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By A. Rajoria

A dynamic process model for predicting the fluidized bed roasting of copper concentrates with high arsenic content is presented in this work. Mass and energy balances were performed based on roasting mechanism derived from thermodynamic data of species. The reaction rate data, obtained from pilot plant studies on major reactions, were used in tuning the kinetic parameters of the model. DEAS, a dynamic simulation package, is used in setting up the fluidized bed roaster plant model. The effect of process parameters such as concentrate feed rate, concentrate composition, airflow and cooling water rate on the temperature and conversion of roasting reactions are analyzed. The plant model captures the highly transient conditions occurring during the plant start-up, shutdown and other process perturbations. The application of this model in constructing a virtual plant environment for validating the operating procedures and operator training is presented.

Feb 23, 2014

By S. D. Thompson

Several discrete-event simulation models have been developed for designing the conveying system capacities of underground coal mines. Most of these models require the use of a step-function approach to mimic the loading process at each conveyor loading point. Over the years, practitioners have generally employed one of three versions of the step-function approach. An important issue is how these three versions compare to each other in terms of simulated capacity requirements for belt conveyors. Another is-sue is how they compare to peak capacity design. This paper addresses these issues by statistically and quantitatively comparing their simulation results. The consequences and problems associated with using each version are also discussed and summarized.

Jan 1, 1997

By Thomas A. Gwynn

When Lewis and Clark first pushed their boats up the Missouri River, Meriwether Lewis reported the presence of coal in the western states by saying in 1802 that it "burnt tolerably well and afforded but little flame or smoke but produced a hot and lasting fire". Lewis would have been amazed and bewildered at the history of coal development in this region and the more recent political-socio-economic-environmental confrontations of today. Certainly without this coal the railroads would not have readily pushed into our western states, and the progress of this region would have suffered. The coal industry has passed from a period when "coal was king" to a period of depression in the industry, but its importance is being revived. A contributing and simultaneous environmental concern has emerged in the nation and in many states during the past ten years, partly caused by newly imposed standards for sulfur content of fuels. Much of the midwest and eastern coal cannot be used because of high sulfur content, shifting attention to the low sulfur coal deposits of the western states. In the western states, lands disturbed by strip mining or even underlain by strippable coal are small compared to the total acreage, and usually mining operations are on lands not under cultivation. There are some farm lands being disturbed by surface mining, but this is often over-emphasized. In states like New Mexico and Arizona the percentage is less. The value of the minerals underlying the surface certainly must be considered along with the value of the surface, and sometimes proper reclamation following mining can result in higher ultimate usage of the land.

Jan 1, 1974

By Oliver W. Marsden, John O. Marsden

This paper presents the results of a hypothetical case study that evaluates the potential transition of a large copper mining and extraction operation to 90% renewable energy. The case study considers three phases to accomplish such a transition; phase I considers installation of renewable power generation at the site to meet a portion of the current electric power needs, phase II considers conversion of diesel combustion mining equipment to electric equipment, and phase III considers implementation of renewable energy generation coupled with energy storage systems to provide approximately 90% of the total mine site energy requirements. The paper evaluates the results in the context of a range of purchased electric power unit costs ($0.065, $0.100, and $0.135/kWh) as well as various carbon tax scenarios ($0, $5.00, and $37.30/t CO2). While the case study is hypothetical and considers a range of assumptions, it clearly identifies a pathway to potentially economically viable transitions to a renewable energy platform for mining companies. This represents an approach that mining companies can use to help to meet emissions targets, as well as social responsibility and reporting requirements.

