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By H. Abdollahi

Cold rolling is one of the most important techniques in metal forming since the cold rolling products are almost finished product, The product quality of this process is widely influenced by friction in the roll gap; therefore, controlling the friction and other parameters affecting the cold rolling is very important in order to have a product with high quality, Among the cold rolling parameters, the pressure distribution or friction hill within the roll gap is known as the most significant one, In this study, a new software (Matroll), is introduced which can determine the coefficient of friction (COF) and plot the friction hills for an industrial mill, Besides, based on rolling equations, it offers about 25 rolling parameters as outputs. To verify the software operation, the real industrial rolling data was used as inputs, The results (outputs) are in good agreements with the findings of other researchers, The COF values are very reasonable, The friction hill shows that COF is not constant over the whole arc of contact.

Jan 1, 2005

By D. D. Campbell

The Hat Creek coal deposit s occur within folded and faulted Tertiary (Eocene) strata of the Coldwater Group, which comprises weakly lithified shales, siltstones and conglomerates underlying the floor and lower flanks of the valley of Upper Hat Cr eek . This upland valley,16 miles in length and 2-4 miles in width, is located within the eastern foothills of the Coast Mountains, 120 miles northeast of Vancouver, approximately midway between the towns of Lillooet and Ashcroft, in the Interior Dry Belt of British Columbia . Most of the valley floor is covered by till and glacial outwash deposits ranging up to 500 feet in depth. Became of this overburden cover , the majority of the data on the coal deposit have been obtained from diamond drilling done during 1974?76 by the property owner, B .C. Hydro and Power Authority. Because of the limitations imposed by the lack of out crop, the Tertiary geology at Upper Hat Creek is imperfectly known; however, it appears from correlation with other coal-bearing Tertiary remnants in the southern interior of the province that these remnants, including Upper Hat Creek, may represent preserved segments of the western shoreline of a Tertiary continental sea along which deltaic swamps developed and were sustained for unusually long stable periods, giving rise to the world's thickest known coal beds.

Jan 1, 1977

By S. S. Al-Thyabat, A. M. Ghrair

"Printed circuit board (PCB) is the main part of any electric or electronic device, providing mechanical support and electric connection for the board eclectic components such as capacitors, resistors, diodes etc. PCB consists of non-conductive substrate overlaid with one or more layers of copper sheets. They also contain appreciable amounts of base metals (copper, nickel, tine, and aluminum) and precious metals (gold, silver, and rare earth elements (REE)) which end up in the landfill at the PCB end-of-life.PCB recycling E-waste in general is a profitable business; many valuable raw materials, precious and base metals, can be extracted with high purity. Approximately, one metric tonne of PCBs may contain 80-1500 g of gold and 160–210 kg of copper. The precious metals recovered from PCBs occur at concentrations higher than commercially mined minerals. Also PCB recycling is very important to our environment since many heavy metals (e.g. lead) may be leached from the landfills to the underground reservoirs. In Jordan, however, the work conducted on E-waste and PCB recycling in particular is limited; currently most of the E-waste is either exported or dumped in the landfill.In this work, a combination of physical (magnetic separation), physicochemical (flotation), and chemical methods (leaching) were used to compare metals concentrations in leach liquors produced from a concentrates resulted from a combination of these methods. It was found the leach liquor of the magnetic fraction of the PCB coarse size gave the highest concentration of Fe, Al, and Ni while concentration of Cu was higher in leach liquor of nonmagnetic sink fraction. On the other hand, metals concentration almost similar for both sink and float of the fine size fractions, indicating even distribution of metals concentrations in the fine size fractions."

