Treating Water

Abstract

Systems and methods for treating produced water and/or flowback water from fracking operations include: an oil water separator; a first filter downstream of the oil water separator; and an electrocoagulation unit downstream of the first filter. Systems and methods can be used for producing a concentrated brine for use in industrial applications and a separate stream of fresh water.

What is claimed is: 
     
         1 . A system for treating produced water and/or flowback water from fracking operations, the system comprising:
 an oil water separator;   a first filter downstream of the oil water separator; and   an electrocoagulation unit downstream of the first filter.   
     
     
         2 . The system of  claim 1 , wherein the oil water separator comprises a housing, a specific gravity section, a gas flotation system downstream of the specific gravity section, and the coalescing media pack downstream of the gas flotation system, wherein the specific gravity section, the gas flotation system, and the coalescing media pack are disposed within the housing. 
     
     
         3 . The system of  claim 2 , wherein the gas flotation system comprises a source of an oxygenated gas and a distribution element configured to impart the oxygenated gas into water being treated in the form of microbubbles. 
     
     
         4 . The system of  claim 3 , wherein the oxygenated gas comprises air. 
     
     
         5 . The system of  claim 3 , wherein the microbubbles have a characteristics size of between 5 and 50 microns. 
     
     
         6 . The system of  claim 1 , wherein the first filter comprises an oleophilic media. 
     
     
         7 . The system of  claim 1 , comprising a clarifier downstream of the electrocoagulation unit. 
     
     
         8 . The system of  claim 7 , comprising a reverse osmosis system downstream of the clarifier. 
     
     
         9 . The system of  claim 8 , comprising a second filter downstream of the clarifier and upstream of the reverse osmosis system. 
     
     
         10 . The system of  claim 8 , comprising an ion exchange system downstream of the clarifier and upstream of the reverse osmosis system. 
     
     
         11 . The system of  claim 7 , comprising a solids separation/concentration device disposed to receive solids from the clarifier. 
     
     
         12 . The system of  claim 11 , comprising piping providing a channel between an outlet of the solids separation/concentration device and an inlet of the oil water separator. 
     
     
         13 . A method of treating produced water and/or flowback water from fracking operations, the method comprising:
 separating oil from water being treated by using differences of specific gravity and then adding microbubbles of gas to the water being treated to lift material in the water being treated;   applying electrocoagulation to the water being treated after separating oil from the water being treated;   removing dissolved solids from the water being treated using ion exchange; and then   removing dissolved salts from the water being treated using reverse osmosis.   
     
     
         14 . The method of  claim 13 , wherein adding microbubbles of gas to the water being treated increases oxygen levels in the water being treated. 
     
     
         15 . The method of  claim 13 , wherein the ion exchange preferentially removes calcium, magnesium, and/or boron. 
     
     
         16 . The method of  claim 13 , wherein applying electrocoagulation to the water being treated creates oxides of at least some metals present in the water being treated and disassociates hydrocarbons and other organic materials. 
     
     
         17 . A method of producing a concentrated brine for use in industrial applications, the method comprising:
 introducing produced water into an oil water separator;   increasing oxygen levels in water being treated in the oil water separator;   applying electrocoagulation to the water discharged from the oil water separator;   concentrating dissolved salts in the water being treated using reverse osmosis to produce the concentrated brine; and   collecting the concentrated brine for use in industrial applications.   
     
     
         18 . The method of  claim 17 , wherein increasing oxygen levels in water being treated comprises adding microbubbles of dissolved air to the water being treated. 
     
     
         19 . The method of  claim 18 , comprising removing dissolved solids from the water being treated using ion exchange before concentrating dissolved salts in the water being treated using reverse osmosis. 
     
     
         20 . The method of  claim 19 , wherein removing dissolved solids from the water being treated using ion exchange comprises preferentially removing calcium and magnesium by ion exchange and then preferentially removing boron by ion exchange. 
     
     
         21 . The method of  claim 17 , wherein applying electrocoagulation to the water being treated creates oxides of boron present in the water being treated and disassociates hydrocarbons and other organic materials. 
     
     
         22 . The method of  claim 21 , wherein applying electrocoagulation to the water being treated creates oxides of metals other than boron present in the water being treated.