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Release into the environment

The primary processes determining the fate of crude oils and oil products after a spill are (1) dispersion, (2) dissolution, (3) emulsification, (4) evaporation, (5) leaching, (6) sedimentation, (7) spreading, and (8) wind. These processes are influenced by the spill characteristics, environmental conditions, and physicochemical properties of the material spilled. [Pg.111]

The physical transport of oil droplets into the water column, called dispersion, is often a result of water surface turbulence but may also result from the application of chemical agents (dispersants). These droplets may remain in the water column or coalesce with other droplets and gain enough buoyancy to resurface. Dispersed oil tends to biodegrade and dissolve more rapidly than floating slicks because of high surface area relative to volume. Most of this process occurs from about half an hour to half a day after the spill. [Pg.111]

Generally, dissolved aromatics may be found quite far from the origin of a spill, but entrained hydrocarbons may be found in water close to the petroleum source. Oxygenates such as methyl-f-butyl ether (MTBE) are even more water soluble than aromatics and are highly mobile in the environment. [Pg.112]

Certain oils tend to form water-in-oil emulsions (where water is incorporated into oil) or mousse as weathering occurs. This process is significant because, for example, the apparent volume of the oil may increase dramatically, and the emulsification will slow the other weathering processes, especially evaporation. Under certain conditions, these emulsions may separate and release relatively fresh oil. Most of this process occurs from about half a day to two days after the spill. [Pg.112]

Evaporative processes are very important in the weathering of volatile petroleum products and may be the dominant weathering process for gasoline. Automotive gasoline, aviation gasoline, and some grades of jet fuel (e.g., JP-4) contain 20 to 99% highly volatile constituents (i.e., constituents with fewer than nine carbon atoms). [Pg.112]


Potassium permanganate under RCRA definition meets the criteria of an ignitable waste, and if discarded is considered a ha2ardous waste. The reportable quantity (RQ) (220) for potassium permanganate is 45.4 kg (100 lbs) and releases into the environment greater than this value must be reported to the U.S. Coast Guard National Response Center. [Pg.526]

Batteries. Many batteries intended for household use contain mercury or mercury compounds. In the form of red mercuric oxide [21908-53-2] mercury is the cathode material in the mercury—cadmium, mercury—indium—bismuth, and mercury—zinc batteries. In all other mercury batteries, the mercury is amalgamated with the zinc [7440-66-6] anode to deter corrosion and inhibit hydrogen build-up that can cause cell mpture and fire. Discarded batteries represent a primary source of mercury for release into the environment. This industry has been under intense pressure to reduce the amounts of mercury in batteries. Although battery sales have increased greatly, the battery industry has aimounced that reduction in mercury content of batteries has been made and further reductions are expected (3). In fact, by 1992, the battery industry had lowered the mercury content of batteries to 0.025 wt % (3). Use of mercury in film pack batteries for instant cameras was reportedly discontinued in 1988 (3). [Pg.109]

A knowledge of the molecular composition of a petroleum also allows environmentalists to consider the biological impact of environmental exposure. Increasingly, petroleum is being produced in and transported from remote areas of the world to refineries located closer to markets. Although only a minuscule fraction of that oil is released into the environment, the sheer volume involved has the potential for environmental damage. Molecular composition can not only identify the sources of contamination but also aids in understanding the fate and effects of the potentially hazardous components (7). [Pg.164]

The safety and environmental impact of the production of industrial enzymes can be evaluated on three different levels, ie, the potential risk if the microorganisms, their products, or both are released into the environment the possible health hazards to staff working with the microorganisms, their products, or both and safety when products are used by the consumer. [Pg.303]

Selective removal of nickel from copper alloys is common. However, denickelification does not commonly cause the affected component to fail. Rather, the liberated nickel may deposit downstream and/or be released into the environment. [Pg.296]

Disposal or other release into the environment should be employed only as a last resort and should be conducted in an environmentally safe manner. [Pg.458]

EEC Directive on the deliberate release into the environment of genetically modified organisms... [Pg.561]

