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By X Zhang, B McFadzean, P E. Ngoepe, B Nemutudi, P P. Mkhonto, S Pikinini

There is still a huge challenge in efficiently recovering the arsenides minerals that are largely concentrated in the Platreef Bushveld Complex which constitutes about 21 per cent of the platinum group minerals (PGMs). Therefore new collectors are required to improve the recovery separation of hard to float minerals, in particular sperrylite. The triazine modifications are promising reagents for mineral flotation and have not been given much attention in minerals processing. The adsorption of sodium 2,6-dithio-4-butylamino-1,3,5-triazine (SDTBAT), sodium 2,6- ditrithiocarbonate-4-butylamino-1,3,5-triazine (SDTTCBAT) and sodium normal butyl xanthate (SNBX) on sperrylite (100) surface were performed to identify a well performing collector molecule. We observed that the triazine collectors preferred to bridge on surface As and Pt atoms through the S atoms. We found that the adsorption energies were in the order: SDTTCBAT > SDTBAT > SNBX, indicating that the SDTTCBAT had strong exothermic adsorption on sperrylite and pyrite. These results showed that the ditrithiocarbamate had a great influence in the adsorption strength on the sperrylite surface. Importantly it was found that the triazine collector had stronger adsorption than the xanthate, which portrayed a promising replacement of xanthate collector. These results paved a way for design of novel collector for sperrylite and other chalcogenide minerals to improve their recovery.

Aug 24, 2022

A recent Evening Post Headline read 'Officialdoms Inertia Risking Millions in Growth Strategy'. The article beneath that headline outlined the difficulties encountered by the Government's growth strategy projects and included the paragraph 'public efforts by Government to brush up communication of the widespread nature of its growth strategy is believed to have been matched by efforts in private by some ministers to overcome their frustration at the constant delay while reports and paper work are moved between departments and through the system'. The article went on to point out that these delays could cost New Zealand millions of dollars in lost overseas exchange savings. We as responsible citizens should be appalled or at least concerned that such costly delays should or even could occur. But those on the outside of the system who spend much of their working life prodding, reminding, pleading, cajoling, even begging, the bureaucracy should be excused a smirk or a smile or even a good belly laugh. The Minister is usually a part of the bureaucracy passing judgment on someone else's proposals. This time the Government has plans of its own. Plans which it wishes to see implemented as rapidly as possible and even with the assistance of the precautionary National Development Act with its 'fast track' provisions those plans have got bogged down in the bureaucratic machine which this Government has done as much as any other to create. In the circumstances, the thought of Her Majesty's Ministers frustrated at the constant delay while reports and paper work are moved between departments and through the system is not unpleasing.

Jan 1, 1982

By S-C Shim, H-R Lee, Y Kang, H Shin

Since iron oxide and silicon oxide are major gangue components in various types of ore, FeO-SiO2 base slag, ie fayalite slag, has been often encountered in pyrometallurgical processes of non-ferrous metals. During most matte production processes such as the smelting of Cu, Pb, and Ni, the FeOSiO2 based slag is inevitably formed and plays an important role in refining crude metal as well as engineering aspects. Recently, similar pyrometallurgical approaches have been attempted in the recovery of valuable metals (Ni, Co, Cr) from wasted secondary batteries. Thus, the viscosity of the FeO-SiO2 based slag has great significance in properly controlling smelting processes. However, when molten metal or matte does not coexist with the slag during the measurement, there has been a serious difficulty in maintaining Fe valance and consequently, the slag composition. In the present research, the viscosity of molten FeO-SiO2 slag was measured in 1573~1673 K using a rotational viscometer. In order to keep the state of iron oxides, the oxygen partial pressure was controlled using CO/CO2 gas mixture. The optimised ratio of CO/CO2 could be calculated using Fe/Fe2+ and Fe2+/Fe3+ equilibria at each temperature. The composition of the slag, particularly Fe valance, after the measurement was analysed with the aid of an inductively coupled plasma – optical emission spectroscopy (ICP-OES) and an automatic potentiometric titrator. The measurement showed that the FeO-SiO2 slag has considerably low viscosity values in the molten state, and it sharply increases as the temperature decreases. In spite of the careful oxygen partial pressure control, a part of Fe2+ was found to be oxidised to Fe3+, with a maximal case reaching about 20 per cent. The increase in viscosity of FeO-SiO2 at low temperatures can be attributed to the composition change due to an unavoidable Fe2+ oxidation. In addition, the relationship between the change in the viscosity and the liquidus temperature of FeO-SiO2 based slag was discussed to understand the composition dependence of viscosity.

