Patent ID: 9062546
Filing Date: 2015-06-23
Classification: E21B,F24H,F28D

Abstract:
1. A method for heating treatment fluid at a remote work site to conduct hydraulic fracturing operations on a well, comprising: drawing treatment fluid from a fluid source; pumping said treatment fluid through a single pass of a heat exchanger, said heat exchanger comprising a tubular coil having a single inlet and a single outlet and being contained within a closed-bottom firebox having an exhaust stack configured near the top of said firebox, wherein said tubular coil includes an upper portion oriented about a first axis and a lower portion oriented about a second axis, said lower portion comprising a helical coil oriented about a horizontal axis so as to define a combustion chamber for receiving a substantially horizontal combustion flow, said combustion chamber being substantially enclosed by said helical tubular coil on all but one opened side, said helical coil including a plurality of traversing lateral tubes which substantially enclose said combustion chamber on a side opposing said opened side, wherein at least one of said traversing lateral tubes is configured directly in line with said substantially horizontal combustion flow; supplying a first pressurized air flow to a plurality of burner assemblies configured in said firebox by fluidly connecting a blower pump to a primary air inlet of each of said plurality of burner assemblies, wherein said blower pump comprises a positive displacement rotary blower; supplying a pressurized liquid fuel flow to said plurality of burner assemblies; heating said treatment fluid during said single pass through said heat exchanger by combusting an air-fuel mixture in said heat exchanger using said plurality of burner assemblies, wherein each of said burner assemblies combines said liquid fuel flow and first pressurized air flow to project an atomized fuel-air spray, which when combusted results in a substantially horizontal combustion flow into said combustion chamber; supplying a second pressurized air flow to a ductwork fluidly connected to said firebox, wherein said second air flow increases the convective heat transfer of thermal energy from said combustion flow to said treatment fluid as said fluid is pumped through said heat exchanger; wherein said treatment fluid is heated to a temperature not greater than 210° F. in ambient atmospheric temperatures below 25° F. while pumping through said heat exchanger at volumetric flow rate of at least 200 gpm.