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By L Vimercati, R Williams

Transitioning to a green future requires the mining industry to adopt sustainable practices. Filtered tailings are become a key expectation of the communities we operate in and are growing in a number or mining commodities including bauxite, nickel, gold and iron ore. The filtration technologies required range from dewatering screens to vacuum and pressure filters. Particular challenges faced in iron ore applications include large scale which means several units of large size are often required. In addition, a high specific gravity that cause sedimentation issues and a high abrasion level make demands on achieving reliability level at above 90 per cent. This paper describes the testing, selection criteria and specific features required to provide a rational option for equipment and plant design. An example of how this has been applied in an iron ore application in Brazil is used to demonstrate a successful outcome. This project installed four overhead beam filter presses each producing around 200 t/hr utilising a recessed chamber plate, feed pressures up to 15 bar, cake thickness of 5 mm. The moisture lower than 20 per cent that was produced was considered to provide material with handling and geotechnical properties to guarantee a safe stacking. Regular high pressure washing at 100 bar was considered imperative to maintain cloth life and process performance. The correct management of the system (OPEX control) by PLC control ensures a balance between machine potentials and plant needs. With this equilibrium it is possible to limit mechanical wear preserving equipment lifetime.

Sep 18, 2023

By E. R. Packer

"The mill of Anaconda Britannia Mines is located on the eastern shore of Howe Sound, approximately 32 miles north of Vancouver, British Columbia. The mill has a daily capacity of 3400 to 3500 tons and at the present is treating chalcopyrite-pyrite ore from which only the copper mineral is concentrated. For a clear conception of concentrate filtering and shipping practice at Britannia perhaps a bit of past history should be related.For many years the mill concentrated copper and zinc minerals and intermittently a pyrite concentrate was produced. It was general practice to ship copper concentrate by towed barge down Howe Sound, across Juan de Fuca Strait and thence down Puget Sound to Asarco's smelter at Tacoma, Washington. Zinc concentrate was loaded in hopper bottom rail gondolas spotted on rail barges and towed to rail heads in Vancouver, thence by rail to Anaconda Reduction Works in Great Falls, Montana. Most of the pyrite produced was shipped by ocean freighters to Japan and Taiwan with an occasional barge load of 2000 to 4000 tons to nearby customers in Vancouver and the state of Washington.In recent years, because of smelter shut-downs for one reason or another, mostly strikes, a considerable amount of copper concentrates has been shipped by ocean freight to Japan and in 1971 several lots were loaded in gondola cars and shipped by rail to the Anaconda smelter in Anaconda, Montana, because Asarco's smelter was forced by municipal and state anti-pollution laws to limit the amount of S02 emission from the smelter stacks. Zinc concentrate production was halted in the early part of 1Y70 because of zinc depletion in the ores and pyrite production was stopped in May, 1971, because of a lack of markets.Filter equipment in the Britannia mill consists of conventional disc vacuum filters and reciprocating vacuum pumps. The copper concentrate filter was installed in 1923 as a 6 x 8'6"" American disc type manufactured by United Filter Corporation, The zinc concentrate filter, now converted as a spare for copper concentrates, is also a 6 x 8'611 American disc manufactured by Traylor Engineering and Manufacturing Company and was installed the same year. Formerly, there were, in addition, two 4 x 6' disc filters for pyrite and two 6 x 6' disc filters to de-water bulk flotation concentrates ahead of the regrind mills. Installed vacuum pumps were two Ingersoll Rand 22"" x 811 and one 22"" x 9"". One of the smaller machines has since been scrapped.At the time of the writer's transfer to Britannia in 1965, the entire filter system was operating as a unit using two vacuum pumps and a common filtrate tank with a 2"" SRL filtrate pump for five operating filters. The regrind and pyrite filters were in continuous operation and the co11p('r concentrate filter alternated with the zinc concentrate filter because both copper and zinc concentrates were transp0rted to storage by the same conveyor belt."

Jan 1, 1972

By J. S. Whatley

The properties, origin and industrial uses of kaolin clay are briefly reviewed. The general waterwashed beneficiation process is described. Yost aspects of filtration and solids-liquid separation as practiced in the kaolin industry are mentioned along with devices that are currently in the developmental stage. The paper focuses heavily on the well known art of rotary vacuum filtration, including general construction and operating details. Devices under investigation that might be used to mechanically or electrically dewater clay slurries to higher cake solids levels than can be achieved with rotary vacuum filters are described briefly.

