Available for download. CSA Global, Principal Geologist and Consultant, Dr Andrew Scogings presented on the “Drilling Grade Barite Density: Le Chatelier vs Pycnometer” at the recent Oilfield Minerals and Markets Forum Houston in May of 2018.
The presentation compares the Le Chatelier flask (liquid displacement) and gas pycnometer methods of determining the density of barite powder – the aim being to assess the gas pycnometer as a possible alternative to the current standard liquid displacement method.
Barite is naturally-occurring barium sulphate (BaSO4) used primarily as a weighting agent in drilling muds. Pure barite has a density of 4.5 t/m3, but naturally occurring barite often contains impurities such as quartz (silica; density 2.65) which reduce barite product density. The historically accepted grade was 4.2 t/m3, but the American Petroleum Institute (API) introduced an extra 4.1 grade in 2010.
The API specifies that barite product density is tested using the Le Chatelier method; this entails addition of approximately 80g of barite powder to kerosene in a glass flask and measuring the displaced volume. Although the equipment is relatively inexpensive, the Le Chatelier flask is a time-consuming method, is completely manual and takes several hours to complete.
Gas pycnometers may use various gases to determine the sample volume; results will be presented for argon and nitrogen gas pycnometers. Although gas pycnometers are relatively expensive compared with Le Chatelier flasks, pycnometers offer the benefit of quick turnaround (several minutes), automation and computer control, all of which are beneficial for statistical process control in a production environment.
ABOUT OUR PRESENTER
Dr Andrew Scogings
PhD (Geology), MAIG, MAusIMM, RPGeo (Industrial Minerals)
Dr Scogings is a geologist with more than 25 years’ experience in industrial minerals exploration, product development and sales management. Andrew has published papers on reporting requirements of the JORC Code 2012, with specific reference to Table 1 and Clauses 18 and 19 (industrial mineral Exploration Results) and Clause 49 (industrial mineral specifications). He has published numerous articles on industrial minerals in Industrial Minerals Magazine, SEG Mining News, AIG News and AIG Journal amongst others; addressing aspects of QA/QC, bulk density methods and petrography for industrial minerals exploration. He was recently senior author of two significant reviews: Natural Graphite Report – strategic outlook to 2020 and Drilling grade barite – Supply, Demand & Markets published in 2015 by Industrial Minerals Research (UK). He has co-authored several papers on lithium pegmatites including: Reporting Exploration Results and Mineral Resources for lithium mineralised pegmatites published during 2016 in the AIG Journal. Andrew is a Registered Professional Geoscientist (RP Geo. Industrial Minerals) with the Australian Institute of Geoscientists.