DESIGN AND FABRICATION OF A CORN SHELLING MACHINE

Description

Chapter one

1.0                                                            Introduction

1.1                                                    Background of study

Corn is the most important cereal grain in the world, after wheat and rice, providing nutrients for humans and animals and serving as a basic raw material for the production of starch, oil and protein, alcoholic beverages, food sweeteners and, more recently, fuel. It is because of the important place of maize that it’s handling, processing and preservation within the optimum conditions must be analyzed.

In Nigeria, Corn is emerging as the third most important crop after rice and wheat, and it has significance as a source of a large number of industrial products besides its use as human food and animal feed Corn is also a versatile crop, allowing it to grow across a range of agro-ecological zones. Corn also is one of the agricultural semi-finished goods. Every part of Corn has economic value as the grain, leaves, main crop stalk, tassel and cob can all be used to produce a large variety of food and non-food products. After harvesting with sickle and plucking of cob manually, dehusking of cob is done by hand to remove its outer sheath and further grain is obtained by shelling the cob traditionally, i.e. by beating the dehusked cobs with sticks or with fingers or sickle, etc. In Nigeria this activity is mostly done by female farmers.

Corn is considered to be one of the most important staple crops in the world.  People in some parts of the world actually consider corn as their survival food. According to Adewale et al (2020), corn accounts for 43% of the Latin American diet. Because of the high need of corn grains, it leads to the invention of a wonderful tool called the corn sheller which helps in shelling the kernels from the cob as well as makes shelling faster and easier.

According to Adegbulugbe,  the problem of poverty, hunger and malnutrition would be alleviated if there is adequate production of corn, Corn also called maize plays an important dietary role in most parts of Africa, It is grown virtually everywhere, in tropical, subtropical and temperate regions where rain and irrigation is adequate (Adegbulugbe, 2018).

The major steps involved in the processing of corn are harvesting, drying, de-husking, shelling, storing, and milling. All these processes are costly and for the rural farmers to maximize profits on their produce, appropriate technology that suites their needs must be used. Corn processing not only prolongs its useful life but also increases the net profit farmers (users) make from mechanization technologies (Adesuyi, 2020). It is in this line that one of the most important processing operations done to bring out the quality of corn is shelling. It is basically the removal of the corn kernels from the cob. This separation, done by hand or machine, is obtained by shelling through friction or by shaking the products; the difficulty of the process depends on the varieties grown, and on the moisture content as well as the degree of maturity of grain.

Today, corn shellers come in wide variety of sizes and types. From the simplest hand-held device to the more complex bigger self-feeding machines powered by steam, corn kernel separation has been successful since then.

1.2 Statement of the Problem

The importance of maize in Nigeria has been on increasing side since early 1990’s as it is strongly supplements the traditional diet crops and is widely used in large communities such as schools, hospitals and prisons. The crop is grown mainly by smallholder farmers targeting both local and foreign markets. According to FAO (2014) agricultural production records, there had been a steady increase in maize production from 759,000 metric tons in 1995 to 1,200,000 metric tons in 2003. According to researchers, lack of appropriate corn shellers as one of the major constraints affecting commercial maize production in Nigeria. Traditional, Farmers shell the bulk of the maize using the method of beating on the bare ground or loosely packed in sacks. The method has low productivity, causes high physical damage and contamination with foreign matter resulting in low market value and reduced shelf-life of the crop. Other methods such as hand priming, shelling using manual corn shellers are not productive for commercial farming.

Many corn sheller have been fabricated in the past which did not fully meet the market requirements of commercial farmers due to its challenges such as high fuel consumption, low shelling efficiency and  high percentage of damaged grain (Smith et al., 2014). This study is therefore carried out to improve the model of the corn sheller to   meet the market requirements of the commercial maize farmers, agro-processors and maize grain traders.

1.3 Aim and objective

The aim of this work is to design an improved corn shelling machine that operates with high efficiency and flexibility

The specific objectives of the research work are to;

1. Design a portable corn shelling machine that will operate with minimum noise.
2. Construct a portable corn shelling machine that can effectively separate the corn from the cob.

• To improve the standards of living of people living in villages of developing countries.

1. To save time and cost, with high degree of production volume.
2. To design and construct a corn sheller that would not have much breaking effect of grains, leaving the cobs intact during the process.
3. To design and construct a corn sheller that is economic and have little or no complication in maintenance

1.4 Justification/ benefits of the study

The machine shells maize and automatically separate the used cobs and chaff from the grain. They deliver clean grain, used cobs and chaff through different outlets. This enables the farmer to obtain clean grain and used cobs for other uses at the same time and without additional labour.

This machine is inexpensive, small scale, and does not need outside help to build. The materials and tools are readily available and do not require communication with external parties to be built

The machine requires no foreign assistance at all. It can be built using local materials by the local craftsmen. There is no need for builders to communicate and interact with foreign parties.

1.5 conclusion

At the end of this work the complete corn sheller shall be fabricated with the expected average feed rate of the designed machine to be 2.06 kg/min. This implies a value of 123.6 kg/hr while average threshing efficiency as 1.65 kg/min (99 kg/hr). The average threshing efficiency to be 78.93 % while the average separation efficiency was 56.06 %. These values were an improvement on the values obtained for human labour (as reported by Adewumi et al, 2014) where human mechanical efficiency was determined to be 45% at the biomaterial test weight of 20 kg with actually shelled grain weight of 15.8 kg. They also reported that human throughput capacity was 26.67 kg/hr and actual grain handling capacity of 21.1 kg/hr at a shelling time of 45 minutes or 0.75 hr. this shows clearly that the designed machine would perform satisfactorily and can process about 1 tonne of maize in 9 hrs. The design can be modified in order to find ways to improve the separation efficiency of the machine.

1.6  Reference

Adegbulugbe, T.A. (2018). Design and Construction of a maize Sheller: Proceedings of the 5th annual conference, Nigerian Institute of Agricultural Engineers. Pg. 60

Adesuyi, J. (2020) Design and Construction of a Maize Thresher: An unpublished Ph.D Thesis, University of Ibadan, Nigeria.

Adewale, A.T., Adelowo, A.P and Solagbade, F.O. (2022) Design of a Corn Sheller.

FAO, 2014. FAO Statistical Citation Data 2004. URL. faostat.fao.org Copy right 2014

Smith D. W., Sims, B. G. and O’Neill, D. H., 2014. Testing and Evaluation of Agricultural Machinery and Equipment. Principles and Practice. FAO Agricultural Service Bulletin 110.

Adewumi, T. (2014) Performance Evaluation of a Locally Developed Maize Sheller with Husking and Winnowing Capabilities: Proceedings of the Annual Conference of Nigerian Institution of Agricultural Engineers held in Ilorin held in November, Vol. 26. Pg 68.