Design And Fabrication Of 240kg Ice Block Making Machine

ABSTRACT

This project work presents the design and fabrication of 240kg ice block making machine. In present day hotels, shops, resort and bar require more ice block in a very less time. So, to solve this problem and control the required time for ice formation, we constructed an ice block making machine that produces ice block within the period of 8(eight) hours. In present days, in market this machine is available with very high cost. So we constructed it locally to make it at optimum price. Ice making machine consists of four key components; the evaporator, the condenser, the compressor and the throttle/expansion device. The compressor is to compress low pressure refrigerant vapor into high pressure vapuor and deliver it to the condenser. The high pressure vapor is condensed into high pressure liquid and drained out through the throttle/expansion device to become low pressure liquid. At this instant the liquid is conducted to the evaporator where heat exchanging occurs and ice is created, at this point there is a change of state from liquid to vapuor and returns back to the compressor. This is one complete refrigeration cycle. Ice making machine works on an ideal vapor compression cycle. The conventional ice plant has been studied and a prototype model of an ice plant has been fabricated with above said accessories and the fabrication techniques and methods used are; riveting, brazing, cutting, drilling, mechanical fastening and welding.

CHAPTER ONE

INTRODUCTION

Ice is water in its solid state. This occurs when liquid water is cooled below 0°c (273K, 32°F) at atmospheric standard pressure. Since ancient times, ice has been used as a means of processing, cooling, preserving and storing of food and drinks. Ice is available naturally in some parts of the globe, although not all year round but is needed all year round. For this reason ice is now produced industrially by means of mechanical refrigeration.

An ice making machine also referred to as an ice maker, ice generator is a machine that produces ice in the shortest period of time. This machine operates on the principle of refrigeration and it produces ice to meet the need of the people which includes; food storage or preservation, processing, chemical Ice is used in a variety of ways including sports, winter sports, cooling, and ice sculpture.

Ice is a crystalline inorganic solid with an ordered structure and hence ice fits the properties of minerals. It possesses a regular crystalline structure based on the molecule of water which consists of a single oxygen atom covalently bonded with two hydrogen atoms or H-O-H. Ice has an unusual property when frozen at atmospheric pressure in the sense that it is approximately 8.3% less dense than liquid water.

Some fundamentals of refrigeration system to aid this research:

A). Heat is a form of energy transferred by virtue of a difference in temperature. Heat exists everywhere to a greater or lesser degree. As a form of energy it can neither be created nor be destroyed, although other forms of energy may be converted into heat, and vice versa. It is important to remember that heat energy travels in only one direction; from a warmer to a cooler object, substance, or area.

B). Cold is a relative term referring to the lack of heat in an object, substance, or area. Another definition describes it as the absence of heat, no process yet has been devised of achieving “absolute zero,” the state in which all heat has been removed from any object, substance, or area. Theoretically this zero point would be 459.69 degrees below zero on the Fahrenheit thermometer scale, or 273.16 degrees below zero on the Celsius thermometer scale.

C). Refrigeration, or cooling process, is the removal of unwanted heat from a selected object, substance, or space and its transfer to another object, substance, or space. Removal of heat lowers the temperature and may be accomplished by use of ice, snow, chilled water or mechanical refrigeration.

D). Mechanical refrigeration, is the utilization of mechanical components arranged in a “refrigeration system“ for the purpose of transferring heat.

E). Refrigerants, are chemical compounds that are alternately compressed and condensed into a liquid and then permitted to expand into a vapor or gas as they are pumped through the mechanical refrigeration system to cycle.

• Background of the Study.

