has not been discussed it is appropriate to do so at this point in the examination of the scheme of things normally contaminated perc enters the still 36 from path 56 and in the instant invention also from path 64 and is boiled of to a high degree in a conventional manner by heat supplied by hot steam from boiler 721 to heat exchanger 70 the boiled off perc leaves the still 36 and is returned to the cleaning cycle via path 38 as previously described at some point in this portion of the perc reclaiming cycle the still will become sufficiently loaded with muck high concentrated contaminate and perc mixed together wherein the concentration of muck is so high that the distillation process is no longer effective or efficient in order to efficiently reclaim the perc from this highly contaminated state live steam is normally allowed to enter the still 36 via path 74 and valve 76 dissolve and mix with the perc and re condense in perc condenser 34 while excessive water is dumped in sewer or bucket 80 this portion of the process is commonly referred to in the art as sweeping the still and must be regularly carry out by the operator of the system when the filtering cartridges are determined to be filled to capacity with contaminate so as to longer be useful in the conventional system they are removed discarded and replaced with fresh cartridges it is to be noted that every time the cartridges are replaced a significant amount of perc remains left in each cartridge and is there by lost from the system it might also be.