You may believe that all heat exchangers are the same, but this is not the case. There are numerous varieties and models, each of which is designed for a specific function and use.
What is the purpose of heat exchangers? Of course, the necessity for thermal processing of diverse goods, whether in the food, dairy, chemical, or pharmaceutical industries, is the correct response to this issue.
In today's marketplace, a large selection of heat exchanger styles are available, and one of the first issues that arises on "standard" applications is the fact that many various types of heat exchangers can be found, all performing the same functions. Is this correct or incorrect? To reach a conclusion, one must examine the reasons why one heat exchanger is preferred over another, as well as whether the choice is correct based on the facts given.
Consider a hypothetical application that could make use of a variety of heat exchangers. Let's choose a plate, spiral, or tubular design and ignore any product characteristics, focusing instead on why these selections were made:
1) The first customer went for a plate heat exchanger because it was less expensive.
2) The second customer had been prejudiced towards non-traditional tubular designs but was satisfied with his or her choice.
3) Because he or she was concerned about prospective gasket issues, the third customer chose a spiral-type heat exchanger. In addition, he or she could not ensure that the maximum temperature restriction would be met.
A processor must be able to choose from a variety of heat exchanger equipment in order to match the best heat exchanger to the specific application. To make the best decision, consider both operating temperatures and pressures, the fluid qualities of the product, space, maintenance, multiproduct use on the same equipment, and, of course, price.
Heat exchangers in most processors come in a variety of shapes and sizes, including kettles, plates, tubulars, spirals, and scraped surface heat exchangers. This equipment is used in a variety of ways within these processing plants. Pasteurize, sterilise, preheat, cool, deep cool, crystallise, slush freeze, temper, gel, or polymerize can all be done with them. Let's look at each one in more detail.
Tubular Heat Exchanger
Heat Exchangers with a Scraped Surface
Price is the most important factor to consider when choosing a heat exchanger, but a processor should never put the dollars for the initial capital expenditure ahead of his or her long-term goals and requirements. The price per square foot of heat exchange area can range anywhere from $25 to $2,500. (table 1).
A processor should have a clear idea of where he or she wants to go a year from now. If he or she does, the processor should be aware of the current and future types, phases, and materials of construction necessary for the product (if it is a sensitive or complex product). Both are crucial to his or her operation's overall operational efficiencies and profitability.