REDUCED EMISSION SOLUTIONS
IN ALL MAJOR OPERATING REGIONS IN THE USA
DHI Vapor Tight Storage and Flowback Tanks
Green Flowback and Storage Tanks
The vapor tight tanks are all designed to hold a pressure of 16 oz/sq.in pressure which is considered a positive pressure atmospheric tank. The pressure relief systems supplied by DHI is typically set at 10 oz/sq.in venting to atmosphere. The tanks are to be normally vented via a 4” line to a larger diameter flare header flowing to a combustion flare/burner or atmospheric diffuser, in some case vapor recovery equipment may be employed to further reduce emissions.
This vent flowline needs to be be equipped with devices to prevent any flame blowback into the tanks caused by any pressure under balance (flame arrest device) by tank fluid evacuation or any other activity.
The tanks are equipped with access man ways that must be kept closed at all times when in use. The “Green Completion” tanks provide ways to minimize on site emissions to the lowest possible level.
Pressure Vacuum Protection
The purpose of the thief hatch is to work in tandem with the vent valve to minimize the escape of light
ends of crude in lease storage by maintaining a pressure on the tank. A vacuum relief function is also
standard to prevent a suction or draw down from collapsing the tank. The thief hatch permits access
to the contents of the tank for sampling and gauging.
The diffusers often referred to as “Gas Buster” installed in the flowback tanks permit the violent flowback of gas, oil, water, accompanied by solids and debris to depressurize harmlessly and drop into the tank for collection.
The DHI design eliminates the opportunity of any projectiles causing damage to the tank or tank liner while giving the gas a clean break from liquids to be vented with less suspended liquids. This reduction in mist reduces the possibility of smoke at the flare and makes these oil components recoverable.