Patent ID: 7846331

Claim:
A vacuum truck comprising: a truck frame mounted on ground wheels; a vacuum pump mounted on the truck frame for generating an air flow through the pump to form a vacuum inlet on one side of the pump and an air outlet on an opposed side of the pump; a vacuum hose having an inlet nozzle for communicating air flow from a material to be vacuumed to carry the material in the air flow to a hose outlet; a storage tank having a tank inlet connected to the hose outlet of the vacuum hose for receiving the material carried in the air flow; at least one tank extraction outlet connected by a duct to the vacuum inlet of the pump such that air flow is drawn from the tank by the vacuum pump through the duct which generates the air flow in the vacuum hose to carry the material; the tank being arranged such that the materials carried in the airflow are discharged from the airflow as the airflow passes through the tank from the vacuum hose to the tank extraction outlet; the tank including a separation system therein for separating the materials generally into a liquid component and a solids component; a liquid pump mounted in the tank for extracting the separated liquid component from the tank to increase a storage capacity of the tank for the solids component to be collected and transported in the tank on the truck to a remote location for discharge; a discharge door at one end of the tank for discharging the collected solids component; a lifting arrangement for tilting the tank so as to discharge the collected solids component through the discharge door; the separation system including a generally upstanding dividing wall across the tank dividing a solids collection area on one side from a liquid collection area on the other side, with the solids collection area being located adjacent the discharge door, with the water pump having an inlet located in the liquid collection area and with the tank inlet located in the solids collection area; the dividing wall having a bottom wall portion, which is substantially imperforate and has a top edge at or adjacent a weir over which liquid can flow into the liquid collection area; the dividing wall having an upper screening section, which is perforated to allow the liquid to pass over the top edge into the liquid collection area while restricting passage of the solids; wherein the upper screening section includes a hanging curtain formed by a series of side by side lengths of chain.