Cogeneration of power

Boilers are operated in many industries for generating steam required for process heating of reactors, evaporators, and distillation columns which may need steam at a pressure of 4-6 kg/cm only. However, the boilers are generally operated at 10-15 kg/cm or even higher pressures. Steam is also available from waste heat recovery boilers in many chemical industries at such pressures. 

Extraction type turbine with/without reheat 

Steam-driven reciprocating engines (these have limited apphcations as their efficiency is low) 

Back pressure steam turbines are to be used instead of PRY The situation is ideal when all the steam can be passed through the turbine and then used for process heating. 

When steam is required at the process plant at different pressmes, the extraction-type steam turbine may be considered, wherein steam is extracted out from different stages, and the last stage exhausts at a pressme corresponding to the lowest pressure required in the plant. An accurate estimate of the consirmption pattern of steam is necessary for procitring the turbine with the right design and to operate it efficiently. 

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Sulfuric Acid Plant with Cogeneration of Power... 

In the present scenario there is a shortage of power. To circumvent this insufficiency, existing as well as new acid plants should have the provision of cogeneration of power. 

Cogeneration of Power Through Waste Heat Recovery Boilers and Economisers... 

Smaller HTR-Module plants can become competitive by the economical attractive cogeneration of power and steam or heat e.g. for refineries, chemical industry, district heating grids, tertiary oil recovery and more. 

Includes cogenerators, small power producers, and all other sources, except electric utiUties which produce electricity for self-use or for deUvery to the grid. The generation values for nonutiUties represent gross generation rather than net generation (net of station use). 

Boyce, M.P., Gabriles, G.A., and Meher-Homji, C.B., Enhancing System Availability and Performance in Combined Cycle Power Plants by the Use of Condition Monitoring, European Conference and Exhibition Cogeneration of Heat and Power, Athens, Greece, November 3-5, 1993. 

Figure 14-41 illustrates a couple of power capacity styles of gas turbine generators for providing the required hot gas to drive a power turbine connected to mechanical applications such as power generation, gas compression, cogeneration, oil pumping, and others. 

The process also has a requirement for 7 MW of power. Two alternative cogeneration schemes are to be compared economically. 

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