. Unlike pollution, which has to be reckoned with as a part of production planning, accidents are rare events and their consequences are... 

Underlying causes fog plus stable high, surface inversion, dispersal of primary pollutant emission Is prevented, accumulate of hydrocarbons sheltered basin, frequent stable highs, accumulation of secondary pollutants from photochemical oxidation... 

The primary environmental legislation in England and Wales that relates to the release and control of waste discharges includes the 1990 Environmental Protection Act, the 1991 Water Resources Act, the 1995 Environment Act and the 1999 Pollution Prevention and Control Act. Some of the more important elements of these acts are discussed below. 

One of the primary methods for pollution prevention is the design and the development of chemical products with lower toxicity and of processes that reduce or eliminate the use of hazardous substances. 

The U.S. Clean Air Amendments of 1977 define two kinds of air quality standards primary standards, levels that will protect health but not necessarily prevent the other adverse effects of air pollution, and secondary standards, levels that will prevent all the other adverse effects of air pollution (Table 22-7). The amendments also define air quality levels that cannot be exceeded in specified geographic areas for "prevention of significant deterioration" (PSD) of the air of those areas. Although they are called "increments" over "baseline air quality" in the law, they are in effect tertiary standards, which are set at lower ambient levels than either the primary or secondary standards (Table 22-8). 

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