Dire Dawa University
School of Mechanical And Industrial Engineering
Externship Program
Host Company:- Moha Soft Drinks Industry
Project Title:- Design and Drafting of Air Conditioning (AC) System for
Carbon dioxide Gas production room at MOHA soft Drinks Industry
Externship Duration:- 3/6/2025 – 1/10/2025
Submission Date:- September,2025
By:- Mr. Nathnael Samson
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Table of Content
CHAPTER-ONE ........................................................................................................................ 1
1.1 Back Ground of the Company ......................................................................................... 1
1.2 The Company’s Objective ............................................................................................... 2
1.3 The Company’s Vision .................................................................................................... 2
1.4 The Company’s Mission Statement ................................................................................. 3
1.5 The Company’s Organizational Structure ....................................................................... 3
1.5.1 General work flow of RGB line ................................................................................ 4
1.6 Factory Production Rooms .............................................................................................. 6
1.6.1 Co2 Facility ............................................................................................................... 6
1.6.2 Syrup Room Production Process .............................................................................. 6
1.6.3 Water Treatment Room............................................................................................. 7
1.6.4 Boiler Room .............................................................................................................. 7
1.7 The Company’s Row Materials ....................................................................................... 8
1.8 The Main Customer and Companies Market ................................................................... 8
1.9 Externship Experience ..................................................................................................... 9
1.9.1 How I get to The Externship Program ...................................................................... 9
1.9.2 The Section in which I worked at and Experience Gained ...................................... 9
1.10 None Mechanical Based activities Participated In....................................................... 15
1.11 Challenges and Problems Faced during the Program .................................................. 15
1.12 Measures to Overcome Challenges and Problems ....................................................... 16
1.13 Design and Construction Regarding safety and Economy .......................................... 16
1.14 The Overall Benefit Gained From the Externship Program ........................................ 16
1.15 Conclusion and Recommendation on the Externship Program ................................... 17
1.15.1 Conclusion: ........................................................................................................... 17
1.15.2 Recommendation: ................................................................................................. 17
CHAPTER TWO ..................................................................................................................... 18
Project Work ........................................................................................................................ 18
2.1 Abstract of Project ......................................................................................................... 18
2.2 Introduction .................................................................................................................... 18
2.2.1 HVAC System ........................................................................................................ 19
2.1.2 HVAC system selection System ............................................................................. 21
2.2.3 Basic Components of an HVAC System ................................................................ 21
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2.2.4 Classification of HVAC System ............................................................................. 22
2.3 Problem Statement ......................................................................................................... 23
2.4 Scope of The Study ........................................................................................................ 24
2.5 Significance of The Study.............................................................................................. 24
2.6 Objective of the Study ................................................................................................... 25
2.6.1 General Objective ................................................................................................... 25
2.6.2 Specific Objective ................................................................................................... 25
2.7 Designing HVAC System .............................................................................................. 26
2.7.1 Introduction ............................................................................................................. 26
REFERENCE ........................................................................................................................... 34
II
List of Figures
Figure 1 Moha Soft Drinks Industry glass and plastic bottle Products...................................... 2
Figure 2 MOHA Soft Drinks production Factory-Summit plant ............................................... 2
Figure 3 RGB line Work flow ................................................................................................... 5
Figure 4 PET line filler machine ................................................................................................ 6
Figure 5 Process Flow of PET line ........................................................................................... 6
Figure 6 Assembling parts of V-type diesel generator ............................................................ 10
Figure 7 Repairing and changing PET line conveyor belt ....................................................... 11
Figure 8 PET line Mold changing from blower machine ........................................................ 12
Figure 9 PET line labeller machine maintenance .................................................................... 13
Figure 10 Changing RGB filler machine parts ........................................................................ 14
Figure 11 Air conditioning system [1] ..................................................................................... 20
Figure 12 a) outside view of Co2 production room b) inside of Co2 room .............................. 27
Figure 13 LED light inside the CO2 gas production room ...................................................... 30
Figure 14 a) Machine lay out b) Recorded heat generated by machines ................................. 31
III
List of Tables
Table 1 RGB line machines and their function .......................................................................... 4
Table 2 PET line machine parts with functions ......................................................................... 5
Table 3 Transferable knowledge and skills gained at MOHA soft drinks industry................. 16
Table 4 Comparison of central and local HVAC systems [2] ................................................ 22
Table 5 Room Size ................................................................................................................... 27
Table 6 Essential machines and heat they emit to the atmosphere .......................................... 32
IV
CHAPTER-ONE
1.1 Back Ground of the Company
Summit partners PLC is an American company that opened a branch investment of about
us$100 million in Ethiopia in 1999 G.C. Summit partners PLC was an international investor
with a wide range of manufacturing projects planned in Ethiopia. The first project was
summit beverages, summit engineered plastic and summit glassworks in Addis Ababa. The
company has acquired 100,000 square meters of land for the construction of the above three
factories at Meri Luke. The beverage plant started its production with seven flavors of soft
drinks and mineral water. It operated under franchise agreement obtained from Cadbury
Schweppes, a developer of soft drink flavors for 200 years, who sells its products in 185
countries around the world. The bottling line machinery was designed, manufactured and
installed by central bottling international Ltd. from the United Kingdom. CBI maintained the
highest of standards and provided summit with the most advanced technology in the soft
drinks industry in Ethiopia. There are three production lines.

The first line produces beverages in standard returnable 300ml.glass bottles.

The second line, which was the first of its kind in Ethiopia, used to produce nonreturnable one litter plastic bottles (PET bottles). This line has now been replaced by a
new and modern line so as to fulfill the growing needs of market.