Jun 19, 2024

By Hampshire MJ

The tailing retreatment project rated at 10 000 t/day commenced operations in October 1982. The operation consists of dredging, feed preparation, cyanide leaching and carbon-in-pulp (CIP) gold recovery followed by Zadra atmospheric stripping and electrowinning. For the first two years the operation was adversely affected by excessive cyanide consumption and low gold extraction. Investigations demonstrated that the very fine, or slime, fraction of the tailing was the dominant consumer of cyanide and dissolved oxygen. The plant flowsheet was subsequently modified by inclusion of 80 - 100 mm dia. cyclones for slimes separation and a 31 m dia. thickener for water recovery. Treatment of deslimed feed in the CIP plant has reduced sodium cyanide consumption from an average 1.85 kg/t to 1.15 kg/t. The reduced oxygen consumption by the CIP plant feed has resulted in higher dissolved oxygen levels, frequently reaching supersaturation after 4 to 5 h contact time. This has allowed much improved gold extraction from the existing CIP plant capacity. Gold extraction from the mixed pyritic siliceous tailing has improved from an average U prior to desliming to a current 57%. Investigations are continuing on the recovery of gold from the discarded slimes.

Jan 1, 1986

By T N. Little

This review paper presents an integrated and practical insight to blasting geology and its importance. This approach involves developing blasting objective up front and implementing geology specific blast designs. The author refers to this approach as ‘starting at both ends’. There are many human-imposed controls on blasting operations, such as: safety, security, legislative, company standards, heritage, and environmental constraints. Thus it is possible for some operators to lose sight of the controls imposed by nature. This paper demonstrates how site geology controls or influences many aspects of the rock breaking processes and how a focus on this aspect has potential to add considerable value to mining operations. It is obvious that mining companies concentrate their efforts on economic/ore geology (good rock geology). However it is the author’s experience that they also concentrate on engineering geology (bad rock geology) only when forced to do so by the ground conditions, but seem to run out of puff before they apply blasting geology (big rock geology). This paper contains five main sections. In the first section, the impact of geological controls on blasthole drilling is briefly discussed in terms of drill selection, penetration rates, bit wear, blasthole stability, blasthole deviation, and health precautions. In the second section the geological controls on aspects of geometric design are reviewed. These include: hazardous minerals, valuable minerals, selection of the blasting techniques, geological structures, blasting direction, and blasting geometry. Section three overlaps with the geometric design section and deals with aspects related to explosives. Topics addressed include selecting the explosive type based on geology, distribution of explosive charge in space and time, explosive performance, and the rock response to explosive loading. In the fourth section, examples are given of the operational complexity needed to implement a blast to cater for difficult bench geologies, environment constraints, past mining (voids) and need for a high degree of quality control. Section five demonstrates geological controls on blast results. Blasting results include the muck pile characteristics, downstream handling and processing, damage to the remaining rock, and blasting emissions.

Nov 8, 2011

The base metal ore from the hanging wall of White's orebody at Rum Jungle, N.T., is composed of copper and oth.er sulphides in a rock described as a phyllite,.which consists essentially of micaceous minerals with a little graphite.Fast selective flotation was obtained in acid circuit below pH 3·5. In neutral or alkaline circuit flotation was generally slow and selectivity very poor due to the ready flotation of part of the sericite. However, it was found that fast selective flotation could be obtained in neutral or alkaline circuit by either of two treatment methods following pre-conditioning in acid circuit; firstly by decanting or filtering a substantial part of the circuit liquor, and secondly by neutralizing with soda ash or lime, providing the collector was added before neutralizing. Otherwise pre-conditioning with acid brought about no improvement whatever.To explain this behaviour, three possible reasons for the flotation of part of the sericite are examined. There is evidence that some sericite floats because of thin films of either sulphides or graphite, but it seems likely such particles will float under all the conditions investigated.On the other hand, if it is assumed that part of the sericite floats because it is activated by metallic ions derived from the circuit water, a reasonable explanation can be given for the variations in flotation behaviour.INTRODUCTIONWhite's uranium orebody at Rum Jungle, N.T., sixty miles south of Darwin, is mined and treated by Territory Enterprises Pty. Ltd. (a subsidiary of Consolidated Zinc Pty. Ltd.), who are managers of the Rum Jungle project on behalf of the Australian Commonwealth Government.This ore contains a significant quantity of copper sulphides, and a flotation plant recovers a copper concentrate from the tailing remaining after the uranium has been extracted.In contact with the hanging wall of the uranium-copper orebody, a further mass of non-uraniferous sulphide ore occurs, and the present paper relates to the behaviour in flotation of this base metal ore.

