Rapportens syfte är att undersöka vilka störningar skrot från kamstålsbultar medför i LKAB:sunderjordsgruva i Kiruna. Vidare undersöks om det finns alternativa bultar eller tillvägagångssätt somuppfyller LKAB:s krav för bultning av tvärortar. En statistisk analys görs på hur mycket och i vilketområde skrotet kommer upp till sovringens 14 skrotband. Alternativbultarna ska inte vara magnetiskaoch om möjligt pulveriseras vid sprängning. Det ska även tas upp om det är ekonomiskt försvarbart attbyta till alternativa bultar. Bergförstärkningen i tvärortarna består till största del av kamstålsbultar ochsprutbetong. I tvärortarna anses risken för seismisk aktivitet vara låg och därför behöver intebergbultar som dimensionerats för dynamiska laster användas. Den bulten som används i dag är denså kallade Kirunabulten som är en kamstålsbult med en kil längst in. Bergbultarna tros orsaka problemi fasta anläggningar genom att t.ex. bulten sticker ut från vagnarna under jord och tar i nödstoppslinoretc. Ovan jord kan bulten orsaka skada på transportband samt förorsaka stockningar i stup och fickor.Åren 1979- 1981 utfördes ett antal försök med de då nya glasfiberbultarna. Det sattes ett hundratalbultar i Kirunagruvan. Problemet då vara att glasfiberbulten hade en för glatt yta och inte kunde fästasi berget tillräckligt bra. Idag är glasfiberbulten en väl testad bult och används flitigt ute i världen.Jämfört med Kirunabulten har glasfiberbulten runt 30 % högre draghållfasthet, 40 % lägreskjuvhållfasthet men är 70 % lättare. En litteraturstudie har genomförts för att ta reda på mer om LKABoch vilka olika typer av bultar det finns samt vilka tester som är genomförda. Insamling av rådata hargjorts från gruvan och verken ovan jord för vidare beräkningar. En undersökning av vad det finns förmaterial och leverantörer på marknaden samt en jämförelse av olika bultar mot LKAB:s standard hargjorts. Gruvan har problem med bultar som stör processen genom oförutsedda stopp i flödet. Det blirdäremot inga större produktionsbortfall p.g.a. bultar som följer med i produktionen. Det är inte säkertatt ett byte till glasfiberbultar skulle hjälpa då det finns risk att även denna bult följer med malmen ochsticker ut från vagnar med mera, samt att den skulle tas om hand först i sovringen. Sovringen har enså pass stor överkapacitet på anläggningen att den klarar allt som gruvan skickar upp i dagsläget.Antalet bult kommer att öka för nu krävs systembultning. Problem orsakade av att bulten följer skrotetär ganska konstant sett över ett år. Antalet skrot per ton är relativt konstant även om antalet skrotökar över tiden. Sett över en vecka visar att skrotflödet kommer med jämnt flöde upp till sovringens14 skrotband. Medianens snitt ligger på 12,5 skrot sett över en vecka. Tidsmässigt ligger under sammaperiod ståtidens medianen i snitt 0,84 tim. Hela anläggningen från gruvan under jord till anrikningsverket störs inte nämnvärt idag av skrotet och ett byte till några andra bultar kan inte motiveras. Vissaförluster blir det trots allt i gruvan men dessa kan inte avhjälpas med andra typer av bultar.Rekommenderas att vidare studier genomförs med glasfiberbulten för att se hur denna beter sig iflödet. / The purpose of this report is to investigate what disturbances scrap from rebar steel bolts causes inLKAB's underground Kiruna mine. Furthermore, it is investigated whether there are alternative boltsor approaches that meet LKAB's requirements for bolting of cross-cuts. A statistical analysis is made ofhow much and in which area the scrap reaches the 14 scrap belts in the sorting plant. The alternativebolts must not be magnetic and, if possible, should pulverized during explosion. It must also beaddressed whether it is economically justifiable to switch to alternative bolts. The rock reinforcementin the cross-cuts consists mostly of rebar steel bolts and shotcrete. In the cross-cuts, the risk of seismicactivity is considered to be low and therefore rock bolts dimensioned for dynamic loads do not needto be used. The bolt used today is the so-called Kirunabulten which is a rebar steel bolt with a wedgeat the inside end. It is believed that the rock bolts cause problems in the process. A rock bolt that windsup in the train wagon can cause problems by taking down the train electrical wires and emergencystop cables. Above ground in the sorting- and concentrating plants the bolts can cleave conveyor belts.The costs caused by the bolts are mostly underground on the train and crushing level. In the years1979-1981, a number of experiments were performed with the then new fiberglass bolts. About ahundred bolts were installed in the Kiruna mine. The problem at the time was that the fiberglass bolthad a too smooth surface and could not be attached to the grout sufficiently. Today, the fiberglass boltis a well-tested bolt and is commonly used in the world. Compared to the Kiruna bolt, the fiberglassbolt has around 30% higher tensile strength, 40% lower shear strength but is 70% lighter. A literaturestudy has been carried out to find out more about LKAB and what different types of bolts there areand what tests have been carried out. Collection of raw data has been done from the mine and theplants above ground for further calculations. A study of what materials and suppliers are on the marketas well as a comparison of different bolts against LKAB's standard has been made. The mine hasproblems with bolts that disrupt the process through unforeseen stops in the flow. On the other hand,there will be no major production losses due to bolts included in the production. It is not certain thata change to fiberglass bolts would help as there is a risk that this bolt also accompanies the ore andi.e. winds up in the train wagon, and that it would be taken care of first in the sorting plant. The sortingplant has such a large overcapacity that it can handle everything that the mine hoists at present. Thenumber of bolts will increase because systematic bolting is now required. Problems caused by the boltfollowing the scrap are fairly constant over a year. The number of scrap per ton is relatively constanteven if the number of scrap increases over time. Seen over a week the scrap flow is even up to thesorting plat’s 14 scrap bands. The median average is 12.5 scrap seen over a week. In terms of time, themedian stop time averages 0.84 hours during the same period. The entire facility from theunderground mine to the concentrator is not significantly disturbed today by the scrap and a changeto any other bolts can not be justified. After all, there will be some losses in the mine, but these cannotbe remedied with other types of bolts. It is recommended that further studies be carried out with thefiberglass bolt to see how it behaves in the production.