The third line produces packaged drinking water in 20Liter containers.
However in 2003 Summit Beverage could not resist the competition between other soft
drinks (like Coca Cola &Pepsi Cola), Schweppes became out of market after five production
years. Currently, the factory is sold to MOHA SOFT DRINKS INDUSTRY S.C. and the
mainly engaged in producing Pepsi cola, Miranda orange, 7 up, Miranda Tonic and Cool
water. Glass and plastic bottle products are seen on Figure 1 below.
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Figure 1 Moha Soft Drinks Industry glass and plastic bottle Products
MOHA Soft Drinks Industry S.C. was formed and registered under the commercial code of
Ethiopia on the 15th of May 1996.This company was formed after the acquisition of Pepsi
Cola plants namely Nifas silk, Tekilehaimanot, Gonder and Dessie which were owned by the
government. After some years back, it has acquired the former Bure, too. Recently the
company was keeping expanding the industry by installing new machineries at SUMMIT
plant and it has inaugurated another modern plant at Awassa called Awassa Millennium
plant. And also MOHA Mekele plant which is under taking in erection activity is among the
expansion.
Summit MOHA plant established in 2003, has 460 permanent employees and producing
MOHA’s products with three plants like:- 300ml returnable glass bottle, 0.5ml up to 1.8ml
non-returnable plastic bottle and carbon dioxide plant.
Figure 2 MOHA Soft Drinks production Factory-Summit plant
1.2 The Company’s Objective
The business purposes of the company as stipulated in its policy manual are:



To carry on beverage manufacturing, processing and bottling.
To manufacture, sell and distribute Carbon dioxide.
Manufacture and/or distribute beverage items.
To carry on any other business which may seem to the company capable of being
conveniently carried on in connection with any business of the company, Or
calculated directly or indirectly to enhance the value of or render profitable any of the
company’s property.
1.3 The Company’s Vision

The company envisions that it will be a dynamic and innovative force in the
Ethiopian beverages market.
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


It will be known for distinctive, high quality products packed by creative marketing
and compelling advertising campaigns.
It will be distinguished as the company that listens and delivers the utmost in
personalized service.
It will be financially successful, socially responsible, and commercially prominentand industry leader for the free- market era in Ethiopia.
1.4 The Company’s Mission Statement
The company states that its first responsibility and primary focus is to both satisfy and delight
the community of end users whom it exists to serve; to fulfill their needs and wants; and to
improve their quality of life. It says that knowing the path to the end users lies through the
retail and wholesale trades and its priority that to listen and respond to the needs and wants of
its retail wholesale trade partners.it will treat retail and wholesale trade expansions of itself. It
will lavish the highest levels of respect, courtesy, and service. In addition to this, it gives a
high priority to its employees. there is a saying in its employee manual stating,‖…without a
happy, motivated, and dedicated employees, there can be no success.‖
1.5 The Company’s Organizational Structure
MOHA Summit factory operated by operation manager who is appointed by the chief
executive officer (C.E.O.) OF MOHA SOFT DRINKS INDUSTRY S.C. The operation
manager of the company mainly is empowered to:
Direct, plan, coordinate, organized, control, and administer the over-all operation of
the company.

hire and fire personnel

Represent the company in all fields of activities.

Conduct SWOT analysis and set attainable goals with appropriate strategy.

Ensures assets are efficiently managed and controlled.

Executes over all plant objectives and measure performance.

Chairs management committee meetings of the plant.

Prepares and submits to the C.E.O. the work program and budget of the plant,
implement, and sum up on approval and reports on the performance and financial
operations of the plant.
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Up on approval and reports on the performance and financial operations of the plant. The
activities of the company reporting to the operation manager are grouped into the following
functions.
1. Finance department
2. Human Resource department
3. sales/Marketing department
4. Technical Service department 5. production department
5. Quality control and Food safety department.
6. Procurement and store/supplies department. The departments’ heads of the plant
mainly deal with conceptual activities to support the plant general manager/operation
manager. The details of their duties and responsibilities are stipulated in the
company’s Job Descriptions Manual.
1.5.1 General work flow of RGB line
First de-crater machine takes out the empty glass from the create box and puts on the
conveyor belt. The conveyor belt moves the empty glass bottles to the bottle washer in other
side the crate goes to crate washer. If washing of empty bottles process finished there is
inspection for not cleaned and broken bottles. After inspection the empty bottles transferred
to filler machine, the next operation is crowning of the bottles. Then the bottles moved to date
coding machine a machine that is used to write the production and expiration dates. After
date coding the filled bottles arrive at full bottle inspection section and inspected for over fill
under fill, and uncrowning. The next section is the packing section first there is full bottle
inspection for over fill, under fill, and uncrowning. Then the bottles moved to the re-crater
machine it is used to put the full bottles into crate box it is the same as de-crater machine but
their function is Reversible. Here the table 1 shows different RGB lines with their function.
Table 1 RGB line machines and their function
Type of machine
De-crater
Bottle washer
Crate washer
Filler machine
Para- mix
Machine Function
Takes out empty glass from the crate box
Used cleans and sanitized returnable bottles that have been brought
back from customers
Used to wash empty crate
Filling the empty glass with the soft drink (The production capacity for
RGB line is 24000 bottles per hour.
Used for processing and preparing the product mix (soft drink).Three
components come through the pipe these are the water, the syrup and
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Date coder
Re-crater
Crowner
CO2 and mixed in the line
Used to write the date of production and the expiration of soft drink
Takes in the glass filled with soft drink to the crate box
Closing the glass filled with soft drink by crown cork
Co2
Figure 3 RGB line Work flow
Table 2 PET line machine parts with functions
Type of machine
Preform
Oven
Blow
Filler
Labeller
Pet dryer
Buffer
Packer
Machine Function
silo Hold and transfer performs to the oven through conveyor
Used to heat the performs at the required temperature before
molding process started
mold Change the preform into PETs
Filling the empty glass with the soft drink into PETs
Used to attach the label information of the beverage on the
surface of pet.
dry the pet before labelling
close the glass filled with soft drink
Used to arrange the pet filled with soft drinks into groups that are
easy for transportation and handling.
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Figure 4 PET line filler machine
Figure 5 Process Flow of PET line
1.6 Factory Production Rooms
1.6.1 Co2 Facility
Co2 facility process is one of the significant utility sections, which is prepared inside the Co2
room in either gaseous or liquid form with a standard measurement which is controlled by
observing the pressure gauge on the top side of Co2 tanker. The desired and well prepared gas
is transported via to the filler machine through a transmission pipe. The filler machine is
responsible to pressurized and mix with soft drink.
1.6.2 Syrup Room Production Process
The syrup preparation process and the sugar dissolving process are the most significant
process for the company. The dissolving process is made by using direct raw materials like
sugar, activated carbon water, and chemical whiffed powder. The sugar is supplied in sacks
on pallets the sugar is then fed into supply hopper by hand. An inclined conveyor worm is
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installed to feed the sugar out of the hopper to the dissolving tank. The sugar feed system and
storage facility must be in a dry room in which the temperature can be controlled. As
immediately as the sugar is entered into the sugar dissolving tank a pipe tube containing
steam having temperature ranging 85-90 degree Celsius inside will automatically start
rotating to dissolve the sugar. Then the dissolved sugar is transferred to the next step for
filtration process. A filter tank having filter sheets will filter the dissolved sugar and trap
unnecessary particles passed with the dissolved sugar.
1.6.3 Water Treatment Room
The water treatment is a process performed in reverse osmosis process. It has two ways
where one is made by using direct chemical reactant raw materials and other is by ion
exchange process where the hardness of sodium chloride salt is exchanged for an equivalent
amount of sodium which contains no hardness properties. The water softening process is
available for washing machine, steam boiler, filler machine as well as crate washer machine.
The reservoir tank supplies water towards the water treatment section. The formation of
treated water that are used for the product component in the syrup room which are going to
filler machine begins by the addition of chemical raw materials like chlorine, aluminum
sulphate, calcium chloride, and lime inside the water tank is too high. These raw materials are
agitated by a motor with a normal frequency speed checked by the chemists during
preparation. These chemicals are pushed toward the reaction tank through a thin hose from
their storage tanks. The operators ensure the quality of the water by draining a sample
through discharging pipes water. The next work process goes to a device called polisher
which contains a pressed filter inside it that are used to purify the solid content of the treated
water. Finally the treated water is pushed by a product pump where the valve manifold panel
supplies the product water to be dosed with the product component.
1.6.4 Boiler Room
The basic function of this room is boiling water and changes to steam. Steam pressure, oil
furnace and height of water level are regulated automatically. Thermal energy is transported
to the water inside the boiler body by means of heating. The water grows warmer and
vaporizes the steam so the pressure in the boiler rises. Transported through pipe to bottle
washer, syrup room, crate washer, and CIP machine (clean in place, it is used to clean and
sterilize internal parts of the machine)
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1.7 The Company’s Row Materials
According to the flow system, imported raw materials,(such as bottles, various chemicals,
sugar, pepsi -cola concentrates, Miranda concentrate, 7 up concentrate, Miranda concentrates)
and locally produced raw materials, (such as plastic cases, crown cork, various chemicals,
sugar, carbon dioxide gas, labels and bottles)are put into stores to transport them directly into
the manufacturing system through forklift.
 For Raw materials or inputs for bottle beverage:

