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By Mark Khinkis, Huajun Yuan, Mark Zak, Yaroslav Chudnovsky, Aleksandr Kozlov

"An afterburner for green petroleum coke calcination in electrothermal fluidized bed was designed, fabricated, installed, and tested on a pilot fluidized bed calcination furnace. The experimental set-up comprised a combustion chamber, in which fine particles and volatiles of the furnace off-gas were fully combusted, and a cooler equipped to calculate the related heat recovery and losses. Off-gas composition was analyzed to evaluate the combustion process. The energy balance confirmed the potential to recover a large part of the heat value of volatiles and fme particles from the GPC. Potential future applications of the results are discussed.IntroductionGreen petroleum coke (GPC) is an oil refining byproduct that can be used directly as solid fuel or as feedstock for the production of calcined petroleum coke [1-2]. GPC contains a high amount of volatiles and sulfur. With coke calcination, the GPC is heated to remove the volatiles and sulfur in the calciner off-gas to produce purified calcined coke, which is used in the production of graphite, electrodes, metal carburizers, and other carbon products. Currently, more than 80% of calcined coke is produced in rotary kilns or rotary hearth furnaces. These technologies provide partial heat utilization of the calcined coke to increase efficiency of the calcination process, but they also share some operating disadvantages [3]. On the other hand, coke calcination in an electrothermal fluidized bed opens up a number of potential benefits for the production enhancement while reducing the capital and operating costs.The increased usage of heavy crude oil in recent years has resulted higher sulfur content in green coke produced from oil refinery process, which requires a significant increase in the calcinations temperature and residence time [ 4]. The calorific value of the process off-gas is quite substantial and can be effectively utilized for combined heat and power (CHP) production to complement the energy demand. Waste heat recovered from the product cooling could also contribute to the overall economics of the calcination process. Preliminary estimates indicated the decrease in energy consumption by 35-50% as well as a proportional decrease in greenhouse gas emissions. So, efficiency improvement of the coke calcinations systems is attracting close attention of the researchers and engineers throughout the world."

Jan 1, 2014

By David J. Barr

Public Law 91-190 - January I, 1970 states that, "The purposes of this Act are: To declare a national policy which will encourage productive and enjoyable harmony between man and his environment; to promote efforts which will prevent or eliminate damage to the environment and biosphere and stimulate the health and welfare of man; to enrich the understanding of the ecological systems and natural resources important to the Nation; and to establish a Council on Environmental Duality." The administrative aspects of this National Environmental Policy Act of 1969 have in essence established the requirement that all agencies of the Federal government assess the consequence of their actions with an Environmental Impact Statement. Furthermore, five states have already enacted environmental legislation, and others will surely follow. The Environmental Services Project Director for Dames and Moore has stated in the June issue of that company's publication, "Elements," that, "The nuclear power industry has perhaps been most affected to date by the Act [NEPAL but recent court decisions, legislative trends and general public concern will accelerate the spread of the Act's impact on other industries. Mining and petroleum are already involved in environmental affairs." There can be little doubt that within a very short time all environmental aspects of the minerals industry will be strictly regulated and monitored by some agency of Federal and/or state government. Indeed, it is probable that any future effort to extract natural resources will be contingent upon a favorable review of an Environmental Impact Statement. It is also quite possible that continuation of present operations will have to be justified on the basis of proof of an acceptable environmental impact. It is the objective of this paper to present some ways in which remote sensing technology can be applied toward an efficient collection of environmental data necessary for the preparation of an Environmental Impact Statement.

Jan 1, 1972

By K. Bullock, M. Levesque, G. Lyle, D. L. Millar

ABSTRACT The options for reducing the carbon footprint of energy use in mining fall into three categories of activity: i) reducing demand, ii) improving energy utilization, and iii) adopting low carbon energy technologies. In addition to the environmental imperative, the economic case for these activities gains higher priority as the prices of electricity, gas, and liquid fuels increase. Low-carbon, energy-saving technology options that are available to mining industry companies lead to projects with return rates that must compete alongside other capital-intensive projects considered by mining company boards. Energy projects frequently involve longer payback periods and lower rates of return than those of competing bids for capital, such as new mineral property developments. For energy services companies that specialize in the financing, construction, efficient operation, and maintenance of energy projects, the same returns and payback periods can be considered acceptable or even attractive.