Jan 1, 1959

During 2009 the technical services staff at Barrick Gold Corporation's Australian Business Unit conducted a review of their five underground mines that utilise pastefill as the backfill component for these operations. Of the five mines reviewed three use dry tailings and two use wet tailings plants. The primary aim for these reviews was to determine whether pastefill was the right option to be used, and if not, what where the alternatives. The reviews undertaken focus on several areas including, paste plant operation, reticulation and barricade techniques, the geotechnical requirements for pastefill in regards to the current mining methods, the consideration of alternative methods, capital and operating cost histories compared to initial estimates, and a cost benefit analysis of pastefill against other mining methods. The main benefits from the use of pastefill is increasing the extraction of the resource, reducing or eliminating the need to leave pillars. In some mines the use of pastefill is geotechnically driven, to manage high stress environments or mining induced seismicity. A third benefit of using pastefill in some circumstances is that it reduces dilution, however it is considered that this is not a valid argument for most of the mines reviewed. At two mines no alternative to pastefill was determined, whilst differing extraction and filling strategies were potentially identified at the other three mines. The reviews developed cost benefit curves for those sites that had alternative mining methods to assist in determining whether pastefill is the right option to use for any particular stope. At the grades typically mined in each operation, pastefill was the preferred option to use. In all mines, pastefill was determined to be the best option at this time.

Nov 25, 2010

For Australian mining projects, sustainable groundwater use is typically defined as a groundwater extraction regime, measured over a specified planning time frame, which allows acceptable levels of stress and protects dependent economic, social and environmental values (DEH, 2004). This principle is compatible with most stakeholdersÆ understanding of our national environmental objectives, yet the application of this policy on a project-specific scale is not always straightforward. Three examples of sustainability issues in the management of groundwater in mining are presented. These examples highlight each of the three dependent values: environmental, economic and social.

Jan 1, 2006

By A S. Derrington

High-accuracy, solid-state digital reference barometers have proven to be well suited to conducting underground barometric pressure surveys. The only problem is their expense; at least A$4000 each. For this reason, and because barometric pressure surveys are not a routine undertaking, very few mines have been able to justify the purchase of suitable instruments. The author knows of only three Australian metalliferous mines that own them.However, this may soon change given the recent development of low-cost, mass-produced miniature barometric pressure transducers. These transducers were developed to provide an altimeter function in the latest generation of smartphones. The main purpose of the inbuilt altimeter function is to allow the smartphone to be aware of its altitude when the global positioning system satellite signal is lost.This paper describes a prototype barometer that was constructed using one of the most accurate of the latest generation of piezo-resistive smartphone barometric pressure transducers. The prototype instrument was constructed for less than five per cent of the cost of a commercially available digital reference barometer. The prototype was subsequently tested against a reference barometer at the University of Queensland’s Experimental Mine to verify its accuracy and suitability for measuring pressure differences between underground survey stations.It is expected that the instrument’s low cost will pave the way for barometric pressure surveys to become more commonly used in mines. In turn, the resulting improvement in knowledge of major underground pressure losses should allow mine ventilation officers and engineers to optimise their ventilation systems and potentially reduce overall operating costs.An alternative option would be to use a barometer-equipped smartphone as a survey instrument, provided that its inbuilt barometer module is sufficiently accurate.CITATION:Derrington, A S, 2015. Development of a low-cost instrument for barometric pressure surveys, in Proceedings The Australian Mine Ventilation Conference, pp 331–336 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

By B D. Saffron

In 1983, open cut coal mining operations were suspended at the Tent Mountain coalmine, located in Alberta, Canada in an area called Crowsnest Pass. Montem Resources (‘Montem’), an Australian mining company, purchased the asset in 2016. They conducted several drilling campaigns and undertook environmental monitoring with the intent to restart operations. In 2020, Montem completed a Definitive Feasibility Study, which indicated a mine life of more than 14 years.

