The Art and Science of Film Temperature to Achieve Goldilocks Efficiency

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Understanding film temperature is pivotal when delving into the intricacies of heat transfer, particularly in situations where fluids are involved. This blog post aims to unravel the importance of film temperature in various heat transfer processes. Join us as we delve into the essence of film temperature—what it is, why it holds significance, and the art of mastering its control to optimize heat transfer efficiency. Learn about its role in industrial equipment, such as hot oil heaters, tank heating coils, and heat exchangers. Uncover practical strategies for fine-tuning film temperature, ensuring your processes consistently operate within the Goldilocks zone of efficiency.

Decoding the Delicate Balance of Sizing Shell and Tube Heat Exchangers

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When it comes to optimizing shell and tube heat exchangers, a multitude of factors comes into play. These elements wield significant influence over not just the size of the exchanger but also its performance, efficiency, and overall cost. Think of it as a delicate equilibrium, where variables such as heat transfer rates, fluid flow velocities, and material properties converge to shape the final product. Enerquip specializes in unraveling this intricate puzzle, utilizing advanced calculations and simulations to engineer solutions tailored to your precise requirements. In this blog, we’ll dive into the core components that dictate the sizing of shell and tube heat exchangers, shedding light on the meticulous craftsmanship that transforms complexity into streamlined functionality. Join us in uncovering the mechanics of optimized heat transfer, where Enerquip takes the reins and innovation takes center stage. Variables That Impact the Size of a Heat Exchanger Various factors can influence the sizing of a shell and tube heat exchanger. These factors can affect the heat exchanger’s overall performance, efficiency, and cost. Thermal Attributes Affecting Heat Exchanger Sizing Here are some of the key thermal and environmental variables that can impact the sizing of a shell and tube heat exchanger: Fluid flow rates: The flow rates of both the hot and cold fluids significantly affect the sizing. Higher flow rates may necessitate larger heat exchangers to maintain heat transfer efficiency while minimizing pressure drop. Desired temperature change: The desired temperature change of the process fluid (combined with its flow rate) determines the total heat transfer (BTUs/hour) required in the unit. A smaller temperature change, or an option to recirculate the process fluid until it reaches the desired temperature, can help reduce the size of the unit. Conversely, a large temperature change will typically lead to a larger exchanger. Approach temperature: The approach temperature refers to the difference between the desired outlet temperature of one fluid and the inlet temperature of the other. A narrow approach temperature reduces heat transfer rates, requiring more surface area to achieve the desired heat transfer, typically increasing the size and cost. Conversely, a wider approach temperature improves transfer rates and typically allows for a smaller heat exchanger size. Thermal fluid properties: The thermal properties of both fluids have a significant impact on heat exchanger sizing. First, the specific heat capacity indicates the amount of heat energy a fluid can carry, with higher heat capacities typically allowing for a more compact design. Thermal conductivity is a measure of the ability of a fluid to give (or receive) heat, with higher conductivity values typically reducing the unit’s required surface area (and