Treated water

sugar

carbon dioxide(co2)

Returnable glass bottles (RGB)

Crown cork

liquid and dry ingredient

pallets

crate
 For PET uses plastic bottles the raw materials or the inputs are:

Treated water

sugar

carbon dioxide(co2)

perform

closure

liquid and dry ingredient

pallets

security sleeve

shrink wrap/film
The raw materials came from different countries. The concentration and the liquid ingredient
came from Ireland under the authority of Pepsi international. The crown and the closure come
from U.A.E. (Dubai) and the preform from Belgium and it also manufactured locally.
1.8 The Main Customer and Companies Market
MOHA holds 52%of the market share in soft drinks industry in the country. With an
expansion and replacement of obsolete machinery, production capacity of the plant has
8
increased substantially. MOHA, in addition to the initial purchase price of the soft drinks
factory, has invested Birr 8 million for expansion of new projects, Birr 153 million for
refurbishment and replacement of existing plants and Birr 241 million for marketing,
infrastructure, excluding advertisement and sponsorship expense. Also, a significant growth
over the years of production, sales, and profitability due to reorganization of operations has
been achieved. Productivity has improved tremendously with major cost saving and has
insured a regular supply of high quality products. It has also succeeded in reaching new
market areas across the country.
1.9 Externship Experience
1.9.1 How I get to The Externship Program
The externship program was aimed to equip mechanical engineering staff members with an
abdicate theoretical and practical knowledge. The program facilitates one semester (6 month)
training and learning environment at different manufacturing factories and companies. As a
mechanical engineering staff member I also the part of this program. By March 3, 2025 I
brought a letter of collaboration from my department dean to MOHA’s department of human
resources. It is when I officially got accepted at the company and begin my training where it
lasted for the next six months.
1.9.2 The Section in which I worked at and Experience Gained
During the externship period, I have been working in technique, production and ware house
departments. The technique department is divided into mechanical and electrical sections. As
a mechanical engineering staff member, I gained in the mechanical maintenance team. The
production department mainly divided into three lines RGB, PET, and Co2 lines. Which has
helped me see and observe the production processes and related technical problems as an
engineer. It is my understanding that the MOHA soft drinks industry mechanical engineering
department maintenance crew mainly focuses on preventive maintenance. Which the
factories mechanics were tasked to regular checkups and maintenance any potential problems
that may affect the production process of the company. Some of the maintenance activates I
have participated ate listed below.
Repairing Combustion Generator Cylinder
By the time I was there the V-type diesel engine generators combustion cylinder for PET line
backup generator was crucially damaged. The cylinder lining were highly damaged by the
9
fatigue between the cylinder head and cylinder wall lining. This continuous fatigue between
the two parts caused the cylinder walls to wear out over time, causing the high crank noise,
overheating and miss alignment on the crank shaft. So to maintain this problem a moulding
repaired was done on the inner lining of the cylinder wall. After moulding the inner lining of
the combustion cylinder the piston along with connecting road was inserted in the
combustion chamber maintain central alignment. The activities I talk part in maintain the
centrality and assembling back the generator parts. Figure 6 shows some of the activities I
took part in assembling the generator parts.
Experience Gained:

Hands-on experience with internal combustion engine components and maintenance
procedures

Improved diagnostic skills for mechanical faults in high-capacity industrial generators

Gained knowledge of safety protocols during heavy equipment repair

Enhanced teamwork and communication skills by collaborating with multidisciplinary
technicians.
Figure 6 Assembling parts of V-type diesel generator
Repairing PET line Conveyor Belt
During my time at Moha Soft Drinks Industry, I actively participated in the replacement of a
worn-out conveyor belt on the PET production line. This task involved working alongside
10
maintenance technicians to dismantle the old belt, inspect rollers and motor systems, and
install a new conveyor belt with proper alignment and tensioning.
Experience Gained:

Gained hands-on experience in conveyor belt systems used in beverage production
lines.

