Natural gas is normally saturated with water and if the water is not removed, it can condense out and freeze in the piping. This can often cause plugging and corrosion. To avoid these problems, the produced gas is commonly sent through a glycol dehydrator, where it goes through triethylene glycol (TEG), a dewatering agent, eliminating the moisture in the gas. Glycol dehydrators vent methane and other contaminants into the atmosphere such as volatile organic compounds (VOCs), Green House Gasses (GHG), and hazardous air pollutants (HAPs).
Numerous studies from economic and environmental agencies, like the EPA (the United States Environmental Protection Agency), tell us that replacing a glycol dehydrator with a deliquescent desiccant dehydrator can economically perform better and eliminate emissions. Transitioning to deliquescent desiccant dehydrators will save consumers thousands of dollars per year in fuel gas, vented gas, and maintenance costs. As the industry leader in deliquescent desiccant technology, Van Air Systems designed the PLD (Pipeline Deliquescent) Dryer to be an economical and effective solution for natural gas dehydration, completely eliminating atmospheric emissions. The PLD will instantly bring you back into compliance with EPA emissions regulations and prevent your natural gas production unit from being throttled back.
The amount of emissions put into the atmosphere has always been a concern. Typically, the higher the pressure, the more produced gas and money the company makes. Recently, the EPA is throttling the production of Natural Gas (NG) with glycol dehydrators because of short-lived climate pollutants –- such as black carbon, methane, and hydrofluorocarbons -– that are produced as emissions when using TEG dehydration units. Taking a look at the flow process of a TEG dehydration unit shows all the places where these emissions or short-lived pollutants (methane) can be released into the atmosphere during the dehydration process of a TEG dehydrator.
Photo: Natural Gas STAR
Because TEG dehydration units are one of the most popular options when it comes to natural gas production, the EPA is beginning to inform manufacturers that if emissions aren’t reduced, companies will be forced to reduce operating pressures to reduce emissions.
For example, let’s say that Company A has the capability to be running at 700 psig. The EPA informs Company A that due to Title 5 of the Clean Air Act of 2016, they couldn’t exceed 350 psig (equated to 200,000 SCFD) because emissions at higher pressures would exceed the allowable limits. Company A now must run their heater/reboiler, which increases overall rates/costs. Each application is different when it comes to the exact increase in flow that is allowed based on the EPA’s guidelines because it is a function of pressure and temperature. However, one thing always remains constant for manufacturers; at higher pressures producers can achieve higher flows, which then equals more money.
With TEG dehydration units, these short-lived pollutants are powerful climate forcers that significantly impact food, water, and economic security for large populations throughout the world. Because of this threat, the EPA is trying to mitigate these short-lived climate pollutant emissions to decrease negative, and potentially irreversible, consequences for global warming. Below is a diagram that describes how much methane TEG Dehydrators and pumps account for.
Photo: Natural Gas STAR
The Climate and Clean Air Coalition has reported that if action is taken to reduce these short-lived pollutants aggressively, it is likely that we could cut methane emissions by 25%, and eliminate high-global warming threats altogether over the next 25 years. Van Air Systems’ PLD Deliquescent Dryer is a solution that completely eliminates emissions, making companies like Company A able to increase their pressure to the full 700 psig and increase their flow rate to over 25 MMSCFD. Van Air Systems allows NG producers to lower emissions while producing more gas and increasing profitable production.
Van Air Systems offers deliquescent dryers and desiccants suitable for natural gas dehydration while completely eliminating emissions. Whether the application requires meeting pipeline moisture specifications, inhibiting hydrate formation, preventing condensation in pipelines, or improving the combustion quality of fuel gas, we have a gas dryer to meet your application needs while still exceeding the EPA’s guidelines. Our natural gas dehydration experts at Van Gas Technologies have decades of experience and have encountered virtually every application imaginable. Specifically, Van Air Systems designed the PLD Natural Gas Deliquescent Dryer to be an economical and effective solution for natural gas dehydration that requires absolutely no power to generate. The chart below discusses the environmental and cost differences for having a glycol dehydrator or PLD desiccant dehydrator installed and maintained:
|Type of Cost & Savings||Natural Gas Desiccant Dryer ($/yr.)||Glycol System ($/yr.)|
|Annual Operating & Maintenance Costs||$4,650||$4,886|
|Gas Vented/Lost||10Mcf/year||69 Mcf/year|
|Emission Factor (Mcf natural gas bleed/ pneumatic devices per year)||0Mcf/device/yea||126 Mcf/device/year|
The natural gas dehydration experts at Van Gas Technologies have decades of experience, and have encountered virtually every application imaginable. Natural gas producers and transporters often rely on wellhead gas to fuel production equipment in remote locations where access to the electric grid is impractical or unavailable. Impurities in untreated natural gas can damage costly equipment.
The best part about Van Air System’s PLD Deliquescent Dryers is that they are easy to operate and require no electricity. You simply open the top closure every 4-6 weeks and add more desiccant. As the PLD absorbs all the moisture in the natural gas line, the deliquescent desiccants tablets will slowly dissolve into a liquid brine solution. Maintenance is as easy as draining daily and refilling monthly. However, to make things even easier, Van Air Systems manufacture automatic drain valves.
Contact Van Air Systems and make sure all your natural gas dehydration needs are met as well as the EPA’s requirements.