size). Fluid density influences mass flow rates, which in turn impacts the sizing. Fluid viscosity is a measurement of a fluid’s resistance to flow. Fluids with high viscosity will tend towards laminar flow and lead to higher pressure drops, which may require a larger exchanger to compensate. Design specifications: Design specifications like operating pressure and temperature can significantly influence the sizing of a heat exchanger. Higher operating pressures may require thicker materials which can negatively affect heat transfer (heavier wall tubes, for example). Elevated temperatures can also affect thickness and material selection in some cases, leading to a larger exchanger. Pressure drop considerations: Pressure drop refers to the decrease in fluid pressure as it flows through the shell or tubes due to friction or changes in direction. It’s a crucial factor in fluid dynamics and engineering systems. In heat exchangers, pressure drop affects the efficiency of heat transfer and can impact the system’s overall performance. Higher pressure drop can result in increased energy consumption to maintain fluid flow and temperature differentials, often requiring larger equipment or adjustments to maintain desired operational conditions. Higher pressure drop demands increased flow area, leading to larger tubes or possibly a larger diameter to maintain efficient heat transfer. Overall heat transfer coefficient: The overall heat transfer coefficient is a combined parameter that considers the effectiveness of heat transfer on both the shell and tube sides of the exchanger. All the items above combine to impact this coefficient. Maximizing this value is key to designing an efficient heat exchanger. Physical Attributes Affecting Heat Exchanger Sizing Here are some of the key physical variables that can impact the sizing of a shell and tube heat exchanger: Flow arrangement: The selection of counterflow, parallel flow, or crossflow arrangements will affect the heat exchanger’s size. In a parallel flow arrangement, both the hot and cold fluids flow in the same direction, resulting in a smaller temperature difference between the fluids along the length of the exchanger. This leads to a more uniform heat transfer, but negatively affects efficiency. In a counterflow arrangement, the fluids flow in opposite directions, creating a larger temperature difference, which improves overall efficiency and can reduce size. This is especially effective for applications with close temperature approaches. In a crossflow design, the fluids flow perpendicular to each other. This design allows for higher flows on the utility (shell) side, maximizing utilization of the available surface area. It is typically used in vapor applications, especially air heating/cooling. The choice of flow arrangement depends on the specific application and desired trade-offs between size and efficiency. Fouling and scaling: The tendency of the fluids to deposit fouling or scale on the heat exchanger surfaces over time will impact its sizing. If fouling is expected, a larger heat exchanger may be required to compensate for reduced heat transfer efficiency as the unit fouls over time. Material properties: The thermal conductivity and mechanical properties of the heat exchanger materials influence its size and design. For example, highly conductive materials allow for a more compact design due to enhanced heat transfer efficiency. Conversely, materials with low conductivity require additional surface area for effective heat exchange, increasing the overall size of the heat exchanger. Tube Design: The choice between a straight tube and a U-tube design in a shell and tube heat exchanger impacts size and performance. Straight tube designs tend to be longer and are ideal for applications with