Learned practical troubleshooting techniques for mechanical faults in continuous
production systems.

Enhanced my teamwork and communication skills while working closely with
experienced technicians.

Understood the importance of preventive maintenance and safety protocols in a highspeed production environment.

Developed a better appreciation for minimizing production loss through efficient
repair processes.
Figure 7 Repairing and changing PET line conveyor belt
Changing PET line blow Mold from blower Machine
At Moha Soft Drinks Industry’s PET production line, I actively participated in the mold
change process of the blow molding machine, supporting smooth transitions between
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different bottle sizes—specifically from 1-liter plastic bottle molds to 0.5-liter and 2-liter
molds, and vice versa.
Experience gained:

Assisting in the mechanical disassembly and reassembly of the mold units.

Ensuring proper alignment and positioning of new molds to maintain dimensional
accuracy and bottle quality.

Supporting adjustments to machine settings such as preform heating, stretch-blow
parameters, and air pressure to suit the new mold size.

Collaborating with technicians and production supervisors to minimize downtime and
ensure a safe and efficient changeover.

Performing basic inspection and trial runs after each change to confirm proper
functionality and quality compliance.
This experience strengthened my understanding of PET processing, equipment handling, and
efficient production changeovers in a fast-paced beverage manufacturing environment.
Figure 8 PET line Mold changing from blower machine
Repairing PET line labeler Machine
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During my time at Moha Soft Drinks Industry, I participated in the maintenance and repair of
the PET line labeler machine, which plays a critical role in the bottling and labeling process.
The labeler had experienced frequent misalignment and mechanical jamming, which affected
production efficiency.
My involvement included assisting the maintenance team in disassembling key mechanical
components, identifying worn-out parts, and helping with their replacement and realignment.
I also contributed to troubleshooting the pneumatic system and ensured that sensors and
control units were properly calibrated. Through this hands-on experience, I gained valuable
insights into the operational mechanics of high-speed labeling equipment, preventive
maintenance practices, and teamwork in an industrial production setting.
This experience improved my technical diagnostic skills, enhanced my understanding of
industrial automation, and reinforced the importance of precision and coordination in
minimizing downtime in manufacturing environments.
Figure 9 PET line labeller machine maintenance
Changing RGB line filler Machine Parts
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During my time at Moha Soft Drinks Industry, I actively participated in the maintenance and
upgrade task of changing filler machine parts at the RGB (Returnable Glass Bottle)
production line. This activity is done whenever there is a product change. i.e Pepsi to seven
ups, Miranda to Pepsi and all in reverse. During this time filler machine parts such as glass
line bottle guide, drink filler road and bottle stands are changed
This activity was part of a scheduled maintenance operation aimed at improving the
efficiency, accuracy, and hygiene standards of the bottling process.
Experience Gained:
Assisting in the safe disassembly and removal of the worn or out dated bottle stands
from the filler unit.

Preparing and aligning the new bottle stands to ensure proper fitment and mechanical
integrity.

Collaborating with maintenance engineers and line technicians to conduct trial runs
and verify the smooth operation of the filler machine after replacement.

