A process for devulcanizing EPDM rubber comprising the step of introducing sulfur-cured EPDM to an extruder, introducing from about 0.5 to about 20 wt % scavenging agent, based upon the total weight of the EPDM and scavenging agent, and mixing and masticating the EPDM at a temperature sufficient to at least partially devulcanize the sulfur-cured EPDM.

A method for forming a geomembrane liner testable for leaks by securing adjacent panels together with the conductivity of the lower surface of an overlying panel broken along a line adjacent the panel overlapping edge, and the overlapping edges sealed along the line. A heat welder has slots for the overlapping panel edges, with a heated wedge between the slots and having a projection to break the conductivity of the overlying panel bottom surface as it passes the wedge. The slots merge to press the liner edges together to heat weld them along the line of broken conductivity as the welder is moved along the panel edges.

Coreless sheet material rolling apparatuses for rolling up sheet material deployed on a deployed surface into a coreless roll for recycling, and methods of rolling up sheet material deployed on a deployed surface into a coreless roll for recycling. The coreless sheet material rolling apparatuses having a main frame portion, a slide frame portion, and a winder assembly.

The invention relates to covers for wastewater treatment lagoons, which are typically covered by expansive stretches of sheet-form, high density polyethylene (HDPE). The invention more particularly relates to improvements in attaching HDPE patches at distributed locations thereon, which patches provide locally increased thickness to the cover in service as seats for attachment of further attachments to the cover, such as for example and without limitation HDPE straps for retention of HDPE grout-filled ballast pipes, and so on.

A process for devulcanizing EPDM rubber comprising the step of introducing sulfur-cured EPDM to an extruder, introducing from about 0.5 to about 20 wt % scavenging agent, based upon the total weight of the EPDM and scavenging agent, and mixing and masticating the EPDM at a temperature sufficient to at least partially devulcanize the sulfur-cured EPDM.

The present invention is related to a method of bonding tarpaulin and tarpaulin manufactured thereby. More specifically, the present invention is characterized in that the engaging area formed by overlapping the first and second tarpaulin fabrics each other is weld-bonded by means of hot air blowing from the first L-shaped nozzle, and the tarpaulin band is weld-bonded along the upper part of said weld-bonded engaging area by means of hot air blowing from the second L-shaped nozzles, wherein said tarpaulin band is melted in its underside by means of hot air from the second L-shaped nozzles and is weld-bonded to the first and second tarpaulin fabrics to entirely cover the engaging area with a sufficient establishment of a widthwise size. Thus, a better strength is provided in the engaging area and the tarpaulin fabric is improved in its robustness, durability and marketability.

A process for devulcanizing EPDM rubber comprising the step of introducing sulfur-cured EPDM to an extruder, introducing from about 0.5 to about 20 wt % scavenging agent, based upon the total weight of the EPDM and scavenging agent, and mixing and masticating the EPDM at a temperature sufficient to at least partially devulcanize the sulfur-cured EPDM.