Cement and Energy

. . l .. -+' ;-.._ f ~·;):~'~ ;f-:·f~ ,, ., ... . ~.- . . .. ·.·~~ '·:·!. .. -:· ,. Understandably process operators want to cut energy costs by burning fuel more economically, while at the same time maxim ising refractory life, the priority is to obtain optimum combustion conditions from start-up onwards. Combustion specialist Fuel and Combustion Technology International (FCT) have developed warm-up burners which provide solution to these problems. The modelling performed answer this need, thus avoiding all the practical problems and expense associated with first operating and then rectifying plant which is not functioning as expected. To understand and control the complexities offlame behavior, vanous methods are achieve the simultaneous solution of heat, mass and momentum transfer equations under simulated dynamic conditions. employed. Physical modelling extends The interior of one ofthe kilns at Weardale to air, water, chemical mixing and low visualisation .~ techniques. Mathematical model Iing includes [Courtesy: World Cement July 1996] computational fluid dynamics. All these are used to HIGH EFFICIENCY ELECTRIC MOTORS iiN APPLICATIONS ACROSS THE CEMENT ifNDUSTRY Application of Electric Motors in Cement Industry I n a typical cement plant, electric motors can account for up to 85% of the site's electricity costs. Motors are used everywhere, for driving fans, blowers, compressors, conveyors and crushers. This is why the potential energy savings to be gained from installing high efficiency motors are considered more significant for cement plant operators. The operating cost savings from high efficiency motors are often insufficient in themselves to justify replacing existing installed motors. However, when a new motor is to be installed or an existing motor has burnt out and needs replacing, the necessary engineering and maintenance costs drop out of the equation. Under this scenario, it is estimated the additional capital cost ofa new motor can usually be recovered 111 less than two years. However, not all installed motors will benefit from up– grading. For a motor that runs for short periods only, for example, or where the engineering costs are high for rep lacement, rewinding wi II be more cost effective. Whether a failed motor should be repaired or replaced is not a decision to be made when the pressure is on plant engineers to get the motor quickly back into serv– ice . By implementing a company-wide motor manage– ment policy this decision is taken long before the motor fails. The time spent creating a motor management policy will be paid for many times over by reduced energy costs, less downtime and lower stock inventories.