The main purpose of pesticide formulation is to manufacture a product that has optimum biological efficiency, is convenient to use, and minimizes environmental impacts. The active ingredients are mixed with solvents, adjuvants (boosters), and fillers as necessary to achieve the desired formulation. The types of formulations include wettable powders, soluble concentrates, emulsion concentrates, oil-in-water emulsions, suspension concentrates, suspoemulsions, water-dispersible granules, dry granules, and controlled release, in which the active ingredient is released into the environment from a polymeric carrier, binder, absorbent, or encapsulant at a slow and effective rate. The formulation steps may generate air emissions, liquid effluents, and solid wastes. [Pg.70]

No additloruil monitoring or measurement of the quantities or concentrations of any toxic chemical released Into the environment, or of the frequency of such releases, Is required forthe purpose of completing this form, beyond that which Is required under other provisions of law or regulation or as part of routine plant operations. [Pg.42]

Mass balance (C) should only be indicated it it is directly used to calculate the mass (weight) of chemical released. Monitoring data should be indicated as the basis of estimate only if the chemical concentration is measured in the wastestream being released into the environment. Monitoring data should flfll be indicated, for example, if the monitoring data relates to a concentration of the toxic chemical in other process streams within the facility. [Pg.45]

The analysis of the consequences of nuclear accidents began with physical concepts of core melt, discussed the mathematical and code models of radionuclide release and transport within the plant to its release into the environment, models for atmospheric transport and the calculation of health effects in humans. After the probabilities and consequences of the accidents have been determined, they must be assembled and the results studied and presented to convey the meanings. [Pg.331]

Source Terms and In-Plant Transport the fraction of the inventory that makes it to the environment must be estimated. Computer models are to track the hazardous materials that are released from their process confinement through transport and deposition inside the plant to their release into the environment as a source term for atmospheric and aquatic di.spersion. [Pg.377]

Due to the many variables involved, no attempt is made at this stage to cover the various methods used to remove these pollutants before the water is released into the environment. Table 4.14 lists the common heavy metals in water. [Pg.151]

Measurement of performance. Quality Management requires that measures of performance be established for every activity. These measures include end-of-pipe measurement, such as amounts of material released into the environment or injury rates, and in-process measures of how efficiently you are managing, such as time to review safety improvement proposals or total resources expended on PSM. Each team should be required to identify potential performance measures for the processes they are developing and the activities these processes manage. Many of the end-of-pipe measures will already exist these should be critically examined to ensure that they truly measure performance and are not unduly influenced by other factors. For example, the number of accidents in a fleet of road vehicles is almost directly dependent on the number of miles driven with no improvement in performance, a reduction in miles driven would reduce the number of accidents. [Pg.100]

Fatal accident rate Lost-time injury rate Capital cost of accidents Number of plant/community evacuations Cost of business interruption Cost of workers compensation claims Number of hazardous material spills (in excess of a threshold) Tonnage of hazardous material spilled Tonnage of air, water, liquid and solid effluent Tonnage of polluting materials released into the environment Employee exposure monitoring Number of work related sickness claims Number of regulatory citations and fines Ecological impact of operations (loss or restoration of biodiversity, species, habitats)... [Pg.124]

Tonnage of air emissions, water emissions and liquid and solid effluent and tonnage of hazardous materials released into the environment. These two measures are related to one another. However, the first measure relates the total effluent, including nonpolluting materials. The second measure looks only at the tonnage of hazardous materials contained in the total effluent. Both measures can be important indicators. For example, for solid waste it is important to know the total volume of material for disposal and different upstream treatment techniques may affect the total volume. However, for ozone depleting chemicals, only the quantity of these gases is important and other components such as water vapor may be irrelevant. [Pg.126]

Daily tonnage of hazardous materials released Into the environment (monthly average)... [Pg.132]

Carbon dioxide is released into the environment by human activities such as fuel burning, cement production, and land use. [Pg.241]

Directive 2001/18/EC of the European Parliament and of the Council of 12 March 2001 on the deliberate release into the environment of genetically modified organisms and repealing Council Directive 90/220/EEC... [Pg.12]