Jun 4, 2021

By Robert D. Harris

In 1958, the coal industry, through Bituminous Coal Research, Inc., and the electric utility industry, through the Edison Electric Institute and the Association of Edison Illuminating Companies, initiated a joint program to study coal pyrite and its removal as a means of lowering the sulfur content of steam coals. It was assumed that significant amounts of pyrite often remained in washed steam coal not because available systems for coal cleaning were inadequate, but because the pyrite was small and widely disseminated, During the first two years, samples of coal were examined petrographically to determine the size, association, and mode of occurrence of the pyrite in the raw coal and in the products of laboratory separation, Samples of coal were also pulverized in different equipment to determine how effectively pyrite was released by pulverization and if the mode of pulverization affected the liberation of pyrite. From these studies, the following tentative conclusions were made (1 ): 1. Much of the coal pyrite is within a 250-70 micron size range, and therefore is too small to be removed by conventional coal cleaning, but relatively large when compared to the size of coal as pulverized for combustion in large boilers. 2. The degree of pyrite liberation is mainly determined by the size of the product and not by the type of crusher. 3. For improved pyrite removal, the coal should be cleaned during or after pulverization at the power station.

Jan 1, 1965

By James T. Baxter

Underground mining of limestone is becoming increasingly attractive in Illinois. Most quarries are near rivers on the western and southern borders where competition for land use is intensive. Increasing demands for stone can be met by expanded mining with access by edits in existing quarries and by inclines and shafts at downdip sites. Geologic, hydrologic, and engineering conditions indicate that deep mines in the Ste. Genevieve, St. Louis, Salem, Ullin, and basal Burlington Limestones of Mississippian age and in the Moredock Limestone Member of the Dunleith Formation of Ordovician age are possible, but development will require prudent exploration and planning to ensure that the product will be of good quality.

Jan 1, 1978

By K. V. Raj

As open pit mines continues to grow deeper, managing air pollution can become challenging. During arctic air inversion, the temperature of the air over the mine increases with altitude, and the cold, heavy, surface air is trapped in the pit. This problem is complex, and any solution will require an extensive understanding of the interactions between the aerodynamic movement of air, air inversion, meteorology, pollutant sources, and transport phenomena in the open pit mines. The availability of computational fluid dynamics (CFD) has elucidated the pollutant flow mechanism in open pit mines. Very few CFD studies have been published, especially the Large Eddy Simulation (LES), on the contaminant transport in deep open pit mines under arctic air inversion. The contaminant transport in an open pit mine under arctic inversion is due to a stable or nocturnal boundary layer in micro-meteorological terms. Understanding the physics of the stable boundary layer (SBL) is relevant to air flow and pollutant transport in deep open pit mines. This paper focuses on a Large Eddy Simulation (WMLES as Sub-Grid Scale Model) modeling of the SBL and pollutant transport in a large open pit mine.

Feb 23, 2014

By V

"Recent regulations, as well as a general aversion to central dust collectors within the Powder River Basin Coal user’s community, have created a need for an alternate method for eliminating airborne dust. This paper addresses the capital expenditure as well as the cost of ownership of an integrated point source air cleaning system in comparison to a central collection system. This assessment was conducted by comparing the cost to purchase and operate a central dust collection system and integrated air cleaner system on a typical multiple transfer point application. The central dust collector consists of a negative pressure blower, a series of filter bags, a collection hopper, a screw conveyor to place collected material back into the material stream, and a series of ducts to pull air and dust from individual pickup points. The point specific integrated air cleaners consists of a negative pressure blower to pull dust and air from an application point through a bag-less filter media located at the application point. The agglomerated material is then redeposited into the material stream at point of use without the need for ducting or a central material hopper. The assessment yielded a 54% reduction in capital expenditure and a 26% reduction in operating costs for the same application when using individual dust filters as opposed to a central system. In addition to the lowered cost, there are reductions in risk associated with the elimination of ductwork and the central containment enclosure for collected explosive dust. By the conclusion of this paper, the reader will have a better understanding of the quantifiable differences between a central dust collection system and a set integrated air cleaner systems. BACKGROUND Spillage has always been a problem in the bulk solids handling industry. As long as there have been conveyors, there has been spillage. Spillage is material that falls off a conveyor belt and creates a hazard in the environment around a conveyor belt."

