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Leachate Containment
Published in Syed R. Qasim, Walter Chiang, Sanitary Landfill Leachate, 2017
Polyvinyl Chloride (PVC) liners for swimming pool application were introduced in the early thirties. The geomembrane era began in the 1950s with reservoir liners made from butyl rubber. These thermoset elastomers had been developed during World War II in the search for synthetic rubber. With a growing number of formulations and applications, several names have been given to these liners. Among these names are pond liners, flexible membrane liners (FMLs, the term used by EPA), synthetic membrane liners (SMLs), geomembranes and others (Koerner et al. 1991). Today, the most frequently used liner for waste containment is high density polyethylene (HDPE), primarily because of its high chemical resistance to wastes and leachates.
Protection of Pipelines against Abrasion, Freezing, and Corrosion
Published in Henry Liu, Pipeline Engineering, 2017
Various materials are used for pipe lining and coating. They include tle following: Bitumastic materials — Bitumastic materials such as coal tar, asphalt, or bitumen are used — as both lining and coating — of steel, cast-iron, concrete, and wood pipes.Cement — Cement is often used as a lining for steel and cast-iron pipes. It is a preferred type of lining for transporting saline or brackish water.Lead lining — An old practice no longer in use at present for fear of lead poisoning.Glass — Glass is used as the lining for steel pipe in special applications. Glass lined pipes have the strength of steel pipe and the corrosion resistance of glass pipe. They are especially suited for conveying acids.Rubber — Soft rubber lined steel pipes are sometimes used in slurry transport because they are abrasion resistant. Hard rubber-lined pipes are sometimes used for transporting strong acid and alkali solutions.Brick lining — Bricks were once used to line large diameter conduits but are rarely used today.Fluorocarbon lining — Fluorocarbons, such as Teflon, Kynar, etc., are used when transporting high-temperature and/or corrosive fluids.Thermoplastic lining — PVC, polyethylene, etc. are used when transporting loads at normal temperature. High density polyethylene (HDPE) is used for slurry pipelines to reduce pipe wear.Thermosetting lining — Epoxies, polyesters, etc. can be sprayed on and baked to produce a hard glasslike pipe interior.Galvanized lining and coating — Used on steel pipes. Note that galvanized steel is not suitable for welding.Cladded piping — First, stainless steel or nickel is cladded onto steel plates. Then, the plates are rolled into pipes. Cladding is formed by homogeneous bonding or spot-welding.Wrapping — Tape or encasing is applied around a pipe to increase its resistance to corrosion and abrasion. It can be done on pipes with or without coating. Steel pipes are often coated with tar or bitumen and then wrapped with one or more layers of plastic or kraft paper.
Effect of the geometry on the structural performance of high-density polyethylene small craft joints
Published in Ships and Offshore Structures, 2022
Ayberk Sözen, Gökdeniz Neşer, Murat Bengisu
In today’s marine industry, the use of high-density polyethylene (HDPE) material has gained popularity day by day mainly due to its almost perfect recyclability that relieves the concerns for sustainability of the products. Addition to this advantage over its counterparts, such as fibre-reinforced thermoset plastic (FRP) composites, HDPE has become prominent in the industry with its lightweight, remarkable resistance to marine environmental effects, such as moisture, corrosion, fouling-boring marine organisms, UV, etc. Mechanically HDPE has sufficient tensile and impact strength, toughness, and resistance to abrasion. It is not so suitable to apply HDPE to complex forms; the builders can achieve these complex shapes and compound curvature and part consolidation by applying FRP composites (Marsh 2003; Guillermin 2010; Neşer and Aytekin 2015). Building with HDPE is cost-effective too. It is worth to mention that production with HDPE is much more environment-friendly and safe in terms of produced emissions and occupational health during the building process compared to other thermoset polymer-based fibre-reinforced plastics, such as GRP (Glass-Reinforced Polyester), CRE (Carbon-Reinforced Epoxy), etc.
Potential adverse health effects of ingested micro- and nanoplastics on humans. Lessons learned from in vivo and in vitro mammalian models
Published in Journal of Toxicology and Environmental Health, Part B, 2020
Laura Rubio, Ricard Marcos, Alba Hernández
Different synthetic polymers are used in the constitution of plastics, depending upon their intended use. Among these, low-density polyethylene (LDPE) is employed in packaging materials, and by far is the major component of terrestrial plastic litter in form of plastic bags and sheets (Barnes et al. 2009). High-density polyethylene (HDPE) is utilized among other applications for corrosion-resistant piping, geomembranes, and plastic lumber, while polyethylene terephthalate (PET) is used overall in plastic bottles (Bouwmeester, Hollman, and Peters 2015). Altogether, polyethylene is the most produced polymer comprising more than 40% of the total plastics produced (U.S. Environmental Protection Agency, 2012). Other polymers commonly employed include polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC) and polyactide (PLA) (Andrady and Neal 2009).
Aspects on viscoelasticity modeling of HDPE using fractional derivatives: Interpolation procedures and efficient numerical scheme
Published in Mechanics of Advanced Materials and Structures, 2022
T.C. da Costa-Haveroth, G.A. Haveroth, A. Kühl, J.L. Boldrini, M.L. Bittencourt, F.D. Sasse, M.A. Polak, P.A. Muñoz-Rojas
Polymers with viscoelastic material response have been ever more employed in several branches [1–3]. High-density polyethylene (HDPE) is an example of viscoelastic polymer that has gained wide use in structural applications, mainly in the manufacture of pipes for water and gas distribution. In these situations, the HDPE components are submitted to stress conditions during service, leading to the need of predicting their behavior in long-term use.