Jan 1, 1986

By Stephen Liu

Tunnel excavation while mining is not often performed in North America primarily due to access constraints in both operations. Referencing European approaches for long distance tunneling, the Devil?s Slide Tunnel project has applied innovation and technology to provide the ability to overcome this unique challenge. The Devil?s Slide Tunnel requires the construction of twin bore tunnels excavated based on sequential excavation method (SEM) construction methods using New Austrian Tunneling Methods (NATM) principles. The twin tunnels are approximately 9 m (30 ft) in diameter and 1,250 m (4,100 linear ft) in length. The purpose of this project is to reroute Route 1 from around the Devil?s Slide through the San Pedro Mountains crossing from Montara, CA along the south and into Pacifica, CA in the north. The Caltrans project was awarded in December 2006 for a total of $272,366,000. The job is an A+B job, thus the estimate scheme of final lining while tunnel excavation is important to save time. A+B is a method of rewarding a contractor for completing a project as quickly as possible. By providing a cost each working day, the contract combines the cost to perform the work (A) with the cost of impact to the public (B) to provide the lowest cost to the public. Concurrent mining while lining is achieved through a series of gantries and a set of tunnel forms allowing the pass-through of the excavation equipment. The tunnel lining operation passes through several phases of work that are dependent upon the progress of the tunnel excavation process. This involves unique milestones, such as the evolution of the ventilation system, development of an enlarged cross passage to allow equipment to access each tunnel from within the tunnel and, finally, the installation of an invert prior to arch lining that limits the continuity of the final lining operation.

Jan 1, 2011

By Christophe Bragard, Rebecca Reeve

The Regional Connector Transit Corridor (RCTC) Project is a 1.9-mile-long metro light-rail extension project that traverses the historical core of downtown Los Angeles, California. This project aims to improve mobility throughout downtown LA with fewer transfers for riders. It is designed to connect two existing rail lines for a more seamless travel. The project consists of twin bore tunnels, three new stations, and is scheduled to be completed in 2022. The design-build contract was awarded to the Regional Connector Constructors (RCC) in 2014, a joint venture of Skanska and Traylor Bros, Inc. with Hatch Mott MacDonald as the designer. One of the challenging aspects of the project was the construction of a crossover cavern in a narrow public right-of-way surrounded by historical structures. RCC used Sequential Excavation Method (SEM) to construct the crossover cavern measuring 287 ft long by 58 ft wide by 36 ft tall. The initial lining of the cavern featured a 12 in. fiber reinforced shotcrete lining. The initial lining was separated from the final lining by a hydrocarbon resistant membrane, as specified by the standard requirements of Metro. The cavern features a cast-in-place final lining with a thickness of 5 ft 9 inches in the invert and 18 inches in the crown and walls. The structure also features a nonload bearing plenum slab and interior walls for ventilation.

Jun 13, 2021

By David M. Koogler

If you are contemplating starting a small coal mining operation there is a good possi¬bility that you can not afford it. If you, have already started, you may be on the road to bankruptcy. If you are a small but well established operator you may be trading dollars, or even dissipating your capital, equipment and other assets. A bleak outlook? Yes! Meant to be discouraging? No! Just a reminder that, with todays costs of doing business, high interest rates, rapidly increasing costs and decreasing sales prices, a small businessman/miner had best watch closely or he will be mired in something worse than a soft bottom - namely a cash and credit shortage, and in too many instances In recent times, bankruptcy. We will not dwell on what happens once you are that far gone, though I could cite a good example. But, let us look at what should be done to avoid such a catastrophe.

Jan 1, 1981

By D. A. Karvonen

Although the economy in the Province of Saskatchewan has historically been agriculturally oriented, a major new source of wealth has been realized through natural resources such as petroleum and natural gas, coal and uranium and since the 1960's - potash. Potash or potassium chloride, in the form in which it is presently produced in Saskatchewan is used primarily as fertilizer, a source of potassium, one of three essential elements required for healthy plant growth with about 5 percent of production sold to the chemical industry for use in such products as soap and liquid detergent, glass and ceramics, textiles and some pharmaceuticals. Saskatchewan is estimated to have approximately 40 percent of known world potash reserves and its ten active mines account for some 25% of annual world production. The development of this resource was recognized to be important to the development of Saskathcewan. In an effort to guarantee a fair and lasting economic benefit to the Province of Saskatchewan the Potash Corporation of Saskatchewan (PCS) was created on February 4, 1975 through an Order-in-Council under the Crown Corporation's Act and later on April 1, 1976, the Potash Corporation Act provided for its continuation. PCS was given the mandate to acquire ownership of a significant portion of the potash mining capacity in Saskatchewan and to establish an organization capable of operating the facilities, marketing the product and conducting all of the other activities necessary for a successful corporation competing in the world potash industry.