Jan 1, 2016

By B. Birol, M. N. Saridede

"Slag density is a significant factor in determining the process efficiency of the electroslag remelting (ESR) process, where calcium fluoride (CaF2)-based slag is formed synthetically to refine metal ingots. Although there are some former studies investigating the density of CaF2-containing slags, the prediction models focusing on them are applicable only to some specific systems. The present study aims to build a model to predict density for a wide range of CaF2-containing ESR slags. To investigate density for various slag compositions, CaF2-Al2O3-based and CaF2-Al2O3-CaO-based slag compositions were prepared. Additionally, some minor constituents like FeO, MgO and MnO were added to a 5:3:2 CaF2-Al2O3-CaO slag in order to investigate the effects of these constituents on the slag. The volumes of the prepared slags were measured in a tube furnace at 1450-1550 °C using the sessile drop technique, and their densities were calculated. The results showed that for the slags, density is related to optical basicity, and therefore a prediction model based on an Arrhenius equation was built. The model was tested with data from literature, and its limitations and validity are discussed.IntroductionThe electroslag remelting (ESR) process is a refining method in which a metal ingot is remelted under a synthetic slag. These synthetic ESR slags are mainly composed of calcium fluoride (CaF2), calcium oxide (CaO) and aluminum oxide (Al2O3). Other constituents like iron oxide (FeO), magnesium oxide (MgO), manganese oxide (MnO) and chromium oxide (Cr2O3) are added to this system in relatively low amounts, according to the type of steel ingot to be refined. The prediction of slag properties, such as electrical conductivity, viscosity and density, is crucial for the selection of the synthetic slag in order to obtain the required process parameters, like temperature, the passing time of the molten metal droplet through the slag, and metal-slag separation (Akbari, Reitz and Friedrich, 2009; Hara and Ogino, 1981; Mattar, El-Faramawy and Fathy, 2002; Mehrabi, Rahimipour and Shokuhfar, 2005; Presoly, Korp and Schneider, 2008).As slag density affects metal-slag separation in the ESR process, predicting the density of an ESR slag is important for appropriate refining and improved product quality. Although there are many studies investigating the density of slags (Akbari, Reitz and Friedrich, 2009; Aune, Hayashi and Sridhar, 2005; Hara and Ogino, 1981; Matsushita, 2011; Mills and Keene, 1987, 1981; Seetharaman et al., 2013; Shu, 2007; Shu and Chou, 2013; Sikora and Zielinski, 1974; Xu et al., 2012; Zhang and Chou, 2010), the prediction models built are generally valid for oxide-containing slags (Aune, Hayashi and Sridhar, 2005; Bottinga and Weill, 1970; Mills and Keene, 1987; Seetharaman et al., 2013; Shu, 2007; Xu et al., 2012; Zhang and Chou, 2010). These models were built on either the molar volumes of the constituents (Bottinga and Weill, 1970; Mills and Keene, 1987) or the thermodynamically calculated enthalpy or free energy of mixing, which can be applied to a system containing constituents sharing an ion, such as an O- ion for oxide systems (Aune, Hayashi and Sridhar, 2005; Hillert, 1980; Persson et al., 2007). Some recent studies modeled the density of some oxide slags on their optical basicity (Shu, 2007; Shu and Chou, 2013; Xu et al., 2012; Zhang and Chou, 2010)."

