A plant inlet filter is a pressure vessel with an opening enclosure at one end to remove the filter elements. It is located at the origin of a natural gas processing plant and is designed to remove solids from the inlet gas stream. In the extensive gas facilities, it is often positioned downstream of the inlet separator, after the liquids separate from the inlet gas stream. However, in smaller gas plants, the inlet filter may also act as the inlet separator, taking on a dual-purpose role. Often, pressure vessel fabricators and designers add a collection vessel underneath horizontal filters to collect any free liquids.
What is the Purpose of the Inlet Filter?
Typically, many impurities, including rock particles, sandstone, clay, silt, and more, are present along with natural gas during its production. In addition to this, the gas also picks up other particles such as corrosion contaminants from the pipelines. It is essential to remove these contaminants before processing the natural gas in a glycol dehydration unit or amine sweetening system. An inlet filter helps to make this task easy and hassle-free.
Importance of Inlet Filter
When the impurities enter liquid-based processes such as amine sweetening systems and glycol dehydration units, they contaminate the liquid chemicals. This reduces the effectiveness of the process, resulting in an upset condition. The contaminants degrade the performance of the system or stop it from working entirely. As a result, the gas may become off-spec and unfit for usage or sale. In addition to this, it may increase the overall operating costs. Having an inlet filter can help you avoid such difficulties. It helps to regularly change the filters because it is more cost-effective than regenerating glycol and amine solutions.
Essential Aspects of Inlet Filter Design & Fabrication
When designing pressure vessels such as the inlet filter packages, it helps to avoid the following mistakes:
- Not Using High-Quality Isolation Valves
A top-quality valve, preferably double block and bleed valve, is essential to ensure safety when changing filters. This is because the plant inlet is directly connected to this piece of equipment when the operator changes the filters.
- Absence of Catch Pan or Platform
Changing the filters involves dealing with solids, fluids, and sludge. It helps to ensure that the catch pan is big enough to catch any fluids that may drain from the filter housing closure and hold at least one change of filter elements. Also, incorporate a screen or grating at the bottom of the pan to allow the filter elements to drain. If the canister opening is high from the ground, install a working platform instead of using makeshift stands or ladders to ensure safety when working on the equipment.
- Using Small Drain Lines and Valves
We often find filter canister drain lines too small in diameter and prone to plugging off. Make sure that the drain lines have a diameter of at least 1 ½ inch and use full port valves. This is because the plant inlet filter collects solids and liquids, which turn into sludge when mixed. Also, ensure there is enough space between the outlet of the drain valve and the skid floor to connect a house without using an elbow.
- Primary Instrument Isolation Valves are Missing
The first valve used to isolate instruments such as pressure gauges and transmitters should be a high-quality gate or ball valve. It also helps to install a secondary valve between the primary valve and the instrument. This way, if the secondary valve fails to close, the primary valve acts as a back-up.
Pressure Vessels Fabricated as per the ABSA Standards
Aspire Energy Resources Inc. is known for providing refurbishing and packaging services for plant inlet filters. With over 20 years of experience in the industry, we have created a unique identity when it comes to oil and gas equipment. We are experienced pressure vessel fabricators, providing economical solutions that meet or exceed the required ABSA standards. We also look for every opportunity to improve the ease of operation and maintenance of every inlet filter package we build.
For more information about our refurbishing services, reach out to our experts by calling toll-free at 1-800-993-9958.