The Design of a Double Pipe Heat Exchanger

CE 2.1 Project Information
Name of the project: The Design of a Double Pipe Heat Exchanger
Location of the project: Please fill
Project Duration: Please fill
Organization: Please fill
Role and Designation during the time: Team Member of the project
CE 2.2 Project Background
CE 2.2.1 Characteristics of the project
This project of The Design of a Double Pipe Heat Exchanger was my first mini
project in engineering career. The double pipe heat exchanger was made eventually for the
purpose of reducing the complexities of heat exchange. This project was executed by our
group in Zirconium Oxide Plant. The requirement of nuclear fuel was the major reason for
this project. There is a link between the cycle of PHWR or pressurized heavy water plant
reactor, LWR or light water reactor and LMFBR or liquid metal cooled fast breed reactor.
CE 2.2.2 Objectives developed for the project
The project of Design of a Double Pipe Heat Exchanger comprises of two important
objectives. The objectives are as follows:
 To make the double pipe heat exchanger
 To help the society with this heat exchanger.

CE 2.2.3 My area of work
This project of The Design of a Double Pipe Heat Exchanger was executed properly.
As the chemical engineer, my main area of work was to document the entire project. I made
sure that the project documentation was done perfectly. My other area of work in the project
was to arrange for various meetings and gatherings of the project. I did this at the end of
every week for understanding whether the project would be successful or not or whether we
are lagging behind.
CE 2.2.4 Project Group
Figure 1: People involved in the project
CE 2.2.5 My responsibilities throughout the project
I was an important part of the project. I had various important responsibilities within
the project. My first and the foremost responsibility in this project of The Design of a Double
Pipe Heat Exchanger was to document the entire project properly. I knew that if the project
report was made perfectly, the project is bound to be a success. My next responsibility was to
assist my project supervisor in the project. Another important responsibility that I had to

execute in this project was providing guidance to my juniors. I even applied my knowledge
and skills within the project for successfully completing the project.
CE 2.3 Distinctive Activity
CE 2.3.1 Engineering knowledge and skills applied in the project
I have utilized my chemical engineering skills and knowledge for the success of the
project. I knew that if I will apply my skills and knowledge in the project properly, it is
evident that the project will be a huge success. I am a hardworking person and have excellent
problem solving skills. Since I was a quick learner, I utilized my experience in this particular
project. I had also used my computer proficiency in the project, which included MS Office,
MS Project and many more. My power of critical thinking is also applied here.
CE 2.3.3 Comprehending the Theory of Project
The zirconium oxide powder was produced in ZOP. The main raw material that was
required to produce zirconium was zircon sand. This type of sand comprises of silicates as the
main impurities and hafnium as the main impurity. The zircon sand was subjected for mixing
the process with caustic soda at temperature of 6500C, and frit, formed was eventually sent to
a series of three distinct leaching tanks to remove sodium silicate. When the leaching
zirconate was washed again in plate and was framed for filter press, the impurities were
removed and alkalinity was reduced. The obtained hydrated zirconia product is dried in turbo
dryer and subjected to dissolution with nitric acid. The crude zirconium nitrate solution is
then sent for solvent extraction process and pure zirconium nitrate was produced.
Heat exchangers are a device that exchange the heat between two fluids of different
temperatures that are separated by a solid wall. The temperature gradient, or the differences
in temperature facilitate this transfer of heat. Transfer of heat happens by three principle

means: radiation, conduction and convection. In the use of heat exchangers radiation does
take place. However, in comparison to conduction and convection, radiation does not play a
major role. Conduction occurs as the heat from the higher temperature fluid passes through
the solid wall. To maximize the heat transfer, the wall should be thin and made of a very
conductive material. The biggest contribution to heat transfer in a heat exchanger is made
through convection.
The main features of the Zircalloy were as follows:
i) Good guttering
ii) Highly pyrophoric
iii) Super conductive at low temperature with niobium
iv) High refractive index in oxide form
v) Good refractive properties in oxide form
There is a list of operations carried out in ZOP. They are as follows:
i) Dissolution of Dry Powder
ii) Solvent Extraction
iii) Precipitation
iv) Repulping
v) Vacuum Filtration
vi) Drying
vii) Calcination

