Development of a Multipurpose Solar Dryer

In many parts of the world there is a growing awareness that renewable energy has an important role to play in extending technology to the farmers in developing countries to increase their productivity. Solar thermal technology is rapidly gaining acceptance as an energy saving technology in agriculture application. This article presents the design, construction and performance evaluation of a solar dryer for food preservation. In the dryer, heated air from a separate solar collector is passed through beds of grains. The design of the dryer makes provision for the attachment of additional mirrors on two opposite sides of the solar collection chamber. Overall, the dryer is of simple design, cost effective, and made from affordable available materials and require little or no skills for its fabrication and operation. The results obtained fromtests carried out on the dryer revealed that the temperatures inside the drying chamber and the solar collector were highest when the side mirrors were at 45o to the vertical, giving optimum performance under various experimental conditions

The Effect of Beneficiation on Some Properties of Osun State Ceramic Raw Materials

Clay, feldspar and silica sand are important industrial minerals which often need treatment commonly known as beneficiation to improve the quality of ceramic tiles produced from these materials. The different minerals, after sorting, were treated separately in distilled water, alcohol and hydrochloric acid before being crushed in a ball mill; they were then characterized using a pelletron accelerator. The results show an increased silicon content for clay, silica sand and feldspar; and reduced aluminum content for clay and silica sand but not for feldspar. Iron impurity and its oxide are also shown to reduce by over 50% in all the minerals while potassium was found to be the dominant element in feldspar among the defining elements. In conclusion, the increased quartz in the mineral will improve the hardness, density, porosity, and rigidity of ceramic tiles as well as providing support and controlling shrinkage. Furthermore, increasing the mineral quotient in feldspar will enhance its fluxing potential

Bread-slicing machine

This study developed a compact front loading machine for slicing loaves of bread.  The machine is fast, efficient, safe and easy to operate.  It was designed to accommodate a normal loaf of bread per pass.  It works on the principle of gravity loaf in-feed system and the up-and-down reciprocating motion of the blade frame that carries 22 parallel cutting blades spaced at a regular interval of 14.5 mm apart.  It is driven by a 2 horsepower electric motor via a V-belt power transmission system.  The moving components are born on self-lubricating bearings and specially designed vibration absorbers; it automatically stops to save running cost once the loaf is completely sliced.  It also incorporates a crumb collection tray to enhance the hygiene of the process. Evaluation tests revealed that increasing the cutting speed above the standard commercial bakery speed of 420 r/min increased bread wastage and reduced uniformity of slice thickness

AN ASSESSMENT OF THE DISPLACEMENT OF A CAM FOLLOWER USING REGULA FALSI METHOD

Cam is a mechanical component that transforms circular motion to reciprocating motion by using mating component, called the follower. The principal aim of this work was to study and analyse the displacement of a cam-follower with Regula Falsi method and verify its input by using MATLAB and FORTRAN simulations. A study was conducted on angle of rotation and the displacement of the follower, which is equal to the radius of the cam given as transcendental equation to find the exact solution. The parameters such as initial guess, final guess, iteration counter and the desired displacement are involved in finding the angular displacement to the cam system in high speed rotation. The analysis was done using a computer programming that enables verification of the results obtained and ascertaining whether the inputs are correct or not for the displacement in cam follower system. The computer output showed results of the two data sets that yielded solutions and two that did not. The results revealed that the programme could be used to find the angular displacement corresponding to a given follower displacement for any cam; if the function CAMF is modified to include the appropriate radius function, r(x). The results further revealed that at a halve cycle of a rotating cam, which is equivalent to (x = 3.142 rad), is a solution that would provide the desired displacement of the follower (opening and closing of valves)