Aug 2, 2023

Record quantities of slag were produced in 1974. Slag usage in this year amounted to 8.5 mega tonnes for granulated blast furnace slag and 7.7 mega tonnes for crushed blast furnace and L.D. slags. Granulated blast furnace slag is mainly used as a hydraulic bonding material in the manufacture of cement and in road construction. These applications give a fuel saving and reduce processing costs. Crushed blast furnace and L.D. slags find application as a substitute for natural aggregates in road construction and in the production of concrete. There is no doubt of ttie interest to utilise to the maximum all the slag produced by the steelmaking industry, thus preventing the build up of slag heaps detrimental to the environment and favouring the disposal of the heaps formed in the past. World wide efforts are being made to achieve this objective.

Jan 1, 1979

By Martin R. E

L44 Shaft is a major upcast ventilation shalt in the hanging wall of the 1100 Orebody. Various techniques for stripping a raisebored pilot hole were combined to produce L44 shaft. From the surface to 198 m depth, the shaft was concrete lined 7.3 m internal diameter. Below this the shaft was developed to 7.6 m diameter unlined. 11 level, 540 m below the surface, was the first readily accessible level connection. The section to 198 m depth was benched and concrete lined through weak oxidised ground. When more competent ground was encountered the operation was converted to horadiam stripping. This application of the raiseborer has led to a safer, more efficient method of shaft development.

Jan 1, 1977

By D J. Corp

The Halmahera Contract of Work is a sixth generation contract held 82.5 per cent by Newcrest Mining Limited and 17.5 per cent by PT Aneka Tambang and takes in the Gosowong Project area. In 1991 Newcrest Mining Limited established a small exploration office in Jakarta and proceeded to seek exploration opportunities. The Halmahera area was identified as a substantial prospective ground position in a relatively unexplored area. In late-1991 Newcrest Mining Limited and PT Aneka Tambang agreed to explore in Halmahera. Initial field work commenced in July 1992. A vigorous ground reconnaissance programme led to the discovery of the Gosowong deposit a little over 12 months later in September 1993. In April 1997 the Contract of Work was approved covering much of the island of Halmahera. Between September 1997 and November 1998 activities were directed principally towards obtaining the necessary permits required to commence construction activities. Some particularly ambitious targets were set for achieving this outcome. An aggressive construction programme commenced in late-1998. Construction took place during a period of unseasonally high rainfall, which in itself presented additional challenges to the construction team. A key milestone for the project was achieved on 1 July 1999 when wet commissioning of the process plant commenced. Construction of the Gosowong Mine was achieved on time and within budget. A period of some six years elapsed from the initial discovery of the Gosowong deposit to the time of the first gold pour. Much of the permitting, construction and commissioning activity took place between September 1997 and July 1999. This coincided with a period of significant social, economic and political upheaval in Indonesia. During the construction period a high level of importance was placed on the structured recruitment and training of local people, as well as fostering appropriate community and local business development programmes in the communities nearby the project. Emphasis was also placed on environmental management with detailed long-term planning and progressive rehabilitation commencing during the construction phase. The permitting and subsequent development of the Gosowong Project has demonstrated that even during the difficult times, with commitment, it is possible for mining and exploration companies to conduct business in Indonesia.

Jan 1, 1999

By C Kusi-Manu, E Nyamusika

Geita Gold Mining Limited (GGML) is owned and jointly managed by Ashanti Goldfields Company (Ghana) and Anglogold (South Africa). The mine is currently one of the largest gold producing open pit operations in Africa producing 620 000 ounces of gold and mining in excess of 70 000 000 tonnes of material per annum. The mine currently has 2000 full time employeeÆs and a mine life in excess of 12 years. Geita Gold Mine is comprised of 11 different gold deposits situated in the Lake Victoria Goldfields of North Western Tanzania (Figure 1). The gold deposits are primarily associated with banded ironstone formations within an Archaean greenstone belt. Current global resources, including Inferred, stand at 129.5 million tonnes grading 3.91 g/t (16.2 M oz). Open pit reserves total 70.4 million tonnes grading 4.16 g/t (9.4 M oz). The majority of the gold resource is hosted by the three deposits (Nyankanga, Lone Cone and Geita Hill) within the æGeita TrendÆ a large and continuous (>4 km long) mineralised zone (Adofo, 2002). Geita Gold Mine commenced operations in June 2000, as the second large-scale open pit gold mine in Tanzania. The new workforce of 800 people had no previous experience in open pit gold mining. Since the start of the operation, Geita Gold MineÆs management ambition was to become a world leader in the application of best practice in all technical disciplines and in operational success. Staff development and training was identified as one of the major components in the company achieving its aim. Geita Gold MineÆs management has committed the necessary training staff, resources and the commitment of over $US 1 M a year to staff training and development programs for 2003 and 2004. The process and management of Geita Gold MineÆs mining geology staff training and development program is presented in this paper.