viii) Grinding
ix) Blending.
The major advantages are as follows:
i) The filter is continuous in operation, as the rotary drum is rotated by electric motor.
So the manpower requirement is very low.
ii) With cake consisting of coarse solids, it is possible to remove most of the liquids
from the cake before discharging.
The disadvantage is as follows:
i) The maximum available pressure difference is limited as it being a vacuum filter.
A heat exchanger can be defined as the piece of equipment that is built for the
effective transfer of heat from any one medium to the other. They are broadly utilized in
the petrochemical plants, space heating, air conditioning, refrigeration, power plants, natural
gas processing, petroleum refineries, chemical plants and sewage treatment. In a heat
exchanger forced convection allows for the transfer of heat of one moving stream to another
moving stream. With convection as heat is transferred through the pipe wall it is mixed into
the stream and the flow of the stream removes the transferred heat. This maintains a
temperature gradient between the two fluids.
Double pipe heat exchangers can be defined as the simple exchangers that are utilized
in various industries. All the heat exchangers are extremely cheap for both the design as well
as maintenance, and thus making these a better choice for the smaller industries.

Figure 2: Double Pipe Heat Exchanger
There are three parameters required to calculate the total surface area of the exchanger
required:
i) Overall Heat Transfer Coefficient.
ii) All the inlet and outlet temperatures.
iii) Fluid flow properties.
Once we calculate the area, we then proceed to accommodate that area in terms of the
geometry of the heat exchanger that is in terms of
i) Diameter of the Inner and outer pipes
ii) Length of the pipes.
iii) Geometric pattern of the pipes.
iv) Bends.

v) Number of Passes.
After the determination of all the above mentioned properties, we choose the suitable
material required for our construction of the heat exchanger. The material must offer
i) A certain degree of resistance against chemical attack.
ii) It should be replaceable if needed.
iii) It should not provide any unwanted heat transfer with the surroundings.
iv) Should be cost effective.
The double-pipe heat exchanger is one of the simplest types of heat exchangers. It is
called a double-pipe exchanger because one fluid flows inside a pipe and the other fluid flows
between that pipe and another pipe that surrounds the first. This is a concentric tube
construction. Flow in a double-pipe heat exchanger can be co-current or counter-current.
There are two flow configurations: co-current is when the flow of the two streams is in the
same direction, counter current is when the flow of the streams is in opposite directions. In
this double-pipe heat exchanger a hot process fluid flowing through the inner pipe transfers
its heat to cooling water flowing in the outer pipe. The system is in steady state until
conditions change, such as flow rate or inlet temperature. These changes in conditions cause
the temperature distribution to change with time until a new steady state is reached. The new
steady state will be observed once the inlet and outlet temperatures for the process and
coolant fluid become stable. In reality, the temperatures will never be completely stable, but
with large enough changes in inlet temperatures or flow rates a relative steady state can be
experimentally observed.
CE 2.3.4 Identified issues and their solutions
2.3.4.1 Issues

The main problem that we faced in the project was during designing the double heat
pipe exchange. The person who was given the responsibility to make the design made it
completely wrong. Since, double heat pipe exchange was the main requirement in our project,
the designing was required to be made perfect.
2.3.4.2 Solutions
I gave suggestions to my co workers for solving the issue as this was bringing delay in
the project. I made the project design myself and thus was successful in making the project
design perfect.
CE 2.3.5 Plan to produce creative and innovative work
We made a significant plan for our project. Our plan was to bring out creative and
innovative work by working mutually. We divided our work perfectly and every one carried
out their responsibility with utmost sincerity and perfection.