Jan 1, 2012

By T. S. Lundström, B. D. Marjavaara, I. A. S. Larsson

"The flow field in a rotary kiln, used in an iron ore pelletizing process, was investigated using a three-dimensional computational fluid dynamics model. The model is isothermal, downscaled and simplified. The objective was to examine the possibility of capturing the unsteady motion of the flame seen in the real kiln. The results from the simulations were compared with recorded images of the real process. The results demonstrate the possibility of quickly getting an overview of the flow field in the kiln. The main, unsteady behavior of the flame was captured. The model may be used as a tool in the ongoing work of improving and optimizing the pelletizing process.IntroductionThe pelletizing process, in which the crude iron ore from a mine is upgraded into pellets, is a process involving large amounts of hot air flowing in complex geometries. Flow control is a crucial factor in this process to maintain high pellet quality. The rotary kiln is one of the last steps in the pelletizing process, and this is where the pellets are sintered to increase their strength and metallurgical properties. The kiln burner produces a flame that supplies the entire pelletizing process with the necessary heat.Kiln burner flames are large diffusion flames arising from a jet of fuel from the burner issuing into a concentric confining cylinder with a surrounding coflow of air, called secondary air. To enable combustion, the secondary air needs to be entrained into the fuel jet. This mixing of the fuel and air is the slowest step in the combustion process and therefore affects the efficiency of the combustion. The rate of entrainment depends on the momentum ratio between the burner jet and secondary air. The higher the momentum ratio, the faster the entrainment rate and, consequently, the faster is the fuel/air mixing.The kiln of interest in this study differs from kilns used in other industrial processes in both geometry and operating conditions. A distinguishing feature is the large amount of secondary air being induced through the kiln hood and then transported to earlier stages in the process as air or exhaust gas. The secondary air therefore has a substantial momentum, implying that the resulting flow field has a significant impact on the mixing and combustion process in general and the flame shape and stability as well as combustion efficiency in particular. A systematic study of the factors influencing the dynamics of the flow field in the kiln, neglecting the combustion, is therefore justified."

Jan 1, 2016

By O. C. Blade

"An important function of the Bureau of Mines is promoting the conservation and more efficient utilization of a natural resource. Petroleum is such a resource, and its utilization depends to a considerable degree upon its characteristics. For this reason the Bureau of Mines, over a period of years, has analyzed many samples of crude petroleum by the Bureau of Mines Hempel method 3/ and published complications of crude-oil analyses. Among such publi¬cations are several reports presenting analyses of crude oils from fields in Oklahoma. The most recent of these relates to samples from southern Oklahoma. 4/ The present paper provides additional analyses of Oklahoma crude oils, largely from areas and formations not heretofore represented in published reports. The analyses of 248 samples from 153 fields are presented individually and collectively in the tables of this report.Crude oil has been produced in Oklahoma in commercial quantities since 1891, and peak production was reached in 1947. The State's cumulative production to January 1, 1944, is, according to the American institute of Mining and Metallurgical Engineers, 5,186,466,000 barrels. 5/ The annual production of crude petroleum in Oklahoma for each year from 1891 to 1943, inclusive, is given in table 1."

May 1, 1945

By Y. Yang, L. Li, X. Liu

Coal mining in China is facing the transition from output to quality. Based on the total mining capacity and average production, the current situation of coal mining at mine, city, and province levels is analysed, and data in support for the layout of sustainable mining development and the optimization of output provided. The results show that 87% of China's coal is mined by underground methods, with an average production capacity of 0.93 Mt/a per mine. Open pit mining accounts for 13%, with an average mine production capacity of 5.73 Mt/a. The average mining capacity of coal mines in China is 1.05 Mt/a, with 1181 coal mines with an average capacity less than 0.3 Mt/a, accounting for 35% of the total coal mines but contributing only 4.51% to output. They are distributed in about 48 cities in six provinces, seriously restricting the transition to green coal mining. The coal industry should speed up the closure of small coal mines in key provinces and cities, eliminate outdated production capacity in the central region, increase the speed and proportion of coal resources moving westward, and promote high-quality development of coal mining.