What are Suction Heaters?

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Suction heaters are a type of industrial heat exchanger used in a variety of industrial contexts to heat viscous fluids, including asphalt and fuel oil, to a temperature at which they can be pumped. Keeping entire tanks of these types of liquids at pumping temperatures can be prohibitively expensive. Suction heaters heat only the liquid being pumped through them instead of heating an entire storage tank of products. As a result, suction heaters are an economical, cost-effective option for plants and facilities in a variety of industries.

The Role of Tank Coils in Efficient Tank Heating & Cooling

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From asphalt terminals to biofuel plants to food processing facilities, many industries rely on storage tanks to hold temperature-sensitive materials. Whether it’s keeping asphalt pumpable, blending biofuels at precise temperatures, or preventing crystallization in chemicals, maintaining proper heat is critical. In the past, some plants relied on direct-fire burners inside tanks to heat flammable materials—a risky practice. Today, tank coils provide a safer, more efficient solution by keeping the heat transfer separate from the stored product. Tank coils quietly work inside tanks to heat, cool, or regulate stored materials—ensuring consistent quality, safety, and efficiency. But how they’re designed, maintained, and applied makes all the difference. How Tank Coils Work Tank coils sit inside the tank, typically arranged in “banks” across the bottom for even heat distribution. They’re commonly fabricated from carbon steel or stainless steel for durability. Hot oil, steam, or another heating medium circulates through the coils from an external source (such as a hot oil heater or steam generator) in a continuous loop. This controlled flow transfers heat to—or removes it from—the tank’s contents, maintaining a stable temperature. Finned vs. Bare Pipe Coils: Which is Right for You? Choosing between finned and bare coils comes down to efficiency, viscosity, and tank size: Bare Pipe Coils – A simple pipe or tube, ideal for small tanks, viscous materials, or sanitary applications. They’re more cost-effective in setups that don’t require large heat transfer surfaces. Finned Coils – These coils have thin fins welded to the pipe (either helically or longitudinally) to dramatically increase surface area—up to 12 times the heat transfer of bare pipe. For large tanks or higher heat loads, finned coils offer unmatched efficiency. Helically wound fins are optimal for horizontal installation. Longitudinal fins work best in vertical setups. Hot Oil vs. Steam: Choosing the Heat Source The heating media moving through the coils can also impact performance: Hot oil coils are designed to transfer heat to the contents of a tank using hot oil as the heating media. The hot oil flows through the coils in a continuous loop, flowing in a serpentine fashion through the banks of coils. An industrial hot oil heater heats the oil as it passes through the coils. The hot oil then transfers the thermal energy to the stored material and circulates back through the system. Steam coils transfer heat using steam as the heating media. Steam from a steam generator makes its way through a header in the tank coil. Steam enters the coil and flows through the bends until it returns to the header and condenses into water. As the steam passes through the pipes, it transfers heat to the stored material in the tank. Materials of Construction Material selection depends on your process and environment: Carbon steel is an iron alloy that contains a small amount of carbon and very little chromium. It’s strong, durable, and often harder than stainless steel. However, it’s more prone to rust when exposed to moisture or corrosive environments, so it usually requires protective coatings. It’s commonly used in industrial equipment and refining applications where corrosion resistance isn’t a major concern. Stainless steel is also an iron alloy but contains at least 10.5% chromium, often with nickel and other elements. This composition gives it excellent corrosion resistance, as the chromium forms a protective oxide layer on the surface. Stainless steel is ideal for sanitary or corrosive environments like food processing, pharmaceuticals, and chemical plants. Custom Tank Coils for Your Operation At Enerquip, we design and fabricate custom steam and hot oil coils to meet the demands of your industry. Our solutions are engineered for performance, reliability, and safety—helping you protect your products, reduce downtime, and improve energy efficiency. Contact us to discuss your application or request a quote for Enerquip’s high-quality tank coils.   More from the Enerquip Blog Choosing the Right Industrial Heating Equipment Supplier Behind the Burn: How Heat Transfer Systems Refine Aviation Fuel How to Store Your Process Equipment Before Installation Thermal Fluid Heaters from Enerquip [Videos] Industrial Tank Heating Coil FAQs How Industrial Heating Equipment Works Through Asphalt Plant Operations [Video] Steam Generator FAQs

How Economizers Enhance Thermal Oxidizers

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Thermal oxidizers and economizers are game-changers in the industrial world, offering a cost-effective solution to increase efficiency, reduce energy costs, and reduce emissions entering our atmosphere. But what exactly are they, and how do they work? Let’s break it down. What is a Thermal Oxidizer? A thermal oxidizer is an industrial process unit used to treat waste gases generated from various industrial processes. It is designed to remove volatile organic compounds (VOCs) and hazardous air pollutants (HAPs) from process gases before they are released into the atmosphere. The thermal oxidizer works by heating the contaminated gases to a high temperature, typically in the range of 800-2000°F. The heat causes the VOCs and HAPs to break down into CO2 and water vapor, which are then safely released into the atmosphere. The process of breaking down the contaminants is known as thermal oxidation. Thermal oxidizers are widely used in the chemical, petrochemical, pharmaceutical, and automotive industries, among others, to meet environmental regulations and minimize their impact on the environment.