Jan 1, 2016

The following briefing is intended to provide an overview of the present and future challenges associated with our access to a secure and adequate supply of electrical energy necessary to support safe, productive and sustainable mining initiatives at Musselwhite. Contents ??Site power demand vs. current available supply ??Supply technical deficiencies ?adequacy and security of present supply ??Present internal generation ??Anticipated future internal generation requirements ??Increased requirements necessary for planned expansion ?demand/security ??Goldcorp?s strategy to achieve required supply ?transmission line initiative ??Subsequent benefits to others from the Goldcorp initiative. ??Economic impact of MusselwhiteMine on the northwest region ??Anticipated economic impact of planned expansion ??Expected life cycle of MusselwhiteMine ??Comparative energy costs for similar operations in other jurisdictions ??Conclusions ??Anticipated action plan ??Energy Management Initiatives ??Site Orientation

May 1, 2009

By Getu F. Biftu

There is general agreement among scientists that global surface temperatures have been increasing during the past decades. The increase in temperature is postulated to be the result of either an increase in greenhouse gases emission or climate variability (i.e., due to variations in sun or volcanic activity or El Nino and La Nina events) during past decades and may continue to increase. The effects of a predicted rise in the Earth?s surface temperature include an increase in average global evaporation and increase or decrease in precipitation (Bloomfield, 1992; Mann et al., 1991; Vinnikov et al., 1990; Gan 1995; Zhang et al., 2000a). The general circulation models (GCMs) project a global warming due to greenhouse effects of 1.5-4.5°C by the mid 2050s, with the most pronounced changes taking place in northern latitudes (Nicholls et al., 1996). However, similar predictions at a watershed scale or even a regional scale using GCMs are mot possible yet (Arnell et. al., 1996; Georgievskii et. al., 1996; Zhang et al., 2000a). Detection of historic trends, changes and variability in climatic variables is another indirect means of understanding potential future changes or variability at regional and local scales. The main objective of this paper is to review studies related to climatic change or variability and associated hydrologic changes at a regional scale and local scale, particularly those studies applicable to the Oil Sands Region (OSR) of Alberta. This paper identifies gaps in our current understanding of the hydrologic processes that may be affected by climate change; it discusses potential implications to developments in the OSR; and it explores mitigation opportunities including several that have already been implemented.

May 1, 2004

By S. P. Lowe

Flotation testing of Flin Flon ore was started in the Denver laboratory of Complex Ores Recoveries Co. in March, 1926. There had been a considerable amount of flotation testing previously which had shown possibilities of success, and it was felt that, with the increased knowledge of flotation and the comparatively new reagents then available, flotation held out the best prospects for a successful commercial treatment of this ore. There remained available for this experimental work a small amount of the rejects from a thorough sampling of the mine and some ore from the mine dump.

Jan 1, 1930

By K. Ilankoon, I. M. Saman, S. J. Neethling

In heap leaching the transport of the acid from the drippers to the surface of the ore particles is a major factor in the overall performance of a heap. This flow behaviour is complex as the flow is unsaturated and occurs along a tortuous set of inter-particle channels and connections. The particle properties such as size, shape and porosity are very important when modelling the liquid holdup and flow within heaps, since the dominant mechanisms at work are quite different. This paper investigates the effect of these particle properties experimentally on heap flow behaviour using a 1-D column leaching system consisting of non-porous glass beads with a system of actual ore particles. The similarities and differences between the two systems on flow behaviour are described using an inter-particle flow model. In addition, the applicability of positron emission particle tracking (PEPT) for laboratory column leaching will be detailed to calculate hydrodynamic dispersion in packed beds compared to more conventional residence time distribution (RTD) tests and also to obtain the time averaged rivulet flow paths through the particles of the bed for the better understanding of heap hydrodynamics.