Following strict safety and sanitary protocols throughout the task, given the foodgrade nature of the product.
Figure 10 Changing RGB filler machine parts
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1.10 None Mechanical Based activities Participated In
Beside mechanical based activities I engaged with Moha mechanical department staff
members, I laso has the chance to daily production process activates, some of the activities
are listed below.
1. Participating on the palletizing process for the packed cool water.
2. Participating in changing Roller bearings for blow molding transfer star grippers that
receive from blow mold and transfer to filler,
3.The preform feeder unscramble roller recovery belt driving pulley or belt return motor
drums the internal bearing was failed and it have again a noise, therefore we change the
bearing when the production is stopped for maintenance.
4. Engagement in assembled the caustic buffer tanker caustic agitator by fitting the motor
5. Participating in the format change for blow mold and the Transfer stars. The format was
changed from 0.5 kool carbonated water to 1.5 L Mirenda orange.
6. Participating in changing and maintaining of the compensation seal for blow molding
machine mold number.
7. Changing and lubrication process of ball bearing which is found in labeller machine out
feed star
8. Changing and maintaining of the filling machine main drive motor by the reserve motor
because of the pulley and the motor shaft is worn out and it create unwanted noise and
heating.
1.11 Challenges and Problems Faced during the Program
Since I was new to the factory some challenges has faced me during my Externship program .
some of the challenges I have come across includes the following.
1) Some machines lock operation manual so it was difficult for me accesses easily understand
there working procedure and find potential mechanical problems to solve.
2) Most factory machine operators lack sufficient knowledge behind inner working process
of the companies mechanical machines. Only I was able to understand the outer working
process of machines.
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1.12 Measures to Overcome Challenges and Problems
For the six months I stayed at the company I have gone through deferent production line
works and mechanical maintenance activities. Even though I have gained a quit
understanding to the working process of deferent production lines, I also encountered few
challenges as mentioned in previous section of the report. To overcome those challenges I
have taken the following measures.
1. Create a close contact with company supervisors in mechanical department and make
them assign me a person in charge with enough understanding of deferent production
sectors.
2. Get blue print, operation manuals and previously conducted researches to have a clear
understanding of the production process.
1.13 Design and Construction Regarding safety and Economy
The design and construction of Moha Soft Drinks Industry according to safety the factory use
common PPE (Personal Protective Equeipment) to protect the worker from accident and all
worker use this principle and also all workers must use their safety material like (safety
shoes, clothes, gloves …) according to economy the factory.
1.14 The Overall Benefit Gained From the Externship Program
As the program is aimed to equip mechanical engineering staff members with skills and
knowledge of different production process and have a first-hand experience on how the
production process at different companies run. Having to acquire those skills and knowledge
will narrow the knowledge gap between theories and practical skill. In addition it will help
staff members to influence there students with the sense of manufacturing process. Some of
those skills and knowledge are listed in Table 3.
Table 3 Transferable knowledge and skills gained at MOHA soft drinks industry
No.
Skill / Knowledge Gained
1
Hands-on Maintenance
Techniques
2
Industrial Safety and Hygiene
Standards
3
Understanding of Beverage
Production Machinery
4
Troubleshooting and ProblemSolving
5
Preventive and Corrective
How It Can Be Transferred to Students
Demonstrating real-world repair and maintenance
practices on mechanical systems.
Teaching safety protocols and hazard prevention in
manufacturing environments.
Explaining machine operation principles like
fillers, conveyors, and cappers.
Guiding students in diagnostics and solutions for
mechanical failures.
Teaching maintenance planning and
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6
7
8
9
10
Maintenance Procedures
Team Collaboration in Industrial
Settings
Use of Mechanical Tools and
Measurement Instruments
Real-time Process Monitoring
and Quality Control Practices
Production Line Optimization
Techniques
Technical Documentation and
Reporting
implementation strategies.
Emphasizing communication and teamwork
through group projects or lab work.
Demonstrating accurate usage and calibration of
industrial tools.
Introducing quality assurance principles and
statistical process control.
Teaching methods to improve efficiency, reduce
downtime, and increase output.
Encouraging students to write maintenance reports
and technical logs as part of assignments or lab
work.
1.15 Conclusion and Recommendation on the Externship Program
1.15.1 Conclusion:
The externship program at MOHA Soft Drinks Industry provided a valuable opportunity to
bridge the gap between academic theory and industrial practice. As a mechanical engineering
lecturer, I was able to gain practical exposure to modern manufacturing systems, especially in
the beverage industry. The hands-on experience with machinery operation, maintenance
routines, safety protocols, and production line management significantly enriched my
technical and pedagogical understanding. This experience will directly enhance the quality of
my teaching, enabling me to deliver more practical, industry-aligned education to my
students.
1.15.2 Recommendation:
I strongly recommend that such externship programs be regularly incorporated into
professional development plans for engineering educators. They not only improve teaching
effectiveness but also help align curriculum content with current industry standards. It would
be beneficial for academic institutions and industries to collaborate more closely to create
structured, skill-focused externship opportunities for faculty members. Expanding and putting
special focused effort on the program and expanding scope of such programs can further
maximize the impact on both teaching and learning outcomes.
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CHAPTER TWO
Project Work
Designing Air Conditioning System (AC) for Carbon Dioxide (Co2) Production Room
2.1 Abstract of Project
This project focuses on the design and implementation of an efficient air conditioning (AC)
system for the carbon dioxide (CO₂) production room at MOHA Soft Drinks Industry. The
CO₂ production room operates under high thermal loads due to heat-generating equipment
such as compressors, scrubbers, and reactors. Maintaining an optimal temperature and
humidity level is critical not only for equipment performance and energy efficiency but also
for the safety of workers and the stability of CO₂ production.
The project began with a comprehensive analysis of the room’s heat load using
thermodynamic principles, considering internal heat sources, occupancy, lighting, and
external influences. Based on the cooling load calculations, an appropriate AC system was
selected and designed, ensuring it meets industrial ventilation standards and environmental
safety regulations. Special attention was given to air circulation patterns, filtration systems,
and redundancy to maintain system reliability.
The proposed design aims to reduce operational downtime, improve air quality, and enhance
overall process efficiency. This project also provides a practical learning opportunity for
integrating HVAC design principles with real industrial applications, offering insight into
energy management and process-specific environmental control.
2.2 Introduction
The science and practice of creating a controlled climate in indoor spaces is called air
conditioning. Man inhabitants all the parts of the world-from Antarctica to the African
deserts. Only in a very few favoured areas of the earth’s temperate zone can people live and
work comfortably round the year without any air conditioning. From the earliest times,
artificial cooling has been recognized as desirable. In every era people have invented
primitive methods for cooling strictly as a luxury rather than as a necessity- snow, ice, and
cold water when available were used for small-scale cooling. Atmospheric evaporation of
water was also used crudely without much understanding of the underlying principles. The
primitive method of heating for comfort, was building open fires in caves and tents.
18
Fireplaces in medieval Europe were hardly an improvement. Ancient Romans circulated
