Natural gas processing can be a complicated business. There are pipelines, compressors, separators, fractionation systems, cryogenic equipment, refrigeration systems—and a lot of heat moving around between them.
In many of these applications, controlling temperature isn't just about keeping a process running efficiently. It can be critical to separating gases, recovering valuable products, reaching cryogenic temperatures, and getting natural gas into a form that can be transported economically.
That's where plate-fin heat exchangers come into the picture.
These compact heat exchangers are particularly well suited to gas-processing applications because they can provide a large amount of heat-transfer surface in a relatively small footprint. They're also capable of handling multiple streams and very low temperatures, making them an important piece of equipment in natural gas and LNG facilities.
But before getting into how they're used, let's answer the question we hear first:
What Does LNG Stand For?
LNG stands for Liquefied Natural Gas.
Natural gas is primarily methane. When natural gas is cooled to approximately -260°F (-162°C) at atmospheric pressure, it changes from a gas into a liquid.
Why go through all that trouble?
Because liquefying natural gas dramatically reduces its volume, making it much easier to store and transport. LNG can be loaded onto specialized ships and transported long distances to markets that aren't connected by pipeline.
And getting natural gas from its original gaseous state to LNG requires some serious heat transfer.
Where Plate-Fin Heat Exchangers Come In
Think of a plate-fin heat exchanger as a highly compact way to move heat between process streams.
Inside the exchanger, layers of plates and corrugated fins create numerous flow passages. Depending on the design, several different streams can pass through the exchanger and exchange heat without mixing.
This is especially useful in natural gas processing because one stream may need to be cooled while another stream needs to be warmed. Instead of adding a separate exchanger for every individual duty, a carefully designed plate-fin exchanger can sometimes integrate several heat-transfer duties into a single compact unit.
That combination of high surface area, compact construction, close temperature approaches, and multi-stream capability makes plate-fin technology particularly valuable in gas processing and cryogenic applications.
Now let's look at where these exchangers actually fit into the process.
Image from Genemco
Link to Plate-Fin Heat Exchangers
Natural Gas Processing: Getting the Gas Ready for Its Next Step
Natural gas doesn't necessarily arrive at a processing facility in the form that customers ultimately want.
Depending on where it comes from, the incoming gas can contain water, heavier hydrocarbons, carbon dioxide, nitrogen, and other components that need to be removed or separated.
Temperature control is an important part of that process.
Plate-fin heat exchangers can be used to cool or heat natural gas streams and recover heat between process streams. In cryogenic gas-processing facilities, they can be incorporated into systems designed to bring gas down to the temperatures required for separation.
One of the biggest advantages is that heat doesn't necessarily have to be thrown away.
A hot process stream may have energy that can be transferred to another stream that needs to be warmed. A cold stream leaving one part of the process may be used to precool another incoming stream.
In other words, the process can essentially recycle its own thermal energy.
That can improve overall efficiency and reduce the amount of external heating or refrigeration required.
LNG Liquefaction: Turning Gas Into a Transportable Liquid
LNG liquefaction is one of the applications where plate-fin heat exchangers really get to show what they can do.
Before natural gas can become LNG, it must be cooled to cryogenic temperatures—approximately -260°F (-162°C).
That's a tremendous amount of heat that has to be removed.
A liquefaction plant uses a series of refrigeration and heat-exchange steps to progressively cool the natural gas. Plate-fin heat exchangers can serve as part of these cryogenic systems, transferring heat between process and refrigerant streams.
Their compact construction and ability to handle multiple streams make them particularly useful when engineers are trying to get a lot of thermal performance into a relatively small piece of equipment.
And at an LNG facility, "small" can be a pretty meaningful word.
These are enormous industrial operations. Every square foot of space, every pound of equipment, and every bit of energy efficiency can matter.
NGL Recovery: Separating Valuable Liquids From Natural Gas
NGL stands for Natural Gas Liquids.
NGLs include hydrocarbons such as ethane, propane, butanes, and natural gasoline.
These components can have significant commercial value, so recovering them from the natural gas stream is an important part of many processing operations.
Plate-fin heat exchangers can be incorporated into NGL recovery systems to provide the controlled cooling and heat recovery needed to help separate heavier hydrocarbons from the natural gas stream.
In cryogenic recovery processes, the gas may be cooled to very low temperatures to condense or separate certain components.
Once again, the heat exchanger isn't doing the separation by itself. Instead, it's an important part of the thermal system that makes the separation process possible.
And because the same exchanger can potentially handle multiple process streams, engineers can design highly integrated systems that recover and reuse energy throughout the process.
Nitrogen Rejection: Removing Nitrogen From Natural Gas
Not every natural gas stream has the composition required for pipeline specifications or LNG production.
Sometimes nitrogen needs to be removed.
That's where a Nitrogen Rejection Unit (NRU) comes in.
Cryogenic nitrogen rejection processes take advantage of the different boiling points and phase-change characteristics of nitrogen and methane. This requires very low temperatures and carefully controlled heat transfer.
Plate-fin heat exchangers are well suited to these applications because they can handle cryogenic temperatures while providing efficient heat transfer between multiple streams.
For example, a cold process stream can be used to precool another stream entering the system, recovering energy that might otherwise be lost.
In a process where temperatures are extremely low and energy efficiency is important, that kind of heat integration can make a significant difference.
