A number of systems exist for dehydrating natural gas to remove water and other liquids from natural gas. Most of these dehydration systems involve passing the natural gas through or in contact with one of a number of known desiccant fluids, such as glycol. For brevity, the desiccant fluid may hereinafter be referred to as glycol, but it should be understood that glycol is only one exemplary desiccant fluid that may be used with such a system. The glycol essentially absorbs the water and other liquids from the natural gas, after which, natural gas is removed from the dehydration system to be sold, or otherwise utilized, and the “wet” glycol is cycled through the system to be regenerated or returned to a “dry” state in which it can be reused to dehydrate more natural gas.
The water and other liquids absorbed by the desiccant often include an amount of off-gases containing contaminants such as volatile organic compounds, known in the art as VOC's, and/or aromatic hydrocarbons, known in the art as BTEX. Such off-gases may be in a gaseous state suspended in the water or other liquids, or may be in liquid state, depending upon temperature, pressure, and/or other conditions. These off-gases are generally pollutants which should not be, and in many cases, may not legally be, released into the environment. These off-gases are generally flammable as well.
A number of attempts have been made to find methods for storing and disposing of such off-gases to prevent them from contaminating the environment. Storage methods may involve routing the off-gases to a tank where they can be held for later disposal. Well sites are often in remote locations, however, where it can be difficult, time-consuming, and expensive to periodically retrieve the off-gases for disposal. Additionally, storage tanks may corrode and begin to leak over time.
Disposal methods have included flares and re-boilers to burn the off-gases, reducing them to combustion byproducts that can more safely be released into the atmosphere. Problems remain, however, for such systems. For example, the off-gases are often mixed in a burner assembly with fuel gas. If the off-gases enter, and collect in, the burner assembly before the burner assembly is properly ignited so as to cause the off-gases to be drawn down to the tip of the burner assembly, a flash back fire may be created upon the ignition of the burner assembly.
To this end, a need exists for a dependable system and method that delays the delivery of the off-gases before they reach the burner assembly until the burner assembly is ignited and brought up to speed. It is to such system and method that the Inventive concepts disclosed herein are directed.
USPTO Backgrounds
USPTO Backgrounds