Minimizing Pollution

University of Maryland, Waste Minimization/Pollution Prevention Plan, University of Maryland, Baltimore, MD, available at http //www.ehs.umaryland.edu/Waste/wastemin.htm, 2007. 

Within the broad framework of sustainable development, we should strive to maximize resource efficiency through activities such as energy and nonrenewable resource conservation, risk minimization, pollution prevention, minimization of waste at all stages of a product life-cycle, and the development of products that are durable and can be re-used and recycled. Sustainable chemistry strives to accomplish these ends through the design, manufacture and use of efficient and effective, more environmentally benign chemical products and processes". 

WASTE MINIMIZATION, POLLUTION PREVENTION, DESIGN FOR ENVIRONMENT, MATERIAL SUBSTITUTION, DEMATERIALIZATION,... 

The terms of zero emission, zero discharge, cleaner production, waste minimization, pollution prevention, design for environment, material substitution, and dematerialization are all closely related, and each is self-explanatory. The U.S. Environmental Protection Agency (USEPA), the United Nations Industrial Development Organization (UNIDO), and other national and international organizations at different periods of time have promoted each [8,19,23,30-34,39-46]. 

UNIDO. Minimizing Pollution from Fertilizer Plants, Report, Expert Group Meeting, Helsinki, ID/ WG 175/19, 1974. 

The present study is now focusing attention on feedback loop control where forcing will be used to reduce instabilities and minimize pollutants in swirling flames. 

Figure 14.5 Modified-ESI source for the direct infusion of undiluted ILs. A stainless steel wire is placed in the spray, leading to the optimal vaporization of the IL. Additionally, an orthogonal ESI source is used. Only a part of the IL ions is transferred into the MS, thus minimizing pollution of the source. (Modified from Dyson, R J. et al.. Direct probe electrospray (and nanospray) ionization mass spectrometry of neat ionic liquids. Chem. Commun., 2204, 2004. Reproduced by permission of the Royal Society of Chemistry.)...

Sample preparation techniques that prevent or minimize pollution in analytical laboratories, improve target analyte recoveries, and reduce... 

Boerner, D.A. Recycling the Paper Forest, Amer. Forests, 37 (July/August 1990). Bumble, S. Computer Simulated Plant Design for Waste Minimization/Pollution Prevention, Lewis Publishers. Boca Raton, FL, 2000. 

Automatic Cooling Tower Control System Minimizes Pollution Feitler, H. Townsend, C. R. 

Organic agriculture practices cannot ensure that products are completely free of residues however, methods are used to minimize pollution from air, soil, and water. 

Chemical reactors are the most important features of a chemical process. A reactor is a piece of equipment in which the feedstock is converted to the desired product. Various factors are considered in selecting chemical reactors for specific tasks. In addition to economic costs, the chemical engineer is required to choose the right reactor that will give the highest yields and purity, minimize pollution, and maximize profit. Generally, reactors are chosen that will meet the requirements imposed by the reaction mechanisms, rate expressions, and the required production capacity. Other pertinent parameters that must be determined to choose the correct type of reactor are reaction heat, reaction rate constant, heat transfer coefficient, and reactor size. Reaction conditions must also be determined including temperature of the heat transfer medium, temperature of the inlet reaction mixture, inlet composition, and instantaneous temperature of the reaction mixture. 

Clearly, minimizing pollutant is easy to obtain by simply injecting less fuel in a chamber. The problem however is that below a certain equivalence ratio (i.e. below a certain amount of kg of fuel per kg of air), combustion simply stops [379 306 340]. The existence of this flammability limit makes optimization delicate because bringing the combustor close to extinction is dangerous (for aircrafts and helicopters for example, that is definitely something which must be avoided for obvious reasons). 

We have discussed various molecular devices created from supermolecules in this chapter. Molecular level techniques and science will play an important roles in the development of nanotechnology in the twenty-first century. Ultrasmall devices with huge information densities will minimize pollution and energy waste, and improve our lifestyles. Tiny robots will be used in medical applications. Excursions into space - manned and unmanned - will benefit enormously from the use of nanomachines and the products of nanotechnology, which should lead to much cheaper and safer space missions. 

In an effort to reduce exhaust to the atmosphere, save heat, minimize pollutant discharges, and keep costs at a minimum, partial recycle is used (Cook, 1996). 

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