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In addition to complying with established Federal, State and local regulatory requirements for mining activities, worker health and safety issues, air and water pollution regulations, Journagan Construction Company believes that the construction industry should also contribute to recycling efforts in order to minimize the consumption of natural resources.
Numerous waste materials are generated from manufacturing processes, service industries, construction activities and households which have traditionally been disposed of in landfills or construction/demolition disposal facilities. With landfills reaching capacity in many urban areas and tipping fees becoming very expensive for all industries, recycling of traditional and non-traditional waste materials by the construction industry is becoming a necessity as well as a responsibility. The Hot Mix Asphalt Industry has long been a supporter of recycling road and building materials. Journagan Construction Company has historically participated in recycling of waste materials and continues to be a leader in the efforts to develop new technologies to incorporate more non-traditional waste streams into reusable resources. With an “in-house” asphalt mix design laboratory, highly trained and knowledgeable staff and state of the art testing equipment, incorporation of these non-traditional waste streams into a renewable product becomes possible.
A significant volume of recycled material can be generated on each pavement rehabilitation project. Millings removed from existing asphalt pavements can contribute to significant reductions in the volume of raw materials required to produce new asphalt pavements. The millings are generated by grinding and removing the surface portion of an existing asphalt pavement to accommodate placement of a new surface course. This is often required due to the deterioration of the existing pavement and constraints of the existing roadway elevations. Millings generated are composed primarily of previously produced crushed aggregate coated with asphalt cement binder. The reincorporation of this waste product into a new asphalt pavement minimizes the production of new crushed aggregate as well as consumption of virgin asphalt cement. The overall benefits of recycling existing asphalt pavements can be substantial to the environment by greatly reducing the raw material required to produce new asphalt pavements as well as significantly reducing the overall carbon footprint of all manufacturing and transportation industries involved.
Approximately 10 million tons of asphalt roofing shingle scrap is generated each year in the United States. With the large number of waste products generated annually, waste shingles may not seem like a significant problem. However, it has been estimated that waste asphalt shingles represent approximately 1/3 of all construction-related waste reaching land fills. Only wood-related waste and scrap wallboard exceed the volume generated by waste shingles. Waste shingles are an ideal product to be recycled into a Hot Mix Asphalt design. A typical roofing shingle is composed of several layers or base sheets impregnated with asphalt cement and coated with a fine mineral surfacing. Waste asphalt shingles can contain as much as 30 to 40% asphalt cement. Journagan Construction Company has developed programs to recycle both tear-off asphalt shingles generated from re-roofing and the reuse of shingle manufacturing wastes. The raw shingle waste from either source is reduced in size to a fine-grained product by specialized grinding equipment. The ground shingles are then analyzed and tested for incorporation into various mix designs. Ground shingles are added to the virgin asphalt cement in precise volumes and allowed to physically react with the virgin asphalt cement. The extracted asphalt, binding material and fine granules incorporated into the virgin asphalt cement help reduce the dependency on virgin crude, benefit the environment and minimize the cost of production for the consumer.
Approximately 300 million tires are discarded annually in the United States. Of these, approximately 20% are retreaded or resold, 15% are reused as combustion fuel or additives into Hot Mix Asphalt. The remaining 65% (195 million) are stockpiled, land filled or dumped illegally. The use of crumb rubber from discarded tires to modify asphalt cement has been developed over the past 30 to 40 years by the asphalt industry. Scrap tires are first ground into small granules, bagged and transported to the asphalt plant location. Journagan Construction Company utilizes a “wet process” to incorporate the crumb rubber with the asphalt cement. During the “wet process”, crumb rubber is blended with virgin asphalt cement prior to the introduction of aggregate. The crumb rubber and virgin asphalt cement are heated and mixed for several hours prior to their incorporation into the mix in order to promote a chemical and physical bonding of the two products.
Fly ash is the fine particulate matter which is precipitated from the stacks of pulverized coal-fired boilers at electrical power generating plants. Fly ash represents nearly 75% of all ash waste generated in the United States. Fly ash has primarily been used as a mineral filler in Hot Mix Asphalt designs. The extremely fine particles act as an extender of asphalt cement in Hot Mix Asphalt mixtures.
Waste oils generated during routine maintenance of equipment is recycled and reused for fuel to heat the raw materials within most Journagan asphalt plants. The waste oils are refined to remove excess quantities of harmful ingredients which could contribute to excess emissions. A lesser amount is reused as fuel during winter months to help heat maintenance facilities. This reuse of waste oil reduces the volume of refined fuels required to operate and minimizes the carbon footprint of the entire production process.
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