Jan 1, 2016

By Sheshang Singh Chandel, Prvan Kumar Katiyar, Navneet Singh Randhawa, Prince Kumar Singh

Mineral process wastes, such as metallurgical slags nowadays, are of significant metals and materials resources in the circular economy. The usability of iron-making slag is well established; however, steel slag still needs to be utilized due to various physicochemical constraints. In this context, we have reviewed the global steel slag generation, processing, characteristics, and potential application with suggestions for futuristic possibilities to address the technical, economic, and environmental aspects of steel slag recycling. The steel slags inherit characteristics from ore chemistry and their processing routes, which may be Blast Furnace-Basic Oxygen Furnace (BF-BOF) or Direct Reduced Iron-Electric Arc Furnace (DRI-EAF) steel-making routes with/without treatment in a Ladle Furnace (LF). The average generation of slags in BOF, EAF, and LF processes accounts for 110 kg, 70 kg, and 40 kg per tonne of steel, respectively. Considering global steel production of 1878 million tonnes in 2020, the associated slag by-products possess a significant resource of major components like FeO, CaO, SiO2, Al2O3, etc. Selecting a recycling technique depends on the slag's end use, logistics, and physicochemical characteristics. BOF and EAF slag are used ~ 48% in road construction applications and ~ 10% for industrial specific metallurgical use. EAF slag is preferred as cementitious material as compared to BOF. Hot-stage modification of BOF slag has emerged as a preferred method to achieve desired chemical and subsequent mechanical properties for end use. BOF slag has high carbon dioxide sequestration potential for in-plant remediation among steel slags.

Nov 20, 2023

By Naoko Shimazaki, Andre Xavier

Over 10 million tourists have visited Vietnam in 2016. Travel and tourism accounted for 9.3% of the country’s Gross Domestic Product (GDP) in 2014. At the same time, as with many other resource-rich developing countries, Vietnam has been developing its extractive resources sector as a means of promoting the country’s social and economic development. In 2015, mining was the third largest contributor to GDP, and accounted for 8% of Vietnam’s gross domestic product. Vietnam is the third largest mineral producer in SE Asia. Although it produces zinc, nickel, bauxite, and manganese, coal mining is its most developed sector. The country has over two hundred coal mines, and total reserves of approximately 6 billion tons. Quang Nihn Province, where the World Heritage Site Ha Long Bay is located, is a very important tourism destination. It is also a coal-rich region where mining extraction and processing have been active since the early 20th century. Vietnam is signatory of the United Nations Sustainable Development Goals (SDGs). The country is aware of the importance and the challenges involved in managing the extractive sector in a way that does not undermine its tourism industry and yet that contributes to the country’s sustainable development. To this end Vietnam is taking actions towards implementing more advanced coal-mining extraction and processing techniques. The country is furthermore promoting a responsible mining sector, and is investing in programs that foster environmental protection and sustainable tourism. This paper examines the case of the Ha Long Bay region and the project involved in relocating the Hong Gai coal preparatory factory from a seafront area to a mountainside area. This paper provides a preliminary review of the initiatives adopted by the government of Vietnam to address the existing challenges that have resulted from a focus on promoting the country’s socio-economic development through the exploration of its rich coal endowment. Furthermore, it also describes Vietnam’s legal and policy frameworks. In conclusion this study identified that Vietnam has drafted a National Action Plan to implement the Sustainable Development Goals. The country is also taking an integrated approach to implementing the SDGs agenda and that it is assigning responsibility to a variety of ministries to achieve SDGs’ specific targets. Furthermore the country is changing policies and the legal framework in order to facilitating the execution of the work of agencies that are responsible for implementation, regulation and enforcement. In this respect, the approval of the National Action Plan on Sustainable Development Goals is another important step in that direction. While the decision of supplying its internal market with high quality coal helps minimize negative environmental impacts in Vietnam, exporting low quality coal to other countries does not help resolve the problem of CO2 emissions globally. With respect to the 2030 Agenda, this may be considered a temporary solution since to achieve the SDG goals, Vietnam will have to consider other sources of cleaner energy in order to align with the Sustainable Development Goals # 7 on affordable and clean energy.