Jan 26, 2023

By Carl Fisher

A microseismic roof fall warning system was field tested in Western and Eastern coal mines in the United States to better define the capabilities and limitations of the microseismic method in predicting roof fall. Microseismic event and energy type data were obtained and documented for twenty-three coal mine roof falls, Field test results indicate that both the microseismic event and energy methods, as applied in this development effort, have a high probability for successful application in a commercially practical roof fall warning system. Based on the results and experience obtained during field testing, a commercial prototype microseismic roof fall warning system was designed and constructed. Although it was the intent of the program to field test the commercial prototype system, delays in equipment fabrication and contract time limitations did not permit field testing.

Jan 1, 1980

By Richard L. Rains

In 1992, the Bureau of Mines evaluated mineral resources of the 34,043-hectare Caribou City and 41,943-hectare Stump Creek study areas in southeastern Idaho. No resources were delineated. The areas had been proposed for wilderness. Rocks underlying the study area are part of the Idaho-Wyoming Thrust Belt. At Caribou Mountain they have been intruded by diorite-monzodiorite. Where the intrusive rocks contact calcareous members of the thrust belt, skarn bodies have formed that host metal deposits. Gold, both placer and lode, occurs in the Caribou City area, and salt occurs in the Stump Creek area. Production records show 73.5 kg (2,363 ounces) of placer gold were produced; however, field studies indicate more than 2,000 kg (67,000 ounces) probably were recovered. Minor amounts of lode gold, silver, and copper were recovered from the hard rock mines. Production of salt from the Stump Creek study area in the 1860's was used by emigrants on the Oregon trail and also shipped to various mining districts for use in silver recovery. Oil and gas were drilled for, but all holes are plugged and abandoned. There are no current leases. Examined workings consisted of 25 adits, 3 shafts, 50 prospect pits, and extensive placer workings all in the northern tip of the Caribou City area, Current BLM records show 168 placer and 146 lode claims; 14 claims are patented.

Jan 1, 1993

By Neha Shukla, Nikhil Dhawan

The current study examines the extraction of rare-earth elements from trichromatic phosphor of discarded tube lights via baking processes. The Y2O3: Eu3+ (YOX) and BaMgAl10O17: Eu2+ (BAM) phases completely decomposed during acid and alkali baking with > 90% Eu and Y extraction. Prior, selective acid leaching of the YOX phase enhanced the acid baking process at a lower temperature (< 230 ℃). Feed acid baking showed a maximum 87% Tb, 36% La, and 17% Ce extraction at 500 °C, 0.5 h, 1 ml/g H2SO4, and alkali baking yielded 16.1% Tb, 86% La, and 73% Ce at 300 ℃, 0.5 h, 50 wt.% NaOH. The acid baking of the acid-leached phosphor yielded 72% Tb, 95% La, 63% Ce, ~ 95% Y, and Eu extraction at 300 °C, 0.5 h, 1.05 mL/g H2SO4. Lower Tb extraction during the acid baking of acid-leached phosphor can be attributed to the formation of Ba3Tb( PO4)3 and BaTbO3 phases. Insoluble Si3Tb5 phase formation and partial decomposition of CeMgAl11O19: Tb3+ (CMAT) phase in the alkali baking route leads to lower Tb extraction. The acid baking process is suitable for extracting Tb, Eu, and Y, whereas the alkali baking process is suitable for La and Ce. The thermal analysis of phosphor and flux interaction depicts that alkali baking is less energy-intensive than acid baking. In comparison, the one-step acid baking process and the two-step alkali baking process yielded desirable extraction results (87% Tb, total RE (rare earth) 78.5% and 50.4% Tb, total RE 59.3%). The product yield in the acid and alkali baking route of feed, acid-leach phosphor is 36%, 29%, and 39%, 28.2%, respectively, with ~ 98% mixed rare-earth oxide purity.