Jan 1, 1983

By Wallace W. Wilson

It scarcely 1s possible to read a new issue of any of the principal mining trade journals without noting some mention of a major new overseas mining venture with which one or more domestic companies are involved. These projects seem to follow a fairly consistant pattern; most are large open pit mines, with relatively low grade ore bodies but huge reserves; the total price tag will be in nine significant figures and around half or more of the total cost will be for infrastructure. West1 noted that nearly $7 billion is being invested annually for new mining projects and the expansion of existing mining ventures, in the free world. He anticipates that by the year 1975 such investments would reach the $10-11 billion annual figure, and that in the five year period 1972-76 total capital requirements can be expected to aggregate around $45 billion. The proportion of this total investment which will be financed in some manner is difficult to estimate because of the variety of available financing arrangements. West estimated that around 75% of the total capital would come from internally generated funds, with the balance from external sources. Conceivably a substantially higher percentage could be attributable to external financing, especially it the trend of recent mineral development in Canada and Australia is any criterion, and of course, including local sales of equity as a part of the package.

Jan 1, 1973

By Christian F. Baiz

Industrial minerals can have similar financing requirements to those needs of metaliferrous and coal mining projects. Although, one may see many similarities in the fundamentals of the various risks that must be evaluated in lending to any specific project, one of the outstanding differences is the understanding of the many different markets that these industrial minerals represent. There are in excess of 30 principal industrial minerals ranging in terms of annual production from the largest quantity such as sand and gravel, to possibly the smallest quantity of production of a legitimate industrial mineral which may be defined as industrial and rough gem diamond. If we assume that it is necessary to finance independent projects of ore bodies of industrial minerals for development, the financing techniques are similar to the fundamentals that we would use for financing coal projects or metaliferrous deposits. Therefore, let's begin by redefining project financing in the traditional banking or private sector area, and then in the later development of this paper, we will apply these techniques to industrial minerals in general and cite it with several specific examples.

Jan 1, 1982

By William L. Young

I think I should let you in on one of Canada's best-kept secrets, if you will promise not to tell it all over the place. Believe it or not, good, honest, enterprising capitalism is still alive and flourishing north of our common border, and I am living proof that capitalism is still working for the little guy. My personal story of mining development in Canada isn't all that rare -- you've probably heard something like it from other areas and other days several times -- but my case brings it up-to-date. I would like to Tell you briefly the history of Northumberland Mines Limited, a contemporary case of individual enterprise getting a mining operation underway. And if I can do it you probably can too.

