Ausenco Limited is a multinational engineering, procurement, construction management, and operations service provider to the energy and resources sectors. Its head office is in Brisbane, Australia. The company name is an amalgamation of "Australian Engineering Company".
A geometallurgy study aims to link metallurgy and geology to reduce technical risk and enhance the economic performance of a mineral-processing plant. It does so by accounting for variability in a deposit to develop cash flow models with variable throughput rates. High-quality sample selection for metallurgical test work that are representative of the deposit is an essential component of a geometallurgy study, but the large multi-dimensional dataset makes sample selection a daunting task, as classifying the dataset while respecting its heterogeneity is difficult. This paper presents a streamlined approach for sample selection, utilizing statistical analysis techniques in Python. It cuts down time to select samples from around 1200 s per drillhole to about 60 s per drillhole for data classification and from 12 h to 8 h for handpicking samples from the classified dataset, translating to cost savings. The cumulative sum method and k-means clustering method are used in the methodology to elegantly classify the data and select representative samples. The effectiveness of the methodology is demonstrated by presenting data from a pre-feasibility study of a copper-iron mine in which 40 samples were selected for flotation test work.
Machine learning is used in air quality research to identify complex relations between pollutant levels, emission sources, and meteorological variables.
The mining industry needs a low-cost and reliable breakage characterization test which can rapidly process a large number of samples for geometallurgical modelling. The more samples are tested, the better is the understanding of the ore hardness variability and lower the design or production risks. The proposed solution is a new testing device, herein named Geopyo center dot ra center dot, which is a variation of a roll crusher with an adjustable gap and instrumentation to measure breakage forces and energy applied to rock particles during the breakage process. The principle utilises a controlled degree of crushing, with absorbed breakage energy being a response rather than an input. The new testing device is capable of rapidly testing rocks over a wide range of sizes and accurately measured energy levels. For a range of ores, the results were demonstrated to provide outputs that replicate the breakage modelling from full JK drop Weight tests. In addition to being suited to testing drill cores and small sample masses, the Geopyo center dot ra center dot provides a distribution of particle strengths within every sample. This paper provides an introduction to the concept, development of the prototype device and breakage calibration results that indicate its potential to become a major player in geometallurgical ore testing.
Abstract The thickened width of floating ice roads has tended to be a practical consideration rather than a design aspect. Standard methods of calculating the required thickness of ice roads consider the road to be of infinite length and width. In this paper we outline calculations of the bending stress for a finite width ice road. The recommended minimum width that should be thickened to the design value is given below where Lc is the ice characteristic length: Longitudinal wet cracks reduce the load bearing capacity of an ice road. Stress analysis indicated that as long as the ice is less than 1.83m thick and the footprint of the vehicle is longer than 10 m (33 ft) then a safe and simple to use estimate of the road capacity for a vehicle travelling parallel and adjacent to the crack is given by:
Fastening optical elements with adhesives presents challenges when dissimilar materials (almost always the case) are encountered and environmental exposures from temperature changes, shock and vibration must be met. A brief review of standard processes will be followed by a selection criteria for the optic, its substrate, the bond geometry, surface preparation, application and cure. Common analysis practices will be compared to Finite Element models. The impact of stress in terms of distortion and level of risk of bond failure is highlighted. Trade-offs will be presented as aids in determination of the best approach. Some areas addressed will be different adhesive types, matching CTE's, stress effects, athermal bonds, monolithic designs, and the use of flexures.