May 5, 2022

By V M. Silva, P A. A Martins, V O. Matthew, A L. S Fonseca, E B. Cunha, A J. D Ferrari, E M. S Silva, A C. Silva, D R. T Vilela

The Anglo American phosphate mine is located in the Brazilian state of Goi&#225;s and possesses one of Brazil’s most important phosphate rock deposits, with the site being the country’s second largest producer of phosphate rock concentrate. Despite the site having been in operation since 1979, the mining team only started using explosives in 2004 when rocks with greater hardness started to appear in the mine’s geological profile. Rock excavation was previously performed mechanically. Until 2013, only rocks with high hardness were blasted, this following the standard drilling grid that was defined in 2004 without any changes in the blast parameters. The aim of this paper is to show how fragmentation optimisation has yielded positive results at all stages of the production chain, from the mine to the mill passing through an impact hammer crusher, a rod mill and ball mill, operating in close circuit with hydrocyclones.While incorporating the mine to mill holistic approach during the operational integration, the focus was on defining the blasting domains and respective optimal fragmentation and measuring the benefits of blasting in terms of reduction in energy and grinding media consumed in the comminution processes. In the first stage, the blasting team made changes to the blasting parameters and assessed the effects of these changes on fragmentation using computer software and on-site measurements. This generated a database that made it possible to divide the mine into blasting domains. For the second stage, teams from the plant, geology, mine planning and operation departments jointly made comparisons between the performance when processing stockpiles, which only included high hardness blasted ore (20–30 per cent of blasted ore). Changing the drilling grid’s size from 3.0 m &#215; 3.8 m to 2.0 m &#215; 2.6 m for high hardness rock with the presence of silicates resulted in a 40 per cent reduction in the P80 for the blasted material (from 459 to 278 mm), while changing the grid from 3.0 m &#215; 3.8 m to 2.6 m &#215; 3.2 m for high hardness rock without the presence of silicates generated a reduction of 25 per cent (from 270 to 204 mm). There were gains observed from the measurements at the mineral processing plant in terms of specific energy spent on comminution and on the consumption of grinding bodies in the rod mill. There was a measured reduction of circulating load during secondary grinding and a reduction in slime generation.CITATION:Silva, A C, Martins, P A A, Silva, E M S, Fonseca, A L S, Ferrari, A J D, Cunha, E B, Silva, V M, Matthew, V O and Vilela, D R T, 2015. Fragmentation optimisation – adopting mine to mill for reducing costs and increasing productivity, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 363–368 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By Burton J. Thamer

Radon emanation coefficients of 0.02 to 0.55 were measured at moisture contents ranging from dry to saturation in eighteen different ores. The emanation coefficients rose from a minimum when dry to a plateau usually starting at 5-20 percent of saturation. A model, using measured pore-size distributions, suggested that the radium mineralization may be confined to annular layers about 0.02 micrometers thick around pores. Radon&apos;s diffusion coefficient was determined as a function of moisture. The techniques involved comparing a disc&apos;s exhalation as a function of time whether or not the disc had a distributed source. The model was free of approximations and included the effects of porosity and adsorption. An increase of diffusion coefficient with moisture for one or two ores was explained in terms of a model&apos;s equation for the diffusion coefficient in terms of both volume and surface diffusion. Radon&apos;s adsorption coefficient was determined on a uranium ore.

Jan 1, 1981

By Matthew E. Meyer

The intent of this manual is to provide guidelines for observing and documenting the installation of ACIP piles. The manual may also serve as a guide for the training of inspection personnel. It is expected that the general guidelines and procedures described in this manual for the inspection and installation of ACIP piles will be supplemented by engineering judgment, local practice, and experience. ACIP pile construction procedures will vary depending on soil, rock, and groundwater conditions. This manual represents a wide range of possible applications in a variety of projects. It is not intended to be applicable in all situations nor replace engineering judgment for any given project. Therefore, an all-inclusive inspection manual is not considered practical or desirable. This manual should not be used to interpret or replace project specifications. It has, however, been prepared to complement the Augered Castin- Place (ACIP) Piles Manual model specification (DFI, 2003).

