Why Sometimes It’s Better To Buy New Heat Exchanger Than Keeping Old One

Things aren't made the same way they used to be" is a widespread adage that can be used to a variety of appliances, heat exchanger makers, and other products that are no longer built to the same high standard as they were 20, 30, or 40 years ago. While you can brag about your old toaster oven that constantly browns your English muffins to perfection, there are times when keeping certain pieces of equipment in use is actually counter-productive.

The truth is that the new ones have the potential to be significantly superior in a variety of ways. In addition to consuming too much energy, aging equipment has a higher rate of downtime because failures occur more frequently and require more maintenance. When looking for a new solution that can work for longer periods of time without requiring service, this lost time must be considered. In some cases, upgrading to a new unit to take advantage of the increased features offered can be the best option.

When is it a smart idea to invest money in new equipment when you already have one that works? Most plant managers who work on a tight budget look for ways to save money wherever they can and follow the mantra, "If it ain't broke, don't fix it." This isn't always the case, especially when it comes to the equipment used in the chemical process industries. When you consider all of the new developments and technology that have been discovered and implemented in the last decade, newer equipment can not only improve the performance of your process but can also improve efficiency and productivity to the point where the long-term benefits of a new unit often outweigh the capital expenditure.

Heat exchangers are a great example of this type of equipment. Corrosion, fouling, and thermal expansion are all common problems in heat exchanger functioning. These issues have an impact on the units' reliability, but their inefficiency can also contribute to the lengthening of process durations. Consider how much more efficient and profitable your process would be if you could run five batches in the time it took to run four before. This is the kind of efficiency that new, high-performance heat exchangers can provide.

Let's take a look at the key models utilized in CPI operations before we discuss what's superior about new heat exchanger designs. There are a variety of heat exchanger options available, and some forms are more suited to certain uses than others. While there are other variations, the three primary categories are as follows:

Shell-and-tube heat exchangers: Due to their adaptability, they have remained a steady cornerstone in the chemical process sector. A bundle of tubes containing fluid runs longitudinally through a shell containing a second type of fluid in the design. The shell fluid runs over the tubes, allowing heat transmission to occur.

Plate-based heat exchangers: They use plates to expose fluids to a wider surface area than other systems. Welded-plate and gasketed-plate versions are the two most popular forms of plate HEs. Their compact designs allow them to fit into tight locations, and the materials used in their production (typically stainless steel or alloy) allow them to be utilized in applications requiring high pressure and temperature tolerances.

Coil/Spiral heat exchangers: In this design, two fluids flow in opposite directions through a set of helical tubes. These units have a small design and provide great thermal efficiency in demanding applications. They also have a lower fouling tendency, making them a viable option for tough services.

There are many more types of heat exchangers than the three described above, but this provides you an idea of the three most common. So, returning to the topic at hand, why should you consider buying a new heat exchanger if your old one is still functional?

Better Construction Material

Many advancements have been made to today's construction materials. Old heat exchangers produced more than two decades ago were almost certainly made of carbon steel or copper tubes, which were the most common metals at the time. Fast forward to today's process conditions, and those MOCs are no longer enough for corrosion protection, especially when dealing with some of the corrosive compounds used in many current applications. Additionally, some older equipment that could not tolerate the corrosive environment of a certain process was designed using thickened material to compensate for the inevitable corrosion. While some may consider this a creative solution, it's more or less a hack to get some use out of equipment that would otherwise be regarded unsuitable for the task. There are alternative blends of metals and totally new metals that are engineered to handle the corrosive properties of modern chemicals, so materials don't need to be thickened for corrosion. Furthermore, the new materials are lower in weight and more dependable, resulting in increased efficiency.

Secure Designs

Another aspect to think about is safety. Newer equipment has greater safety requirements than older equipment since it is built with the latest and finest materials and designs. Some older heat exchangers, in fact, do not fulfill the environmental or safety standards that have been established in recent years.

To overcome the shortcomings of their predecessors, new advancements in heat exchanger design have also been made. Unnecessary tension on the heat exchanger can lead it to break over time in operations where thermal expansion happens at different rates. Flow-induced vibrations in shell and tube heat exchangers, for example, are a red flag in terms of safety. While expansion joints can help with these problems, newer designs, such as a floating tube sheet-style exchanger that is fixed on one end but can move within the shell on the other, offer superior options. The unit is protected from damage during thermal expansion by the spring action that has been enabled. Sealing technology has progressed as well, making units safer from cross-contamination.

Additional Unique Application Options

Some heat exchangers may not have been considered for CPI equipment in the past, but improvements in manufacturing and design have made them a viable solution for a wide range of demanding chemical process applications, including severe service processes and pharmaceutical applications that require an extra level of reliability and compliance.

