A cleaning vehicle generally has a grey water reservoir having a pre-filter; an aspiration conduit leading into the grey water reservoir upstream from the pre-filter and a vacuum pump adapted to create a vacuum inside the grey water reservoir to draw grey water; a vortex separation subsystem connected downstream from the pre-filter; a filtration bag subsystem connected downstream from the vortex separation subsystem; a filtrate reservoir connected downstream from the filtration bag subsystem; a high pressure hose having an end connected downstream from the filtrate reservoir and another end having a high pressure spray nozzle; a filtrate path extending from the grey water reservoir to the high pressure spray nozzle via the pre-filter, the vortex separation subsystem, the filtration bag subsystem and the high pressure hose; and at least one pump adapted to entrain a flow of fluid along the filtrate path.

A cleaning vehicle generally has a grey water reservoir having a pre-filter; an aspiration conduit leading into the grey water reservoir upstream from the pre-filter and a vacuum pump adapted to create a vacuum inside the grey water reservoir to draw grey water; a vortex separation subsystem connected downstream from the pre-filter; a filtration bag subsystem connected downstream from the vortex separation subsystem; a filtrate reservoir connected downstream from the filtration bag subsystem; a high pressure hose having an end connected downstream from the filtrate reservoir and another end having a high pressure spray nozzle; a filtrate path extending from the grey water reservoir to the high pressure spray nozzle via the pre-filter, the vortex separation subsystem, the filtration bag subsystem and the high pressure hose; and at least one pump adapted to entrain a flow of fluid along the filtrate path.

An apparatus for dewatering sludge comprises a tank having an internal space divided by a dividing wall into an intake chamber and an extract chamber, an intake pipe connected to the intake chamber by an intake valve, a discharge pipe connected to the extract chamber by a discharge valve, and a transfer pipe providing fluid communication between the intake chamber and the extract chamber. The transfer pipe has first opening near the bottom of the intake chamber, and a second opening near the top of the extract chamber. A pump selectively creates positive and negative pressure within the intake chamber. A screen is positioned within the extract chamber between the second opening of the transfer pipe and the discharge pipe.

A hydrovac unit with a mud tank and water tank arranged symmetrically, so that the center of gravity does not substantially shift forwards or backwards during operation. The mud tank may be located inside the water tank. The mud tank may be supported and reinforced by external ribs, which may be fixed to the mud tank. The water tank may be formed by a rear face attached to the mud tank and a cylinder portion, the mud tank and rear face sliding into the cylinder portion for assembly and secured in place. The contents of the hydrovac unit may be dumped by tilting using a hoist. The tank assembly may be heated and insulated.

A pump-storage device comprises a treatment container including an interior separated by a partitioning board into an upper chamber and a lower chamber intercommunicating with the upper chamber via a first intercommunication port. An inlet intercommunicates with the upper chamber. A second intercommunication port intercommunicates the lower chamber with an outside. A first control valve controls intercommunication between the upper and lower chambers. A second control valve controls intercommunication between the upper chamber and a gas suction source. An actuation rod extends through the first intercommunication port. A first fixing block, a second fixing block, and a third fixing block are mounted from top to bottom in sequence on the actuation rod. An upper stop plate is disposed between the first and second fixing blocks. A lower stop plate is disposed between the second and third fixing blocks. The upper and lower stop plates are elastically supported.

An apparatus for dewatering sludge comprises a tank having an internal space divided by a dividing wall into an intake chamber and an extract chamber, an intake pipe connected to the intake chamber by an intake valve, a discharge pipe connected to the extract chamber by a discharge valve, and a transfer pipe providing fluid communication between the intake chamber and the extract chamber. The transfer pipe has first opening near the bottom of the intake chamber, and a second opening near the top of the extract chamber. A pump selectively creates positive and negative pressure within the intake chamber. A screen is positioned within the extract chamber between the second opening of the transfer pipe and the discharge pipe.

An apparatus for dewatering sludge comprises a tank having an internal space divided by a dividing wall into an intake chamber and an extract chamber, an intake pipe connected to the intake chamber by an intake valve, a discharge pipe connected to the extract chamber by a discharge valve, and a transfer pipe providing fluid communication between the intake chamber and the extract chamber. The transfer pipe has first opening near the bottom of the intake chamber, and a second opening near the top of the extract chamber. A pump selectively creates positive and negative pressure within the intake chamber. A screen is positioned within the extract chamber between the second opening of the transfer pipe and the discharge pipe. —15—

A pump-storage device comprises a treatment container including an interior separated by a partitioning board into an upper chamber and a lower chamber intercommunicating with the upper chamber via a first intercommunication port. An inlet intercommunicates with the upper chamber. A second intercommunication port intercommunicates the lower chamber with an outside. A first control valve controls intercommunication between the upper and lower chambers. A second control valve controls intercommunication between the upper chamber and a gas suction source. An actuation rod extends through the first intercommunication port. A first fixing block, a second fixing block, and a third fixing block are mounted from top to bottom in sequence on the actuation rod. An upper stop plate is disposed between the first and second fixing blocks. A lower stop plate is disposed between the second and third fixing blocks. The upper and lower stop plates are elastically supported.

A hydrovac unit with a mud tank and water tank arranged symmetrically, so that the center of gravity does not substantially shift forwards or backwards during operation. The mud tank may be located inside the water tank. The mud tank may be supported and reinforced by external ribs, which may be fixed to the mud tank. The water tank may be formed by a rear face attached to the mud tank and a cylinder portion, the mud tank and rear face sliding into the cylinder portion for assembly and secured in place. The contents of the hydrovac unit may be dumped by tilting using a hoist. The tank assembly may be heated and insulated.

A service mode selection system for a service vehicle is provided for simplifying a control for setting the vehicle in a desired service mode. The system includes a control system for receiving an operator's selection of service mode via a service mode selection device and controlling vehicle components to automatically set the vehicle in a selected service mode. The service mode selection device can be arranged in a cab of the vehicle and allows the operator to conveniently select a desired service mode, thereby achieving a work-ready machine with as few operator inputs as possible.