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Thermic Fluid Heater is most popular in almost every industries and it is being used for various heating applications due to unique advantage over other heating systems like steam heating, electrical heating, direct firing, air heating etc., because of the following exceptional advantages:-

  1. Very low working pressure and safe from explosion hazards.
  2. Heat transfer medium or working fluid remains in liquid phase throughout and higher overall heat transfer.
  3. Greater efficiency of heat utilization, superior fuel-saving possibility, and better return on investment for the industry.
  4. No botheration continuous water treatment for feed water in case of steam boiler.
  5. No problem of scale deposition on heating surface.
  6. New generation thermic fluids with excellent properties are available in the market
  7. Better heat transfer coefficient, higher thermal stability, and long-life cycle
  8. Exemption from Indian Boiler Regulations Act and related formalities

Thus, many unique advantages when selecting the thermic fluid heater for your heating applications over steam heaters due to its specific characteristics. Considering the physical and chemical properties of thermic fluids, it is so easy to handle and operate as per the requirements of industries. On the contrary, the physical properties of the water are not very attractive to carry-out easy operation of heating systems in the factories or industries even though the chemical properties of the water is incredibly safe and inert. Though the thermic fluid has many undesirable chemical properties, but physically, the behavior is very acceptable.

When we heat any fluid, it is essential to have energy input to heat-up and change the phase and in this initial process,  water tends to be a dangerous but afterwards it is always changed enough to manage the process and heating. In turn, thermic fluid is always satisfactorily performing in its operating range and may deteriorate into uncontainable situation if do not take due care and precautions during filling, operating and topping-up in operating conditions. Though, thermic fluid system can ensure reliability of performance, economic operations of thermic fluid heater, the safe operating and protection from fire hazards can only be accomplished through the understanding and knowledge on the resulting issues as follows:

  1.  Right selection of thermic fluid from the many fluids available in the market
  2. Understanding of basic physical and chemical properties
  3. Selection of fluid is a critical factor to ensuring reliability, performance, and long life

Nirmal Energy Limited, Ahmedabad and its associated Companies serving in this field for 22 years and more than 3000 thousand customers taking advantages of their services. They are advising and serving the industries on the appropriateness of thermic fluid for their heaters and guiding them on selection of suitable design and features of Thermic fluid heaters in the backdrop of mushrooming of copy-cat manufacturers of Thermic fluid heaters without understanding of basic design features of Thermic fluid heaters and system.

Basic design features of thermic fluid heaters are necessary to be built-in to ensure not only the best possible performance of heater but also ensuring the longest possible life for the thermic fluid. Thermic fluid is by-products of petroleum or petrochemical processes, in turn, thermic fluid heaters are to be suitably designed by competent engineers. Therefore, it is so critical to have design competency to design the heaters with latest norms and design codes and also to suit the inherent properties of the thermic fluid and undoubtedly the design of thermic fluid heaters cannot be performed by any fabrication companies or any ordinary design. We, at Nirmal Energy Limited, people having over three decades rich experience in heater industry and thoroughly understanding the nature of thermic fluid, available in India has been continuously propagating all the necessary design features in thermic fluid heaters, deaeration systems and best practices in thermic fluid design.

With respect to the heater and thermic fluid service temperatures, bulk temperature, film temperature, economic operating temperature of fluid and life cycle cost etc are significant to understand. We have also observed that even though the out let temperature of the heater  may indicate the bulk temperature well below 300°C, the actual temperature of vapor film be far above 300°C which is sufficient to crack the fluid to high boilers, low boilers and lighter hydrocarbon gases and decrease the flash point, to dangerous value, especially in the case of mineral oils.

The thermally cracked gases would be formed at tube walls, gradually make a way for fouling, accumulate as a tiny particles of carbon compound sticking inner side of the coil and create hot spots and can lead to various consequent failures and even leading to fire.

In a larger extent, the root cause of thermic fluid deterioration attributed to the design of thermic fluid heater or failure to maintain thermic fluid service temperature within the allowable temperature limits, these are some of the factors.

There are many misguided notions about the Thermic fluids heaters, Thermic Fluids, its effective use, permissible operational parameters and its working temperatures etc., due to lack of expertise and know-how about latest technical developments in the field of Thermic fluid heaters and new generation thermic fluids.


(Author is presently working as a Principal Consultant – Nirmal Encon Services, Director Technical - Heatran Engineers Pvt Ltd, and Group Executive Chairman & MD- Nirmal Energy Limited & Its Associated Companies, Ahmedabad and having more than three decades of experience in the similar fields.) 


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