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Separation and Sorting

Other than for incineration and some of the newer chemical recycling technologies, sorting of plastic waste into polymer types is of fundamental importance. In order to make separation easier for the consumer an international plastic recycle code mark is printed on larger items (Table 2.3). Even small amounts of a mixed plastic (sometimes as low as 1%) can have significant detrimental effects on the properties of a recycled polymer and result in it needing to be used in low-value applications. [Pg.50]

A HOPE High-density polyethene Milk detergent bottles, plastic bags. [Pg.51]

A PVC Polyvinyl chloride Food wrap, vegetable oil bottles [Pg.51]

A LDPE Low-density polyethene Shrink wrap, plastic bags [Pg.51]

There are also several commercial separation processes based on spectroscopic techniques, two of which are briefly discussed here. Near-inlfared (NIR) spectroscopy (Chapter 8) is finding increasing use in many forms of pollution control. With respect to polymer separation the common types of polymer have different absorption in the range 14300-400 cm. This, coupled with the very short response times of the [Pg.51]


During geological time, a number of separating and sorting processes—melting, crystallization, solution, precipitation—have concentrated various elements in local deposits. In these, the elements tend to be grouped together in rather stable compounds. These are called minerals. Many of the minerals have compositions similar... [Pg.441]

At the instant of immersion of the electrode in the electrolyte (i.e., at time t = 0), the graph for some species i, say, the positive ions M+, would show that the concentration was independent of x and equal to the bulk concentration c9 (Fig. 6.47). This is because at / = 0, the double layer has not yet been formed, i.e., the interface has not yet become electrified. For t > 0, the anisotropic forces at the boundary begin to operate, and the separation and sorting out of the various charges in the interphase take place. [Pg.126]

Other life-cycle assessments have been conducted on postconsumer-use recycling. One of these studies by Rios et al.,131 focused on the end-of-life recycling of plastics used in electronics. The focus of this paper was on the separation and sorting of various types of plastics for recycling. Another study53... [Pg.262]

Mass spectrometers consist of three components an ionization source, a mass analyzer, and a detector. First, the ionization source adds charge to the proteins or peptides in the sample, typically in the form of a proton to produce positively charged particles, and injects them into a vacuum chamber. Second, a mass analyzer uses an electromagnetic held to separate and sort the ionized peptides. Third, a detector registers the number of ions at each mass-to-charge value. The two most technically demanding components are the ionization sources, which we have discussed in the previous section, and the mass analyzers. [Pg.50]

For primary sources of lead, namely mineral ores, the process of mining and concentrating, indeed, begins at a mine. For secondary sources, this stage of the process is replaced by separation and sorting steps to remove the components in the batteries and CRTs that do not contain lead. The remaining process steps are fundamentally the same. [Pg.159]

Progress in plastic separation and sorting is a key factor in the future development of both mechanical and feedstock recycling. As methods of plastic sorting are improved, the purity and homogeneity of the plastic wastes is increased, which favours the application of more advanced degradation... [Pg.182]

FIGURE 6.21 Typical separation and sorting setups using three main detector systems (a) single detector/single sample (b) multiple detector/single sample and (c) multiple detector/multiple sample. (After Tomaszek, T. 1993. Automated Separation and Sort, Modern Plastics, 34-36 (November).)... [Pg.744]

Tomaszek, T. 1993. Automated separation and sort. Mod. Plast, 34—36 (November 1993). Gorttesman, R. T. 1992. Proceedings of Recycle 92, Davos, Switzerland (April 7-10, 1992). [Pg.749]

Importantly, fibres are commonly blended together in order to give fabric more desirable qualities appropriate for apparel applications. For example, cotton and polyester blends have the breathability and wearability of cotton but will crease less and so require less pressing. A smaU percentage of petrochemical-based fibre elastane is often blended with other fibres for added stretch in both wovens and knits. This wide variety of fibres and fibre blends used in textiles for apparel makes effective recycling difficult due to the complexity of separating and sorting constituent fibres from textile blends. [Pg.105]

Curbside recycling programs usually collect comingled materials, as seen here at a Milwaukee site. Plastics, which make up about 85% ofthis pile, must be separated and sorted for recycling. Thomas A. Holme... [Pg.388]

Separating and sorting the various materials, such as metal coatings, paints,... [Pg.134]

The ions then are separated and sorted according to their mass-to-charge ratio by a combination of electric and magnetic fields. The fields cause the ions trajectories to change based on the ions masses and charges. Then, the sorted ions are detected, and a mass spectrum is obtained. The mass spectrum is a graph of relative intensity (related to the number of ions detected) versus mass-to-charge ratio. Mass spectrometry uses a very small sample size (1g) to obtain results. [Pg.224]

Besides fabricating a cell sheet, TRCSs have recently been applied to a cell separation and sorting system, which is an important technology for the regenerative medicine field. In this section, those applications, which are becoming an important technology in the regenerative medicine field in the future, will be discussed. [Pg.223]

Cell separation or cell sorting from a mixture of cells is also one of important issues in tissue engineering. Monoclonal antibodies have been conventionally used for efficient cell separation and sorting. However, the methods are unable to be apphcable for cells of which their surface-specific markers are unidentified. [Pg.224]

Mechanical recycling makes economic sense where sufficient quantities of homogeneous, separated and sorted waste can be made available. In these cases, the quality of recovered material allows production of similar products in most cases, but in the case of recycled vinyl wallpaper a new composite is developed. [Pg.279]


See other pages where Separation and Sorting is mentioned: [Pg.68]    [Pg.201]    [Pg.201]    [Pg.207]    [Pg.239]    [Pg.190]    [Pg.1344]    [Pg.122]    [Pg.404]    [Pg.506]    [Pg.506]    [Pg.48]    [Pg.1339]    [Pg.224]    [Pg.50]    [Pg.267]    [Pg.362]   


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