Systems and methods for treating oilfield wastewater

A mobile wastewater treatment system, comprising:

• at least one mobile trailer or movable skid;
• a desanding hydrocyclone and a deoiling hydrocyclone mounted on said at least one mobile trailer or movable skid, wherein said desanding hydrocyclone and said deoiling hydrocyclone are adapted to receive a flow of wastewater;
• an electrocoagulation apparatus and a floc separator mounted on said at least one mobile trailer or movable skid, wherein said electrocoagulation apparatus is adapted to receive a flow of a substantially desanded and deoiled effluent exiting one of said desanding hydrocyclone and said deoiling hydrocyclone, and wherein said floc separator is adapted to remove agglomerated solids from a flow of an effluent exiting said electrocoagulation apparatus;
• and
• an ultrafiltration membrane apparatus mounted on said at least one mobile trailer or movable skid, wherein said ultrafiltration membrane apparatus is adapted to remove solids particles from at least a portion of a flow of an effluent exiting said floc separator.

A method of treating wastewater with a wastewater treatment system, the method comprising:

• directing a flow of wastewater to said wastewater treatment system;
• separating hydrocarbons and first solids particles from said flow of wastewater with first and second hydrocyclones of said wastewater treatment system;
• treating a flow of a first effluent exiting one of said first and second hydrocyclones in an electrocoagulation apparatus of said wastewater treatment system so as to form agglomerated solids from waste material present in said flow of said first effluent;
• removing said agglomerated solids from a flow of a second effluent exiting said electrocoagulation apparatus with a floc separator of said wastewater treatment system;
• and
• separating second solids particles from at least a portion of a flow of a third effluent exiting said floc separator in an ultrafiltration membrane apparatus of said wastewater treatment system.