Food by its nature begins to spoil the moment it is harvested and for this purpose, in ancient times, in order to survive man had to come up with means of preserving the food and for this purpose man had to harness nature in order not to consume spoilt food. Freezing was an obvious preservative method to the appropriate climate and geographical areas that have freezing temperatures for even parts of a year made use of the temperature to preserve foods, less than freezing temperatures. Ice was used to prolong storage times, thus ice cellars, caves and cool streams were developed and put to good use, for that purpose wealthy families in Europe, Asia, America had ice cellars or ice houses built to store ice and food on ice, cellars for wine, soon the icehouse became an icebox and because of this the idea of refrigeration came to be. Until the 1800’s when mechanical and thermal refrigeration was introduced ice was mostly used. Therefore ice can be said to be the principal means of refrigeration until the 20^th century and it is still in practice in most countries across the globe.

It has been proven that refrigeration of food at an optimum temperature plays a fundamental role in maintaining food safety. In many cases it is necessary to control and maintain the storage temperature, which will be different for each type of product.

In addition, if we lower the storage temperature of perishable foods, we will be able to significantly reduce the reproduction speed of the vast majority of microorganisms. These are the cause of decomposition, favouring the loss of product quality and generating possible illnesses in consumers.

Refrigeration slows down the metabolism of organic matter to a near standstill at -18°C (the international standard for most frozen products). At this temperature, the partial or total inhibition of altering processes in food, such as certain enzymatic reactions or the metabolic degradation of proteins, is achieved. This slows down the decomposition and spoilage of these foods, as well as preventing possible health problems after consumption.

 Statement of the problem.

Africa is known for its tropical climate which implies that we are likely to get dehydrated as we move around daily. With so much thirst comes the desire for cold beverages, this is one of the reasons why we need ice block. Another major reason is the poor power supply in must African countries especially in Nigeria. As a result, we need ice block to preserve foods and ingredients.

Ice is produced mechanically on an industrial scale for uses; in food storage, chemical manufacturing, medical usage, curing (first aid), drug storage, etc. Most commercial ice producers or icemakers produces ice in different fragmentary ice which includes; flake ice, tubular, cubes, crushed, using a variety of techniques. This is as a result of ice having a variety of application and high rate of demand. Large ice plants can produce up to 65 tons of ice per day. Small scale ice produces cannot match this since they mostly make use of home refrigerators and due to financial constraints, shortage of power supply.

In Africa and Nigeria in particular where there is poor power supply to operate refrigerator all day round, ice block become the best alternative to refrigerate our foods and consumables hence the purpose of the design and fabrication of ice block making machine.

This project work however does not solve the problem posed or associated with power shortage or financial constraints being faced by small scale icemakers. But however, this project work on design and construction of 240kg ice block making machine is intended to increase the volume of  production per day by reducing the harvest time for production of  ice, instead of a whole day (24hrs), this work is intended to produce ice within 8 hours and 3 batches of production a day.

• Aim and objectives of the study.

The aim of this project work is: To design and fabricate7 240kg ice block making machine.

And to determine the aim the following objectives will be considered which includes;

1. To increase productivity as well as to reduce the cost of production
2. To produce ice block within 8 hours and 3 batches of production a day.

• Significance of the study

The design and fabrication of 240kg ice block making machine would lead to a decrease in the harvest time of ice blocks, it will lead to a significant increase in the volume of ice blocks produced per day.

This project work will be beneficial to these sectors;

1. Provision stores/Restaurant: ice is used to cool drinks and beverages. As it melts it absorbs heat and keeps the drink near 0°C. It is also used as preservative for most fruits, vegetables, fish, margarine, beef, eggs and other frozen foods such as; chicken parts or full, turkey, meats and gizzards etc.
2. Roadside traders and hookers to chill their bottle/sachet water and beverages in other to make more sells.
3. Sports: In sports ice is used as part of first aid treatment to injured athletes to stop bleeding, reduce swelling. Reduce the effect of muscle pull and other muscle injuries.
4. Homes: Domestically, ice is used to preserve, and store edibles.
   

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   Pages:  66

   Category: Project

   Format:  Word & PDF               

   Chapters: 1-5                                          

   Source: Imsuinfo

   Material contains Table of Content, Abstract and References.