Design and Construction of a Spin Dryer
Chapter One
THE PURPOSE OF CONSTRUCTION
This project is designed and constructed to achieve the following goals:
- To design and construct a spin dryer that will recycle brewery waste (spent grains).
- To design and construct a machine that can dry rapidly trough spinning.
- To design and construct a machine that will have high degree of automatization.
- To design and construct a machine that will take less drying time.
- To design a machine that will be easy in construction but have high efficiency.
- To design and construct a machine that will be cheap to operate and maintain.
- To design and construct a machine that will require less energy.
- To design and construct a machine that could impress on existing design taking into cognisance, areas of need.
CHAPTER TWO
LITERATURE REVIEW
HISTORY ABOUT SPENT GRAINS DRYING
Drying of spent grains through dryers stunted about six decades ago. Different dryer types were used to dry the spent grains after brewing. The various types are:-
Steam-tube dryer, Direct-fired dryer, Flash-type dryer, Steam disk dryer.
Steam-tube dryers were the first type used to dry brewer’s spent grains. Direct-fired rotary drum dryers then appeared in early 1940’s and bean to capture a significant portion of the market because of their high through put capabilities. High volume flash-type dryers, also direct-fried were developed for use in the grain products industry. Subsequently, an innovative type of steam dryer emerged which utilized rotating steam-heated discs for the drying process. Spent grains will be considered as having been screw pressed to a moisture content of 65% and are to be dried to 9%.
STEAM-TUBE DRYER
The old company that pioneered steam-tube dryers still has a number of well designed units in operation processing spent grains. For this example, the dryer model used has a drum 10ft in diameter by 70ft long. For an input rate of 20, 597 pounds per hours of 65% moisture of spent grains. The evaporation rate would be 12, 675 pounds per hour of water, producing a net of 7922 pounds per hour of dried grains at 9% moisture content. The steam required would be 1.54 pounds of steam to evaporate a pound of water.
DIRECT-FRIED DRYER:- The direct-fried dryer has earned a reputation in the field of drying spent brewer’s grains and has earned a reputation for effective performance. A dryer of this type was installed at the unilleas Brewing Company of Milwaukee. WI in 1941, since that time direct-fried dryers have been installed in major breweries throughout the world.
The direct-fried used for this example is a 3-pass unit, 10.5ft in diameter by 32ft long. Fried with natural gas or oil for an incoming load rate of 22,365 pounds per hour at 65% moisture contents. 1, 266pounds per hour of previously dried grains would be recycled and market to provide a feed rate into the dryer 23,630pounds per hour at 65% moisture content. The evaporation rate would be 13, 763 pounds per hour of water.
FLASH-TYPE DRYER:- The Chicago Company that manufactures drying equipment produces and excellent flash-type drying system. The dryer example for this study is one that will accept an input of 3600 pounds per hour at 65% moisture content.
After considering the various means through which the spent grains are dried, we discovered that they lack merits either in one way or the other. In our research, we discovered that spin dryer would have advantage over the presently used dryers in our breweries. Although spin dryer is used for drying clothes, we have adapted the technology and modify it to suit our purpose for drying of spent grains.
INTRODUCTION OF THE PROJECT-SPIN DRYER.
Spin dryer was invented in 1946 by Caesar Salad in the US.
What is a Spin Dryer?
During a spin cycle, the perforated spin tub or basket spins rapidly. The centripetal force generated by the spinning action extracts water from the clothes and forces it through the holes in the spin tub/basket. The faster the spin cycle, the more water is extracted.
CHAPTER THREE
DESIGN SOLUTION
There are different dryers that are alternative to spin dryer. The alternative dryers are not as sufficient in drying spent grains as the spin dryer. So in that view our spin dryer is design to solve inefficiency or problems faced by the alternative drying machines.
ALTERNATIVE DRYER AND THEIR DISADVANTAGES
- Electrical Dryers: These generally uses a coiled that is heated by using electric current. The amount of electric current is varied to adjust the air temperature. It is designed to dry fabric and could not be used in drying spent, beside, it is very expensive and require high technical competency to produce and operate.