warm air in hollow floors or walls to provide radiant heating. This was an improvement over
the localized radiation from a fireplace[1].
Attempts to control indoor temperatures began in ancient Rome, where wealthy citizens took
advantage of the remarkable aqueduct system to circulate cool water through the walls of
their homes. The emperor Elagabalus took things a step further in the third century, building
a mountain of snow—imported from the mountains via donkey trains— in the garden next to
his villa to keep cool during the summer. Marvellously inefficient, the effort presaged the
spare-no-cost attitude behind our modern-day central air-conditioning systems. Even back
then some scoffed at the concept of fighting heat with new-fangled technologies. Seneca, the
stoic philosopher, mocked the "skinny youths" who ate snow to keep cool rather than simply
bearing the heat like a real Roman ought to.
Such luxuries disappeared during the Dark Ages, and large-scale air-conditioning efforts
didn't resurface in the West until the 1800s, when well-funded American engineers began to
tackle the problem. In the intervening centuries, fans were the coolant of choice. Hand fans
were used in China as early as 3,000 years ago, and a second-century Chinese inventor has
been credited with building the first room-sized rotary fan (it was powered by hand).
Architecture also played a major role in pre-modern temperature control. In traditional
Middle Eastern construction, windows faced away from the sun, and larger buildings featured
"wind towers" designed to catch and circulate the prevailing breezes[1].
2.2.1 HVAC System
Heating, ventilation, and air conditioning (HVAC) system is designed to achieve environmental requirements of the comfort of occupants and a process. HVAC systems are more
used in different types of buildings such as industrial, commercial, residential and
institutional buildings. The main mission of HVAC system is to satisfy the thermal comfort
of occupants by adjusting and changing the outdoor air conditions to the desired conditions of
occupied buildings. Depending on outdoor conditions, the outdoor air is drawn into the
buildings and heated or cooled before it is distributed into the occupied spaces, then it is
exhausted to the ambient air or reused in the system. The selection of HVAC systems in a
given building will depend on the climate, the age of the building, the individual preferences
of the owner of the building and a designer of a project, the project budget, the architectural
design of the buildings [2].
19
An air conditioning system, including a condenser for condensing a refrigerant, a first
expansion device for throttling the refrigerant passed through the condenser, a second
expansion device for throttling the refrigerant passed through the first expansion device, an
evaporator for evaporating the refrigerant passed through the second expansion device, a
compressor for compressing the refrigerant passed through the evaporator and the refrigerant
injected after branched between the first expansion device and the second expansion device,
and a control unit for detecting a value of at least one operating parameter and determining a
target opening degree of the first expansion device on the basis of a stored set value
corresponding to the detected value of the operating parameter.
Figure 11 Air conditioning system [1]
HVAC systems compressed AC system and it can be classified according to necessary
processes and distribution process . The required processes include the heating process, the
cooling process, and ventilation process[3]. Other processes can be added such as
humidification and dehumidification process. These process can be achieved by using
suitable HVAC equipment such as heating systems, air-conditioning systems, ventilation
fans, and dehumidifiers. The HVAC systems need the distribution system to deliver the
required amount of air with the desired environmental condition. The distribution system
mainly varies according to the refrigerant type and the delivering method such as air handling
equipment, fan coils, air ducts, and water pipes.
20
2.1.2 HVAC system selection System
System selection depends on three main factors including the building configuration, the climate conditions, and the owner desire [3]. The design engineer is responsible for considering
various systems and recommending more than one system to meet the goal and satisfy the
owner of a building. Some criteria can be considered such as climate change (e.g.,
temperature, humidity, and space pressure), building capacity, spatial requirements, cost such
as capital cost, operating cost, and maintenance cost, life cycle analysis, and reliability and
flexibility.
However, the selection of a system has some constraints that must be determined. These constraints include the available capacity according to standards, building configuration,
available space, construction budget, the available utility source, heating and cooling building
loads.
2.2.3 Basic Components of an HVAC System
basic components or equipment of an HVAC system that delivers conditioned air to satisfy
thermal comfort of space and occupants and the achieve the indoor air quality are listed
below [3]:
A. Mixed-air plenum and outdoor air control
B. Air filter
C. Supply fan
D. Exhaust or relief fans and an air outlet
E. Outdoor air intake
F. Ducts
G. Terminal devices
H. Return air system
I. Heating and cooling coils
J. Self-contained heating or cooling unit
K. Cooling tower
L. Boiler
M. Control
N. Water chiller
O. Humidification and dehumidification equipment
21
2.2.4 Classification of HVAC System
The major classification of HVAC systems is central system and decentralized or local
system. Types of a system depend on addressing the primary equipment location to be
centralized as conditioning entire building as a whole unit or decentralized as separately
conditioning a specific zone as part of a building. Therefore, the air and water distribution
system should be designed based on system classification and the location of primary
equipment. The criteria as mentioned above should also be applied in selecting between two
systems. Table 4
shows the comparison of central and local systems according to the
selection criteria [3,4].
Table 4 Comparison of central and local HVAC systems [2]
Criteria
Centralized System
Decentralized System
Temperature, humidity, and •Fulfilling any or all of the Fulfilling any or all of the
space pressure requirements
design parameters
design parameters
Capacity
Capacity requirements
•Considering
HVAC •Maximum
capacity
is
diversity factors to reduce the required for each equipment
installed equipment capacity
•Equipment sizing diversity
•Significant first cost and is limited
operating cost
Redundancy
•Standby equipment is
•No
accommodated for
equipment.
backup
or
standby
troubleshooting and
maintenance
Special requirements
•An
equipment
located
room
outside
is •Possible of no equipment
the room is needed
conditioned area, or adjacent •Equipment may be located
to
or
remote
from
the on the roof and the ground
building
adjacent to the building
•Installing
secondary
equipment for the air and
water distribution which
requires additional cost
22
First cost
•High
capital
cost • Affordable capital cost
Considering
-longer equipment services
life to compensate the high
capital cost
Operating cost
•More
significant
energy •Less
efficient primary equipment
•A
proposed
energy
efficient
primary equipment
operating • Various energy peaks due
system which saves operating to occupants’ preference
• Higher operating cost
cost
Maintenance cost
•Accessible to the equipment •Accessible to equipment to
room for maintenance and be located in the basement or
saving
equipment
in the living space. However, it
excellent condition, which is difficult for roof location
saves maintenance cost
Reliability
due to bad weather.
•Central system equipment •Reliable
can be an attractive benefit although
equipment,
the
estimated
when considering its long equipment service life may
service life
be less
Placed
Flexibility
•Selecting standby equipment •Placed
in
numerous
to provide an alternative locations to be more flexible
source of HVAC or backup
2.3 Problem Statement
MOHA Soft Drinks’ production process requires strict environmental control to ensure
consistent product quality, hygiene, and compliance with food and beverage industry
standards [5]. The existing natural ventilation and fan control measures in the production
room are insufficient to maintain stable temperature, humidity, and air purity levels,
particularly during peak production periods and seasonal temperature variations. The
variation of temperature experienced inside the Co2 gas production room creates different
temperature zones inside the room. As moving from the room iterance towards the machines
23
(boiler, condenser, and scrubber), a clear temperature increases is sensed. Which makes it
less confortable for machine operators.
Lack of HVAC system can lead to:

