Resource utilization of composite insulator silicone rubber

Abstract

Composite insulators provide highly effective insulation support, and their application in power transmission lines has seen rapid growth in recent years. However, every year, a large quantity of composite insulators are scrapped on reaching the end of their service life. Due to the exceptional chemical inertness of the silicone rubber in the insulators, they have poor self-degradation characteristics, and end up filling landfills and occupying a lot of space, which inadvertently endangers the ecological environment. So far, there has not been any effective means to recycle composite insulators. This paper analyzes the material composition and characteristics of the silicone rubber in the core and housing of composite insulators, and proposes a resource utilization approach for the application of the pulverized silicone rubber powder from the insulators in the following three applications: use in producing silicone rubber asphalt at a blending ratio of 15%–18%—the corresponding market demand is large enough to meet the disposal needs of scrapped composite insulators; use in modification of waste rubber powder and blending with ethylene propylene diene monomer rubber (EPDM) at a blending ratio of 10%—as the annual production capacity of EPDM is more than 850,000 tons in China, thousands of tons of waste insulators can be thus disposed; and use as an aggregate for non-slip coatings, which accounts for more than 40% of the coatings material. Thus, there is tremendous scope for recycling waste insulator.