No description available.

Thesis (M.A. in Service, Leadership, and Management) -- School for International Training, 2007. / Advisor -- Jeff Unsicker Includes bibliographical references (leaves 58-60).

Submitted by Roberta Silva (roberta.silva@cprm.gov.br) on 2013-09-25T14:02:57Z No. of bitstreams: 1 isao_shintaku.pdf: 4994210 bytes, checksum: 6dcf57d8396aa73211942edabcd856b2 (MD5) / Made available in DSpace on 2013-09-25T14:02:57Z (GMT). No. of bitstreams: 1 isao_shintaku.pdf: 4994210 bytes, checksum: 6dcf57d8396aa73211942edabcd856b2 (MD5) Previous issue date: 1998 / Item withdrawn by Roberta Silva (roberta.silva@cprm.gov.br) on 2013-10-22T13:17:04Z Item was in collections: Dissertações (ID: 44) No. of bitstreams: 1 isao_shintaku.pdf: 4994210 bytes, checksum: 6dcf57d8396aa73211942edabcd856b2 (MD5) / Item reinstated by Roberta Silva (roberta.silva@cprm.gov.br) on 2013-10-23T17:10:28Z Item was in collections: Dissertações (ID: 44) No. of bitstreams: 1 isao_shintaku.pdf: 4994210 bytes, checksum: 6dcf57d8396aa73211942edabcd856b2 (MD5) / Este trabalho aborda os principais fatos econômicos que envolvem a exploração mineral, indo desde os aspectos geológicos, seleção de áreas, passando pelo o investimento inicial, suas dificuldades e deficiências, suas características, bem como o comportamento dos investimentos na exploração mineral no Brasil e em outros países. O Brasil, um dos maiores potenciais mineiros do mundo, tanto pela sua extensão territorial como por sua diversidade geológica, sofre uma perda significativa nos investimentos em pesquisa mineral, pois não oferece um clima adequado aos moldes internacionais, para entrada de capitais, comprometendo, o processo de geração de jazidas e, conseqüentemente, a descoberta de novas minas e o seu aproveitamento. Um levantamento comparativo dos investimentos em exploração mineral em diversos paises contemplando período o 1986-1995 indica que o Brasil ainda não ocupa uma posição de destaque no cenário mundial. Foram identificados nesta dissertação os riscos da exploração mineral, os tipos, e como podem ser administrados. Além disso, foi feita uma análise dos fatores que influenciam a tomada de decisão de um investimento mineral e, sob a forma de estudo de caso, foram abordados os aspectos econômicos do ouro

