The overall $251 million PRTC project will house contingency training of troops, and the joint-use building will help the 554th house and maintain its more than 400 pieces of construction equipment. True to its self-sustaining form, a majority of the construction activity will fall under the responsibility of the 554th RHS. This includes blasting, crushing and screening the aggregate that will serve as the buildings’ foundations and be used in the asphalt mix used to pave the roads.
“The E225P is the only military asphalt plant in Guam,” mentions SSgt. Belmer. In addition to making the mix for the 10 miles of roads, the plant could also be moved for other projects. “We ordered this mobile plant for movement capability in contingency operations,” he adds.
Operating ease, latest technology
Featuring counterflow drum technology and the latest in emissions control, the Terex E225P super-portable plant is capable of producing up to 225 tph of asphalt. The drum is pitched at operating angle on its triple-axle chassis with all ductwork pre-installed, significantly reducing set-up and tear-down times. “The E225P is one of our most portable plant designs, and the base configuration can be moved by truck in only five loads,” says Rodriguez.
A portability enhancing feature, the plant only has 20 plug-and-play cable connections, which is significantly less than traditional portable plants. This design feature not only helps with portability but is especially beneficial for the 820th, stationed in the arid desert conditions of Las Vegas. “All breakers and relay switches are inside the control house, so sand can’t get into them,” explains Hagglund. “Sand would get into our old plant and blow the breakers.”
The rest of the RHS plant components consist of an 85-ton self-erect silo, four cold-feed bins, liquid AC tank, control house and Roto-Aire RA218 baghouse. Specifically designed to match mixer production, the RA218 offers a 40,000-cfm capacity and a 4.5 to 1 air-to-cloth ratio to efficiently remove particulates from exhaust gases. “The new baghouse is much more efficient than our old,” adds Hagglund.
One significant difference between the new E225P and the model it replaced lies in a component that increases mix design flexibility. The new plant can produce mixes as either warm or hot mix asphalt. “Warm mix,” says Hagglund, “is the wave of the future. This system allows us to produce asphalt at lower temperatures, increase haul distances and reduce emissions by up to 14%.”
The Terex warm mix asphalt system uses a foamed technology that expands binder to more readily coat the aggregate at lower temperatures. Its patented, field-proven expansion chamber is mounted inline on the plant’s existing AC supply line and features single-point mixing of water and asphalt binder.
It is a cost effective way for lowering asphalt production temperatures by up to 90° Fahrenheit with production capacities reaching 600 tph.
The system comes complete with a 250-gallon water tank with auto refill. Once water in the tank reaches a prescribed low point, the plant controls automatically turn on water flow to refill the tank, so the plant can continue to make warm mix asphalt without stopping.
A high level marker shuts off the flow of water to avoid overfilling. The system’s water meter includes a “no flow” indicator to alert the plant operator of water flow restrictions when making warm mix.
A final creature comfort that RHS operators like on the new plant is the Impulse II plant control system. The programmable logic controller based controls package features a high-speed computer processor and easy-to-use Windows operating system. “The control system on our old plant was harder to use than Impulse II,” says Hagglund. “The new system is laid out in a step-by-step manner that is much easier to pick up and run.”
The user-friendly Impulse II plant controls system provides instructions and guides the operator through detailed step-by-step procedures for plant component calibration. Plant operators can easily input asphalt mix recipes using screen menus or quickly import mix designs from Excel spreadsheets. The system stores virtually an unlimited number of mixes on the computer’s internal hard drive. Additionally, the Impulse II system offers advanced, detailed diagnostics for plant trouble-shooting.