IPTEK The Journal of Technology and Science, 31(1), 2020 (e/pISSN:2088-2033, 0853-4098) DOI: 10.12962/j20882033.v31i1.5548 ORIGINAL RESEARCH IMPLEMENTATION OF A MATHEMATICAL MODELLING OF A ROTARY CEMENT KILNS Serlya Aldina | Juwari Purwo Sutikno* | Renanto Handogo Dept. of Chemical Engineering, Institut Teknologi Sepuluh Nopember, Surabaya, Indonesia Correspondence *Juwari Purwo Sutikno, Dept. of Chemical Engineering, Institut Teknologi Sepuluh Nopember, Surabaya, Indonesia. Email: juwari@chem-eng.its.ac.id Present Address Gedung Teknik Kimia, Kampus ITS, Sukolilo, Surabaya 60111, Indonesia Abstract Rotary cement kiln is the main equipment in the cement industry that has com- plex dynamic behavior, where any changes will affect the quality of the product and the consumed energy. A one-dimensional model of rotary kiln is needed to understand kiln’s behavior and improve kiln operating and design to achieve the optimum condition of product quality and energy required. In this study, the one- dimensional mathematical model of a dry rotary cement kiln with pulverized coal combustion is developed. This model consists of a set of nonlinear ordinary differ- ential equations and nonlinear algebraic equations that describe material and energy balance equations. The model has been solved numerically by using Matlab R2015a, and it has been validated by comparing the result with published experimental data. Based on the result, the steady-state simulation shows that the behavior of the model developed is appropriate with the results presented in the literature. It can be con- cluded that the model is accurate (error < 6%) to describe the profile of temperature and bed composition along with the kiln. It can be used to obtain a better under- standing of kiln’s behavior and improve the kiln operating and design to achieve the optimum condition. KEYWORDS: Calcination, Clinker, One-Dimensional Model, Pulverized Coal, Rotary Cement Kiln 1 INTRODUCTION Rotary kilns are commonly unit that used in chemical, metallurgical, and pharmaceutical process industries. Rotary kilns are used for heating, reacting, drying processes of solid material. In many cases, it can be used to combine those processes, such as the uses of rotary kiln in the cement industry [1] . Rotary cement kiln is the main equipment in the cement industry that can be used to produce a clinker from raw material through a complex reaction within the kiln by using a high-temperature condition. Process along the kiln consists of complex reaction and heat transfer between inside wall, freeboard gas, and solid material.