Submitted by Teresa Cristina Rosenhayme (teresa.rosenhayme@cprm.gov.br) on 2014-11-24T12:21:06Z No. of bitstreams: 1 José Guedes (D).pdf: 13371326 bytes, checksum: 0842b3f7fc9dbd4c07f2a98028c89ad6 (MD5) / Approved for entry into archive by Flasleandro Oliveira (flasleandro.oliveira@cprm.gov.br) on 2014-11-24T14:19:47Z (GMT) No. of bitstreams: 1 José Guedes (D).pdf: 13371326 bytes, checksum: 0842b3f7fc9dbd4c07f2a98028c89ad6 (MD5) / Approved for entry into archive by Flasleandro Oliveira (flasleandro.oliveira@cprm.gov.br) on 2014-11-24T14:19:55Z (GMT) No. of bitstreams: 1 José Guedes (D).pdf: 13371326 bytes, checksum: 0842b3f7fc9dbd4c07f2a98028c89ad6 (MD5) / Made available in DSpace on 2014-11-24T14:20:01Z (GMT). No. of bitstreams: 1 José Guedes (D).pdf: 13371326 bytes, checksum: 0842b3f7fc9dbd4c07f2a98028c89ad6 (MD5) Previous issue date: 2001

Thesis (M.B.A. (Rhodes Investec Business School)) - Rhodes University, 2009. / A dissertation submitted in partial fulfilment of the requirements for the degree of Master of Business Administration (MBA)

The Renström mine, Boliden Mineral AB, uses, among other methods, the Transverse long hole stoping method with backfill. The mine uses a cement-stabilized hydraulic fill (CHF), which is a mixture of enrichment sand, cement and water. The most important factor in relation to strength is the water cement ratio. Today, only tests have been performed on the surface and in laboratory tests. The purpose of this work is thus to study the possibility of using other types of methods that can give a better understanding of the strength of the entire filling volume. Studies on backfill containing Portland cement and sulphur have shown that the UCS strength decreases with time, which can cause problems for the mine. A leaching method (MRM leaching test) used to evaluate potential sulphide soils has been used in this study on the backfill to investigate the sulphurs impact on the cement mixture. Electrical conductivity, pH, and redox potential were investigated and gave similar results, where the higher cement levels (8%, 10%, and 12%) were indistinguishable while the lower cement content (4%) differed significantly from the other levels. This probably indicates that the higher cement levels have a greater resistance to the influence of the sulphur. The most promising results were given when the method was used on enrichment sand alone. The linear lowering of the pH value of the enrichment sand, from pH 4.9 to about pH 3, point to that the enrichment sand contains large amounts of sulphur, as previously chemical analysis has shown. This suggests that the method can best be used in an early stage before the sand is mixed with cement. The strength results on the samples showed a strength after 7 days that was in line with the 90-day strength. However, all 90 day samples had decreased in strength during the time sequence, which may be an effect of the sulphur content, but should be further investigated to be determined. The smaller size of the samples was also experienced as a challenge during the temperature measurements due to small temperature variations and environmental effects. A maturity method for predicting the strength of concrete called "The maturity method" has been investigated in this study. To determine the strength maturity relationship, both the temperature related to time and the equivalent age must be evaluated. The study showed that the method cannot be used on the mine's backfill without first making adjustments related to the lower cement content used in the backfill compared with concrete constructions, since it is not possible to determine the strength growth in the early stage as the method requires.