Jan 1, 2014

By The Hollinger Mill Staff

ALTHOUGH cylindrical grinding mills have long been used, there is wide divergence of opinion as to what constitute best operating conditions. Questions such as mill diameter, diameter-length ratio, revolutions per minute, type and size of grinding media, volume of charge, circulating load, pulp level, pulp consistency, liner design, and size of feed, have all been given serious consideration by competent scientific investigators as well as by operators. While many laboratory and plant tests have been made that would seem to justify certain definite conclusions, there is a dearth of definite data giving actual results obtained when a grinding mill working between fixed limits is operated at its maximum capacity under varying conditions as to ball load, circulating load, speed, etc. In tests conducted recently at the Hollinger, extending over a period of thirteen months, to determine the best operating conditions for a ball-mill 6 ft. 6 in. diameter inside the liners, some very interesting facts have been ascertained. This paper is presented in the desire to make public the results of these tests and not with the idea that the last word has been spoken in regard to grinding. We feel, however, that these facts justify certain definite conclusions and hope that, by the fullest and frankest criticism and discussion, the essentials necessary for the correct design and operation of grinding mills will become better known.

Jan 1, 1937

By T. A. Chepushtanova, I. U. Motovilov, V. A. Luganov, G. D. Guseynova

"Kazakhstan has significant reserves of oxidized nickel ore with low nickel content. Processing of such ores is effective via pyrometallurgical technologies such as smelting to ferronickel or matte with consecutive extraction of metals from melting products. There are also many options for direct hydrometallurgical processing. However, they do not provide high nickel recovery.We studied extraction of nickel and cobalt by using combined technology of low-grade ore processing from the Shevchenko Kazakhstan deposit, which includes smelting to poor matte followed by hydrometallurgical processing of the matte. The nickel content in the initial ore was 0.75–0.9%. Pyrite concentrate of Sokolov-Sarybai Kazakhstan deposit containing 0.17% cobalt and 0.06% nickel had been used as a sulphidizer at smelting.As a result of the study, we were able to extract up to 98% of the nickel and up to 80% of the available cobalt. Obtained matte contained 3.1% nickel, 0.29% cobalt, 71.6% iron and 24.3% sulfur. Matte leaching was carried out by hydrochloric acid. The iron content in the pregnant solution was 170–185 g/dm3. Nickel and cobalt precipitation from the pregnant solution was carried out by hydrogen sulfide. Initial matte or cast iron was used as neutralizers during the process. Practically complete precipitation of nickel was achieved at 3–5% excess of neutralizer at 333–343°K in 4 hours; up to 95% of cobalt precipitation was achieved in 50% excess of neutralizer at 363°K in 8 hours. The purified solution contained 200–600 mg/dm3 of nickel, 80-100 mg/dm3of cobalt and 175–185 g/dm3 of iron. The purified solution allows to obtain iron oxides by high-temperature hydrolysis, and to regenerate hydrochloric acid.As a result of non-ferrous metals precipitation we obtained sulfide concentrate with concentration of Ni up to 25% and concentration of Co up to 5.5%. The technology is recommended for semi-industrial testing."

Jan 1, 2016

By Niraj Bala

Boiler tubes of coal-fired boilers suffer severe erosion-corrosion (E-C). One method to counteract this problem is by the use of therma, spray protective coatings. Cold spray coating process was used to deposit Ni-20Cr powder on SA 516 (Grade 70) boiler steel. The bare as wel, as the coated steels were subjected to cyclic experimenta, studies, in the superheater zone of a coa, fired boiler. The weight change technique was used to establish kinetics of the erosion-corrosion. XRD, FE-SEM/EDS and X-ray mapping techniques were used to analyse the as-sprayed and corroded specimens.

Jan 1, 2010

By Masaharu Moteki

At present, the Unmanned Construction System (UCS) is adapted on initial operation against the disaster. For instance, it has been used in Unzen. When the scale of the disaster is big, or the danger to a person is big, the UCS is expected as a quick and safe construction technology. The Remote Controlled UCS is introduced into construction site to repair earth-fill embankment or to remove rock, as urgent measures after the disaster outbreak. For improvement of the operability, shortening of the skill time, reduction of the fatigue, examination of the most suitable system (placement of a monitor and the joy stick) of the remote system is a main theme in the Public Works Research Institute (PWRI). In the report of this year, when the operator controls construction machine directly or he controls it using remote system (he can check the situation of site only via monitor), the degree of achievement, construction efficiency and construction precision were inspected. The remote system which is based on the system used at Unzen was developed at PWRI.

