Systems and Methods for Removing Volatile Compounds from Water-Storage Tanks

Abstract

A system for reducing an amount of volatile organic compounds which includes: a water-storage tank having a tank containing water, a roof positioned over the tank, and a headspace region formed between the roof and a surface of the water contained in the tank; an air exchange system positioned at least partially in the headspace region that is configured to exchange air exterior to the tank with air inside the tank; and a water conveyance device located at least partially in the water of the water-storage tank and which is configured to convey water in a manner that produces a surface flow velocity. A method reducing an amount of volatile organic compounds is also included.

What is claimed is: 
     
         1 . A system for reducing an amount of volatile organic compounds comprising:
 a water-storage tank comprising a tank containing water, a roof positioned over the tank, and a headspace region formed between the roof and a surface of the water contained in the tank;   an air exchange system positioned at least partially in the headspace region that is configured to exchange air exterior to the tank with air inside the tank; and   a water conveyance device located at least partially in the water of the water-storage tank and which is configured to convey water in a manner that produces a surface flow velocity,   wherein the air exchange system comprises an active air ventilation device configured to facilitate the movement of air exterior of the water-storage tank directly into the headspace region above the surface of the water, and   wherein the active air ventilation device comprises a deflector that deflects the air exterior of the water-storage tank entering the headspace region in a direction that is non-perpendicular to the water surface.   
     
     
         2 . The system of  claim 1 , wherein the water conveyance device is configured to convey water to the water surface. 
     
     
         3 . The system of  claim 1 , wherein the tank has a floor and the water conveyance device is configured to exchange water at or toward the floor of the tank with water at or toward the water surface. 
     
     
         4 . The system of  claim 3 , wherein the water conveyance device circulates water around the tank. 
     
     
         5 . The system of  claim 1 , wherein the water conveyance device is completely submerged in the water when the tank is in use. 
     
     
         6 . The system of  claim 5 , wherein the water conveyance device is attached to or sits upon the floor of the tank. 
     
     
         7 . The system of  claim 1 , wherein the air exchange system comprises a port that enables air to flow out of the water-storage tank. 
     
     
         8 . The system of  claim 1 , wherein the active air ventilation device is configured to facilitate the movement of air exterior of the water-storage tank into the headspace region substantially across the water surface. 
     
     
         9 . The system of  claim 1 , wherein the active air ventilation device comprises air vents that fluidly connect the air exterior of the water-storage tank to the headspace region. 
     
     
         10 . The system of  claim 9 , wherein the active air ventilation device comprises at least one screen that is positioned over at least one of the air vents. 
     
     
         11 . The system of  claim 1 , wherein the active air ventilation device comprises an air moving device. 
     
     
         12 . The system of  claim 11 , wherein the air moving device is a fan. 
     
     
         13 . The system of  claim 1 , wherein the water conveyance device comprises a mixer having blades. 
     
     
         14 . The system of  claim 11 , wherein the deflector is in fluid communication with the air moving device.