System and method for remediation of oil-contaminated sand

Abstract

The system and method for remediation of oil-contaminated sand provides for washing and separation of sand from oil and oil-based contamination. The system includes a feed hopper for receiving a volume of oil-contaminated sand in communication with a cleaning tank for receiving the volume of oil-contaminated sand therefrom. A mechanical stirrer mixes the volume of oil-contaminated sand with a surfactant solution in the cleaning tank. An ultrasonicator ultrasonicates the volume of oil-contaminated sand and the surfactant solution in the cleaning tank to create a mixture of washed sand and oily wastewater. A collection tank then receives the mixture. A band filter covers an open upper end of the collection tank, such that the mixture of washed sand and oily wastewater is filtered to separate out the washed sand, which may then be collected. The separated oily wastewater is then collected in the collection tank.

1 . A system for remediation of oil-contaminated sand, comprising:
 a feed hopper for receiving a volume of oil-contaminated sand;   a cleaning tank in communication with the feed hopper for receiving the volume of oil-contaminated sand from the feed hopper;   a mechanical stirrer in the cleaning tank for mixing the volume of oil-contaminated sand with a surfactant solution in the cleaning tank;   an ultrasonicator in the cleaning tank for ultrasonicating the volume of oil-contaminated sand and the surfactant solution in the cleaning tank to create a mixture of washed sand and oily wastewater;   a collection tank in communication with the cleaning tank, the collection tank having an open upper end and an outlet formed in a sidewall thereof; and   a band filter covering the open upper end of the collection tank, wherein the mixture of washed sand and oily wastewater is conveyed to the collection tank, the washed sand being filtered from the mixture by the band filter and the oily wastewater being collected in the collection tank.   
     
     
         2 . The system for remediation of oil-contaminated sand as recited in  claim 1 , further comprising a solid pump for feeding the volume of oil-contaminated sand into the feed hopper. 
     
     
         3 . The system for remediation of oil-contaminated sand as recited in  claim 2 , further comprising a conveyer belt extending between an outlet of the feed hopper and the cleaning tank for selectively transporting the volume of oil-contaminated sand from the feed hopper to the cleaning tank. 
     
     
         4 . The system for remediation of oil-contaminated sand as recited in  claim 3 , further comprising a sand receptacle in communication with the collection tank, the sand receptacle for receiving the washed sand filtered from the mixture by the band filter. 
     
     
         5 . The system for remediation of oil-contaminated sand as recited in  claim 1 , further comprising an aeration tank in communication with the outlet of the collection tank for receiving the oily wastewater for aeration thereof. 
     
     
         6 . The system for remediation of oil-contaminated sand as recited in  claim 5 , further comprising a coagulation tank in communication with the aeration tank for mixing the oily wastewater, following aeration thereof, with at least one coagulant for separation of the oily wastewater into treated water and an oily sludge. 
     
     
         7 . The system for remediation of oil-contaminated sand as recited in  claim 6 , further comprising a treated water tank for receiving the treated water. 
     
     
         8 . A system for remediation of oil-contaminated sand, comprising:
 a feed hopper for receiving a volume of oil-contaminated sand;   a cleaning tank in communication with the feed hopper for receiving the volume of oil-contaminated sand from the feed hopper;   a mechanical stirrer in the cleaning tank for mixing the volume of oil-contaminated sand with a surfactant solution in the cleaning tank;   an ultrasonicator in the cleaning tank for ultrasonicating the volume of oil-contaminated sand and the surfactant solution in the cleaning tank to create a mixture of washed sand and oily wastewater;   a collection tank in communication with the cleaning tank, the collection tank having an open upper end and an outlet formed in a sidewall thereof;   a band filter covering the open upper end of the collection tank, wherein the mixture of washed sand and oily wastewater is conveyed to the collection tank, the washed sand being filtered from the mixture by the band filter and the oily wastewater being collected in the collection tank;   an aeration tank in communication with the outlet of the collection tank for receiving the oily wastewater for aeration thereof; and   a coagulation tank in communication with the aeration tank for mixing the oily wastewater, following aeration thereof, with at least one coagulant for separation of the oily wastewater into treated water and an oily sludge.   
     
     
         9 . The system for remediation of oil-contaminated sand as recited in  claim 8 , further comprising a solid pump for feeding the volume of oil-contaminated sand into the feed hopper. 
     
     
         10 . The system for remediation of oil-contaminated sand as recited in  claim 9 , further comprising a conveyer belt extending between an outlet of the feed hopper and the cleaning tank for selectively transporting the volume of oil-contaminated sand from the feed hopper to the cleaning tank. 
     
     
         11 . The system for remediation of oil-contaminated sand as recited in  claim 10 , further comprising a sand receptacle in communication with the collection tank for receiving the washed sand filtered from the mixture by the band filter. 
     
     
         12 . The system for remediation of oil-contaminated sand as recited in  claim 11 , further comprising a treated water tank for receiving the treated water. 
     
     
         13 - 20 . (canceled) 
     
     
         21 . In a system for remediation of oil-contaminated sand, including a feed hopper, a collection tank, a band filter covering the open upper end of the collection tank, an aeration tank, and a coagulation tank, a cleaning apparatus, comprising:
 a cleaning tank in communication with the system between the feed hopper and the collection tank, the cleaning tank having an interior cylindrical wall defining a cylindrical chamber;   a liquid jetting system for introducing and recirculating a surfactant solution into the cylindrical chamber;   a mechanical stirrer disposed in the cleaning tank for mixing the volume of oil-contaminated sand with the surfactant solution in the cleaning tank;   a plurality of ultrasonic transducers mounted in the cleaning tank for ultrasonicating the volume of oil-contaminated sand and the surfactant solution in the cleaning tank to create a mixture of washed sand and oily wastewater;   wherein the plurality of ultrasonic transducers are uniformly distributed about the cylindrical chamber of the cleaning tank; and   wherein the feed hopper providing a volume of oil-contaminated sand to the cleaning tank, and the collection tank receiving a mixture of washed sand and oily wastewater via the band filter, the washed sand being filtered from the mixture by the band filter and the oily wastewater being collected in the collection tank.   
     
     
         22 . The system for remediation of oil-contaminated sand as recited in  claim 21 , the cleaning tank further comprising:
 a heater for maintaining the cylindrical chamber at a predetermined temperature for optimizing the cleaning operation; and   a control unit for selectively controlling the heater, the mechanical stirrer, and the plurality of ultrasonic transducers.   
     
     
         23 . The system for remediation of oil-contaminated sand as recited in  claim 21 , wherein the surfactant solution includes an aqueous saponin solution. 
     
     
         24 . The system for remediation of oil-contaminated sand as recited in  claim 21 , wherein the mechanical stirrer is designed and configured to agitate at a predetermined speed. 
     
     
         25 . The system for remediation of oil-contaminated sand as recited in  claim 21 , wherein the plurality of ultrasonic transducers being designed and configured to operate at a predetermined frequency, and the plurality of ultrasonic transducers are disposed in a vertical array. 
     
     
         26 . The system for remediation of oil-contaminated sand as recited in  claim 21 , wherein the liquid jetting system includes a flow pump and an in-line strainer.