Five Ways to Increase Terminal Efficiency

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Efficiency is always a priority for any process, plant, or organization. Creating maximum output while reducing overhead is a core business practice. With so many moving parts in tank terminal operations, there are many places revenue can fall through the cracks. Make sure your operation is sealed tight with these high-impact ways to increase efficiency. Here are 5 ways to increase your terminal’s efficiency.  1. Replace boilers with thermal fluid heaters. Thermal fluid heaters and boilers are essential to the day-to-day operations of facilities in the asphalt, refining, and tank terminal industries. Organizations in these, and other industries, rely heavily on these systems to keep their product warm and pliable for pumping. While in the past, many plants have chosen steam boilers for their operations, thermal oil heating systems outperform them in a number of ways. First, the equipment and operational costs of a thermal fluid system are significantly lower than that of a boiler operation. Unlike steam boilers, thermal fluid heaters typically don’t require a full-time boiler operator. This can save upwards of $80,000 a year. Also with a thermal fluid heater, there is no need for a pretreating skid ($40,000), or deaerator ($10,000), or chemical injection system ($15,000). Next, thermal fluid is a more efficient and lower maintenance option for heating. Though water is often considered a free resource, there’s much more to it. With a steam boiler, the water pumped through the system will need continuous and expensive water treatment, a condensate collection system, and maintenance of steam traps. Don’t forget that water is highly corrosive, so if the water chemistry is slightly off, the system can corrode quickly. Additionally, water can freeze, so boiler systems require heated buildings (adding costs). If a boiler goes down and ice forms, an entire system can easily be destroyed. A thermal fluid system (hot oil) eliminates all these headaches and high maintenance costs. There are no steam traps, condensation systems, chemical treatment systems, or blow-down requirements to deal with. Most importantly, oil is not corrosive like water and will not freeze in cold temperatures. It is simply the best way to heat equipment. Thermal fluid heaters are significantly more consistent and efficient than their alternative heating system counterparts like steam boilers. In addition to decreased operational and energy costs, they are also more environmentally friendly, especially when using a low NOx burner. While many traditional plant operations use a helical coil thermal fluid heater, operators can increase their efficiency even more with superior serpentine coil thermal fluid heaters. The coil is built serpentine, creating more space between the coils to allow for even heat distribution. With an integrated convection economizer, at 86% efficiency, serpentine coil thermal fluid heaters are some of the most highly efficient heaters on the market. 2. Replace tank fire tubes with bottom-mounted tank coils. In older facilities, you’ll sometimes find dated and unsafe direct-fired heaters blasting directly into a tank sidewall. One small leak and you’ve got a major safety situation on your hands. In addition, the single flame creates hot spots and cold spots, reducing efficiency. Replacing fire tubes with tank coils also eliminates an emissions source, reducing your carbon footprint. A much safer and more economical option are tank heating coils mounted to the bottom of a tank. These coils can either be heated with hot oil or steam and can be bare or finned pipes. In most cases, finned is the most efficient way to go as the fins create twelve times the surface area of their bare pipe counterpart. Unlike longitudinal finned pipes whose fins are mounted horizontally, helically wound or vertical fins reduce the risk of coking as any sediments can fall through the fins. 3. Repair or replace old equipment and technology.  Let’s face it, all equipment has a shelf life. No matter the quality, eventually, it will need to be replaced. When heating equipment begins to break down, operations may experience problems like process fluid degradation, tube failures, high stack temperatures, high fuel costs, high maintenance costs, and inability to reach optimal fluid temperatures. By replacing old equipment, often you can quickly pay for the equipment itself with the money saved on fuel, water, and other resources.  4. Go low NOx on your burners.  Over the last decade, low NOx has become more of a mainstream practice. NOx is an abbreviation used to describe Nitrogen Oxides, a family of greenhouse gases. When fuel is burned at high heat, nitrogen oxide gases are emitted. While some operations choose low NOx for their sustainability consciousness, many states and countries now require it. Enerquip’s hot oil heaters can be built with low NOx burners utilizing flue gas recirculation or mesh head burners that can reduce NOx levels to less than 9PPM in total NOx. 5. Invest in tank insulation.  Especially in colder climates, it can be challenging to maintain the temperature of contents stored in tanks and running through pipes. Often, insulation is an afterthought, but it’s an important piece of this efficiency puzzle. Without proper insulation, valuable heat energy is lost, and it can take much more fuel to heat up the same contents to the desired temperature. The proper insulation and surface protection will not only protect the thermal properties of the product in the tank, but it will help increase its lifespan. A properly insulated tank will ensure the product inside won’t freeze due to outside temperature or deteriorate due to heat caused by solar radiation. High-Efficiency Industrial Heating Equipment from Enerquip Enerquip (and the former American Heating Company) has been manufacturing quality heating equipment for decades. With robust building standards, much of our equipment is still working hard decades later. With continuous process improvement at our core, our equipment has grown with us. Ready to start talking about strategic equipment planning? Bring us in on the conversation. Contact us or request a quote today. More from the Enerquip Blog Thermal Fluid Heaters from Enerquip [Videos] Industrial Tank Heating Coil FAQs How Industrial Heating Equipment Works Through Asphalt

Helical Coil Thermal Fluid Heaters from Enerquip [Video]

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Enerquip Helical Coil Heater Skid The Enerquip helical coil skid is a complete system, which includes a high-efficiency burner, recirculating pump, control panel, safety alarms, burner shell, range fly, and exhaust stack. Low NOx burners are also available for required applications. With some simple wiring and attachment of the gas supply, it’s ready for production. Made in the USA Made right here in the USA, our ASME code stamped systems are fabricated by our team of ASME code welders. Our high-quality heaters are made to run for 20-30 years, and even longer.