The QVF coil-type heat exchanger, for example, is an example of such a machine that solves an issue for the pharmaceutical sector. The material, which is made of inert borosilicate glass 3.3, has high corrosion resistance as well as excellent process visibility. The tube coil is fused to the shell to prevent cross-contamination between the two fluids, resulting in a seal-free solution. For some applications involving difficult-to-process, highly viscous fluids, mixing is an interesting alternative. It can efficiently boost heat transfer and prevent product burning by including a mixing component within the heat exchanger.

While improving your operation's efficiency will cost you money, it's also crucial to assess how much it would cost you if you don't make those improvements. The approach to improving the performance of your process can be to replace your existing heat exchanger with a new one, which features safer designs, improved materials, and better options to maximize efficiency and uptime. With the use of new technology and customizable designs, you can have a solution tailored to your exact needs.

Alaqua is processing equipment including a heat exchanger equipment supplier worldwide based in the USA. Along with equipment, we also offer various services for processing equipment. Get a quote for your processing equipment and services today!

Features of Evaporators Used for Vegetable Cold Storage | Alaqua Inc

Different types of heat exchangers are required for various applications. Lower fins per inch (FPI) are frequently used in sectors such as pulp and paper to reduce airside fouling and make cleaning easier. Weight is a consideration in other applications, such as the military, and it influences material choices. In this piece, we'll look at some of the unusual design features frequently added when creating heat exchangers for the refrigerated storage of potatoes, onions, beets, and other vegetables. Alaqua offers processing equipment including cold storage evaporators and processing equipment services worldwide based in the US.

End-User Customization Capability

To avoid spoilage, commercial agriculture storage warehouse cooling systems frequently operate at temperatures just above freezing. Frosting on coils is a serious worry because of the low temperatures and humidification, as a result, many businesses employ electric heating components to prevent frost and ice from forming on evaporators. Knowing this, some companies such as Alaqua add heating notches in their coils to allow these devices.

If heater notches are required, customers can choose from three design possibilities. The first involves punching heater notches into the fins themselves with a special die. To accommodate the heaters, strategically positioned dead tubes in the coil can be utilized, or a split fin pack can be employed, which consists of two fin packs constructed into one casing with enough space between them to fit the heaters.

For contaminant-free meals, use clean, cleanable equipment

Prior to delivering items out to the customers, providers totally degrease them with a vaporized degreasing solution. Customers will obtain a clean, ready-to-use heat exchanger that is free of impurities in this manner.

While coils may appear to be in perfect condition at first, they will not last long in the field. Due to the presence of dirt and other particulates, agricultural storage coils must be constructed to be easily cleaned in the field. End-users will appreciate design decisions such as thicker fin gauges to withstand pressure washing and increased space between fins, which allow them to clean coils without removing them from service. Lowering the FPI helps to reduce the icing issues discussed previously.

Corrosion-resistant materials to lessen the need for replacement

Coatings are commonly used in the fertilizer sector due to the presence of a variety of chemical and environmental corrosives such as ammonia from fertilizers. E-coat, or electrocoating, is used in the industry since it's thin (about 1 mil dry film thickness) and reduces heat transfer by less than 1%. Furthermore, when combined with a hydrophobic topcoat, condensate water - which often contains chemicals - beads off of the fins, reducing contact with equipment and the risk of corrosion.

If you like this blog, please also check out our latest blog on what equipment is used for food processing. 

Fin stock that has been pre-coated with a blue corrosion-resistant lacquer, used in the condenser, is another possibility. Pre-coated fin stock, unlike the post-build coatings solely protects fins and is best suited for settings where corrosives are present in the airstream but not so much on the fluid side. Pre-coated fin stock is a cheaper alternative to the above coatings, but it is also less robust, making it unsuitable for harsh corrosive environments.

A third option is Here site P-413, a baked-on phenolic coating that protects against a wide range of acids, solvents, and inorganic salts. Because of its high cure temperature and unique chemistry, Here site P-413 is a popular choice for commercial crop storage. Heat transfer is reduced by 1% using Here site P-413, similar to an e-coat. It has a dry film thickness of roughly 1 mil, which is similar to that of the other products.

However, each application is unique, with some requiring substantially less coating expenditure and others far more. There are a number of tools available to assist in determining the optimal coating package for a certain application.

Braze joints of superior quality for long-term leak-free operation

And, it's widely assumed in the industry that a higher silver content leads to a more ductile joint, which is less vulnerable to stress and vibration. Then, before shipping, coils should be thoroughly tested with dry nitrogen to confirm that they satisfy specifications and will not leak in the field. Higher-silver-content braze rod also allows to combine of incompatible metals more easily, broadening the material combinations that can be utilized and boosting the chances of being able to manufacture exactly the part customers require. Alaqua is processing equipment such as solvent recovery, distillation, evaporator, evaporator condenser, crystallizer, heat exchanger, and spray dryer supplier worldwide. Along with supplying processing equipment, they also offer services for the processing equipment such as installation and commissioning, troubleshooting, field services, etc. Do you employ heat transfer for agricultural storage and want to discover if these coil designs can help you improve efficiency? Please contact Alaqua and get your queries answered…!