Jan 1, 1981

By Peter A. Allen

INTRODUCTION Lac Minerals Ltd., a significant North American producer of gold and other metals for over three decades, recently completed the financing for its third discovery in an eight year period. From 1975 to 1982, three important gold deposits in Quebec and Ontario: namely Bousquet, Doyon and Hemlo, were located and tested by company geologists. When current development plans are complete, Lac will have injected $400 million into these deposits. A discussion of these projects and their financing reveals some extraordinary challenges faced by top mining management. Responses to these challenges developed by Lac management may interest executives planning to proceed with new North American gold or base metal mines. MINE DE BOUSQUET In 1976, we explored a property containing a large low grade surface gold deposit. The geologial setting was exciting and we tested recent rethinking about the volcanigenic genesis of gold and base metal occurrences. These ideas helped pus to persist in drilling a nearby conductor and 600,000 ton, 0.22 ounce/ton orebody was outlined. With gold at $Cdn.150 per ounce the feasibility was approved and work started February 1978. Availability of a company custom mill 35 miles away reduced our immediate capital needs to $8.5 million. First of all, understanding the geological significance of results at Bousquet was critical. Mine and surface exploration geologists at Lac are continually and closely working together to better understand the nature of gold deposits in the Shield. This management emphasis on both pure and mine geology meant that a much larger ore reserve could confidently be predicted. (A proposal to quickly develop and ship the ore to a nearby company mine was discarded.) Instead of designing just for the initial plan of 500 tons per day we therefore included headframe, shaft and hoisting capacity for 1,700 tons and provided a compartment for future shaft deepening. These prebuilt additions were welcomed within two years. The type of collaboration whereby surface and mine geologists make study and field projects of each other's problems sets the foundation for this predictive ability. At Lac, the traditional responsibility for and supervision of the mine geologist by the mine manager is modified by this collaboration. This adds interest and scope to the geologist's work and lets him think beyond production requirements. Besides such management considerations, dedicated, professional geologists with integrity and lots of practical experience are needed to plan successful developments like Bousquet. Second, projecting future bullion revenue was critical and our experience selling production for future delivery gave us a way to ensure that loan repayment at term would not be jeopardized by falling metal prices. Output from a single mine is often reduced or curtailed for numerous reasons, so "selling forward" is done best and with least risk by companies like Lac with more than one or two producing locations for that metal. At first, a forward marketing program was considered unwise, speculative and unorthodox by analysts and other producers. Declining markets in the early 1980s prolonged gold project capital recoveries however, and critics were better able to appreciate the usefulness of such a tool. The notion that gold miners shouldn't sell forward is rooted in the belief that long-run gold prices will rise as modern social theory implementation in democracies inevitably erodes currency values. Selling against this trend goes against this industry belief or "ethic" and is at odds with the company shareholder who expects the gold price to rise not fall. Nonetheless, an efficient tool is available to the gold producer (not to most other metal producers) to quickly disengage from adverse price trends or to lock in spot prices instantaneously for two years or more of profits. Gold had recently retreated from U.S.$200 to $104 and now had reversed to $150. Lac had been forced to close several of its producers during the late 1960s because central bank-controlled

Jan 1, 1985

By Barrie A. Wigmore

There are two aspects of financing western coal development -- whether there is going to be enough money to finance the prospective large development of the industry, and the specific techniques of raising money for that development. To take the first question of whether there is going to be enough money around to finance your industry, I think it is quite clear that the restrictions on the development of western coal are going to be non- financial. Environmental impact problems are creating the greatest delay in coal mine development, at the moment; but getting enough personnel, mining equipment, railroad equipment, and failure of the Department of Interior to act on leasing federal coal lands all appear likely to create significant bottle- necks in the development of western coal -- larger bottlenecks than financing. Financing appears straightforward for the industry. There are many projections of the financing required to meet Project Independence goals. The National Academy of Engineers estimated that development of 500 million tons per annum of western coal would be necessary by 1985 to meet the Project Independence goals which might require $20 billion of capital spending. It is generally agreed that 500 million tons a year is not a realistic possibility. Carl Bagge?s estimate of production of 250 million tons a year by 1983 appears a more reasonable projection. Development

Jan 1, 1976

By The Staff

THE object of the work was to increase the capacity of the plant and, if possible, to reduce costs of the actual unit grinding while doing so. The accompanying assays of an infra-sizer analysis of the cyanide tail (Table l) illustrate the problem in hand. The cyanide tail is a combination of two products, gangue and FeS2. The assay alters by virtue of a change in gold value due to grinding and the relative quantity of FeS2 in the sizes, which itself varies with the grind. The disposal tail is the residue after the cyanide tail is scavenged by flotation, most of the pyrite being removed for roasting. It presents a somewhat different problem, since grinding gangue is all gain, but -10 micron FeS2 does not float nearly as well as + 10 product. This results in compromise in the final size to be aimed at. Extra grinding has hardly any appreciable effect on the gold extraction from the FeS2. (See Milling Investigations Into the Ore as Occurring at the Lake Shore Mine; Trans. C.l.M.M., Vol. XXXIX, 1936).

Jan 1, 1940

By Dietmar Freyhammer

Grinding is the last stage of the comminution process. In the grinding process the particles size are reduced by impact and attrition stresses. The fine grinding of ores is nowadays finding increased application due to depletion of coarse grained, easily processed ore bodies and the increased need to process distributed fine grained deposits, such fine ground iron ore powder is the basis for the pelletisation process. Depending on the ore type and the project environment different approaches to comminution are requested to provide an adequate ground iron ore for the pelletisation process. Currently the ball mill is the most used equipment in grinding iron ore for pellet feed. Based on the various examination and investigation of minerals on grind ability related to the throughput, to the resulting sieve characteristics and necessary energy consumption, the mill circuit can be: Open dry circuit. Closed dry circuit Open wet circuit Closed wet circuit. CEMTEC GmbH is a renowned name worldwide and offers tailor made solutions to cope these issues.