Jan 1, 2003

Minerals processing operations use a significant quantity of fossil carbon to provide energy and as reductant. Greenhouse gas emissions from the use of this fossil carbon contribute to the global increase in anthropogenic CO2 emissions to the atmosphere. In the spirit of fostering thinking about a step change in this situation, this paper explores opportunities for the use of sustainable carbon from biomass sources in a range of mineral processing operations. The exploration shows that many common processes are contenders for fossil carbon replacement and that feasible scientific research by minerals processing technologists would add to deeper understanding of the potential for a sustainable bio-carbon based industry. It is also shown that there are many dilemmas on the social, environmental and economic fronts to be solved before a biomass based industry could become a reality.

Jan 1, 2004

By C Garrido, J Barrera, H Alvarez, L Perez, S Ramirez

In recent years, there has had a greater recurrence of studies and projects that consider tailings filtration followed by dry stacking to reduce the consumption of fresh water, the space required for disposal, and, eventually, to reduce the costs of the project. In addition, this technique could be required to meet new environmental restrictions to extend the life-of-mine of existing plants or to enable the development of new projects, especially in areas of high social interest. This article is intended to describe the most relevant technical aspects of the design and implementation of an iron ore tailings filtering system and its final overland disposal as well as physical and metallurgical surveys, and laboratory and pilot testing. Furthermore, it is presented how these activities are inserted in the project development to rationalise the resources. The case under study considers an iron mineral wet magnetic concentration processing plant. The outcome tailings are dewatered by means of thickeners, where the overflow water is recycled back to the plant. The underflow slurry is pumped into intermediate storage tanks before proceeding with further dewatering and final disposal. The project consists of a tailings filtration plant, belt conveying systems, a temporary stockpiling system, trucking loading and transportation system, moisture-conditioning facilities (spreading and airing), and final disposal facilities (compacting). Due to the stickiness of the filtered tailings that governs the belt conveying system design, the operating moisture range must be established. Besides, proper technical aspects such as planning, executing, and analysing both the laboratory and the pilot testing data to validate process design parameters; selecting filters; defining spare filtering capacity; handling the out-of-range filtrated moisture; sizing the belt conveying system; configuring the equipment involved, must be considered.

Nov 8, 2021

Last September, when I was asked to prepare this paper, I was told the subject was "mining," a broad subject indeed! Rather than choose one of the many important technical and economic details which characterize mining today, I turned to a subject which fas- cinates me: mining's image. If we are to survive and prosper into the twenty-first century, and if industry and society are to continue enjoying the material benefits which flow from mining, we must address the melancholy fact that the general public at best does not understand mining, and at worst does not believe it is needed or deserves to continue. While my point of view is largely that of an American mining executive, I would hasten to point out that Homestake has participated in Australian mining for over three decades, and our subsidiary, Homestake Gold of Australia Limited, is now a major producer in this "lucky country." Does society need a viable minerals and metals industry? The answer is obviously "yes," so the challenge is to change some minds: not just those of the amorphous "public," but on a focussed basis targeting journalists, educators, TV commentators, politicians and opinion makers of all stripes (I thought of using "rifle shot" instead of focussed but thought that might be misconstrued). Along the way we miners must also look deeply into ourselves, our attitudes towards the society in which we function, and our willing- ness to change as well as to seek change in others. How did we become such bad guys? More than a century ago mining was not just accepted, it was even romanticised. In America, we had altered the time-honored concept of "Crown" lands into public lands made easily available to settlers pushing back the frontier. Miners even preceded the farmers and stockmen in what was perceived as nation-building, although by the 1890s there was a growing interest in conservation, especially the protection and management of forests and national parks. Even though emphasis was shifting toward government stewardship and away from trans- fer of public lands to private ownership, homesteading and mining were clearly recognised as valid uses requiring not just access, but security of tenure. Indeed, conservation as it was then understood implied management of the public domain as well as its protection. Initially this was no great problem to the U.S. mining industry, but as the nation grew and competing land uses became more important, conflicts began to appear, first over water rights and later over air quality and destructive mining practices. But these were local disputes rather than national issues, and two World Wars, the Great Depression and post-war reconstruction lulled our industry into thinking that nothing had really changed. After the storm began to break in the 1960s, the mining industry found itself confronted by a growing maze of complex and costly laws and regulations. It took us longer than it should have to realise that, in facing this challenge, we seemed to have lost the understanding and support of many of our legislators and a majority of the general public. For over 20 years now, since the first Earth Day in 1970, the U.S. Mining