Fluctuations in product quality due to inconsistent processing conditions.

Increased risk of microbial contamination from uncontrolled humidity and poor air
filtration.

Reduced employee comfort, potentially lowering productivity and increasing health
risks.

Higher energy costs due to inefficient thermal management.
Without a properly designed and optimized HVAC system, the production facility faces
operational inefficiencies, potential non-compliance with hygiene regulations, and increased
production costs, ultimately affecting the company’s competitiveness and profitability.
2.4 Scope of The Study
This study focuses on designing a heating system for MOHA soft drinks industry Co 2
production room. The study includes the following factors.
1.
2.
3.
4.
Assessment of Heat generated inside production room
Design of suitable HVAC system for the room
System Layout & Integration (CAD design)
Economic and Feasibility Analysis
2.5 Significance of The Study
The design of a Heating, Ventilation, and Air Conditioning (HVAC) system for the MOHA
Soft Drinks Co2 gas production room holds substantial importance for operational efficiency,
product quality, and worker safety. This study provides solutions that directly impact the
performance and sustainability of the production process.
1. Operational Efficiency

A well-designed HVAC system enhances process reliability by maintaining
stable environmental conditions, reducing downtime caused by overheating,
condensation, or poor air quality[5].
24

Efficient heat recovery and airflow management lower energy consumption
and operational costs[6].
2. Employee Comfort and Productivity

Maintaining appropriate thermal comfort and air quality improves worker
health, safety, and productivity within the production environment.
3. Regulatory Compliance

Supports adherence to national and international standards (such as HACCP,
ISO 22000, and local occupational health regulations) required for beverage
manufacturing facilities[6].
4. Long-Term Cost Savings

Optimized system design minimizes maintenance requirements, extends
equipment lifespan, and lowers overall lifecycle costs.
2.6 Objective of the Study
2.6.1 General Objective
The main objective of this study report is to design an HVAC system for MOHA soft drinks
industry Co2 production room. By considering all the parameters needed to design the system
and ASHRAE (American Society of Heating, Refrigerating, and Air-Conditioning Engineers)
standard.
2.6.2 Specific Objective
The specific objective of the study includes the following points
 To analysis internal and external heat generated inside and outside the Co2
production room.
 To select suitable type of HVAC system that can create a suitable environment
within the production room.
 To propose HVAC system machine requirements.
 To design HVAC system layout using AUTOCAD software.
25
2.7 Designing HVAC System
2.7.1 Methodology
Heating, Ventilation, and Air Conditioning (HVAC) systems play a crucial role in ensuring
optimal indoor environmental quality, energy efficiency, and occupant comfort in both
industrial and commercial settings. The design of an HVAC system is a multidisciplinary
process that involves integrating thermodynamic principles, fluid mechanics, heat transfer,
and control systems to achieve the desired temperature, humidity, and air quality levels. A
well-designed HVAC system not only enhances operational productivity but also reduces
energy consumption, minimizes environmental impact, and ensures compliance with relevant
safety and health standards[7].
In the context of modern industrial operations, such as beverage production, precise
environmental control is essential to maintain product quality and protect sensitive
equipment. This study focuses on the systematic design of an HVAC system tailored to meet
specific functional requirements, considering factors such as load calculations, equipment
selection, energy optimization, and system reliability. By applying advanced engineering
analysis and sustainable design strategies, the project aims to deliver a cost-effective and
efficient HVAC solution that aligns with both operational needs and environmental
responsibilities[8]. In order to came up with suitable type of HVAC system the amount of
heat circulating inside the room must be known. The total heat can be classified into two.
1. Heat generated inside of the Co2 gas production room (Stored heat).
2. Additional heat migrating from outside towards the room (External heat)
1. Analysing Heat stored Inside the Production Room
Inside the Co2 gas production room heat is a heat generated due to the area and volume of the
production room. This is called a stored heat. To analyse this heat the room geometry (area
and volume) must be known. Unfortunately the blue print for the production room is not
properly recorded. So manual measurement has to be done to determine the volume of the
room.
26
A
B
Figure 12 a) outside view of Co2 production room b) inside of Co2 room
The manually measured geometry of the production room is as shown in the following table.
Table 5 Room Size
Room size
Length
Width
Height
Area
Volume
Measurement in meters (m)
30.5
20.4
4.5
610m2
2745 m3
According to ASHRAE 62.1 standard with a room size of is assumed to generate 150 w/m2 of
heat. So to determine the total heat generated within this geometry we use the following
equation.
Qr=AxQa
Where Qr is the total stored room
A is area of the production room
Qa is the ASHRAE standard stored heat
Qr=150m2 x 280 w/m2
91500 w =91.5kW
A total of 429.016kW of stored heat is found inside the production room.
2. Analysis of additional heat inside the production Room
27
In beverage manufacturing facilities, such as soft drink production plants, the thermal
environment within the production room is influenced not only by ambient conditions but
also by a variety of internal heat sources. These internal gains often referred to as additional
heat[7]. it is generated by people, machinery, lighting, process equipment, and the products
themselves during processing. Unlike envelope loads, which depend primarily on outdoor
temperature and building insulation, additional heat originates from activities and equipment
inside the space and can significantly increase the cooling demand[7].
Inside the Co2 gas production room there are machines such as boiler, fillers, condenser,
compressors, and gas storage tanks those releases sensible and latent heat into the workspace.
Personnel engaged in production contribute metabolic heat, while lighting systems and motor
inefficiencies further add to the thermal load. Process operations may also introduce warm
products into the room, which cool to ambient temperature, transferring heat to the air.
In the following section of the study additional heat sources are analysed and generated heat
are calculated.
1. Additional heat due to occupants
Additional heat generated by occupant is a heat generated by workers and machine operators
within the production room. Those heats are mainly produced by means of conduction and
radiation means of heat transfer. There are two types of heats in this cause known as sensible
and latent heat. Calculating the sensible and latent heat produced by a person
involves understanding the body's heat production through metabolism and its dissipation
through various mechanisms. Sensible heat is the heat we feel, directly affecting temperature,
while latent heat is associated with changes in humidity, specifically evaporation of
sweat. The proportions of each are influenced by activity level and environmental
conditions[9,10].
Sensible Heat
 Definition:- Heat that causes a change in air temperature without
changing its moisture content[9].

