Abstract: Methods for cleaning at least one soiled substrate in a rotatably mounted cylindrical drum of a cleaning apparatus with a multiplicity of solid particles are provided. One method includes the steps of: agitating the at least one soiled substrate in the drum with wash liquor and the multiplicity of solid particles for a first cleaning cycle wherein the wash liquor includes at least one cleaning agent; draining the wash liquor from the cleaning apparatus; and introducing an aqueous non-detergent medium into the cleaning apparatus and agitating the at least one soiled substrate with the multiplicity of solid particles in the drum for a second cleaning cycle. Another method includes rotating the drum such that the at least one soiled substrate moves about a generally circular path and introducing the multiplicity of solid particles into the drum through an annulus defined by the generally circular path as the drum rotates.

Abstract: An apparatus for cleaning a soiled substrate using solid particulate material having a cleaning volume; a collecting volume; a pumping device having a pump inlet; and a circulation pathway by which solid particulate material and a transporting fluid can be transferred from the collecting volume to the cleaning volume via said pumping device. The apparatus further includes a flow regulating device disposed in the collecting volume and comprising a flow through enclosure defined by at least one wall, an enclosure outlet in communication with the pump inlet, at least one particle inlet orifice disposed at an underside of the flow through enclosure and configured to admit both solid particulate material and transporting fluid to the enclosure. The apparatus can further include at least one relatively smaller fluid inlet orifice configured only to admit transporting fluid to the flow through enclosure.

Abstract: A method for cleaning at least one soiled substrate in a rotatably mounted cylindrical drum of a cleaning apparatus with a multiplicity of solid particles comprising the steps of: a) agitating said at least one soiled substrate in said drum with wash liquor and said multiplicity of solid particles for a first cleaning cycle wherein said wash liquor comprises at least one cleaning agent; b) draining said wash liquor from said cleaning apparatus; and c) introducing an aqueous non-detergent medium into said cleaning apparatus and agitating said at least one soiled substrate with said multiplicity of solid particles in said drum for a second cleaning cycle.

Abstract: An apparatus for cleaning a soiled substrate using solid particulate material having a cleaning volume; a collecting volume; a pumping device having a pump inlet; and a circulation pathway by which solid particulate material and a transporting fluid can be transferred from the collecting volume to the cleaning volume via said pumping device. The apparatus further includes a flow regulating device disposed in the collecting volume and comprising a flow through enclosure defined by at least one wall, an enclosure outlet in communication with the pump inlet, at least one particle inlet orifice disposed at an underside of the flow through enclosure and configured to admit both solid particulate material and transporting fluid to the enclosure. The apparatus can further include at least one relatively smaller fluid inlet orifice configured only to admit transporting fluid to the flow through enclosure.