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Modification And Performance Evaluation Of A Cold Room Storage Structure
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3.5.4 Thermal Properties
Low thermal conductivity materials were was as thermal insulation of the cold room because the thermal insulation of a cold room is temperature dependent heat transfer occurs of a higher rate across materials of high thermal conductivity.
3.5.5 Food safety
Materials that can protect stored food retain the quality of the product and cold add no effect to the stored produce was chosen.
3.5.6 Availability of Materials
The chosen materials were selected on the basis of their local availability and affordability.
3.5.7 Gas Selection
Most widely used refrigeration’s are those which are a liquefiable vapour as refrigerants. Based on the operation of the refrigerator being a cyclic process, properties such as temperature (℃), pressure (bar) specific enthalpy (kj/kg), specific entropy (kg/kg.k), specific volume (m3/kg) were put into consideration. Dichlorodifluoro methane (R12) was selected based on the fact that it has mineral ozone depletion potential and is widely used in most commercial refrigeration’s.
3.6 Installation procedure and assemble
As a integral part of the cold storage system the following component was install for the effectiveness of the cold storage system which are temperature and relative humidity controller, time delays.
3.6.1 Application of the Installation
This standard operating procedure (SOP) describes the procedures required for the measurement of temperature and percentage relative humidity (%RH).
This procedure is applicable for measurement obtained in a zero to 15 degrees Celsius (℃) environment with a maximum relative humidity of 85%.
Temperature is measured using a semi-conductor sensor and percentage relative humidity using a polymer capacitive. Results are digitally displayed on the Arturo display (LCD) screen. The instrument can be operated with either a 9 – volt (v) battery or a 9-V alternative current (AC) adapter.
3.6.2 General Operation
F1 - Set temperature
F2 - Differential
F3 - Compressor delay
F4 - Calibration
Press and hold that s-button until you see F1 on the display, you then release the s-button and can use the up or down arrows to move from F1 through F4.
If you have F1 showing, hold the S-button and while holding it press the up or down arrows to pick the temperature you want it set at. Once you have the set temperature you want, release the S-button and press the power button once to save it. If you forget to press the power button when you are done, the STC-1000 won’t save your change.
F2 is the temperature differential, as I mentioned, same deal, press and hold the S-button until F1 shows up – release the S-button, and press the up or down arrow to get to F2: Once you are on F2, hold the S-button again and press the upon arrows to pick a differential. 0.5 or 1C is usually fine, but fine tune it to your system. If you have it seat 1.0, and the temperature of the liquid gets 1C over your set temperature, the cooling plug will kick in, the reverse is true for heating.
F3 is the time delay for engaging the cooling units, and is to preserve the compressor of your chest cold storage system.
F4 is temperature calibration. Always test your temperature probe with a known temperature, boiling water, freezing water, or something in between using another temperature probe you trust to compare. If its off, you can make adjustments.
When you test the STC-1000 don‘t freak out if your cooling outlet doesn’t power up right away. It will wait for the differential period before kicking on. If you are differential is set for 7 minutes, wait for 7 minutes before you go ripping wires out.
3.7 Working Principle of Cold Storage System
The compressor compresses vaporized refrigerant to high pressure and high temperature to raise the boiling point of refrigerant. The condenser then liquefies the vaporized refrigerant to high pressure and high temperature state thus heat rejection take place.
The condensate from the condenser is collected in reservoir and allow to pass through expansion value where its pressure and temperature decreases from earlier state The low pressure liquid refrigerant then passes through storage compartment and the heat of hot air in the storage age compartment start evaporating the liquid refrigerant hence heat in the storage compartment decreases and cooling is produced. Thus, heat content of fruits and vegetables decreases and it cools due to cylic process. The chived air is circulated to stored fruits and vegetables by the blower.