Sep 1, 2012

By P Pieterse

Kumba Iron Ore Ltd is currently commissioning the Sishen Expansion Project (SEP) û a brownfields project on the Sishen Iron Ore Mine located in the Northern Cape Province, South Africa. SEP is designed to produce 13 Mtpa of product from 21.7 Mtpa of ROM feed. The beneficiation section of SEP employs jigs to process narrow size fractions in the 25 x 0.8 mm size range. The -0.8 mm fraction is screened out ahead of the jig plant and rejected as waste without any prior beneficiation. The processing of this fraction was not included in the early stages of SEP development because no suitable beneficiation or dewatering technologies could be identified within the time-frame required to implement SEP. This paper presents the SEP 1B project, ie the metallurgical and process engineering study that was done to evaluate the techno-economic viability of processing the -0.8 mm material of SEP. To support this evaluation, metallurgical bench scale testwork was done on selected samples characterising the material types used in the SEP for gravity concentration beneficiation. Subsequently, pilot testwork on a 300-ton bulk sample demonstrated that an integrated teeter-bed/spiral circuit could be used to successfully beneficiate the -0.8 mm fraction. The study has established the viability of the proposed process and has concluded that approximately 390 000 tpa could be produced and added to the SEP fine ore product without violating the applicable product specifications. The proposed process has been designed to be implemented in modular units in order to facilitate implementation and ensure future expandability. Based on the recommendations of the study, approval has been granted for the detail design feasibility study. Production is scheduled to commence in the first quarter of 2010.

Jan 1, 2008

By Mingxia Liu, Qi Liu, Tao Jiang

"In addition to physical parameters such as small mass and high specific surface area of fine and ultrafine minerals, chemical parameters such as the adsorption affinity of collectors on the minerals also plays an important role in fine particle flotation. In this study, we have examined collectors with two different ionized groups, carboxylate and hydroxamate, on the flotation of fine niobium oxide (pyrochlore). To facilitate comparison, two hydrocarbon radicals were tested: octyl and oleoyl, which led to four collectors that were studied: octyl hydroxamic acid (OHA), sodium octanoate (C8OONa), oleoyl hydroxamic acid (C18HA), and sodium oleate (NaOl). Small-scale flotation and isothermal microcalorimetric titration measurements were performed to determine the flotation recoveries of different sized pyrochlore and the enthalpic behavior after adsorption of the collectors on pyrochlore. It was found that the flotation performance of the carboxylate-based collectors was generally inferior to hydroxamate-based collectors. Sodium octanoate could not float pyrochlore irrespective of the particle size of the pyrochlore tested. With a longer hydrocarbon chain, sodium oleate was effective to float the relatively coarse pyrochlore (>20 µm) but its collection efficiency dropped sharply for particles smaller than 20 µm. On the other hand, the two hydroxamate-based collectors, octyl hydroxamic acid and oleoyl hydroxamic acid, showed good collecting ability to both the coarse and fine pyrochlore. The isothermal microcalorimetric titration studies indicated a consistent correlation of chain length with floatability of collectors for relatively coarse pyrochlore, as well as a positive relationship between the adsorption affinity and fine pyrochlore flotation recoveries. The key finding of this study was that efficient fine particle flotation could be achieved when strongly chemisorbing collectors were used.INTRODUCTION The first detailed study of the effect of particle size on flotation was made by Gaudin (1931) with sulphide ores. In 1942, Gaudin again demonstrated that (Gaudin et al., 1942) fine particles possess different flotation properties from larger particles. Since then the effect of particle size on froth flotation has been an important research topic by many researchers, e.g., Gaudin (1957), Miettinen et al. (2010), Warren (1976) Jameson (2010), summarizing the behavior of fine particles in terms of their low particle momentum, leading to low rate of collision with bubbles which reduces the chance of adhesion. The suggested remediation methods are mainly based on two approaches: increasing particle size or decreasing bubble size (Warren, 1976). Sand-fine splitting followed by separate flotation treatment of the sand and fines, using deep flotation cells, using starvation quantities of collectors, and using long flotation times, are also strategies to address the problems of fine particle flotation."

