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Negative effects

There are negetive effects if the recycling process is not performed in [Pg.117]

The new Waste Framework Directive has set a 50% recycling target for household waste. The directive does not stipulate what waste should apply to the municipal waste stream as a whole or individual material fractions within this stream [20]. [Pg.117]

It allows specific waste streams to depart from the waste hierarchy [Pg.117]

Plastics waste separated from a MSW plant has a high energy content and is therefore considered useful for cogasification with coal, which has been detailed by Romey [21]. [Pg.118]


Finally, sulfur has a negative effect on the performance of the catalyst itself. One sees for example in Figure 5.23 that the initiation temperature increases with the sulfur level in the diesel fuel, even between 0.01% and 0.05%. Yet, in the diesel engine, characterized by relatively low exhaust temperatures, the operation of the catalyst is a determining factor. One can thus predict an ultimate diesel fuel desulfurization to levels lower than 0.05%. [Pg.255]

The splitting of the quantum propagator negatively effects the efficiency of the scheme especially if m/M is small, i.e., if the quantum oscillation are much faster than the classical motion and the number n of substeps is becoming inefficiently large. [Pg.402]

Defaunation is a term used to describe the elimination of protozoa from the mmen. Ruminal protozoa allegedly have both positive and negative effects on animal performance (5,34). Defaunation may increase mminal microbial efficiency because less methane is produced and less proteolysis occurs... [Pg.157]

Possible negative environmental effects of fertilizer use are the subject of iatensive evaluation and much discussion. The foUowiag negative effects of fertilizer usage have been variously suggested (113) a deterioration of food quaUty the destmction of natural soil fertility the promotion of gastroiatestiaal cancer the pollution of ground and surface water and contributions toward the destmction of the ozone layer ia the stratosphere. [Pg.246]

Useful materials incorporating fire-retardant additives are not always straightforward to produce. Loadings of 10% are common, and far higher levels of flame retardants are used in some formulations. These concentrations can have a negative effect on the properties and functions for which the materials were originally intended. Product-specific trade-offs are generally necessary between functionaUty, processibiUty, fire resistance, and cost. [Pg.452]

Laboratory experiments using rodents, or the use of gas analysis, tend to be confused by the dominant variable of fuel—air ratio as well as important effects of burning configuration, heat input, equipment design, and toxicity criteria used, ie, death vs incapacitation, time to death, lethal concentration, etc (154,155). Some comparisons of polyurethane foam combustion toxicity with and without phosphoms flame retardants show no consistent positive or negative effect. Moreover, data from small-scale tests have doubtful relevance to real fine ha2ards. [Pg.481]

Fresh butane mixed with recycled gas encounters freshly oxidized catalyst at the bottom of the transport-bed reactor and is oxidized to maleic anhydride and CO during its passage up the reactor. Catalyst densities (80 160 kg/m ) in the transport-bed reactor are substantially lower than the catalyst density in a typical fluidized-bed reactor (480 640 kg/m ) (109). The gas flow pattern in the riser is nearly plug flow which avoids the negative effect of backmixing on reaction selectivity. Reduced catalyst is separated from the reaction products by cyclones and is further stripped of products and reactants in a separate stripping vessel. The reduced catalyst is reoxidized in a separate fluidized-bed oxidizer where the exothermic heat of reaction is removed by steam cods. The rate of reoxidation of the VPO catalyst is slower than the rate of oxidation of butane, and consequently residence times are longer in the oxidizer than in the transport-bed reactor. [Pg.457]

Water reuse is usually a question of the tradeoff between the costs of raw water and the costs associated with treatment for reuse and for discharge. If biological treatment is to be employed, several factors must be considered. These are an increase in concentration of organics, both degradable and nondegradable. This may have a negative effect in terms of final effluent toxicity. An increase in temperature or total dissolved soHds may adversely affect the performance of the biological process. [Pg.176]

Verapamil (Table 1), the first slow channel calcium blocker synthesized to selectively inhibit the transmembrane influx of calcium ions into cells, lowers blood pressure in hypertensive patients having good organ perfusion particularly with increased renal blood flow. Sustained-release verapamil for once a day dosing is available for the treatment of hypertension. Constipation is a prominent side effect. Headache, dizziness, and edema are frequent and verapamil can sometimes cause AV conduction disturbances and AV block. Verapamil should not be used in combination with -adrenoceptor blockers because of the synergistic negative effects on heart rate and contractile force. [Pg.142]

These universal concentrates are preferred if they can be used, because inventorying costs can be reduced it is not necessary to stock different concentrates for different colorants. In some performance polymers this concept is not appHcable because the universal vehicles have a negative effect on weathering, transparency, or processing performance. [Pg.456]

Another aspect to consider in the design of closed-drying systems is the drydown time. The drydown time is the period requited for the system to dry down from its initial water concentration (or partial pressure) to a concentration that approaches equihbrium with the desiccant. During this time, the system is not fljlly protected from the negative effects of the moisture that the desiccant is designed to remove. In such a system, the instantaneous drying rate is proportional to the water content at any time (18). [Pg.509]

