Risk assessment of Gördes nickel-cobalt process plant

Download
2019
Torun Bilgiç, Elif
High pressure acid leach (HPAL) is commonly utilized hydrometallurgical process for low grade laterites for the extraction of nickel and cobalt. The plant malfunctions bring about catastrophic accidents that prove the irreversible effects on human life, society, environment and economy. Identification of hazards is one of most important study for the risk assessment. Thus, investigating and reducing the probability of hazards and risks and inhibition of such accidents is very crucial for community and firms. In this study, the risk assessment of the Gördes Nickel–Cobalt process plant was performed. The plant is a huge construction and has complex working mechanism intrinsically can result in serious work accidents. This study was aimed at investigating the possible hazards and risks to construct risk assessment to contribute to develop risk assessment plans and risk management strategies for the plant operations and mine site. Firstly, system’s working principle was searched. Determination of possible hazards at units, estimation probability and severity of results caused by hazards and decision making of acceptable risk levels, elimination of risk or planning actions for decreasing the risk in terms of suitable safeguards and recommendations based on engineering judgement and previous data was done. In addition, accident data of five years (2014-2018) was investigated in order to determine the critical nodes of process plant, jobs, working hours etc. As a result of the present study, the most risky area is HPAL that employees had accident mostly at HPAL area by 10.65 percent due to the unacceptable level of risk inherent in its operation. Unacceptable level of risk in the process plant can be decreased by level, flow, pressure, temperature monitoring, control valve, secondary containment, interlock system, spare pump, level alarm etc. Accident statistics shows that the almost all accidents can be prevented by proper training, development of safety culture and administrative arrangement. This study can contribute to the integration of the occupational health and safety management system with quality, environmental, financial management systems, and sustainability of the whole system. This process plant has been unique for Turkey, thereby risk assessment’s analysis may be a reference for similar plants to be constructed in future. In addition, accident analysis of the process plant can help to focus on risky working areas and conditions, thus the accident prevention techniques and appropriate trainings can be developed in terms of the results of the analyses.

Suggestions

Nickel extraction from Gördes laterites by hydrochloric acid leaching
Göveli, Ahmet; Atalay, M Ümit; Department of Mining Engineering (2006)
Leaching is the most widely used process for extraction of nickel metal from lateritic ores. In this study, nickel extraction from Manisa-Gördes region laterites by hydrochloric acid leaching is aimed. The mineralogical analysis of sample showed that hematite, goethite, dolomite, quartz and smectite are the main minerals in the ore. Attrition scrubbing, cycloning and magnetic separation with permroll were used as preconcentration processes but results were unsatisfactory. HCl leaching experiments were condu...
Pressure leaching of Çaldağ lateritic nickel ore
Önal, Mehmet Ali Recai; Topkaya, Yavuz Ali; Department of Metallurgical and Materials Engineering (2013)
The purpose of this study was to investigate the process optimization of combined high pressure acid leaching (HPAL) and mixed hydroxide precipitation (MHP) route for the extraction of nickel and cobalt from Çaldağ lateritic nickel ore. In order to extract nickel and cobalt values into pregnant leach solution (PLS), several process parameters of HPAL including acid load, temperature, leaching duration and particle size were investigated in comparative manner at constant solid concentration and agitation spe...
Extraction of nickel and cobalt from lateritic ores by nitric acid /
Saka, Onur; Topkaya, Yavuz Ali; Department of Metallurgical and Materials Engineering (2014)
This thesis study is related to the extraction kinetics of nickel and cobalt from lateritic nickel ores from Gördes/Manisa region of Turkey. The experimental studies involved the optimization of nitric acid leaching of nickel laterite ores at atmospheric pressure for high nickel and cobalt extraction. The main parameters optimized after the characterization of laterites were the nitric acid concentration, leaching temperature, duration of leaching and the particle size of the ore sample. The atmospheric lea...
Pressure leaching of Sivrihisar-Yunus Emre nickel laterites
Seçen, Berk; Topkaya, Yavuz Ali; Department of Metallurgical and Materials Engineering (2011)
The aim of this thesis study was to extract nickel and cobalt from Sivrihisar limonitic nickel laterite ore by high pressure acid leaching (HPAL) method under most economical operating parameters. Optimizing the conditions to yield a saleable quality mixed hydroxide product from the pregnant leach solution (PLS) was also investigated. To extract high amounts of nickel and cobalt from the laterite matrix; leaching duration, leaching temperature and sulfuric acid/ore ratio were studied at fixed conditions of ...
Comparative study of high pressure and atmospheric acid leaching for the extraction of nickel and cobalt from refractory nickel laterite ores
Korkmaz, Kıvanç; Topkaya, Yavuz Ali; Department of Metallurgical and Materials Engineering (2014)
In this MSc thesis, the refractory minerals that may be present in limonitic nickel laterite ores will be tried to be leached under the optimum conditions of high pressure and atmospheric acid leaching. The results of the different methods of leaching to be obtained will be compared in terms of the Ni and Co extractions.
Citation Formats
E. Torun Bilgiç, “Risk assessment of Gördes nickel-cobalt process plant,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Mining Engineering., Middle East Technical University, 2019.