CONSTRUCTION OF HEAT EXCHANGER FABRICATION OF A TUBE AND SHELL HEAT EXCHANGER SYSTEM. A RESEARCH PROJECT TOPICS ON CHEMICAL ENGINEERING
There are two methods of constructing heat exchangers: Plate type. Parallel flow-the hot fluid and the coolant flow in the same direction.
Counter flow:- The hot fluid and the coolant flow in opposite direction. Cross flow: The hot fluid and the coolant flow at 90 angles (perpendicular) to each other.
The four heat exchanger parts identified were. Tube sheet shell Baffles single- pass heat exchangers have fluids that pass each other only once.
Multipass that exchangers have fluids that pass each other more than once through the use of a tubes and baffles.
Regenerative heat exchangers use the same fluid for heating and cooling. Non-regenerative heat exchangers use separate fluids for heating and cooling process.
Heat exchanger is a device whose primary purpose is the transfer of energy between fluids. (J.R. Welty and R.E Witson Fundamentals of momentary heat and mass transfer 2nd edition 1975).
There are many types of heat exchangers, namely shell-and-tube exchanger, tubular and plate exchangers, the spiral plate heat exchanger etc.
In industrial processes, heat energy is transferred by a variety of methods which includes conduction as in electric resistance, waters, conduction as in exchangers, boilers and condensers, radiation as in furnace, radiant heat dryers and by special method such as electric heating.
The heat exchanger is a very important unit or system in small scale industries and also in process industries that their design has been highly developed. Designers of heat exchanger must be constantly aware of the difference between the idealized condition for and the real conditions of the mechanical expressions of their design and its environment. The result must satisfy process operational requirements (such as availability flexibility and maintainability) and do so economically. The most common material for heat exchanger is carbon steel.
Using the simple shell and tube heat exchanger in explain the process. Hot liquid flows through the tube and cold and more viscous liquid flows through the shell. The two liquids are collected and cooled by the forced convective air which is supplied by the fan. The shell side and tube side heat transfer coefficient are of comparable important and both must be large if a satisfactory overall coefficient is to be attained. The velocity and turbulence of the shell side liquids are as important as those of the tube side flow.