Aug 1, 2013

By Michel Dagbert, Mohammed Harfi

"Abstract - The Draa Sfar polymetallic deposit, at about 16 km NW of Marrakech in Morocco, is a massive sulfide zone at the contact between an underlying volcanic and an overlying clastics sequence. The mineralized body is a flat lens with schistosity and "boudinage," tilted to the west and with a strong dip to the east. The lens extends over a strike length of about 2 km and from surface to a depth of about 1 km, with thickness varying from 1 m to almost 30 m. It has been intersected by about one hundred surface drill holes and, in its south part, by about thirty underground fan holes from two exploration levels at depths of 300 m and 400 m. On these two levels, the massive sulfide zone has been channel sampled over a cumulative length of about 0.7 km. Results from drill and channel samples are used to estimate the resources of the orebody according to several methods: sections, polygons around intercepts on a longitudinal plan, grids on the same longitudinal plan with various distance weighting methods including kriging and, finally, a 3D grid with the same range of interpolators. A comparison of the various estimates delineates the important factors in deriving resources for this type of deposit. Those factors are mostly geological and related to the interpretation of the geometry of the two limiting surfaces of the zone. For the 3D gridding, the authors have devised a new and original method that constrains the interpolation of blocks from samples to a geometry of limiting surfaces. The resulting model shows internal grade variations that parallel fluctuations of zone thickness and orientation without having to re-orientate the search window in each block. Résumé - Le gisement polymétallique de Draa Sfar, situé à environ 16 km au NW de Marrakech est un horizon de sulfure massif au contact d’une formation volcano-sédimentaire de base et d’une formation détritique sur-jacente. Le corps minéralisé se présente sous forme d’une méga-lentille aplatie, schistosée, boudinée et déversée vers l’ouest avec un fort pendage vers l’est s’étendant sur une longueur de 2 km et une profondeur de près de 1 km avec une épaisseur variant de moins d’un mètre à près de 30 m. Il a été reconnu par plus d’une centaine de sondages de surface et, dans sa partie sud, par une trentaine de trous souterrains en éventail à partir de deux niveaux à des profondeurs respectives de 300 m et 400 m. Sur ces mêmes niveaux, des traçages ont permis de rainurer le minerai sur une longueur cumulée de 0.7 km. Les données de sondage et de rainurage ont servi à estimer les ressources du gisement selon plusieurs méthodes : sections, polygones sur longitudinale, grille sur longitudinale avec différentes pondérations en fonction des distances incluant le krigeage et enfin grille tridimensionnelle avec le même éventail de pondérateurs. La comparaison des estimés obtenus permet de mettre en évidence les facteurs importants dans l’estimation des ressources de ce type de gisement. Ces facteurs sont essentiellement géologiques et relatifs à l’interprétation de la géométrie des limites des corps minéralisés. Pour l’estimation sur grille tridimensionnelle, on a mis au point une technique originale qui calque l’interpolation des blocs à partir des échantillons sur cette géométrie des surfaces de contact. Le modèle résultant montre des variations internes de teneurs qui épousent les fluctuations d’épaisseur et d’orientation de la zone sans qu’il soit nécessaire de ré-orienter les fenêtres de recherche dans chaque bloc."