Gas Cooling: Getting the Temperature Where It Needs to Be
Sometimes the job is simply—and critically—to cool a gas stream.
Gas cooling can be required at numerous points throughout natural gas processing and industrial gas systems.
Plate-fin heat exchangers can provide cooling by transferring heat from the process gas to another, colder fluid or process stream.
Because plate-fin exchangers can be designed with a high surface-area-to-volume ratio, they can provide substantial heat-transfer capacity without requiring an enormous equipment footprint.
This can be particularly valuable in facilities where equipment needs to fit into a tightly engineered process area.
And anyone who's ever worked around an industrial facility knows that "we'll just find somewhere to put it" isn't always a realistic engineering strategy.
Gas-to-Gas Heat Recovery: Don't Throw Away Good Heat
One of the most interesting applications for plate-fin heat exchangers is gas-to-gas heat recovery.
Instead of using a separate heating or cooling source, two gas streams can exchange heat with one another.
Imagine one gas stream leaving a process that is warmer than the incoming gas stream. Rather than simply sending that heat away, a plate-fin heat exchanger can transfer some of that energy to the incoming stream.
The result is a more integrated process.
This approach can help:
- Recover otherwise wasted thermal energy
- Reduce utility consumption
- Preheat or precool incoming process streams
- Improve overall process efficiency
- Reduce the load on separate heating or refrigeration equipment
For large-scale gas processing, small improvements in thermal efficiency can become meaningful when the process operates continuously.
Why Plate-Fin Heat Exchangers Make Sense for Gas Processing
So what makes plate-fin heat exchangers such a good match for natural gas and LNG applications?
It comes down to several characteristics working together.
Compact Design
Plate-fin construction packs a large amount of heat-transfer surface into a relatively small volume.
High Heat-Transfer Area
The fins dramatically increase the available surface area for heat transfer.
Multi-Stream Capability
Certain designs can allow several streams to exchange heat within the same core, making them useful for complex process integration.
Cryogenic Capability
Brazed aluminum plate-fin heat exchangers are particularly well suited to very low-temperature applications.
Heat Integration
They can be used to transfer heat between process streams, helping facilities make better use of energy already present in the system.
For natural gas and LNG facilities, those characteristics can make plate-fin technology an important part of the overall thermal design.
What Happens When the New Heat Exchanger Is Months Away?
Here's where things get a little more practical.
Engineers can design the perfect system. OEMs can build the perfect piece of equipment. Operators can approve the project.
But sometimes the equipment has a long lead time.
And production doesn't necessarily care.
If an existing heat exchanger fails or a customer needs additional capacity while waiting for a new unit, there's often a gap between "we need it" and "the new equipment is ready."
That's one of the situations where Genemco can help.
Genemco specializes in pre-owned industrial refrigeration and food processing equipment, giving customers another option when waiting isn't practical.
A used plate-fin heat exchanger may not be the permanent solution. It doesn't have to be.
Sometimes it simply needs to keep the process moving until the long-term solution arrives.
Think of it as a bandaid for the process—or a tourniquet when the situation is more serious.
The goal is to help keep an operation running while the new equipment is being manufactured, shipped, installed, or commissioned.
Image from Genemco
Link to Plate-Fin Heat Exchangers
OEMs: Let Us Help You Be the Hero
If you're an OEM, we want to make one thing very clear:
We're not trying to take your sale.
In fact, we'd rather help you save the sale.
You've already designed the solution. You've earned the customer's trust. You've sold the new equipment.
Then the customer asks the question nobody wants to hear:
"What are we supposed to do until it gets here?"
That's where Genemco can potentially step in.
Rather than your customer shutting down production or scrambling for an emergency solution, consider using Genemco as a temporary bridge.
You continue to provide the long-term solution.
We help find equipment that can potentially keep the customer operating in the meantime.
You get to be the hero.
The customer gets a way to keep moving.
And when the new equipment finally arrives, your permanent solution can take its place.
That's a much better conversation than telling a customer, "You're going to have to wait."
Why Choose Genemco?
When you're looking for pre-owned industrial equipment, availability is only part of the equation.
You also want to know who you're buying from and whether they understand the equipment you're looking for.
Genemco has been buying and selling pre-owned industrial refrigeration and food processing equipment for decades, with a large inventory of equipment serving customers across a variety of industries.
That experience can be particularly valuable when you're looking for something specialized.
Rather than starting from scratch, Genemco can help you explore available equipment and determine whether something in our inventory may fit the application.
For an operation facing a long lead time, unexpected equipment failure, or an immediate need for additional capacity, having another source to turn to can be valuable.
Because in the natural gas and LNG industries, the process doesn't stop just because the replacement equipment is still being built.
Sometimes you need a solution for right now.
And that's where pre-owned equipment can have a place.
Keeping the Gas—and the Project—Moving
Plate-fin heat exchangers may not be the most familiar piece of equipment outside of specialized processing industries, but inside natural gas, LNG, cryogenic, and industrial gas facilities, they can play a critical role in moving heat where it needs to go.
From natural gas processing and LNG liquefaction to NGL recovery, nitrogen rejection, gas cooling, and gas-to-gas heat recovery, their compact design and high thermal performance make them a valuable tool for complex process systems.
And when the right new equipment is months away, Genemco can help bridge the gap.
The permanent solution can still be the permanent solution.
We can simply help you get there.