Jan 1, 1991

It is a very great privilege for me to be able to address you tonight and I am deeply sensible of the honour which has been done me. I am equally sensible of the inadequacy of my training for the position of President of your Institute.May I say at once what a very great pleasure it is to have so many members from the mainland States visiting us here in Tasmania. We do hope that you will find pleasure and profit in your stay.Since the Annual Conference is always held in the vicinity of one or other of the great mining fields, it has become the practice for the Presidential address to review the history of the particular field and t(j) indicate its place in the economic structure of the country.I propose to follow this practice and to try and present to you a short picture of thÇ mineral industry as it has existed in Tasmania. None of the information is new it is available in diverse and remote geological reports and in publications such as Witham's Western Tasmania and the more recent Peaks of Lyell. The last composite approach was written twenty years ago by P. B. Nye and published as a Geological Survey Bulletin.I have enjoyed preparing this address because on occasion I find it refreshing to look back and see what was known and what was accomplished in the days when the going was a little tougher than it is now, and to speculate upon the reasons that drove men to do what they did. I shall therefore discuss the search for minerals in this State; the discoveries over the years; the elation with which the new fields are greeted; the disappointments attending some of them; the mines that have come and gone; and the...

Jan 1, 1958

It is a common misconception that the grant of mining tenure, whether it be an Exploration Permit, Mineral Development Licence or Mining Lease, will entitle the holder to access all land within it in order to explore or mine. The ability for miners to access their tenure in order to undertake activities is critical to the industry. While significant time and energy is quite rightly dedicated to resolving native title and cultural heritage issues before the commencement of mining operations, the same cannot always be said for addressing potential impediments that arise as a result of the overlap between mining and other tenures. Miners should be aware of the overlaps that occur with other tenure and the impact of these overlaps on the minerÆs ability to explore or produce from the area. The existence of an overlap with petroleum tenure, nature refuges, national parks, wild river areas or reserves such as aboriginal land leases are all likely to have an impact on the minerÆs ability to access the area and conduct activities. In some instances, such as an overlap with petroleum tenure, Queensland legislation encourages the miner to reach agreement with the holders of the overlapping tenure. However, in other instances, such as an overlap with a national park, mining tenure is unlikely to be granted at all. This paper summarises the impacts and impediments that arise as a result of overlaps of tenure that are likely to affect mining operations. It also provides examples of how these impediments can, if possible, be overcome under Queensland legislation.

Jan 1, 2007

By W Z. Liu, Q Q. Shi, H T. Yang, X L. Zhang

In order to improve the cutting blasting effect of dimension stone mining, the water coupling directional cutting blasting technology was put forward. Based on the test apparatus and special charge configuration, the mechanism of directional cutting blasting was analysed. Directional device changes the initial equilibrium of the total energy of shock wave effect on blasthole wall. The initial directional crack first appears in the blasthole wall that makes contact with the directional device. Then, two cracks are connected along the direction of the blasthole centre line under the action of detonation pressure and water wedge. The plexiglass tests showed that water coupling directional cutting blasting technology produced cracks along with the predetermined direction completely. The cutting surface was smooth and only a few short cracks appeared around the blastholes. It proved the validity of this technology.CITATION:Liu, W Z, Zhang, X L, Yang, H T and Shi, Q Q, 2015. Directional blasting rock cutting technology, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 815–818 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015