Article

# Mathematical Modelling of Pressure Distribution along the Die of a Biomass Briquetting Machine

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## Abstract

The screw extruder briquetting die is critical to determining the quality of biomass briquettes. In this study, mathematical models were developed to study pressure distribution along the briquetting die using the hot extrusion scheme and assuming a plug flow. Parametric analysis to determine the effects of design variables on die pressure distribution was carried out by simulation using developed mathematical models. Results showed that pressure along the die entry decreases rapidly with high yield strength of compacted biomass and with increased friction coefficient at the briquetting die interface. As friction coefficient at the die interface increases, there is rapid decrease in pressure along the length of the die. Parameters resulting in rapid pressure decrease along the briquetting die length would result in increased die pressure at the end of the screw extruder. The developed mathematical models and the results obtained could significantly contribute to design of briquetting dies.

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... High-pressure technologies utilize equipment, such as the screw press/extruder briquetting machine, mechanical piston presses, hydraulic piston presses, roller presses and pelleting machines [27]. Theoretical studies [28][29][30][31][32][33][34] have been carried out on some high-pressure densification technologies to understand the effect of design parameters on the operational performance of equipment. Similarly, empirical investigations have been carried out on some densification technologies using different biomass materials. ...
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... Several works have been done to research into biomass briquetting in Nigeria. Recent works, which investigated various aspects of biomass densification and technologies involved, include Jekayinfa et al. [132], Ojolo et al. [252], Orisaleye et al. [133,134,[253][254][255], Orisaleye and Ojolo [256,257], Ojomo et al. [258], Dairo et al. [259], and Adeleke et al. [260]. Abdulkareem et al. [261] investigated the combustion characteristics of biomass briquettes while Umar et al. [262] investigated the application of briquettes to fish processing. ...
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India is an agrarian country with the abundant availability of biomass. Therefore, it is essential to make the best use of the biomass potential. It is indispensable to effectively use this resource so that the problem of energy could be eased. In order to accomplish this objective, an effective and efficient utilization of the biomass is the key. Biomass is the only source of energy that stores carbon into its structure and releases back into the environment upon the use. Uses of biomass for different application results into various operational, environmental, financial and even logistic issues. The aim of this chapter is to make the reader aware of the liberal spectrum of biomass available in general and India in particular. This chapter also presents the utilization of biomass under different technology pathways for various applications and operational issues are discussed. The data is helpful to arrive at the correct technology alternate for the use of a given biomass type.
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