Product cogenerated

These are briefly reviewed, followed by summary economics for the production from wood of electricity, steam, and cogenerated products intermediate-Btu gas (IBG) and substitute natural gas (SNG) methanol ammonia fuel oil and pyrolytic oil and char. Several processing steps in these conversion schemes are conceptual or are at early stages of development by DOE, EPRI, GRI, and others (an exception would be wood steam/electric power plants, which are commercially used by the electric utility and wood products industries). Consequently, the economics presented here may generally tend to be optimistic. Additional details of the analyses can be found in Kohan and Barkhordar(1) Jones, Kohan and Semrau(2J and Kohan and Dickenson( 3). ... 

Table II shows the estimated revenue requirements. Electricity and cogenerated products costs are based on regulated utility financing, while steam costs are based on non-regulated industrial financing. The cogeneration case costs are shown on a total product basis, since two products are involved. Figure 1 shows the selling price of electricity as a function of the selling price of steam for the cogeneration case.

CO2 emission reduction effects in cogeneration production were calculated by adapting formulas from Directive 2004/8/EC. 

In a decision taken in March 2005 the Commission accepted the cap level of 239 Mt/year which is 16.5 % below the Polish proposal. This decision was based on the Commission s revision of emission projections and its refusal to accept the allocation of additional allowances above the projections to assign benefits for significant early action and cogeneration production and to compensate main risk factors. 

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... 

Cogeneration products such as power, steam, hot air, or hot water cannot be sold during the plant shutdown. 

Chronoiogicai improvements in stack durabiiity based on annuai automotive duty cycie iaboratory demonstration tests and hot water/ eiectricai cogeneration stack product iterations (API, AP2 and 1030V3 indicate successive product names in the cogeneration product iine). 

The principal sources of utility waste are associated with hot utilities (including cogeneration) and cold utilities. Furnaces, steam boilers, gas turbines, and diesel engines all produce waste as gaseous c bustion products. These combustion products contain carbon... 

Alternatively, short-rotation hybrid poplar and selected grasses can be multicropped on an energy plantation in the U.S. Northwest and harvested for conversion to Hquid transportation fuels and cogenerated power for on-site use in a centrally located conversion plant. The salable products are Hquid biofuels and surplus steam and electric power. This type of design may be especially useful for larger land-based systems. 

Table 34. Biomass-Fueled Cogeneration and Small Power Production Capacities and Facilities, kW ...

Cog enera.tion in a. Steam System. The value of energy in a process stream can always be estimated from the theoretical work potential, ie, the deterrnination of how much power can be obtained by miming an ideal cycle between the actual temperature and the rejection temperature. However, in a steam system a more tangible approach is possible, because steam at high pressure can be let down through a turbine for power. The shaft work developed by the turbine is sometimes referred to as by-product power, and the process is referred to as cogeneration. 

Typical Systems All cogeneration systems involve the operation of a heat engine for the production or mechanical work hich, in nearly all cases, is used to di ive an electric generator. The commonest heat-engine types appropriate for topping-cycle cogeneration systems are ... 

The coke oven gas is cooled, and by-products are recovered. Flushing liquor, formed from the cooling of coke oven gas, and liquor from primary coolers contain tar and are sent to a tar decanter. Note that the coke oven gas has a heating value and can be used effectively in the cogeneration of heat or electricity, which can be used by the plant, or if available in sufficient quantities, can be sold into local grids. 

An explosion and fire (March 13, 1991) occurred at an ethylene oxide unit at Union Carbide Chemicals Plastics Co. s Seadrift plant in Port Lavaca, TX, 125 miles southwest of Houston. The blast killed one, injured 19, and idled the facility, that also produces ethylene, ethylene glycol, glycol ether ethanolamines, and polyethylene. Twenty-five residents were evacuated for several hours as a safety precaution. The plant lost all electrical power, for a few days, because its cogeneration unit was damaged. The Seadrift plant, with 1,600 workers, is capable of making 820 million lb per year of ethylene oxide which is one-third of Carbide s worldwide production of antifreeze, polyester fibers, and surfactants Seadrift produces two thirds of Carbide s worldwide production of polyethylene. 

Fig. 9.2 shows how a simple open circuit gas turbine can be used as a cogeneration plant (a) with a waste heat recuperator (WHR) and (b) with a waste heat boiler (WHB). Since the products from combustion have excess air, supplementary fuel may be burnt downstream of the turbine in the second case. In these illustrations, the overall efficiency of the gas turbine is taken to be quite low ((tjo)cg = ccJf ca 0.25), where the subscript CG indicates that the gas turbine is used as a recuperative cogeneration plant. 

Cogeneration is the production of two useful forms of energy in a single energy conversion process. For example, a gas turbine may produce both rotational energy for an electric generator and heat for a building. 

Spiewak, S. A., and Weiss, L. (1994). Cogeneration and Small Power Production Manual, 4th ed. Liburn, GA Fairmont Press. 

Cogeneration encompasses several distinct thermodynamic processes of simultaneous heat and power production. One utilizes air as a medium, another steam, a third employs heat rejected from a separate combustion process, such as an internal-combustion engine, and a fourth utilizes a thermochemical process such as found in a fuel cell. Although each process is distinct, they are often combined together to inaxiniize the energy production in a single thermodynamic system. 

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