In discussing the enviromnental fate of technical DDT, the main issue is the persistence of p,p -DDT and its stable metabolites, although it should be bom in mind that certain other compounds— notably, o,p -DDT and p,p -DDD—also occur in the technical material and are released into the environment when it is used. The o,p isomer of DDT is neither very persistent nor very acutely toxic it does, however, have estrogenic properties (see Section 5.2.4). A factor favoring more rapid metabolism of the o,p isomer compared to the p,p isomer is the presence, on one of the benzene rings, of an unchlorinated para position, which is available for oxidative attack. p,p -DDD, the other major impurity of technical DDT, is the main component of technical DDD, which has been used as an insecticide in its own right (rhothane). p,p -DDD is also generated in the environment as a metabolite of p,p -DDT. In practice, the most abundant and widespread residues of DDT found in the environment have been p,p -DDE, p,p -DDT, and p,p -DDD. [Pg.105]

When DDT was widely used, it was released into the environment in a number of different ways. The spraying of crops, and the spraying of water surfaces and land to control insect vectors of diseases, were major sources of environmental contamination. Waterways were sometimes contaminated with effluents from factories where DDT was used. Sheep-dips containing DDT were discharged into water courses. Thus, it is not surprising that DDT residues became so widespread in the years after the war. It should also be remembered that, because of their stability, DDT residues can be circulated by air masses and ocean currents to reach remote parts of the globe. Very low levels have been detected even in Antarctic snow ... [Pg.105]

As explained in Section 5.2.3, p,p -DDE is much more persistent in food chains than either p,p -DDT or p,p -DDD, and dnring the 1960s when DDT was still extensively used, it was often the most abundant of the three compounds in birds and mammals found or sampled in the field. Since the widespread banning of DDT, very little of the pesticides has been released into the environment, and p,p -DDE is by far the most abnndant DDT residue found in biota. While discussing the ecological effects of DDT and related compounds, effects on population numbers will be considered before those on popnlation genetics (gene frequencies). [Pg.112]

PCBs have been implicated in the decline of certain populations of fish-eating birds, for example, in the Great Lakes of North America. Although their use is now banned in most countries and very little is released into the environment as a consequence of human activity, considerable quantities remain in sinks (e.g., contaminated sediments and landfill sites), from which they are slowly redistributed to other compartments of the environment. There continues to be evidence that PCB residues are still having environmental effects, for example, on birds and fish. [Pg.150]

PCDDs have been released into the environment in a number of different ways. Sometimes this has been due to the use of a pesticide that is contaminated with them. 2,4,5-T and related phenoxyalkanoic herbicides have been contaminated with them as a consequence of the interaction of chlorophenols used in the manufacturing... [Pg.151]

As noted earlier, diverse forms of organomercury are released into the environment as a consequence of human activity. Methyl mercury presents a particular case. As a product of the chemical industry, it may be released directly into the environment, or it may be synthesized in the environment from inorganic mercury which, in turn, is released into the environment as a consequence of both natural processes (e.g., weathering of minerals) and human activity (mining, factory effluents, etc.). [Pg.166]

Organoarsenic compounds have been of importance in human toxicology but have not as yet received much attention in regard to environmental effects. Like methyl mercury compounds, they are both synthesized in the environment from inorganic forms and released into the environment as a consequence of human activity (Environmental Health Criteria 18). They can cause neurotoxicity. [Pg.178]

Both classes of hydrocarbon occur naturally, notably in oil and coal deposits. Aromatic compounds are also products of incomplete combustion of organic compounds, and are released into the environment both by human activities, and by certain natural events, for example, forest tires and volcanic activity. [Pg.181]


See other pages where Release into the environment is mentioned: [Pg.370]    [Pg.129]    [Pg.107]    [Pg.147]    [Pg.99]    [Pg.274]    [Pg.348]    [Pg.129]    [Pg.459]    [Pg.303]    [Pg.2165]    [Pg.46]    [Pg.562]    [Pg.534]    [Pg.548]    [Pg.123]    [Pg.49]    [Pg.1165]    [Pg.113]    [Pg.134]    [Pg.199]    [Pg.63]    [Pg.140]    [Pg.196]   
See also in sourсe #XX -- [ Pg.373 ]




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