Plastics manufacturing systems

Kazmer D. Plastics manufacturing systems engineering. Cinncinatti, OH Hanser Publications 2009. p. 182-185, 296. 

Kazmer D. Quality control. In Plastics manufacturing systems engineering. Munich Carl Hanser Verlag 2009. p. 387-418 [Chapter 13]. 

Extmsion is a common way for soHd products such as plastics to emerge from closed manufacturing systems. Normally a polymer is hot when extmded and may contain additives and oligomers that are volatile at elevated tempera-tures. The result is Aiming at the extmder head. These fumes can result in employee annoyance, housekeeping problems, and, at worst, depending on composition, health ha2ards. 

Finally, it is very difficult to keep standard solutions for monitoring or recalibration purposes. Control batches should be purged and kept with a dry, inert gas. As long as results are reproduced, the system is considered to be in calibration. The relatively long extraction times usually prohibit the use of these methods for quality control analysis applications in a plastics manufacturing plant. 

This presentation discusses current EU chemical legislation and examines the shortcomings of some of the regulations in place with respect to dangerous chemicals. The Commission White Paper is discussed, and in particular, the REACH system which involves the registration, evaluation and authorisation of chemicals used in food-contact applications. The impact of the REACH system on food-contact plastic manufacturers is examined, with respect to suppliers of monomers and additives, plastic manufacturers, converters and packagers. 

The capital costs for a VaporSep system installed at a plastics manufacturing plant were 300,000. The waste stream contained 5 Ib/hr of hydrogen, 172 Ib/hr of nitrogen, 328 Ib/hr of ethylene, 7 Ib/hr of ethane, and 288 Ib/hr of butene. The system recovered 290 Ib/hr ethylene and 284 Ib/hr of butene. Based on a value of 300 per ton for each ethylene and butene, the plant saved an estimated 700,000 per year by recycling the hydrocarbons (D205549, p. 6). 

The gaseous waste stream at a plastics manufacturing plant consisted of 1620 Ib/hr of nitrogen, 100 Ib/hr of carbon dioxide and oxygen, 2370 Ib/hr of iso-butane, and 10 Ib/hr of water. A VaporSep system was installed at a cost of 1.3 million to recover 2325 Ib/hr of iso-butane. If the iso-butane is valued at 200 per ton, the plant saved an estimated 2 million per year (D205549, p. 8). 

Many workers have been exposed to vinyl chloride because of its use in polyvinyl chloride plastic manufacture. The central nervous system, respiratory system, liver, and blood and lymph systems are all affected by exposure to vinyl chloride. Among the symptoms of poisoning are fatigue, weakness, and abdominal pain. Cyanosis may also occur. Vinyl chloride was abandoned as an anesthetic when it was found to induce cardiac arrhythmias. 

These companies require tools that are intuitive, systematic, document-able, and globally supported to remain competitive on a global scale. Moldflow s Manufacturing Solutions products directly address these needs. The Plastics Xpert system applies and automates the process of scientific molding to decrease mold setup time, cycle time, and scrap,... 

Plastics manufactured from prefoamed (pre-expanded) granules such as polystyrene are also composite systems according to the proposed classification. 

A system of code numbers has been recommended by the Institute of Plastic Manufacturers to help identify the various common plastics. These are shown in Table 41-13, p. 486. 

Because the acceptance criteria AC 174 do not concern materials from which railing systems are made, whether they be wood, concrete or WPCs, composite materials appeared to be in a difficult situation. Nonstructural (as yet) materials should in fact serve as structural, such as in railing systems. That is why most of manufacturers of composite (or plastic) railing systems use reinforcing components, such as wood posts covered with composite (or plastic) sleeves, and metal (steel or aluminum) inserts in support (top and bottom) rails. 

Anonymous, Information system on plastics waste management in Western Europe — European Overview, Association of Plastics Manufacturers in Europe (APME), 1997a. 

A number of other specialty polymers are used in packaging as well. Recycling of these materials is essentially nonexistent. Small amounts may be incorporated in mixed-plastic recycling systems that manufacture items such as plastic lumber. The relatively small amounts of these plastics that are available for recovery, and the additional complication that they often form part of multilayer structures, make their recovery and recycling as pure materials impractical in most cases. 

Hamos GmbH of Penzberg, Germany, also has an IR-based plastics identification system for recycling applications. The compaw also manufactures equipment for color sorting that can be used in recycling processes. ... 

A variety of gases are used to transfer solids from one location to another nitrogen, air, chlorine, and hydrogen. When properly fluidized, solids respond like fluids. Solid transfer requires small, granular, porous solids that respond positively to aeration. Several examples of industry processes that use this procedure are modern plastics manufacturing (granules, powder, flakes), catalytic cracking units, and vacuum systems. 

Ethylene glycol is commonly used as antifreeze in automobiles. The feedstock includes pure water and refined ethylene oxide. This system combines a blending feed tank, glycol reactor, and a series of distillation columns. Olefin manufacturing includes three major processes the first converts natural gas to ethylene, propylene, or butane the second produces isobutylene and isoamy-lene from hydrocarbon feedstocks the third converts gas oil feedstocks into high-octane gasoline, distillates, and C2-C5 olefins. Plastics manufacturing employs a number of polymer processes that handle polyethylene, polypropylene, and butyl polymers. 

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