Effect: Raises the dry-bulb temperature of the room.
28

Sources in a production room: People (body warmth), Lighting systems,
Motor/equipment inefficiencies, Hot surfaces of machines or pipelines, Warm
products cooling down

Measurement: Expressed in kW (or W) and determined from temperature rise.

HVAC impact: Requires cooling capacity to maintain room temperature.
Data obtained from the MOHA soft drinks human resource department there are 4 operators
stationed in shifts per day. Since the production room is a path way to another department an
average of 50 peoples inter and leave the room per day including machine operators. This
information is obtained by interviewing the four machine operators of the room and from the
experience i sow while I stayed for workdays.
According to ASHRAE 62.1 standard 75 w of sensible heat is generated per person for
factory standard (75w/ person). So to calculate the total sensible heat multiplying the number
of peoples interring and leaving the room by 75w, it gives 3.75kw of sensible heat is found.
Latent Heat

Definition: Heat related to moisture in the air, caused by evaporation or
condensation—no temperature change in dry-bulb terms, but humidity changes[9].

Effect: Increases the humidity ratio (grams of water per kg of dry air) in the room.

Sources in a production room: Occupants (breathing and sweating),Open water
surfaces in processes, Steam leaks or poorly insulated steam lines, Ventilation
bringing in humid outdoor air, Infiltration (uncontrolled humid air from outdoors)

Measurement: Often expressed in kW or as mass of water vapour (kg/h).

HVAC impact: Requires dehumidification cooling coils must drop air temperature
below its dew point to remove moisture.
According to ASHRAE 62.1 standard 55w of latent heat is generated per person for factory
standard (55w/person). So to calculate the total sensible heat multiplying the number of
peoples interring and leaving the room by 55w, it gives 2.75kw of latent heat is found.
So total heat generated by occupants is calculated by
Qt=Ql+Qs , where Qt is latent heat and Qs is sensible heat
29
Qt=2.75+3.75 =6.5Kw
A total of 6.5 Kw heat is generated by the occupant inside the production room.
2. Additional Heat Due to lighting
Lighting systems convert almost all of their electrical energy into heat. In a production room,
this heat is 100% sensible (no moisture is added) and is released into the air or absorbed by
surrounding surfaces. Even ―cool‖ LED lighting produces heat. it’s just less than older
fluorescent or metal halide systems[11] .
LED light
Figure 13 LED light inside the CO2 gas production room
Lighting systems convert almost all of their electrical energy into heat. In a production room,
this heat is 100% sensible (no moisture is added) and is released into the air or absorbed by
surrounding surfaces. Even ―cool‖ LED lighting produces heat it’s just less than older
fluorescent or metal halide systems.
According to ASHRAE 62.1 standard an LED light for factory lighting power density for
factory production space is spaces 12w/m2. There are LED lights inside the production room
so the total lighting load will be 12w/m2.
Qlighting=A+qL where Qlighting is total lighting heat generated, A is area of production room ,
Qlighting is total lighting load
Qlighting=1537.2m2+ 12w/m2
30
18.4464kw
Totally 18.4kw of additional heat is generated due to the LED lights found inside the
production room.
3. Additional Heat Rejected from Machines
Inside the Co2 production room there are several machines used to converts soda ash in to
carbon dioxide gas. That can later be used in the PET and glass line soft drinks production. In
Ethiopia, MOHA often sources CO₂ as a by-product from nearby industrial plants (fertilizer
or breweries), then purifies and stores it for use in carbonation. On-site CO₂ recovery units
are also common, especially in bottling factories, to recycle CO₂ released during the filling
process.
In order to determine sensible heat generated from equipment’s inside the production, heat
evaporated from each machines must be known. A recorded heat generated from the
production machines and temperature change in every 4 hour is demonesterated in figure
below
Figure 14 a) Machine lay out b) Recorded heat generated by machines
A data collected from machine sensor heat generated by essential machines is recorded in the
following table.
31
Table 6 Essential machines and heat they emit to the atmosphere
Machine Type
Boiler
Scrubber 1
Scrubber 2
Scrubber 3
Condenser
Purifying unit
Released Heat to the atmosphere
250kw
30kw
32kw
34kw
133.5kw
54kw
In total of 533.5kw of sensible heat is produced and released by the machines towards the
production room environment.
4. Additional Heat by Ventilation
Ventilation is an essential requirement in HVAC system design to maintain indoor air quality
by diluting indoor contaminants and providing sufficient oxygen for occupants. However,
introducing outdoor air also adds a significant thermal load to the space. The additional heat
due to ventilation is calculated per person, based on the required outdoor air supply rate and
the difference in enthalpy between outdoor and indoor conditions[12].
 Ventilation Air Flow Requirement
It is the minimum outdoor air requirement is specified per person and per unit floor area. An
estimate 10L/s air flow is proposed According to ASHRAE Standard 62.1. The Co2
production room is estimated to experience an average 50 workers leaving and entering the
room, it typically will be 50x10 L/s = 500l/s total air flow by ventilation[12].
 Heat Load Due to Ventilation
The total heat gain from ventilation per person is given as:
Qvent=V˙oa×ρ×(Tout−Tin)
Where:

V˙oa= outdoor air volume flow rate per person (m³/person) (500l/s=0.5m3/sec)

ρ = air density (≈ 1.2 kg/m³)

(Tout−Tin)= outdoor and indoor temperature deference (340C-240c=100c)
This includes:
32
Qvent=0.5x1.2(34-24)
=6kw
A total of 6kw sensible additional heat is experienced by ventilation
 Latent Heat Load
According to ASHRA 62.1 standard the latent heat is taken as 45% of sensible heat.
So 5kwx45%= 2.25kw total additional latent heat is experienced.
2.8 Results
After obtaining the necessary heat generated within and outside the C02 gas production room
now development of AUTOCAD design. The total additional heat generated are listed in the
following table.
Source of heat
Heat load inside the production room
Additional heat due to occupants
Heat Due to lighting
Heat Rejected from Machines
Heat by Ventilation
Heat Load (Kw)
91.5kW
3.75kw of sensible heat
2.75kw of latent heat
18.4464kw
533.5kw
6kw Sensible heat load
2.25kw Latent Heat Load
Total Heat Load
658.194kw
33
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