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Uncontrolled industrialization

Point and diffuse sources contribute to heavy metals in sediments. Point sources have dominated the input of heavy metals in surface vaters for most of the past century, and both dated sediment cores and archived sediment samples sho v the impact of uncontrolled industrialization between 1900 and 1970 on sediment composition. Although these point sources are no longer in existence, or they have reduced their output due to regulations, these contaminated sediments are still present in the environment and pose an important management issue of clean-up. Important in this respect are river flood plains and dredging and disposal of old sediments in locks, weirs, and river stretches. In this chapter, the available technologies for clean-up or... [Pg.150]

As the name implies, these operations, if uncontrolled, can cause a serious air pollution problem. The main problem is the odors associated with the process. Examples of such industries are tanning works, rendering plants, and many of the food processing plants such as fish meal plants. In most cases, the emissions of particulates and gases from such plants are not of concern, only the odors. Requiring these industries to locate away from the business or residential areas is no longer acceptable as a means of control. [Pg.90]

For the chlor-alkali industry, an emergency preparedness and response plan is mandatory for potential uncontrolled chlorine and other releases. Carbon tetrachloride is sometimes used to scrub nitrogen trichloride (formed in the process) and to maintain its levels below 4% to avoid fire and explosion. Substitutes for carbon tetrachloride may have to be used, as the use of carbon tetrachloride may be banned in the near future due to its carcinogenicity. [Pg.61]

A commercial advantage was present in many industrial processes. Uncontrolled heat and humidity impacted some products such as chocolate, pasta, textiles, and tobacco. Air conditioning allowed for unifonn and continuous production despite weather conditions, reduced spoilage and waste, and thus saved money—enough in many cases to easily justify the installed and operating costs. [Pg.26]

There is a middle steady state, but it is metastable. The reaction will tend toward either the upper or lower steady states, and a control system is needed to maintain operation around the metastable point. For the styrene polymerization, a common industrial practice is to operate at the metastable point, with temperature control through autorefrigeration (cooling by boiling). A combination of feed preheating and jacket heating ensures that the uncontrolled reaction would tend toward the upper, runaway condition. However,... [Pg.168]

FDA resources are expended in areas based not on their absolute importance but on the lack of industry capability to control a particular concern. When manufacturing processes were primitive, unclean, and uncontrolled, the FDA issued the Good Manufacturing Practices and eventually the Good Laboratory Practices, Good Clinical Practices, and Good Tissue Practices. Together these Practices provide standards for the industry operations. [Pg.634]

A reaction at steady state is not in equilibrium. Nor is it a closed system, as it is continuously fed by fresh reactants, which keep the entropy lower than it would be at equilibrium. In this case the deviation from equilibrium is described by the rate of entropy increase, dS/dt, also referred to as entropy production. It can be shown that a reaction at steady state possesses a minimum rate of entropy production, and, when perturbed, it will return to this state, which is dictated by the rate at which reactants are fed to the system [R.A. van Santen and J.W. Niemantsverdriet, Chemical Kinetics and Catalysis (1995), Plenum, New York]. Hence, steady states settle for the smallest deviation from equilibrium possible under the given conditions. Steady state reactions in industry satisfy these conditions and are operated in a regime where linear non-equilibrium thermodynamics holds. Nonlinear non-equilibrium thermodynamics, however, represents a regime where explosions and uncontrolled oscillations may arise. Obviously, industry wants to avoid such situations ... [Pg.69]

Direct fluorinations with elemental fluorine still are not feasible on an industrial scale today they are even problematic when carried out on a laboratory-scale [49-53]. This is caused by the difficulty of sustaining the electrophilic substitution path as the latter demands process conditions, in particular isothermal operation, which can hardly be realized using conventional equipment. As a consequence, uncontrolled additions and polymerizations usually dominate over substitution, in many cases causing large heat release which may even lead to explosions. [Pg.597]

Site contamination generally results from leakage, spillage, or disposal of industrial wastes, and can arise from the past uncontrolled disposal of chemical wastes or any recent negligence. Contaminated sites are a threat to human beings by the following means of contamination ... [Pg.590]

Uncontrolled dumping of industrial wastes, hazardous wastes... [Pg.45]

For a number of applications within the rubber industry it is necessary to add a desiccant to the compound to remove traces of water present in fillers or derived from chemical reactions taking place during vulcanisation. Failure to remove this water results in uncontrolled porosity in the product, especially in atmospheric cure conditions. [Pg.140]

Antioxidizability and its control are relevant for various areas in medicine and industry. Atherosclerosis, cardiac infarction, malignant growth, and aging are consequences of uncontrolled oxidation. Currently, oxidizability and antioxidants are also actual problems for alternative and complementary therapies like phyto-, helio-, and aero-ion therapy. [Pg.498]

It is well known that uncontrolled chemical waste, including waste storage and treatment facilities, former industrial and agricultural enterprises and military facilities can contribute to health and environmental problems. [Pg.215]

In the process industries, chemicals are converted into other chemicals in a well-defined and well-controlled manner. Uncontrolled chemical reactions occur under abnormal conditions, for example, malfunctioning of the cooling system and incorrect charging. Temperature, pressure, radiation, catalysts, and contaminants such as water, oxygen from air, and equipment lubricants can influence the conditions under which the reactions (controlled and uncontrolled) take place. [Pg.3]

Are accidents always unforeseeable , Proceedings of the annual Loss Prevention Symposium AIChE, New Orleans, pp. 483-492. The remainder of this Chapter is based on a paper by Sonnemans P.J.M., Korvers P.M.W., Brombacher A.C., Beek van P.C., Reinders J.E.A., 2003. Accidents, often the result of an uncontrolled business process — a study in the (Dutch) chemical industry, Quality Reliability Engineering International 19(3), pp. 183-196. [Pg.107]

Fired heaters are extensively used in the oil and gas industry to process the raw materials into usable products in a variety of processes. Fuel gas is normally used to fire the units which heat process fluids. Control of the burner system is critical in order to avoid firebox explosions and uncontrolled heater fires due to malfunctions and deterioration of the heat transfer tubes. Microprocessor computers are used to manage and control the burner system. [Pg.114]

In spite of its current popularity in the pharmaceutical industry, the use of two control groups is opposed by some statisticians on the grounds that a significant difference between the two groups may indicate that the study was compromised by excessive, uncontrolled variation. Haseman et al. (1986), however, analyzed tumor incidence data from 18 color additives tested in rats and mice and found that the frequency of significant pairwise differences between the two concurrent control groups did not exceed that which would be expected by chance alone. [Pg.304]

The information in this publication is applicable to many industrial facilities not covered by process safety regulations such as the OSHA PSM Standard and the Seveso II Directive. Many reactive chemicals are not listed as regulated materials, and chemical reactivity hazards include uncontrolled chemical reactions between materials not considered as highly hazardous, or under conditions not typically encountered in storage and shipping. [Pg.17]


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See also in sourсe #XX -- [ Pg.149 ]




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Uncontrollable

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