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ABSRACT - [ Total Page(s): 1 ]ABSTRACTÂ Â Â The cold storage structure was modified and evaluated for the storage of fruits and vegetables at the department of agricultural and bio-environment engineering of Kwara State polytechnic, Ilorin; the cold storage structure consists of the following components; compressor, evaporator, condenser, accumulator, dryer, etc. the variable factors are temperature and relative humidity. The cold storage structure was tested with the following fruits; watermelon, cucumber, tomatoes and app ... Continue reading---
APPENDIX A - [ Total Page(s): 4 ]APPENDIX B: RAW VALUES OBTAINED FROM PHYSIOLOGICAL WEIGHT LOSS4.2 Output Parameters Result ... Continue reading---
LIST OF TABLES - [ Total Page(s): 1 ]LIST OF TABLESTABLESDescription2.1 General problems of each fruits and vegetables group at each handling3.1 Bill of engineering measurement and evaluation ( BEME)4.1 Average weight and temperature of samples both in cold storage and ambient condition4.2 Average value of physiological weight loss of samples4.3 Data obtained from cold storage and ambient temperature against time ... Continue reading---
LIST OF FIGURES - [ Total Page(s): 1 ]LIST OF FIGURESFIGURES                        Description4.1 Effect of weight loss on daily time for okro4.2 Effect of weight loss on daily time for pear4.3 Effect of weight loss on daily time for water leaf4.4 Effect of weight loss on daily time for bell pepper4.5 Effect of temperature against time interval in the cold storage and under ambient condition   ... Continue reading---
TABLE OF CONTENTS - [ Total Page(s): 1 ]TABLE OF CONTENTSTitle Page                              Certification Dedication Acknowledgement Abstract Table of ContentCHAPTER ONE:   INTRODUCTION1.1    Background of the Study                        1.2    Problems Statement 1.3    Aims and objective of the project 1.4    Justification of the Project 1.5    The Scope of the Project Work CHAPTER TWO:   LITERATURE REVIEW2.1    ... Continue reading---
CHAPTER ONE - [ Total Page(s): 2 ]CHAPTER ONEINTRODUCTION1.1   Background of the Study Fruits and vegetables are of great nutritional value. They are important sources of vitamins and minerals thus, essential components of human diet. Consequent upon this, there had been increased trade or commerce activities surrounding these commodities. Vegetable production forms a substantial percentage about 25% of the major food crops cultivated in the tropics and so it is the source of livelihood for a considerable section of the pop ... Continue reading---
CHAPTER TWO - [ Total Page(s): 5 ]CHAPTER TWOLITERATURE REVIEW2.1   Development of Cold Room Structure for fruit and Vegetables   Refrigerant and cooling of perishable food product is an important and fascinating area of application of heat transfer and thermodynamic. Refrigerant slow down the chemical and biological processing in foods the accompanying deterioration and the loss of quality. Cooling is defined as decrease in temperature of a substance or medium below its temperature of its environment. (Abubakar 2006) re ... Continue reading---
CHAPTER FOUR - [ Total Page(s): 5 ]The result obtained from the effect of weight loss on daily time for bell Pepper, it was revealed that the rate weight loss under ambient condition is high the rate of weight loss in the cold storage structure is low.The result shows that the temperature in the cold storage decrease with time interval while the ambient temperature very with time interval depending to the atmospheric condition.Cooling rate:- this is determine by plot of temperature against time. ... Continue reading---
CHAPTER FIVE - [ Total Page(s): 1 ]CHAPTER FIVECONCLUSION AND RECOMMENDATION5.1    CONCLUSION   A cold storage system was modified for performance and the following conclusion were drawn;   The percentage weight loss (PWL) varied between 0 – 41.7% . Maximum weight loss was found in ambient condition where as minimum (0.06%) was found in the cold storage system. The percentage weight loss was found increased with increase in storage period for both cold storage system and ambient condition,   The minimum tem ... Continue reading---
REFRENCES - [ Total Page(s): 1 ]REFERENCESAbubakar(2006) Storage Crops Require low Temperature and Humidity (80 to 90) Adebayo, M. F. (2015). Modification and Performance Evaluation of a Cold Room Storage Structure. Unpublished HND project, Department of Agric Engineering, Kwara State Polytechnic, IlorinAdebisi et al,(2009) Evaporative Cooling for the Storage of Fruit and Vegetable.Adewumi (2013) Temperature Affecting Performance of Cold Storage System.Anon, A. (2000).Recommendation for Chilled of Perishable Produce Internatio ... Continue reading---