Jan 1, 2002

By H. J. McQueen

The irregular history of Mg wrought products is briefly described. The temperature and strain rate dependence of microstructural evolution, flow stress and ductility of Mg alloys in hot working, are described. The flow curves rose rapidly to a peak stress which was lower as temperature T rose and strain rate e declined and above 300°C the curves extended into plateaus until failure. Clearly grains not oriented for slip undergo mechanical twinning in the initial stages (a 0.15) at all temperatures. Basal slip proceeds in suitable grains and in the twins. The stress concentrations at grain and twin boundaries lead to slip on non-basal systems and to the formation of subgrains with greater dynamic recovery (DRV) at higher T or lower e. With increasing strain, misorientation builds up resulting in dynamic recrystallization (DRX) first at twin intersections and later at grain boundaries which have become quite serrated. Even after extensive straining at high temperatures, the new grains are found mainly along the boundaries of the original grains, leaving their centers with only basal slip except when nucleation at twins leads to completion of DRX throughout a grain. Despite similar shear modulus and melting point to Al, hot mechanical forming behavior of Mg alloys differ due to differences in crystal slip systems, twinning, and second phases. Moreover, the influences on forming of alloy additions (solutes, segregation in casting, dispersoids, precipitation) and impurities are not as well catalogued as for Al. Despite the benefits from dynamic recrystallization, varied grain orientation effects, heterogeneous substructures and the resulting stress concentrations result in considerably lower ductility for Mg alloys at the same stress level as for Al materials. Application of these theories to extrusion, rolling and forging and the effects on product properties are surveyed.

Jan 1, 2006

By Laxman M. Amaratunga

Laboratocy flarmnability tests were perfonned on dust samples from Fraser Mine in a 1.2 L Lindenburg horizontal tube furnace to detennine the percentage of sulphur oxidized during ignition. The explosion pot ential of sulphide dusts depends on their degree of spontaneous oxidat ion, which was measured by the quantitative analysis of so2 gas released during ignition. Test results indicated that dusts with low sulphur content could exhibit a higher degree of oxidation than a sample with high sulphur content. txlst characterisation using image analysis techniques suggests that the structure and the texture of dust are important factors influencing the explosibility of sulphide dust at ignition temperatures. Therefore for safe mine operations% sulphur content cannot be considered as a reliable single index that could be used to predict the potential of a sulphide dust explosion. Physical, chemical and mineralogical characterisation of dust plays an important role in the detennination of suitable indices for the prediction and prevention of sulphide ore dust explosions.

May 11, 1988

By H. Karakul

Determination of P-wave velocity (Vp), which is closely related to intact rock, is a nondestructive, easy and less complicated procedure. Due to these advantages, there is an increasing trend to predict the geomechanical properties of rocks from Vp. In addition to mineral content, cementing material and porosity, degree of saturation (Sr) are also other factors influencing geomechanical properties of the intact rock. However, up to the present, in the studies on the prediction of geomechanical properties of rocks from Vp, the effect of Sr has not been investigated. By considering this issue, in this study, it was aimed to correlate strength properties (uniaxial compressive and tensile strengths) and Young’s modulus with Vp of various rock types under different degrees of saturation. In addition, geomechanical properties of rocks were estimated from theoretical P- and S-wave (Vs) velocities, which were calculated based on their mineralogical compositions. For this purpose, fourteen different rock types were collected from several parts of Turkey and a comprehensive laboratory testing program was conducted. In the statistical analyzes, a series of different prediction relationships were developed by using independent variables such as Vp, Sr and effective clay content (ECC). Simple regression analysis results indicated that although prediction of the geomechanical properties of rocks from Vp at different degrees of saturation was possible, the equations developed would yield some under- or over-predictions. On the other hand, the multivariate equations developed have very high prediction performances and are very useful tools to estimate the geomechanical properties from the measured Vp at any Sr value. In addition to mineralogy, the variation in geomechanical properties with increasing Sr is also associated with the combined effect of porosity and clay content, which is first described in this study by the term Effective Clay Content (ECC). It is also noted that strength properties of rocks at any Sr may also be estimated using the empirical relations based on the theoretical Vp and shear-wave velocity (Vs) values, which are calculated from their mineralogical compositions.

