When it comes to following basic business principles, the oil and gas industry is no different from any other: reducing energy, increasing operational efficiency and cutting costs are critically important to any successful enterprise. That's what makes the trend toward modular, on-demand boilers a smart choice for oil and gas operators.

Today's modular, on-demand boilers can make a significant improvement in the operations of rail terminals used for oil transportation. Replacing the old, large, inefficient boilers from an earlier era with today's more efficient modular units can mean greater overall efficiency and cost savings that travel straight to the bottom line.

The evolution of boiler technology

How do these new systems differ from the traditional units we all know and likely still have? Let's start with a look back. From as early as the 18th Century, steam boilers have been extremely large pieces of machinery that use lump coal as fuel and achieve very inefficient pressure output. In contrast, today's more efficient units generate higher steam pressure while using fuels such as natural gas, propane, fuel oil or biogas. These newer boilers are becoming increasingly popular in a wide range of industries due to a higher efficiency output, lower energy consumption, and unique compact, space-saving designs.

Conventional boilers in the oil and gas industry

With the decline of pipeline capacity, the oil and gas industry is becoming increasingly dependent on rail transportation. According to the Association of American Railroads, over 11 billion gallons of crude oil were shipped in 2013, and crude imports from Canada by rail have increased by 1,900% since 2011. When moving this type of freight (heavy oil such as bitumen, black wax or paraffin-based oil) it takes a great deal of steam energy for liquefaction while loading and unloading the rail cars to get the product to its final destination.

Problems arise when the trains don't run on time. The journey from Canada to the Gulf Coast refineries, for example, takes several days, with the oil solidifying along the way. Delays en route can cause unpredictable arrival times, and more often than not, the destination terminal will not know the exact ETA or number of incoming rail cars until it arrives. Regardless of inconvenience and unpredictability, the terminal has to be ready to heat and unload the oil quickly at all times.

Because traditional boilers require up to 90 minutes to become fully operational, the inclination is to fire them up well before the incoming train arrives. Since arrival times are never guaranteed, terminals are forced to keep their boilers running nearly full-time in anticipation of need. This means burning through fuel, and money. This is a prime example of when modular and on-demand systems make a significant difference on the bottom line.

The advantages of modular, on-demand boilers

Modern on-demand systems can go from ice cold to red hot in just about five minutes—which significantly reduces the amount of lost fuel and energy anticipating arrivals. They are ready to go when you need them.

Just as important, these units achieve even greater efficiency due to their modular design: They can share capacity for load demand among multiple compact units. If comparatively little capacity is needed, fewer boilers can be activated. If more steam is required, you simply activate more boiler modules. Even if the terminal operator doesn't know whether an incoming train will contain 30 cars or 120 cars, not only can he control when to start them up, but can control the exact energy and capacity needed on a case-by-case basis.

In addition, when the demand for steam power rises and falls while workers are attaching and detaching the steam hoses to and from the train cars, modular, on-demand boilers can respond much more quickly and efficiently. They offer the same operational efficiency regardless of load. Low-fire or high-fire, it's all the same. In contrast, a conventional boiler has a four-to-one turndown with a severe impact on efficiency below 50% firing.

Of course, many rail terminals operate with redundancy in the event of a system failure or simply to assure the ability to unload oil quickly without paying penalties to any parties involved. With conventional boilers, redundancy represents a major investment; from the hardware itself, to space requirements and fuel costs if multiple units need to be run simultaneously.

On-demand systems also are more efficient simply by the nature of their design. While a conventional boiler will lose 240,000 Btu/hr. through its exterior, on-demand units lose just 60,000 Btu/hr. when fully operational. That's a significant difference. Imagine leaving your car running overnight to be ready for you in the morning: that should help you visualize the amount of energy wasted with traditional units.

On-demand boiler systems are managed by a master controller to help achieve further energy-efficiency. The controller uses a sensor to monitor steam demand, automatically bringing the boilers online, regulating their output, and shutting them down as they are needed. Advanced software is used to send commands to individual terminals to adjust the boilers' operation for maximum overall efficiency.

As the Federal Energy Management Program (FEMP) put it in a recent bulletin, "Modular systems are more efficient because they allow each boiler to operate at or close to full rated load most of the time, with reduced standby losses."

The compact size of on-demand systems also offers design flexibility that is simply not possible with larger systems. On-demand boilers require only about half the space of conventional boilers. They also do away with the space requirements of standard tube-pull and door-swing designs.

Boiling it down

Today's efficient modular, on-demand systems are gaining acceptance far beyond the train terminals of the oil and gas industry. They are also being used in a broad range of other industries and facilities. These include chemical and food-processing plants, laundry services, distilleries, hospitals and breweries, to name a few. Installations are significantly reducing energy costs and the bottom line as compared to operating traditional boiler systems.

Cost savings of 20% or more is common across the board. That's a key attribute to their increasing demand in a variety of industries. 

Selecting the right kind of boiler system means considering the big picture: fuel costs, space design and energy consumption. Regardless of the industry or application, the use of modular, on-demand systems is increasing for all the right reasons.

Truong Duy