Fuel equivalent cooling water

In March 1979 one of the nuclear reactor plants at the Three Mile Island (TMI) site (in Pennsylvania) had an equipment failure that led to a loss of cooling water from the reactor core. Operator errors compounded this mechanical malfunction, resulting in the destruction of most of the reactor core and melting some of the fuel. In spite of the extensive damage, the nuclear reaction was stopped and very little radiation was released to the environment. In fact, no person off site received more than a few millirem (equivalent to a few days background exposure) and no person on site exceeded their annual dose limit of 5 rem. This was not known at first, however, and the governor of Pennsylvania ordered the evacuation of many people from the area. 

In most cases, Qf ei is calculated based on the lower heating value of fuel. G,- is quantified in different units according to specifications in the marketplace, namely, Btu/h for fuel, Ib/h for steam, and kWh for power. Thus, specific FE factors can be developed as follows based on this general definition of fuel equivalent. Energy are required for making boiler feed water (BFW), condensate and cooling water. The FE factors for these utilities will be discussed in Chapter 3. 

Generally, evaporation of liquid water is an important mechanism of fuel cell cooling and the evaporation term should be added to the right-hand side of Equation 4.282. For simplicity, in this section, evaporation will be ignored, which is equivalent to the assumption that the water vapor pressure in the CCL is equal to the saturated pressure. Thus, solution to Equation 4.282 gives a maximal heat flux from the CCL, which is of large interest for cell and stack modeling. 

Besides the cost of the 02, there are other potential operating costs that may need to be considered. There may be minor maintenance requirements for the oxygen equipment. However, this should be comparable with an equivalent air/fuel system. If the bumer(s) or injection lance(s) needs water cooling, there may be some costs associated with the water. 

A major distinction between the use of carbon dioxide as an extinguishing agent and the Halon systems described in earlier sections is that the extinguishing mode for carbon dioxide is primarily simple smothering of the burning fuel, with no chemical action involved. There is tittle cooling action, with an effectiveness for carbon dioxide of about one tenth that of an equivalent amount of water. As a result, once the carbon dioxide has dissipated, the possibility of reignition exists if there are any sufficiently hot areas still present. 

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