Jan 1, 2010

This manual is limited to Augered Cast-in-Place (ACIP) piles constructed using a hollow stem continuous flight auger. 1.1SCOPE AND LIMITATIONS The intent of this manual is to provide guidelines for observing and documenting the installation of ACIP piles. The manual may also serve as a guide for the training of inspection personnel. It is expected that the general guidelines and procedures described in this manual for the inspection and installation of ACIP piles will be supplemented by engineering judgment, local practice, and experience. ACIP pile construction procedures will vary depending on soil, rock, and groundwater conditions. This manual represents a wide range of possible applications in a variety of projects. It is not intended to be applicable in all situations nor replace engineering judgment for any given project. Therefore, an all-inclusive inspection manual is not considered practical or desirable. This manual should not be used to interpret or replace project specifications. It has, however, been prepared to complement the Augered Cast-in-Place (ACIP) Piles Manual model specification (DFI, 2003).

Jan 1, 2010

By John C. Brulia

The IME member companies, the ISEE along with its chapter organizations, the Federal, state and municipal regulatory agencies, and the industry consultants and suppliers have developed safety equipment, provided safety guidelines, promulgated safety-oriented regulations, and conducted safety training for blasting personnel in an effort to reduce explosives-related accidents.

Jan 1, 1994

Throughout October, U.S. producers priced unalloyed 99.5 percent aluminum ingot at 53¢ per pound. Dealers, in last month&apos;s domestic market, were quoting unalloyed ingot at a range of 45.5¢-46.3¢ per pound. Costa Rica recently issued a proposal to Japanese aluminum smelters to participate in an integrated aluminum-refining project which would include bauxite development. The project reportedly would include a 600,000-kilowatt hydroelectric power station, a 600,000-metric-ton-per-year alumina plant, and a 300,000-ton-per-year primary aluminum smelter. Two U.S. firms--Aluminum Co. of Amerjca (Alcoa) and Martin Marietta Co.--and several European aluminum smelters are also said to be interested in taking part in this project. Alcoa conducted a feasibility study for the Costa Rican Government in 1970 and estimated the bauxite reserves to contain 150 million metric tons.

Jan 1, 1977

By R. P. King

The MODSIM mineral processing plant simulator is used to find optimal combinations of target separation specific gravities in a typical modem coal washing plant. A plant that is set up with these optimal targets can deliver up to 10% more yield at the same ash content as the same plant set up with separation targets chosen by conventional methods. MODSIM is the only simulator currently available that can simulate the liberation of pyrite and other mineral matter during open-and closed-circuit grinding operations. The simulator can therefore be used to assess the benefits of grinding operations in the flowsheet.

Jan 1, 1997

By R. V. Ramani, R. L. Grayson, R. L. Frantz, V. A. Marple, W. R. Myers, K. L. Rubow, Mutmansky. J. M., T. J. Stobbe

"An investigation of protocols for research performed from 1953 to 1988 on pneumoconioses (with emphasis on diseases related to coal and silica) was conducted in the Generic Mineral Technology Center for Respirable Dust. In addition, interviews were conducted with prominent U.S. medical researchers, aerosol scientists and engineers in government, industry, and universities to determine dust sources, dust preparation methods, laboratory protocols, and determinant variables related to in vitro and in vivo research and assess the comparability of results.Since the original report on the protocol project, additional research regarding free radical existence in freshly produced dust particles and the shape and contamination of particles generated for research purposes has further heightened scientists' concerns. As indicated by current research, fresher dust particles and those with more angular shapes may have a different level of reactivity in biological systems than do older or more rounded particles. Therefore, research on dust preparation methods for biomedical studies was undertaken and will be outlined here.Results of protocol review and interviews are summarized. Research on size reduction methods and their particle characteristics plus some recommendations concerning dust preparation methods and reporting in biomedical publications are also presented. Recent evidence indicates that these recommendations may be of importance in comparing and interpreting research results."

