TECHNICAL FIELD

This disclosure relates generally to an apparatus for automated separation of the gas from a supply of a mixture of gas and liquid and particle contaminants. The automated separator system includes a gas scrubber having a separator and programmable logic controller that causes release of unwanted contaminants and liquids when certain user defined conditions are met. The gas separated from the mixture is directed to a flare stack or other source and the separated liquid and contaminant mixture is directed to a storage facility.

DESCRIPTION OF RELATED ART

Oil and gas exploration and drilling entails extraction of the resource from a subterranean formation as it flows to the earth's surface. The oil or natural gas is then collected at the well site. Often, unusable natural gas that contains primarily hydrocarbons, is also collected at drilling or testing sites. This natural gas commonly includes entrained water that is typically in the form of water vapor. Depending on the source, the natural gas may also include pollutants and other contaminants. Exploration entities must often dispose of the waste gas by burning it through a flare stack operated at the well site. The burning off of the waste gas is necessary as accumulation of the gas poses significant safety and environmental concerns.

The presence of natural gas with entrained water presents various problems common to the use, storage, transportation and further extraction of the gas. At cooler surface temperatures and decreased vapor pressure, the water vapor condenses into liquid. The presence of entrained water is undesirable and causes problems in pipeline and process equipment including corrosion. Collection areas in equipment and pipelines are common and at these places water collects and freezes into an ice, which is particularly problematic as drilling is common in places with cold climates. Frozen water in pipes results in partial or full restriction of gas flow through a line. In the gas exploration industry, therefore, various techniques have been employed to extract as much of the entrained water as possible from the natural gas or oil during extraction process.

One such process employed in the natural gas exploration industry to extract water from natural gas is through liquid dehydrators. Through this process, the natural gas including entrained water is directed into a vessel, often referred to as a scrubber. In the vessel, a separator is situated at a level above the point of entry of the liquid into the vessel. The separator retains the liquid present in the vapor as the wanted gas vapor (for further processing, transportation, or disposing by a flare) rises above the separator and is ultimately directed towards the target location. The “dry” natural gas can is then passed to a pipeline for storage or use.

At the same time, the byproduct of the separation process is a wet substance consisting primarily of water that is directed to a separate storage tank or facility for further processing or disposal. In the alternative, this remaining “liquid gas” may be re-introduced to the scrubber for additional extraction of vapor for burning or use.

The vapor and liquid components of the “wet” gas cannot simply be released into the environment or disposed of. The vapor component remaining after extraction of the entrained liquid is a pollutant that is usually burned off by a flare to minimize the negative effects of introducing the vapor to the environment. Similarly, the water remaining after the separation process is not “pure” water and invariably contains remnants of materials that impact negatively the environment. As such, the liquid remainder must be disposed of in tanks or other receptacles for removal or further processing. Enactment of environmental laws as the state and federal level require that the introduction of these pollutants to the atmosphere be minimized or eliminated altogether.

Following the process described above performed by the scrubber to separate the liquid and vapor of natural but perhaps unusable natural gas encountered during oil and gas extraction, the problem of monitoring and maintaining the scrubber in a safe manner persists. Operators of scrubbers must account for removing of the liquid residual after separation. They are limited, however, in terms of the frequency in which the scrubber vessel may be emptied and the size of the scrubber. As such, constant draining of the vessel is futile because separation is a relatively gradual process and none will occur if the scrubber acts as a virtual sieve. Similarly, the typical vessel holds a relatively small amount of liquid. For effective operation of the scrubber, the level of liquid within a lower chamber of the vessel should not rise to the level of the separation means. As such, a relatively small amount of liquid may be contained in the vessel. Operators are, therefore, required to empty the vessel at regular intervals to maintain effective separation by the scrubber.

Regular emptying of the scrubber vessel is also required to prevent overflow of the vessel that will cause flammable and environmentally hazardous liquid to spill on the ground. Moreover, preventing the entrained gas from permeating lines to a flare or other equipment is necessary to prevent damage to equipment or uncontrolled fire, for example, in or around other combustible materials or in areas in which a pilot or other ignition means exists. As a practical matter, scrubber vessels may be in use at remove locations where personnel may not be available to regularly remove or drain liquid from the vessel. Similarly, personnel that are present and responsible for maintaining the scrubber may be tasked elsewhere and scrubber emptying may be a low priority as compared to other tasks or forgotten. As such, scrubber vessels may overflow or be emptied in a hurried manner on the ground or sloppily causing spillage of the environmentally hazardous liquid. Perhaps worse, highly flammable liquid will permeate areas that if ignited may cause serious equipment damage or production or extraction delays or human injury or death.

The present inventions provides an automated vapor and liquid separator that eliminates the need for constant human intervention and monitoring to provide effective operation of the gas scrubber.