Jan 1, 2018

By M. S. Moholwa, J. D. Steenkamp, H. L. Rutto

Manganese ores are the major source of manganese for the production of manganese ferroalloys. There is a gap in the knowledge of the decrepitation behaviour of manganese ores, which presents a problem in the operation of smelters. Decrepitation, which is the breakage of the ore particles upon heating, is an important quality parameter for these ores. The purpose of this investigation was to determine the extent to which South African manganese ores decrepitate during preheating in a rotary kiln. The effects of temperature, rotational speed, and particle size decrepitation were investigated. Manganese ores were heated in a laboratory-scale rotary kiln at temperatures of 600, 800, and 1000°C, and rotational speeds of 3, 6, and 12 r/min. The size ranges were +6-20, +20-40, and +40-75 mm and the residence time was constant at 30 minutes. The decrepitation index (DI) is quantified as the ratio of the mass of <6 mm particles after pre-heating to the total mass of the sample. It was found that the DIs for all ores used were proportional to the temperature and the rotational speed and inversely proportional to the particle size range with temperature being the most important parameter. Ore A was the most susceptible to decrepitation followed by ore C and ore B; this was mainly to the decomposition of kutnohorite, the content of which was the highest in ore A and the lowest in ore B.

Nov 30, 2022

By Shibu John

Rising energy demand and steadily decreasing quality of raw materials due to the global resource depletion are great challenges to the steel production today. The FINEX® Process has been developed jointly by POSCO, Korea and PRIMETALS Technologies Austria, to provide the iron making sector with the capability to lower hot metal production costs, environmental pollutions and to increase the flexibility in terms of operation and the choice of raw materials. FINEX® is a new technology combining a gas-based reduction in a series of fluidized bed reactors and a reduction smelting in a melter gasifier. Commenced in April 2007, the first 1.5Mtpa commercial plant has demonstrated the competiveness as an alternative iron making route. Another 2.0 Mtpa, third generation FINEX® (3G) plant was recently installed at POSCO, Pohang Works and has been operating satisfactorily since its blow-in in January 2014. Based on the well-proven plant concept, new process features, the highly competitive production costs and environmental advantages, the FINEX® Process can be considered as a competitive alternative to the conventional blast furnace iron making route.

Aug 17, 2017

By O. E. Wheeler

The term "finite element analysis" is heard and seen in print a great deal these days; a few words on what precisely it is are in order. In the broadest sense, finite element analysis is an application of an idea developed by a nineteenth century mathematician named Rayleigh. His basic idea was to decompose any problem in mathematical physics into a large number of simpler problems, solve the simpler problems, and then put those solutions together to form an approximation to the solution of the original problem. The scheme works nicely because of two features: first, much of the difficulty in solving practical problems of mathematical physics stems from irregularities in the boundaries and the simpler problems can be chosen with regular boundaries and second the smaller problems are solved for small physical areas where simple approximations of the solution do not differ much from the true solution. In the narrower sense, in which we are now interested, finite element analysis is a technique of using imaginary simple structural elements to construct analytical models of real structures. A direct parallel with the Rayleigh approach exists since the "finite elements" have simple boundaries and are restricted to simple behavior within a single element. Although the correspondence between Rayleigh&apos;s ideas and finite element analysis is now widely recognized, the computational tool, as it has developed over the last thirty years, comes not from the discipline of physics but rather from that of structural engineering. It is interesting that it came not from the traditional research community, the universities, but instead from working

Jan 1, 1974

By Jose a. Sanchidrian, Ramon G. Eguren, Javier L. Amigo

On December 2013 a MEMU exploded at a blasting site in Norway, after burning for more than two hours. This paper describes the analyses made to determine the actual yield of the explosion, the lessons learned from the event and the actions taken as a consequence. The conclusions of the analysis were the following: - The yield of the explosion was 650-1450 kg TNT. In terms of AN and ANE they correspond to 1300 – 3700 kg AN, or 950 – 2450 kg ANE or ANE/AN blend. These quantities are 8 to 31 % of the explosive precursors in the truck. The burning of the truck and its load for two and a half hours had consumed more than two thirds (perhaps up to 90 %) of the explosive precursor material.

Jan 1, 2016