Optimized cogeneration

Power Plants at Chemical Plant Sites by Means of Optimized Cogeneration. 84... 

Multi-stage preheating, pre-calciners, kiln combustion system improvements, enhancement of internal heat transfer in kiln, kiln shell loss reduction, optimize heat transfer in clinker cooler, use of waste fuels Blended cements, cogeneration... 

Site composite curves can be used to represent the site heating and cooling requirements thermodynamically. This allows the analysis of thermal loads and levels on site. Using the models for steam turbines and gas turbines allows cogeneration targets for the site to be established. Steam levels can be optimized to minimize fuel consumption or maximize cogeneration. A cost trade-off needs to be carried out in order to establish the optimum trade-off between fuel requirements and cogeneration. 

The optimization must focus on how much shaft work (or electricity) the cogeneration system should produce, given a specific product heat requirement, for present and future market conditions. The optimization must simultaneously locate the optimal capital investments, performance specifications, and operating characteristics for the system. 

The computational procedure used to optimize this Rankine cycle cogeneration system operates in one of two modes. When a... 

Comparison with Alternative and the Selection of Overall Optimum. The alternative to a cogeneration system is typically taken as a low pressure boiler or furnace, and purchasing electricity from the utility. It is when the economy of the optimally designed cogeneration system is compared to the alternative, that a system s true potential can be shown. 

A small fuel cell of about 1-kW in capacity, could cogenerate year-round to provide base-load power and hot water. Larger fuel cells would provide too much heat than a home can use most of the time. The DOE estimates that the optimal size for a residential combined heat and power (CHP) or cogeneration system in the United States is about 0.75-kW for a PEM fuel cell. 

Erlach, B., Tsatsaronis, G., and Cziesla, F., A new approach for assigning costs and fuels to cogeneration products. In ECOS ol, Efficiency, Costs, Optimization, Simulation and Environmental... 

Optimize compressor operation, reduce friction and air leakages in air distribution system, low pressure drop air coolers and instruments, reduction of air leaks, use of heat of compression dryers, cool compressor suction air, waste heat recovery at compressor inter-stage coolers, better control Install additional compressors in parallel. Use of heat of compression dryer Use cogeneration, ORC, KC or (hydraulic) power recovery turbines... 

No matter how much the steam system could be optimized, one relevant and important question is What is the maximal efficiency that the steam system can achieve The answer will be provided by the concept of cogeneration efficiency that is discussed next. 

Until now, we can safely derive the conclusion It is not always tme that maximal efficient operation is the most economical operation. It is tme only when words, the necessary and sufficient condition can be stated as When the PEE is higher than on-site power generation efficiency, the maximal efficient operating mode is also the minimal cost operating mode. Under this condition, the problem of optimizing the steam system is converted to a simplified problem to maximize the cogeneration efficiency. 

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