A New Landscape for Biofuels Blending

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With every year of increasing fuel demand, attention is cast forward to assess the current landscape of the biofuels industry. Certainly 2022 has been no different, bringing with it a lowering supply of available petroleum products and a subsequent rise in both demand and price. This has resulted in the metaphorical tightening of metaphorical belt loops on a national scale. As we move forward into the latter half of 2022, what does this mean for the overall impact on the biofuels industry and how can biofuels blenders best capitalize on the global uncertainty? Keep reading. Political Climate Predicts Greater Biofuel Demand Experts have expected to see an increasing demand in petroleum and fuel products this year, with the resurgence of many industries set back or in lower production processes due to COVID-19. However, national demand for biofuels has outpaced expectations due to unforeseen geopolitical developments from the last few months. The United States’ ban on Russian-sourced oil on March 8th has been felt across the nation, with significant price increases at the gas station and friction in fuel-heavy industries. These factors have led to national interest in the increased production of biofuel. Since the ban was enacted, there have been increasing pressures to step up the production of both ethanol and biodiesel as a means to lower the price point Americans are seeing at every pump. This request has come from local farmers, whose supply of corn would be used to blend into billions of gallons of corn-based ethanol, soy-based diesel, and various other biofuels. This process has already seen a positive impact on the revenue of farmers and lesser dependency on energy imports since the Renewable Fuel Standard was introduced nearly 17 years ago, mandating a certain percentage of America’s fuel production to incorporate renewable blending. While there are alternatives to a greater biofuel blending initiative in the later half of 2022, the consensus seems to be that none of them will be long-lasting options. For instance, a suspension of the federal gas tax would take valuable funds out of the nation’s infrastructure. A shift towards a higher emphasis in biofuel production would not only solve problems with the ban and price hikes of petroleum. Ultimately, signs point to an increase in US-based biofuels blending processes being the next logical step for national autonomy. Biofuels also further greener initiatives while lessening the harm usual mining places on the earth and atmosphere. The Role of Heat Exchangers in Biofuels Blending With an increasing focus in biofuels production, key players in the biofuels industry are solidifying next steps for the anticipated increase in demand. While guaranteeing the supply chain and external elements will be crucial for the production of this resource, technology must be monitored to ensure it is up to industry standards to facilitate biofuels blending. In fact, heat exchangers play a crucial role in the manufacturing of biofuels. Here’s how. Traditionally, a heat exchanger’s primary use in biofuels blending is through the condensation of pure or mixed methanol for recovery and purification after the esterification and transesterification processes have been completed. This process is integral to biofuel’s renewable nature. When heat exchangers are designed for the process of biofuels blending, they are crafted carefully to meet rigorous thermal tolerances. Only under precise specifications and functionality requirements can biofuels be crafted. Next Steps for Biofuels Blenders With new biofuels processes and mandates comes a greater demand for intricate and trustworthy biofuel heating equipment. Generic heat exchangers and other technologies used for biofuels blending may be outdated or inappropriate for anticipated capacity or regulation. It is highly recommended that biofuels blenders perform a thorough assessment of their facilities in light of the increasing demand for nationally-sourced biofuel. If you have any outdated parts or technologies, consider a repair or even a replacement. If you use thermal fluid heaters in the production of biofuel, consider learning about how serpentine coil technology can set your technology apart from the competition to capitalize on the increased demand. Enerquip manufactures expert heat exchangers and thermal fluid heaters for many applications, including the renewable fuel industry. If you have a question or would like to discuss making changes to your facility, contact Enerquip to get started. More from the Enerquip Blog How Tank Heating Coils Work How Economizers Enhance Thermal Oxidizers Five Ways to Increase Terminal Efficiency Industrial Heat Exchanger FAQs