US Patent 7967918 Low-pressure sludge removal method and apparatus using coherent jet nozzles

Provided area cleaning apparatus and an associated method of using the disclosed apparatus wherein the apparatus utilizes one or more nozzles configured to provide a coherent stream of one or more cleaning fluids for removing accumulated fine particulate matter, sludge, from surfaces. The nozzles may be sized, arranged and configured to provide coherent streams that maintain the initial stream diameter for a substantial portion of the maximum dimension of the space being cleaned. The apparatus and method are expected to be particularly useful in the cleaning of heat exchangers incorporating a plurality of substantially vertical and narrowly spaced tubes by directing cleansing streams along a plurality of intertube spaces.