Clean Process Technology for Utility Systems

Global emissions = (Emissions from on-site utilities) 

This is particularly important when considering the effect that cogeneration has on utility waste. 

The waste streams created by utility systems tend, on the whole, to be less environmentally harmful than process waste. Unfortunately, complacency would be misplaced. Even though utility waste tends to be less harmful than process waste, the quantities of utility waste tend to be larger than process waste. This sheer volume can then result in greater environmental impact than process waste. Gaseous combustion products contribute in various ways to the greenhouse effect, acid rain and can produce a direct health hazard because of the formation of smog. The aqueous waste generated by utility systems can also be a major problem if it is contaminated. 

Energy efficiency of the process. If the process requires a furnace or steam boiler to provide hot utility, then any 

Fuel switch. The choice of fuel used in furnaces and steam boilers has a major effect on the gaseous utility waste from products of combustion. For example, a switch from coal to natural gas in a steam boiler can lead to a reduction in carbon dioxide emissions of typically 40% for the same heat released9. This results from the lower carbon content of the natural gas. In addition, it is likely that the switch from coal to natural gas will also lead to a considerable reduction in both SO and NO emissions. 

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