Jan 1, 2017

By ANDREW HOBERT, Maoming Fan

Low-cost and environment-friendly green froth flotation modifiers of plant origin, such as guar gum, carboxymethyl cellulose (CMC), and starch, have been used in flotation of some sulfide and non-sulfide minerals. Certain green modifiers may be used as dispersants, flocculants, depressants, or activators. The functions of green modifiers in froth flotation highly depend on their molecular composition, flotation slurry chemistry, hydrodynamic conditions, etc. This paper will discuss the fundamentals, current applications, and potential new applications of guar gum, CMC, and corn starch in valuable minerals (phosphate, potash, and iron ores) and the unwanted gangue minerals (silica and clay minerals) flotation. In this study, improved flotation performance was achieved using some green modifiers in flotation columns with the more plug-flow environments than in conventional flotation cells approaching perfectly mixed conditions. This is because the hydrodynamic cavitation-generated ultrafine bubbles could help bridge ultrafine particles to form aggregates, promote the formation of flocs, and increase the stability of flocs.

Jan 6, 2022

By Y. Lahaye, O. Martinsson, B. I. Palsson

"Four main and three minor rare-earth-element (REE)-bearing minerals were identified and quantified in the Kiirunavaara apatite iron ore tailings using optical microscopy, an electron probe microanalyzer (EPMA) and a mineral liberation analyzer, and their chemical compositions were analyzed by the EPMA and laser ablation inductively coupled plasmamass spectrometry. REEs are shown to be contained in the minerals apatite, monazite, allanite, titanite, zircon, thorite and synchysite. In zircon, thorite and synchysite, they occurred in only trace amounts and contributed limited amounts to the total REE budget, and these are consequently of minor importance. Monazite occurred as inclusions in apatite and as free particles, 90 percent liberated. Allanite occurred to some degree in mixed grains with magnetite but also as free particles. Monazite mainly reported to the apatite concentrate, while allanite and titanite largely went to the tailings, the latter preferably to those fractions smaller than 38 µm. The amount of titanite in the finest tailings fraction was 2.3 weight percent, containing close to 1 percent REEs, with heavy rare earth elements (HREEs) making up 28 percent of the total REEs. However, a texturally distinct group of titanite grains showed an HREE/REE ratio of up to 67 percent. Furthermore, titanum dioxide analyses indicate that titanite is preferentially released into the tailings from the secondary magnetic separation step in the concentrator. Our data therefore suggest that titanite, occasionally enriched in HREEs, can be extracted from the processing stream and might thus be considered a new source for REEs at Kiirunavaara and similar deposits.IntroductionDeposits of apatite iron ores are the major source for iron in the European Union and are exploited by Luossavaara-Kiirunavaara AB (LKAB) in several mines in the Kiruna-Malmberget area in northern Sweden. Kiirunavaara is the largest of the apatite iron orebodies in Sweden, comprising more than 2 Gt of iron ore with 60 to 68 percent iron (Fe). At the end of 2015, the total accumulated production of crude ore from openpit and underground mining since the start of mining was 1,566 Mt, with ore reserves of 644 Mt grading 46.3 percent Fe (LKAB, 2016). The deposit defines a steeply dipping tabular body, approximately 6 km long and up to 180 m thick, extending at least 1,500 m below the surface. It is situated in the middle part of the Palaeoproterozoic Kiirunavaara Group of volcanic rocks and follows the contact between a thick pile of trachyandesitic lava and overlying pyroclastics (Martinsson, 2004)."

Jan 1, 2017

By Muhammad I. Kabir

The streamline method of recovery prediction reduces a two-dimensional problem to a bundle of one-dimensional ones. This paper presents the development and application of a novel scaling technique which, when used with a streamline model, causes s bundle of one-dimensional problems to further reduce to a single one-dimensional calculation. The one-dimensional calculation accounts for chemical-rock interactions and the streamline model for areal sweep. The scaling technique significantly reduces computation time, is readily modified to desk-top calculations, and can be applied to both absorbing and reacting species. The work was sponsored by the Interior Department's Bureau of Mines.

