Reduction of dust emissions

Driving force for implementation Enviromnental and legal reasons. 

Through improved operation stability (assisted by computer monitoring and control systems) and equipment reliability, the need for plant stops and start-ups is reduced to a minimum. Emergency stops can be avoided by timely identification of deviating conditions followed by the application of a controlled shut down process. 

Through die minimisation of shut downs, including emergency stops, and start ups the emission of VOC as well as dust is reduced. 

The implementation is caused by environmental as well as economic reasons to reduce the loss of product, monomers and solvents. 

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Reduction of dust emissions at furnaces by covering iron runners and using nitrogen blankets during tapping of the blast furnace... 

Apart from these fundamental improvements via procedural change, a number of further measures are specified in Table 9.15, with which a sustainable reduction of the emissions during ore smelting can be achieved (Elgersma etal. 1995). For air pollution abatement from heavy metals, the use of highly effective woven filters as a replacement of electrostatic dust samplers... 

The technique results in a minimisation of dust emissions from moulding and finishing, as compared to sand moulding. The emissions of VOC are eliminated as no gas is emitted for the inert ceramic mould. Additionally the amount of waste (dust, metal) is reduced. The reduction of feeder systems results in a higher 5deld of castings per melt. 

The costs for installing a new dust capture and filtration unit in an existing Polish EAF foundry using two 8.5 t/h melting furnaces are summarised in Table 4.42. Dust emissions have been reduced from 10 - 13 kg/h and 145 - 150 mg/Nm to 0.2 - 0.25 kg/h and 2.8 - 2.9 mg/Nm. There has also been a major reduction of difihise emissions from the melting shop. 

Reduction of diffuse emissions of metallic particles and dust. 

StrauB, D. (1994). "Emissionsminderung durch Anwendung modemer Prozesstechniken in einer GieBerei (Reduction of Dust and Gaseous Emissions in a Foundry by Applying Modem Process Techniques - Final Report 1095)", Umweltbundesamt, 0 441-5/145. 

Figure 19.10. Impact on reduction of fine dust emissions as a result of the introduction of hydrogen in road transport comparison of the high-support and fast-learning scenario with the baseline scenario scenario data are taken from Mattucci (2007).

An indication of the environmental effects of hydrogen deployment for each of six European countries (France, Germany, Italy, the Netherlands, Spain, and the UK) is given in Fig. 19.10, where the fine dust emissions are shown for the hydrogen high-penetration scenario. Similar trends are found for other pollutants. The data are normalised in respect to the baseline scenario and show a trend very similar for the analysed countries with a reduction of more than 70% in 2050. The results are an average per country. At a local level, higher reductions can also be achieved if nontechnical measures, such as limitation of city centre access for non-zero emission vehicles, are taken. 

There are basically two ways of controlling dust-borne odours. An effective way seems to be the filtration of the air to remove the dust (41). VAN GEELEN (14) reports on the reduction of the odour emission from a broiler house with 15.000 animals of 65% by means of filter bags when filtering the exhaust air. However, the investments and running costs amounted to about DM 4.00 per 100 birds per year. 

A reduction of the dust content in the air of animal confinements bare not only the chance to diminish the odour emission from the animal houses but can have a positive influence on the animals health and performance, as well. 

In Eugene, new measurements of traffic volume and vehicle speeds on unpaved roads led to a 2600 ton per year reduction in road dust emissions. 

Larger parts of the heavy metal emission of smelters and power plants are deposited in the vicinity (up to 10 km distance) of the emitters. Pb is deposited after long-range transport of fine dust in forests of higher altitudes of the mountain area up to 0.5 kg ha 2T. In Germany, Pb deposition has been decreasing since 1974, mainly due to reduction of the Pb content in petrol (Ulrich 1991). 

The reduction in the emissions of dusts and sulfur dioxide has led during the past few years to an important lowering of the immission and deposition of these substances. The part of nitrogen in total acidification rose generally from 21 to 36%, in the exposed location of Klingenthal (Saxony), from 48-63%. In Saxony, the acidification... 

The rates of precipitation deposition are mapped today and allow a comparison to be made with the results of the forest decline inquiry. To get below the critical load limit for the acid input under the present conditions of reduced input of alkaline dust, it is necessary to reduce not only the S02-emission but also the emission of NO and NHj. The reduction of the nitrogen compounds is also necessary in view of a reduction of the possible eutrophication of terrestrial ecosystems, the nitrate load of the groundwater and surface waters, as well as a reduction of the ozone load. 

The regeneration of sand requires additional energy and causes additional dust emissions and residual dust for disposal. However, the use of regenerated sand in the moulding process allows a reduction in the amormts of lustrous carbon used. 

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