Jan 1, 2015

By Mahmood Alemrajabi, Ake Rasmuson, Kerstin Forsberg, Kivanc Korkmaz

"In the present study, the recovery of rare earth elements (REE) in the nitrophosphate process of fertilizer production is investigated. The apatite has been recovered from iron ore tailings by flotation. After digestion of apatite in concentrated nitric acid, Ca(NO3)2.4H2O is first separated by cooling crystallization and then the REEs are recovered by precipitation. Optimum conditions in these steps have been determined in a previous study. The precipitate mainly consists of CaHPO4.2H2O and REE phosphates.In the present study, selective dissolution and re-precipitation have been studied in order to obtain a precipitate that is more concentrated in REEs. The precipitate was selectively dissolved in nitric and phosphoric acid at different acidities (pH 6 to 0) with the liquid /solid ratio of 100 mL/g. It is shown that most of the CaHPO4.2H2O and other calcium containing compounds will be dissolved at pH 2 while the REE phosphates are not dissolved above a pH of approximately 2. Thus, by partial dissolution of the REE precipitate at pH 2.5 most of the solid calcium phosphates will be dissolved and the remaining solid phase, which is more concentrated in REEs, can be filtered off as a fairly concentrated REE solid mass and the liquor can be recycled back to recover more P nutrients. Alternatively, the REE enriched precipitate was dissolved completely in nitric acid and re-precipitated again by addition of ammonium hydroxide to pH 1.2. A chemical equilibrium software, MEDUSA (Puigdomenech, 2013) has been used to evaluate the experimental results and to estimate the optimum conditions for selectively dissolving the precipitate."

Jan 1, 2016

By O. G. Olvera, L. S. Quiroz-Castillo, P. J. Valenzuela-Guerrero, D. G. Dixon

The effect of sulfuric acid concentration on the extractions of arsenic and copper in the catalyzed batch leaching of an enargite concentrate was studied. The acid concentrations studied were 60, 45, 30 and 15 g/L. The experimental series yields maximum copper extractions of 96 to 98% in an interval of 81 - 185 h leaching time for 60 - 15 g/L initial sulfuric acid concentration; all the copper extractions plateaued after these values; the rates and plateaus of copper extraction are increased with higher acid concentrations. Arsenic extractions reached maximum values of 89% in 57 hours, 57% in 49 hours, 33% in 25 hours, and 25% in 112 hours respectively; these maximum values were followed by a steep decrease in arsenic concentration, which indicates a precipitation event occurs in the process. According to the literature and process conditions, the arsenic precipitates obtained are iron arsenates similar to scorodite. The stability of the residues was tested using the Toxicity Characteristic Leaching Procedure (TCLP) from EPA; the residues for the four concentration levels passed the TCLP test, reporting arsenic leaching values below 1 mg/L.

Jan 1, 2014

By A. L. Mackie

Mine water from base metal mines is generally characterized as having high concentrations of heavy metals and low pH, resulting in the need for treatment prior to discharge to receiving waters. In this study, two high-rate clarification processes were evaluated at bench-scale: the high density sludge (HDS) process and sand-ballasted flocculation. High-rate clarification processes generate larger, denser flocs which settle more quickly than those formed in conventional flocculation processes. The HDS process uses recirculated sludge in order to seed floc formation, whereas ballasted flocculation uses microsand. Both of these high-rate processes require the addition of quicklime or hydrated lime to increase pH and allow for the formation of insoluble metal hydroxides, which can then be removed in the clarification stage. Previous research has shown that cement kiln dust (CKD) can effectively replace quicklime in conventional sedimentation processes for metals and acidity reduction to meet discharge guidelines (Mackie & Walsh 2012). CKD is an alkaline by-product of cement manufacture that has fine particle sizes and varying free lime concentrations depending on the manufacturing process. The lower solubility (i.e., free lime content) of CKD requires larger doses of material to be added to reach treatment pH targets for metals precipitation. The purpose of this study was to evaluate the treatment efficacy of high-rate clarification processes for mine water treatment, compared with conventional sedimentation, at bench-scale with conventional (i.e., lime) and novel (i.e., CKD) pH adjustment additives. Results of the study showed that all treatment processes (i.e., HDS, ballasted flocculation, and conventional sedimentation) were able to reduce target metal concentrations to well below Canadian guidelines (i.e., total zinc and total nickel < 0.5 mg/L, total copper < 0.3 mg/L) using either CKD or lime. Additionally, mine water samples treated with CKD generated lower sludge volumes than those treated with lime (i.e., 50 versus 100 mL for conventional sedimentation and 100 versus 200 mL for HDS) even with increased concentrations of solids introduced during treatment. This is most likely due to slower neutralization rates when using CKD, due to its lower solubility, as well as finer particle size. The sand-ballasted flocculation process was able to reduce final turbidity in CKD-treated samples while the HDS process did not when compared to conventional sedimentation, making the ballasted flocculation process preferable for reducing final solids concentrations in CKD-treated mine water.

