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Control of Acid Mine Drainage Including Coal Pile and Ash Pond Seepage
Published in Donald A. Hammer, Constructed Wetlands for Wastewater Treatment, 2020
A reinforced concrete structure 3.05 m by 18.3 m was initially divided into three 6.1–m sections, with provisions to subdivide the structure into six 3.05–m sections at some later time if desirable (Figure 1). Each compartment was fitted with two drains, one active and one reserve. Drains were 15–cm polyvinyl chloride (PVC) pipe, and active drains consisted of standpipes initially set at 1– m depth. Drains deliver the overflow water to the existing pond. A 0.76–mm Hypalon liner separated one compartment from another to prevent chemical reactions between construction materials, organic substrates, and mine drainage. Baskets with 10– to 15–cm river rock at the upstream end exposed a maximum cross section of organic substrate to mine drainage. Six sampling wells of 15–cm PVC in each compartment allowed water to enter from the lowest 30 cm, the middle 30 cm, and the upper 30 cm of the organic substrates. A small concrete dam inside the tunnel provided head to distribute water to each compartment through insulated PVC lines fitted with ball valves for flow control. Perforated drain pipe (10–cm PVC) across the width of each compartment distributed water to each compartment, and excess water drained into the pond. Compartment sections were filled with 1 m of organic substrates: the first had mushroom compost; the second had equal parts of peat, aged steer manure, and decomposed wood shavings and sawdust; and the third had 10–15 cm of 5– to 8–cm limestone rock below the same mixture as the second compartment. Substrates were initially saturated with municipal water at 3.78 L/min.
Polymer Applications in the Construction Industry
Published in Nicholas P. Cheremisinoff, Elastomer Technology Handbook, 2020
Hypalon is a synthetic rubber that is flame and weather resistant and highly resistant to a large variety of chemicals. It thus has a number of valuable characteristics so vital in a material to be used for flooring.
Wetlands
Published in M. Sengupta, Environmental Impacts of Mining, 2018
A reinforced concrete structure 3.05 × 18.3 m was initially divided into three 6.1-m sections (Figure 8.15). Each compartment was fitted with two drains of 15-cm PVC pipe, one active and one reserve. Active drains consisted of standpipes initially set at a 1-m depth which deliver the overflow water to the existing pond. A 0.76-mm Hypalon liner was used to separate one compartment from another and to prevent chemical reactions between construction materials, organic substrates, and mine drainage. Six sampling wells of 15-cm PVC in each compartment were used to allow water to enter from the lowest 30 cm, the middle 30 cm, and the upper 30 cm of the organic substrates. A small concrete dam inside the tunnel provided head to distribute water to each compartment through insulated PVC lines fitted with ball valves for flow control. A perforated drain pipe, 10-cm PVC, across the width of each compartment distributed water to each compartment, and excess water was drained into the pump.
Studies on properties of coated para-aramid fabric samples developed for military applications – post UVA-340 exposure
Published in The Journal of The Textile Institute, 2023
R. G. Revaiah, T. M. Kotresh, Balasubramanian Kandasubramanian
It can be seen from results that natural rubber-coated sample showed highest decline in the tensile strength post UV exposure followed by Hypalon-coated fabric. In our studies, PU-coated fabric exhibited highest resistance to UV degradation and no noticeable loss of tensile strength was observed. Neoprene-coated fabric exhibited slight decline in the tensile strength compared to PU but offered better resistance to UV compared to Hypalon and NR coatings. These results infer that polyurethane is the best choice of coating where UV intense applications are envisaged. Where applications demand resistance to flame, Neoprene is a better choice compared to Hypalon. NR-coated fabrics are subjected to highest surface deterioration and loss of tensile strength was highest.
Mechanical and Chemical Properties of Harvested Hypalon Cable Jacket Subjected to Accelerated Thermal Aging
Published in Nuclear Technology, 2018
Robert C. Duckworth, Michelle K. Kidder, Tolga Aytug, Leonard S. Fifield, William Glass, Sarah Davis
A cross section of the harvested BIW-manufactured I&C cable is given in Fig. 3. This cable, which was used in an auxiliary space outside the missile barrier of the NPP, is rated for operation at 600 V and contains two 12 American wire gauge (AWG) insulated wires and twenty-two 20 AWG insulated wires. The cable, of 25.4 mm outer diameter, has a jacket of 2.74-mm-thick Hypalon (a chlorosulfonated polyethylene [CSPE]), a thin-foil ground shield, and multiple conductors insulated with ethylene propylene rubber (EPR) of thickness between 1.1 and 1.3 mm. In addition to the EPR insulation, the conductors are covered with a 0.4-mm-thick dyed coating of CSPE to assist circuit connection discrimination and to further protect the EPR.