An ultraMOIST microwave moisture monitor has been installed in a major Australian quarry supplying aggregate to the road building industry. The microwave moisture monitor was installed on the raw material conveyor, which transports a mixture of fine and coarse materials from the crushing and screening plant to the pug mill.
The pug mill mixes the raw material with a predetermined quantity of cement and water to provide contract specification grade of material for delivery to the customer. The plant layout with the raw material conveyor delivering an aggregate and sand mixture to the pugmill. From their the mix is loaded onto a stockpile via a radial stacker.
Once the system had been installed, virtually no commissioning was required and only two point calibration was carried out. The whole process of installation, commissioning and calibration took only two and a half days.
Until ultraMOIST was installed, laboratory moisture results were used to determine whether the product was within specification. The laboratory results usually take up to 30 minutes. This delay means that, either, the truck is kept waiting before delivering the product, or, the truck leaves without a moisture result with the attendant uncertainty whether the load of material will provide optimal handling characteristics.
ultraMOIST uses the industry standard microwave transmission technique for measuring moisture. A low intensity of microwave beam is passed through the conveyor belt and the entire burden. In this way any vertical segregation effects are eliminated. The microwave moisture monitor is non contacting and operates under computer control. Interlocks determine whenever the conveyor is stationary and suspends analysis during such periods.
ultraMOIST is presently in a monitoring role with water addition being made manually based on the ultraMOIST result. A project is presently underway to extend the system to automatic water addition using ultraMOIST water control capabilities.
ultraMOIST microwave moisture monitor from Ultra-Dynamics.