Technologies available

Tertiary recycling. This is used to describe the routes by which materials are used for purposes other than those for which they were originally intended and where the properties of the material are relatively unimportant. For example, waste poly(ethene) from agricultural use may be 

Secondary recycling. This involves the thermal reprocessing of materials and involves the melting and extrusion of post-consumer plastics to generate other articles. An example of this is in the conversion of used PVC soft drink containers into pipes for land drainage. 

Primary recycling. This is the depolymerisation of waste plastics into their constituent monomers or monomer precursors so that new synthetic polymers materials can be manufactured to the same exacting standards as the original materials. An example of this would be in the methanolysis of used poly(ethylene terephthalate) (PET) soft drinks containers to produce dimethyl terephthalate which is a precursor in one of the routes in the manufacture of PET [9]. 

Reuse of articles. This is not a new idea. For many years in the UK, doorstep deliveries of milk have been made in glass containers that are collected after use, sterilised and refilled, extending the useful life con- 

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The energy required to melt and cast recycled magnesium is approximately 6.7 MJ/kg (2865 Btu/lb) (74) compared to the 267 MJ/kg (115,000 Btu/lb) to produce primary magnesium by the most efficient technology available. 

Methyl tert-Butyl Ether (MTBE). Methyl tert-hutyi ether [1634-04-4] is made by the etherification of isobutylane with methanol, and there are six commercially proven technologies available. These technologies have been developed by Arco, IFF, CDTECH, Phillips, Snamprogetti, and Hbls (hcensed jointly with UOP). The catalyst in all cases is an acidic ion-exchange resin. The United States has been showing considerable interest in this product. Western Europe has been manufacturing it since 1973 (ANIC in Italy and Huls in Germany). Production of MTBE in Western Europe exceeded 600,000 tons in 1990. 

There are three main technologies available for carrying out this process diaphragm cells, mercury cells, and membrane cells. Membrane cells are the most recent development, and are generally chosen for new production capacity. 

Use of the.se breakers is gradually waning in the light of more advanced technologies available in an ACB and MCCB. 

There are many types of external water treatment equipment technologies available, and a boiler plant may employ several different processes, either on a stand-alone basis or in combination. For any particular boiler plant system, however, a point is clearly reached at which further external treatment ceases to be cost-effective. At this point, the necessary supplementary or polishing treatment is provided by the use of internal specialty chemicals. 

Despite the significant encroachment of RO and EDI technologies into the premium end of the higher purity water market, there is no doubt that IX remains the most versatile purification technology available. It has by far the longest track record, being perhaps a century old. It is also a robust technology, often the best choice for use in remote boiler plant locations or where maintenance facilities and support services are limited. 

The key characteristic of a RM is that the properties of interest are measured and certified on the basis of accuracy. The means of attaining the true value are varied, and several different philosophies have been utilized in the quest for the best estimate of the true value. The goal of all approaches is arrival at the best possible estimate of the true value a reliable and unassailable numerical value of the concentration of the chemical constituent, under constraints of economics, state-of-the-art analytical technologies, availability of (new and old) methods, analyst competence, availability of analysts and RM end-use requirement. The basic requirement for producing reliable data is appropriate methodology, adequately calibrated and properly used. 

Overview of analytical technologies available to regulatory laboratories for the determination of pesticide residues... 

International year of light and light-based technologies, available http //www.light2015.org/Home.html [May 1, 2015]. 

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