Jan 1, 1984

By Jian Zhou, Shuai Huang, Wenqin Xi, Kun Du

The deep oceans harbor a wide variety of mineral resources that are characterized by their abundance and high quality. Nations worldwide are actively pursuing the exploration and extraction of these resources. This paper provides a concise overview of the mineral resources found in the deep sea, highlighting the challenges associated with their exploitation. Furthermore, it presents a comprehensive analysis of the historical development of deep-sea mining technology and equipment, offering valuable insights into this field. By examining the current issues and obstacles faced in deep-sea mineral extraction, this study concludes that the future of deep-sea mining lies in the direction of automation, intelligence, and standardization. Additionally, it identifies the key technological advancements that need to be achieved in order to overcome the challenges associated with deep-sea mining.

Jan 5, 2024

By V. Dentoni

The paper deals with the assessment of the visual impact generated by surface mining and quarrying. Previous research works proved the applicability of an indirect method based on the elaboration of digital images through which the extent of the visible altered area and the chromatic contrast with the surrounding environment is calculated. The resulting level of visual impact allows an objective comparison among different cases as far as the evaluation procedure is univocally defined. The article illustrates the application of the method to a number of selected quarries located within the Sardinian territory; different issues are discussed such as the choice of the viewpoints from which the pictures are taken, the influence of the distance from the quarry to the selected viewpoints, the light condition and the orientation of the quarry faces. Moreover, the visual impact level obtained from pictures taken at the same time with five digital cameras are compared in order to evaluate the contribution on the overall uncertainty.

Jan 1, 2008

By N. Damiano, C. Zhou, B. Whisner, M. Reyes

"The industrial Internet of Things (IIoT)—a concept that combines sensor networks and control systems—has been employed in several industries to improve productivity and safety. NIOSH researchers are investigating IIoT applications to identify challenges of and potential solutions for transferability of IIoT from other industries to the mining industry. Specifically, NIOSH has reviewed existing sensors and communications network systems used in U.S. underground coal mines to determine whether they are capable of supporting IIoT systems. The results show that about 40% of the installed post-accident communication systems as of 2014 require minimal or no modification to support IIoT applications. NIOSH researchers also developed an IIoT monitoring and control prototype system based on low-cost microcontroller Wi-Fi boards, to detect a door opening on a refuge alternative, activate fans located inside the Pittsburgh Experimental Mine, and actuate an alarm beacon on the surface. The results of this feasibility study can be used to explore IIoT applications in underground coal mines based on existing communications and tracking infrastructure. INTRODUCTION The nation’s approach to health and safety in mining has historically been reactive in the sense that health and safety regulations and mandates have traditionally been passed as a result of tragic mining accidents. An example of this is the Mine Improvement and New Emergency Response Act (MINER Act) of 2006, which was passed as a result of several mining accidents where tracking of and communications with underground personnel were severely limited. While this reactive approach has led to the development and implementation of highly impactful safety interventions and safety practices, there currently exists a technological revolution that can shift the paradigm toward a proactive approach based on preventative methods: Internet of Things (IoT). IoT is the network of physical objects or ""things"" embedded with electronics, software, sensors, and connectivity to enable that network to achieve greater value and service by exchanging data with the manufacturer, operator, and/or other connected devices [1, 2]. It should be noted that IoT has been defined from various perspectives, and hence numerous definitions exist in the literature. The apparent ambiguity of the IoT definition might be due to the fact that IoT is syntactically composed of two terms: internet and things. The first one pushes towards a network-oriented vision, while the second tends to put the focus on generic objects. The traditional internet can be viewed as an internet of computers —i.e., “things” connected to the internet are computers only. IoT “extends” the internet by allowing other generic things that are commonly found in our daily life, such as refrigerators and cars, to be interconnected via the internet, and thus creates a bridge between the virtual word and the physical world."