Nov 1, 1995

By Fuming Wang, Xin Lu, Hao Bai, Hebin Zhu

"In this study, CO2 emissions and carbon footprint of a typical steel works with integrated process and iron and steel industry in China was calculated and analyzed by a carbon footprint method based on the model of process CO2 emissions in iron and steel making. The carbon footprint of iron and steel industry from 1991 to 2010 in China showed a rapid increasing tendency. In 2008, the CO2 emissions of iron and steel industry in China was 1.289 billion tons, 19.71% of the national total CO2 emissions, and the corresponding carbon footprint was 159.13 million hm2 of green area. Carbon deficit of iron and steel industry also go up gradually if considering the carbon storage by green vegetation. Thus, the internal carbon reduction strategy, such as energy structure optimization and energy saving technology, was mainly encouraged for the sustainable development of iron and steel industry in China.IntroductionThe Global Warming resulting from the increase of Greenhouse Gases (GHGs), in particularly CO2, in the atmosphere has become the main reason of global climate change, and large emission reductions are required for sustainable development [ 1]. The iron and steel industry is the largest energy consuming manufacturing [2] in the world and the largest emitter of CO2 emissions. In 2005, it accounted for about 20% of global industrial energy use and 30% of energy and process CO2 emissions from industry [3]. In China, the crude steel has firmly been ranking at first of the world recent years and kept growing tendency year by year. With the production growth, the CO2 emissions of iron and steel industry also increased significantly and hence the steel industry has become one of the most sources of CO2 emission in China [4], which has attracted more and more attention to seek the carbon reduction strategies.Carbon footprint is an important and useful concept originating from Ecological Footprint, which was used efficiently to quantitatively analyze the impact of the human activities on ecological system, in particularly impact of the human energy activities [5]. In the view of Life Cycle, the carbon footprint is efficient to analyze the direct and indirect CO2 emission in the whole life of various products used in human activities. As to the iron and steel, the important materials and products in the human life, the carbon footprint analysis is quite necessary to evaluate the CO2 emission impact on the corresponding ecological system and global environmental."

Jan 1, 2013

By Perry Sisk

In order to protect nearby structures during a blasting project, a peak particle velocity limit is often stipulated by a government agency or the owner of a particular structure. At the start of a blasting project, a preliminary estimate for the minimum scaled distance is often determined using a vibration prediction equation before any site-specific data have been obtained. Reasonably conservative assumptions are typically made for the unknown input variables in the vibration prediction equation until site-specific blasting data have been obtained and evaluated. Although this approach is prudent, it provides no assurance that the peak particle velocity values generated during the initial phase of the project will be below the specified limit.

Jan 1, 2013

By Georgene Renner, Chee Theng, William Gleason

"More than 6,300 people attended SME’s 2016 Annual Conference & Expo in Phoenix, AZ and many of them made the trip to the conference to take part in the excellent technical sessions that are presented on a yearly basis by the Society.Holding true to form, this year’s conference was full of options. In fact, this year there were 121 technical sessions and 751 presentations to chose from. The following is a sample of some of the technical sessions as seen through the eyes of the editors of Mining Engineering and SME technical papers.SME Sections Sharing Success: Changing thePublic Perception of MiningThis session was a workshop on how several local sections were effective in getting the message out to their communities and schools about the value of the extractive minerals industry. Several sections shared their outreach successes, including the Mining in Society merit badge activities by the Minnesota Section by Julie Lucas and SME’s participation in the World Scout Jamboree in Japan by Frank McAllister.Dan Alexander highlighted activities by the Pittsburgh Section, such as preparing minerals kits and pamphlets for elementary school classes and regional science fairs. The West Virginia University Student Chapter used the kits as handouts at their local gem and mineral show. School speakers in full mining gear were especially interesting to the young children.Other speakers were Michael Linn, Paradise Valley Unified School District — Business and School Partnerships; and Greg Kruse, Central Wyoming Section of SME — What makes a successful section?Engineering Competency ModelAmerican Association of Engineering Societies and the U.S. Department of Labor, with a grant from the United Engineering Foundation, developed a guide to the set of skills necessary for success in the engineering community -- Knowledge – Skills – Abilities — needed for all disciplines.Various engineering societies are now writing the Tier 5 occupation-specific requirements. The Competency Committee is charged to write concise and discipline-specific mining engineering, mineral processing engineering, geological engineering, and geophysical engineering by Sept. 30, 2017."

May 1, 2016