Adding graphene to geosynthetics
June 1st, 2022
Q: I have some commercial application questions in the field of geosynthetics. We manufacture graphene powders in the most sustainable way, and it allows us to supply graphene to manufacturers much more economically. As you may have heard, graphene has wonderful material properties atomically to offer, and I am looking for opportunities to leverage its […]
Welding HDPE geomembranes with biogas present
April 1st, 2022
Q: We are a Brazilian company specializing in biogas plants. We have built a big lagoon biodigester with a high-density polyethylene (HDPE) geomembrane cover. Now the cover is leaking liquid contained in the lagoon: We are organizing the repair procedure, and we would like to first investigate state-of-art practices and procedures for welding HDPE geomembranes […]
NSF 61-certified HDPE geomembranes
April 1st, 2022
Q: Hi, we are looking for options for NSF 61-certified high-density polyethylene (HDPE) liners for installation in a potable water tank, 95th-percentile concentration of free chlorine in the tank is 1.2 ppm (1.2 mg/L). The current liner (60-mil [1.5-mm] textured HDPE, installed in 1999) is damaged and needs to be repaired or replaced. We are […]
Methane gas geomembrane permeability
April 1st, 2022
Q: What is the least permeable geomembrane to methane gas? Regarding the permeability of geomembranes to methane gas, could you send me some technical guidelines? A: High-density polyethylene (HDPE) geomembranes are denser (more crystalline) than linear low-density polyethylene (LLDPE) geomembranes and less permeable. The water vapor, solvent and methane transmission (diffusion) of an HDPE barrier […]
Scratch impact on HDPE liners
April 1st, 2022
Q: I have a project where multiple and extensive scratches were created on the high-density polyethylene (HDPE) liner for a reservoir due to poor construction practices. (See the following Figures 2–4.) FIGURE 2 Construction equipment that caused scratches at crest of slope FIGURE 3 Overview of scratches in 60-mil (1.5-mm) high-density polyethylene (HDPE) conductive liner […]
New GSI method for strain hardening of HDPE geomembranes
April 1st, 2022
Traditionally, high-density polyethylene (HDPE) geomembranes are checked for stress crack resistance using the ASTM D5397 single point-notched constant tensile load (SP-NCTL) test (Hsuan, Lord and Koerner [1990]). This test uses notched specimens, surfactant, and elevated temperatures to accelerate the behavior and force a brittle failure in HDPE geomembranes. With today’s high stress crack resistant HDPE […]
Geomembranes for agriculture protect environment
March 9th, 2022
Experts at International Cover Systems Inc. discuss two major applications of geomembranes for agriculture that protect the environment. FIGURE 1 Large geomembrane-lined agricultural lagoon before filling. Photograph courtesy of International Cover Systems Inc. Many of us love meat and dairy, but most put little thought into the waste produced by the animals that bring us these tiers […]
Alternative stress cracking surfactants identified for HDPE geomembrane testing
February 9th, 2022
The Australian geosynthetics testing company ExcelPlas discusses the search for alternative stress cracking surfactants to the pollutant Igepal CO-630. Photograph courtesy Solmax Geosynthetics testing company ExcelPlas in Highett, Victoria, Australia, has identified two alternative stress cracking surfactants for high-density polyethylene (HDPE) geomembranes. Igepal™ CO-630, the non-ionic surfactant used in high-density polyethylene (HDPE) stress cracking bath, […]
EPDM geomembrane for a water application
February 1st, 2022
Q: We are looking at a life-cycle study for the usefulness of an ethylene propylene diene monomer (EPDM) geomembrane for a water conservation application. Request to kindly share the information for our study. Regards. A: An EPDM geomembrane is going to lie flat on the subgrade soil without wrinkles (no field-induced stress). Therefore, it will […]
Fusion-welded HDPE geomembrane patch
February 1st, 2022
Q: I need to make sure of what the minimum area is for a fusion-welded HDPE geomembrane patch with a 60-mil (1.5-mm) thickness that should be fusion welded instead of extrusion welded. Also, when does one need to replace a panel that is damaged (i.e., the percent of damage allowed to be repaired)? Thank you […]