Patent Number: 042773610
Section: description

DESCRIPTION OF A PREFERRED EMBODIMENT Referring to FIG. 1, a reprocessing plant 210 includes a building 211 having side walls 212 and a roof 214 and a foundation 223. A vehicle access zone 215 permits mobile cranes 233 to move about on the covers 222 over compartments 221 arranged as an array of compartments 220, such as a rectangular array. A cover 222 is supported on a ledge 225 of a compartment wall 224. Openings 226 in vertical walls 224 permit communication lines 230 to extend from a compartment 221 to an appropriate zone. The compartment 221 has a support floor 227 on which processing equipment 232 can be mounted. A detection system in a sump 228 monitors for leaks. When desired, drainage systems can conduct liquids from sump to a remote storage system. It might sometimes be appropriate to provide an annular storage tank for emergency storage of liquid drained from the sump. As shown in FIG. 2, an air processing facility 240 includes a fan 241 and a series of specialized filters 242a, 242b, and heat exchangers 243 for cleaning and cooling the air supplied to fan 241. Air is withdrawn from compartments containing process equipment 232 through a return duct 245 and directed to filters 242a, 242b, and to heat exchanger 243 adapted to cool the air prior to supply to the fan 241. A recirculating air duct 246 directs the air from fan 241 to compartment 220. The covers 222 fit over compartments 221 in such a manner that some leakage is likely to occur even when the covers are not removed for a period of more than a year. The air pressure in the vehicle access zone 215 is greater than the pressure in compartment 221 whereby any air leakage that does occur tends to be from the vehicle access zone to the compartment rather than the other direction. The fan 241 maintains an air circulation of the air inventory of compartment 221 so that the air in compartment 221 can be treated as a quasi-hermetically sealed inventory of gas. The gas turnover rate is greater than one day but less than a year. Communication lines 230a, 230b, connect conduits 230c and 230d with process equipment 232. A system of interconnected conduits and manifolds 250 direct dirty air to a central air cleaner of the reprocessing plant 210. Air is discharged from recirculating duct 246 in each air processing facility 240 to the central air cleaner manifold system 250 through the exhaust line 251 for maintaining the quasi-hermetic seal of compartment 221 so that the air turnover rate is more than a day but less than a year. A turnover rate control 253 serves as a master control for maintaining the air circulation turnover rate within the range from about one day to about one year while also adjusting the pressure in compartment 221 so that often it is slightly less than the air pressure in the vehicle access zone 215. An air inlet 247 is connected to an air supply line 249 through a regulating valve 248 actuated by turnover rate control 253. A regulating valve 252 in exhaust line 251 (from facility 240 to manifold 250) is actuated by turnover rate control 253. The schematic showing of FIG. 2 is concerned with the quasi-hermatic sealing of a particular compartment 221 and its interrelationship with its air processing facility 240. It should be recognized that each of the compartments in which there is equipment 232 for the processing of the compositions derived from the depleted fuel rods has its own air processing facility 240. The total reprocessing plant 210 includes a considerable variety of such compartments 221 having their corresponding air processing facilities 240. As shown in FIG. 3, a reprocessing plant 310 can have a flow sheet in which there are communication lines 330 amongst compartments 320a, 320b, etc., 320m, each containing processing apparatus. An air processing facility 340a, 340b, etc., 340m is associated with corresponding compartments 320, containing processing equipment. As shown in connection with 320, a return duct 345c can direct the air from the compartment 320c to the air processing unit 340c and the cooled and/or filtered air can be returned to the compartment through recirculating air duct 346c. Fresh air through line 347 can be supplied to an air processing facility 340 in response to signals from control system 353. Each compartment is maintained at a controlled differential pressure less than that of the nearby zone, ordinarily the vehicle access zone. Moreover, each control 353 regulates the gas exhaust rate so that the gas turnover in its compartment is more than a day but less than a year. The stale air is discharged from the air processing unit 340 to a manifold 350 and thence to a central air cleaner 360. Clean air is discharged to the atmosphere through a vent 361. Various modifications of the invention are possible without departing from the scope of the appended claims.