Jan 1, 2017

By Rongjie Kong, Shiwei Wang, Dongjiao Gui

Metal cations have significant effects on the flotation of coal and minerals. In this study, the effects of monovalent cations ( Na+ and K+) on the flotation of low-rank coal (LRC) were investigated using flotation and particle–bubble attachment experiments and through X-ray photoelectron spectroscopy (XPS) and molecular dynamics simulations. Oleic acid (OA), methyl linoleate (ML), hexadecyltrimethylammonium chloride (CTAC), ricinoleic acid (RA), and kerosene were used as flotation collectors. The flotation experiments revealed that the flotation yields of LRC improved when OA, ML, RA, CTAC, and kerosene were used in pure deionized water. However, flotation was suppressed for these collectors in the presence of K+ and Na+ ions. In contrast, when using CTAC, the flotation yield increased in the presence of these ions. Specifically, the flotation yield increased from 41.24 to 87.03% when 2.0 kg/t CTAC was used in 10 mmol/L NaCl solution. Particle–bubble adhesion experiments and XPS revealed that the hydrophilic groups of CTAC were adsorbed on the LRC surfaces by electrostatic forces, whereas the oxygen-containing functional groups of OA, ML, and RA formed hydrogen bonds with the LRC surface in pure water. Finally, the simulating result revealed that the hydrophobic ends of the OA, ML, and RA collectors hinder the flotation of LRC by adsorbing monovalent cations, whereas the adsorption of monovalent cations on the hydrophobic end of the cationic surfactant (CTAC) promotes flotation via strong electrostatic interactions.

Jan 31, 2024

By J. Evans

INTRODUCTION Section 209(b) of the Federal Land Policy And Management Act of 1976 (FLPMA-43 U.S.C. 1719 b) authorizes the Secretary of the Interior to convey mineral interests owned by the United States where the surface is or will be in non-Federal ownership. The objective is to allow consolidation of surface and subsurface (mineral) ownership. Certain major conditions must prevail for a conveyance to occur. These are: 1) There are no known mineral values (KMV) or 2) Where the mineral reservation interferes with or precludes appropriate non-mineral surface development and that non-mineral development is a more beneficial use of the land than the mineral development. Remember that allegation, hypothesis or speculation that the conditions could or may exist in the future will not be a sufficient basis for conveyance. Convincing factual evidence for an applicant’s case for mineral conveyance must be made in order to achieve that conveyance. See 43 CFR 2720 0-1 to 0-3, and 0-6. CONCEPT OF KNOWN MINERAL VALUES Known mineral values means mineral rights in lands containing geologic formations that are valuable in the monetary sense for exploring, developing, or producing natural mineral deposits. The presence of such mineral deposits with potential for mineral development may be known because of previous exploration, or may be inferred based on geologic information (43-CFR 2720.0-5(b).

Jan 1, 2007

By Henry J. Schwellenbach

The New York Trap Rock Corporation has four plants located along the Hudson River, all within 70 miles of New York City. The company produces crushed stone for use as construction aggregate, with a total annual production amounting to 6 million tons. The crushed stone is moved to markets in metropolitan New York, New Jersey and Long island areas by water transportation. There are daily deliveries of approximately 35 scowloads to the market area. Its customers are contractors with ready-mixed concrete and asphalt plants located on the water, where the aggregate is unloaded for its ultimate use. For a number of years capital equipment was replaced only when the current operating machinery was no longer serviceable, or when' a need was apparent for a different type of equipment. There was no particular regard for efficiency or for operating and maintenance costs. Such lack of system often resulted in the emergency purchase of equipment which was later found to be unsuitable for the job. A few years ago it became apparent that a systematic procedure was necessary. After evaluation of several systems, an individualized plan was evolved from the basic pattern developed by the Machinery and Allied Products Institute. The system adopted by New York Trap Rock has proved wholly satisfactory.

Jan 1, 1959