CHEMICAL ENGINEERING TRANSACTIONS VOL. 56, 2017 A publication of The Italian Association of Chemical Engineering Online at www.aidic.it/cet Guest Editors: Jiří Jaromír Klemeš, Peng Yen Liew, Wai Shin Ho, Jeng Shiun Lim Copyright © 2017, AIDIC Servizi S.r.l., ISBN 978-88-95608-47-1; ISSN 2283-9216 Analysing Qualitative Data Systematically using Thematic Analysis for Deodoriser Troubleshooting in Palm Oil Refining Intan Suhairi Salleh a , Nur Syuhada’ Mohamad Ali a , Khairiyah Mohd-Yusof* ,b , Hishamuddin Jamaluddin c a Department of Chemical Engineering, Faculty of Chemical and Energy Engineering, Universiti Teknologi Malaysia, UTM Skudai, 81310 Johor Bahru, Malaysia b Centre for Engineering Education, Universiti Teknologi Malaysia, UTM Skudai, 81310 Johor Bahru c Faculty of Engineering and IT, Kolej Universiti Selatan, 81310 Skudai, Johor, Malaysia khairiyah@cheme.utm.my Troubleshooting the deodoriser in palm oil refining is challenging because of complex design of vacuum system. Not all the required information to develop a good troubleshooting system can be obtained from documents and the literature. A mistake in corrective action may cause failure in plant operation and final oil quality. Since experienced plant workers have in-depth knowledge on the specific equipment and process that they are in-charge of, systematic knowledge acquisition from them can be used to develop a fuzzy logic- based troubleshooting system. This system can help other less experienced staff in identifying root cause of deodoriser failure before taking any corrective action. The qualitative data obtained from interviewing the plant experts must be analysed systematically to ensure that the information obtained are trustworthy. Therefore, this study implemented thematic analysis to sort knowledge based on a theme of the root cause of deodoriser failure. The thematic analysis consists of 5 steps, which are data familiarisation, code generation, theme searching, reviewing and description. Fifteen plant workers (includes engineer, supervisor, technician and operators) were interviewed to develop themes. The useful information is captured from the interview session through code generation. Two senior managers verified the final themes, and the theme is further described based on the theoretical knowledge and process description. The final themes presented as thematic tree provide fault propagation, while troubleshooting table has information on root cause and its necessary action. The main themes presented the root cause of deodoriser failure based on critical location, i.e. ejector. The documented thematic analysis can assist inexperienced workers to learn the prior knowledge of deodoriser failure sources from troubleshooting table and thematic tree. 1. Introduction Failing to obtain knowledge from workers in the plant especially from the front liner to troubleshoot failures during the process contributes to wrong decision making, wasting cost and time consuming. The absence of operators’ experienced and knowledge of the experts’ not only lead to incorrect way to diagnose fault and unable to eliminate and isolate the causes, but it also led to incorrect action to troubleshoot the failures, which all of its led to the negative outcome to overall plant performance. Due to the realisation of the urgency to obtain and integrating the experienced and knowledge of plant workers, it is emphasised to have a systematic guideline for troubleshooting failures at the process by organising, coding and writing the data using systematic approached call thematic analysis. Thematic analysis is an established method of organising qualitative data and has good potential in capturing knowledge and experienced of workers and experts. Boyatzis (1998) described thematic analysis is a method to identify, analyse and report patterns (themes) within the data. Thematic analysis has given advantageous in educational, early childhood and safety field. In educational field, results from thematic analysis can helps the lecturers to improve their teaching techniques by identifying knowledge obtained by the students in Problem Based Learning (PBL) class (Mohd-Yusof et al., 2014). The students’ knowledge has been discovered by DOI: 10.3303/CET1756220 Please cite this article as: Salleh I.S., Ali N.S.M., Yusof K.M., Jamaluddin H., 2017, Analyzsing qualitative data systematically using thematic analysis for deodorizer troubleshooting in palm oil refining, Chemical Engineering Transactions, 56, 1315-1320 DOI:10.3303/CET1756220 1315