AH detergent proteases are destabilized by linear alkylbenzenesulfonate (LAS), the most common type of anionic surfactant in detergents. The higher the LAS concentration and wash temperature, the greater the inactivation of the enzyme. The presence of nonionic surfactants, however, counteracts the negative effect of LAS. Almost aH detergents contain some nonionic surfactant therefore, the stabHity of proteases in a washing context is not problematic. [Pg.294]

The UV spectra of thiirane 1-oxide and (15,25)-(+)-2-methylthiirane 1-oxide show a broad maximum at about 205 nm (e —23 000). The latter shows a positive Cotton effect at low energy followed by a negative effect at high energy. The lowest excited states of thiirane 1-oxide involve excitations from the two lone pairs of the oxygen atom (79G19). 2,3-Diphenylthiirene 1-oxide and 1,1-dioxide show absorption due to the 1,2-diphenyl-ethylene chromophore. [Pg.138]

One of the primary concerns of all power plants is to ensure high electricity production and reduce hazardous and waste substances. In that way green electricity could be produced. It is essential to monitor the presence and movement of impurities in various measuring sites in air, water and soil [1]. The presence of hazardous species in these eco-systems, even at low-mg/1 levels, has negative effects for nature and human beings [2, 3]. [Pg.229]

A wide variety of animal species are subjected to the administration of drugs during their lifetime.The various animal species can encounter drugs and other dietary additives by different routes and this is dependent on the environment in which they are kept. Intensively reared animals tend to have considerable consistency in the components of their diets and thus are much less likely to encounter the range of naturally produced compounds that extensively produced animals encounter. The desire for less expensive dietary constituents and increased efficiency of use has induced feed manufacturers and producers to add enzyme supplements to diets of most farmed animals to reduce the negative effects of indigestible dietary carbohydrates, refactory proteins and unavailable minerals such as phosphorus. This use of dietary additives to improve nutrient utilization and environmental consequences of feeding animals intensively has been the subject of intense research activity in the last five years. " The... [Pg.90]

Figure 20-9 shows the negative effect of uninsulated heating elements on corrosion protection. In a 250-liter tank, an electric tube heating element with a 0.05-m surface area was screwed into the upper third without electrical separation, and in the lower third a tinned copper tube heat exchanger with a 0.61 -m surface area was built in. The Cu heat exchanger was short-circuited for measurements, as required. For cathodic protection, a potential-controlled protection system with impressed current anodes was installed between the two heating elements. The measurements were carried out with two different samples of water with different conductivities. [Pg.454]

The presence of these low molecular weight tackifiers and plasticizers may also have other negative effects on the PSA performance. For example, the reduced entanglement of the polymer typically reduces the cohesive strength of the PSA, although crosslinking may be used to compensate for this loss in property. Plasticizers and tackifiers may also be susceptible to migration and/or oxidation, both... [Pg.502]

The adhesive properties the other monomers were also evaluated, alone and as mixtures with ethyl cyanoacrylate. The addition of DEMM to ECA has an obvious negative effect on adhesion, as can be seen in Fig. 5. [Pg.853]

In addition to forced draft systems, induced draft systems are also used. The induced draft system is slightly more expensive but is recommended when particulate, or organic oils are present. Particulates impact upon a forced draft fan and will have a negative effect on the system performance. If the process stream is clean a forced draft system is appropriate. [Pg.483]

Green, G. H. (1982). Positive and negative effects of building humidification.. ASHRAE Trans, 88(1), 1049-1061,... [Pg.194]

The flat supply air unit can be built of, for example, sheet metal as a box with one side perforated. The area of the perforated side must be slightly wider than the area to be protected since the acceleration of the plume (if colder supply air than the surrounding air is used) will cause the cross-section to be reduced. A uniform velocity profile is important to achieve the desired result divergences may result in negative effects to such a degree that the aim will not be reached. The use of a fabric felt filter downstream of the perforated plate to produce a more uniform velocity profile is therefore recommended. ... [Pg.924]


See other pages where Negative effects is mentioned: [Pg.206]    [Pg.206]    [Pg.12]    [Pg.517]    [Pg.156]    [Pg.378]    [Pg.321]    [Pg.455]    [Pg.4]    [Pg.228]    [Pg.373]    [Pg.99]    [Pg.188]    [Pg.412]    [Pg.27]    [Pg.249]    [Pg.129]    [Pg.294]    [Pg.228]    [Pg.73]    [Pg.121]    [Pg.141]    [Pg.255]    [Pg.783]    [Pg.895]    [Pg.255]    [Pg.389]    [Pg.38]    [Pg.207]   
See also in sourсe #XX -- [ Pg.11 ]

See also in sourсe #XX -- [ Pg.7 , Pg.31 ]




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