- Gas Dryers: These empty a gas burner that burns natural gas. It is mostly found in oil fields and natural gas fields, as well as in smaller quantities-in coal beds. Since it is used in oil fields, it lacks merit in drying of spent grains.
CHAPTER FOUR
THEORY OF DESIGN AND ANALYSIS
THEORY OF DESIGN
The theory of design of spin dryer is based on the effect of a centrifugal force on the spent grains inside the basket. The spent grains are pushed towards the wall of the basket by centrifugal forces, which are compressed to the wall of the basket and the moisture content is removed as the basket is spinning.
A centrifugal force is a force which acts away from the centre of rotation. Centrifugal forces are commonly identified with the following effects such as when a passenger in a car is “thrown” to one side when a sharp turn is made, the passenger is in a rotating frame and thinks centrifugal force pushes him outward.
Centrifugal force arises due to the property of mass known as inertia (the reluctance of a body to change either its speed or direction).
CHAPTER FIVE
CONSTRUCTION/MAINTENANCE
PROCEDURE
MATERIAL SELECTION
In selecting the materials for the construction of a Spin Dryer, the following factors were considered:
- The availability of the materials.
- The suitability of the materials for the working conditions in service – the ability of the materials to meet the functional requirements as having reasonable tool life and durable .
- The cost of the materials were considered.
- The ability of materials to resist corrosion was considered.
CHAPTER SIX
COST ANALYSIS
MATERIAL COST ANALYS
CHAPTER SEVEN
DISCUSSION
RECOMMENDATION
Prior to the design and fabrication of this project, other available alternatives were considered but more proved to be effective and efficient as our spin dryer thus arriving at this model and specification.
The objective of this project was well achieved as the spin dryer was able to dry all the moisture content in the spent grains within a possible time-frame. The dryer was found to be effective, cheap in operation, cost of maintenance is low and affordable.
Having completed the fabrication, of the spin dryer and subsequent performance test carried out successful, the following recommendation were made:.
- That the dryer can used to dry spent through spinning.
- That the dryer can be used to dry clothes by spinning at an extremely rapid speed.
- That further research work on how to remove the grains from the basket quickly after drying be carried out.
- That the equipment cold be use as a reference to anyone embarking on similar project.
- That the department should conduct workshop and sensitization seminar to the public and students on the economic use of the machine.
- That since the equipment was effective and made from locally available materials, it is recommended that the industrial centre limited in IMT should liaise with the designer of the equipment to embark on mass production of this model after a little modification.
That, the machine should be use for exhibition as a form of enlightening the public on its numerous economic uses.
That the design of the spin dryer could be modified in future for greater efficiency. We recommend those who would work on this project to particularly tackle the problem of removing the dried spent grains from the basket.
CONCLUSION
This project has been satisfactorily completed and has met a recommendable high performance for the effective drying of spent grains within a limited time.
Having met this target of functionality, the immediate problems encountered was the scarcity of spent grains for the testing.
We encountered many problems during machining of parts as most of the machines in workshop are not functioning, some that function could hardly give the required precision as output.
The cost of materials were so high as this project was done at the period of price increment of fuel which affects every other commodities.
Nevertheless, we enjoyed the design and fabrication job which we did on the Spin Dryer. Especially since its performance is effective and reliable, therefore it has satisfied its desired purposes, hence it may be generally accepted to be efficient.
However, this project is welcome by so many quarters, as it shall project this country to a greater height of technological emancipation and also create job to the jobless. It shall in no mean word provide enough food to the poultry, which would finally be consumed by man.
Again, it is expected that at higher proficiency and mass production, the cost of production would be reduced.
BIBLIOGRAPHY
- Sharma. P.C (2003). Production Engineering Ram Nagar: Eurasia publishing house (RVT) Ltd.
- Khurmi, R. and Gupta, J. (2994). Machine Design Ram Nagar: Eurasia publishing house (RVT) Ltd.