Aug 1, 2013

By F. Y. Hsiao, H. C. Kao

Underground excavation in hard rock is normally stable at shallow depth except for wedge failure. However, the excavation depth is rapidly increasing recently. In high overburden stress condition, the integrity of rock would be destroyed with degrading rock strength. Therefore, understanding both the peak and the post-peak strengths of hard rock are necessary to assess the tunnel stability at depths. The characteristic of the post-peak strength is seldom studied in Taiwan in the past. Various estimation methods for the post-peak strength degradation were briefly reviewed in the paper. Based on the Geological Strength Index (GSI) system is widely used in the determination of the rock mass strength, the quantitative residual GSI system was adopted to estimate the possible strength degradation for a hydraulic tunnel in Taiwan. The Mohr-Coulomb model (no strength degradation) and the post-peak strength degradation model (strain softening model) were used to simulate the excavation of the case tunnel at different depths. The analyses demonstrate that the tunnel is in stable condition at 600m of depth. And the effect of the postpeak strength degradation on tunnel deformation is progressively significant with increasing tunnel depth. Approximate 3-5 times of increase in crown settlement and horizontal convergence would occur when post-peak strength degradation are considered at 2400m of depth. Severe tunnel deformation may endanger the tunnel stability. Modeling results reveal that the post-peak strength degradation has a great effect on tunnel stability under high overburden stress condition, which should not neglect in deep tunnel design.

Jan 1, 2015

By H. Son

The three-dimensional (3D) reconstruction of as-built industrial plant models plays an important role in revamping planning, maintenance planning, and preparation for dismantling during the lifecycle of industrial plants. Recently, the 3D reconstruction of existing industrial plants was conducted using laserscan data to make surveying processes more efficient. However, the current 3D reconstruction process from laser-scan data is still limited due to the need for significant human assistance. Although a great deal of effort has been made to efficiently reconstruct 3D as-built industrial plant models, the presence of objects?such as equipment, pipelines, and valves of different sizes and shapes?in existing industrial plants significantly increases the complexity of laser-scan data and makes automating the reconstruction process more challenging in practice. The purpose of this study is to propose a knowledge-based approach for the 3D reconstruction of as-built industrial plant models from unstructured laser-scan data. First, pipelines were extracted from laser-scan data based on surface curvature information and knowledge about pipelines&apos; sizes from existing piping and instrumentation diagrams (P&ID). Once entire pipelines were extracted, they were modeled based on skeleton features. Then, the remaining objects were clustered and grouped separately via the region grouping process. Afterward, clustered objects were retrieved and modeled based on global feature-based matching from the 3D database. Finally, the resulting model was checked to ensure that it was well-reconstructed according to the information regarding the relationships among objects abstracted from the existing P&ID. The preliminary results on actual industrial plants show that integrating knowledge into the reconstruction steps played an important role in the proposed approach and that this approach obtained accurate as-built industrial plant models from unstructured laser-scan data. The proposed approach could be successfully utilized to assist in many applications during the lifecycle of industrial plants.

Aug 1, 2013