Demand loads

Combination of Units of Yieid Efficient Power Load Distribution for Different Demand Loads... 

From 1972 to 1973, Abbott Labs in North Chicago, IL, recovered beers with a BOD5 (five-day biological oxygen demand) load potential of 20,000 Ib/day or greater. In the process, the spent beers were concentrated by multiple effect evaporators to 30% solids and the resulting syrup sold as a poultry feed additive. Any excess was incinerated in the main plant boilers. Abbott Labs reported that an average overall BOD reduction efficiency of the system up to 96% or more could be achieved. 

Note Isc = maximum short-circuit current at PCC IL = maximum fundamental frequency demand load current at PCC (average current of the maximum demand for the preceding 12 months) h = individual harmonic order THD = total harmonic distortion, based on the maximum demand load current. The table applies to odd harmonics even harmonics are limited to 25% of the odd harmonic limits shown above. 

Case name Technology Maximum power demand Load type... 

Furnaces usually have to deal with on-demand load changes, i.e., a customer instantaneously needs more steam or more heat input to a unit. The control system on the furnace must be set up to respond quickly to these load changes. The process shown in Fig. 7.1 show s a furnace in which a stream is being heated in a furnace. The outlet temperature of the process stream is controlled by adjusting the fuel flowrate. The air flow is ratioed to the fuel flow. This ratio is adjusted by the output signal from an excess oxygen controller that looks at the composition of the stack gas. The use of too much air increases energy consumption, but too little air can lead to air pollution problems due to incomplete combustion. 

It is seen that the basic functions of automatic control are (1) measurement, (2) comparison, (3) computation, and (4) correction. Thus, a mechanism used for measuring the value of a controlled process variable and operating to limit the deviation of this variable from a desired value or set point is an automatic controller. Disturbances which cause deviations in the controlled variables are classified as either supply-load changes or demand-load changes. The automatic controller regulates by making corrections to one or more manipulaUd variables of the system. These points can best be illustrated by a typical process that uses automatic control. 

DEMAND LOAD - The actual amount of load on a circuit at any time. The sum of all the loads which are ON. Equal to the connected load minus the loads that are OFF. 

Load Factor - The ratio of average energy demand (load) to maximum demand (peak load) during a specific period. 

Peak Demand/Load - The maximum energy demand or load in a specified time period. 

Extended MEA lifetime—lasts 20 times longer in demanding load and humidity cycling applications... 

Power shortage for the various reliability states is obtained by calculating the positive difference between demanded load and maximiun load. 

Base-load q)eration is e iecially reasonable for a dedicated heating plant because tiie heating demand load changes rather slowly and the capital cost of a backiq) or power peaking heat source is not large. 

S. Rastogi, A. Kumar, N.K. Mehra, S.D. Makhijani, A. Manoharan, V. Gangal, and R. Kumar. Development and characterization of a novel immobilized microbial membrane for rapid determination of biochemical oxygen demand load in industrial waste-waters. Biosens. Bioelectron., 18 23-29, 2003. 

Furthermore peroxide bleaching strongly increases the amount and influences the composition of dissolved colloidal substances (DCS). A high amount of DCS results in a high COD (chemical oxygen demand) load in the process water and in a loss of quality of the mechanical pulp, e.g. strength properties. 

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