O espessamento é uma operação unitária que tem como finalidade separar, por diferença de massa específica entre o sólido e o líquido, sólidos suspensos em meio fluido, pela ação da gravidade. É bastante empregado industrialmente em processos contínuos no adensamento de polpas e minérios, em unidades com reação de precipitação e no tratamento de efluentes, dentre outros. Os equipamentos que realizam esta operação, chamados espessadores, são, em geral, tanques abertos de formato cilíndrico, instalados no eixo vertical com a entrada da suspensão na parte superior central, de fundo ligeiramente cônico para a retirada da polpa espessada e calha circulando o topo para descarga do líquido clarificado. As várias técnicas de projeto destas unidades contínuas são comumente baseadas em ensaios de bancada com provetas. Não é raro ocorrerem para os mesmos dados experimentais, áreas de projeto com desvios superiores a 50%. O presente trabalho visou verificar a validade das técnicas de seleção de TALMADGE-FITCH, ROBERTS e FLUXO DE SÓLIDOS, para o dimensionamento de espessadores industriais com salmoura e lodo biológico. Foram realizados para este fim, ensaios de espessamento em provetas com as próprias suspensões industriais, calculadas as áreas pelas técnicas supracitadas e comparadas com os resultados das secções dos equipamentos contínuos industriais. Os desvios médios dos diâmetros para cada técnica em relação ao espessadores industriais apresentaram contra a segurança dos equipamentos um valor de 42% para o método de Talmadge-Fitch, 45,5% para Roberts e 43,5% para o método do Fluxo de sólidos. Concluiu-se, para as condições estudadas, que os métodos de provetas utilizados forneceram valores na mesma ordem de grandeza e que requerem um fator de escala para o dimensionamento das unidades industriais contínuas. / Thickening is a unit operation that has the goal of solid-liquid separation. The principle of this separation is the difference of specific weight between solid and liquid. This unit operation is used in mineral industries, to ore concentrate, wastewater, and others. The tanks called thickeners are usually open, with the feed on the top of the equipment. The solids discharge is done trough the bottom in a conical shape. The most techniques of sizing thickeners are based on graduated cylinders, and it is a common get result that has a difference area in about 50%. This happens because security coefficient, difficulties for results interpretation and scales factors. This research has the goal to apply the techniques of selection of Solids Flux, Roberts and Talmadge-Fitch in graduated cylinders. These methods are classical for thickener sizing. A comparison has been made between the results by those methods with the data obtained from continuous industrial units for salt solution and biological brine. The shunting line for the techniques obtained was 42% for Talmadge-Fitch, 45,5% for Roberts and 43,5% for Solid Flux in the relationship with industrial thickeners. In conclusion, for the studied condition, all methods showed values in the same order and requires a scale factors to sizing the continuous thickeners.

Todos os processos industriais são forçados a cumprir especificações de produto através da inserção de rigorosos parâmetros de controle, principaJmente devido à globalização do mercado. A tendência mundial indica que cada vez mais a cor passa a ser um parâmetro primordial para a colocação do produto no mercado. Neste contexto, uma das dificuldades da indústria mineral é a inexistência de equipamentos adequados para a medição da cor de polpas de minério durante o processamento mineral. Isto se verifica principalmente para os minerais industriais que são caracterizados, na maioria das vezes, em termos de índices de alvura e amarelamento. Este traballio tem como objetivo principal avaliar o uso do equipamento Colorcell, utilizado e desenvolvido pela empresa Renner-HerrmaIlll para a produção de tintas, na indústria de processamento mineral. Os ensaios foram realizados com um equipamento similar ao original. Para se compreender as variáveis operacionais do equipamento utilizou-se um produto à base de carbonato de cálcio natural. Após a delimitação das variáveis e definição de uma metodologia de trabalho, foram caracterizados outros minerais utilizados nas indústrias de tintas, papel e plásticos. O sistema Colorcell também foi utilizado para o controle do processamento de caulim de uma empresa da região sul do Brasil. Ensaios em laboratório permitiram o ajuste de um modelo cinético para a etapa de alvejamento da empresa. A tecnologia Colorcell indica que além dos resultados benéficos ao controle de processo é possível correlacionar a caracterização colorimétrica em polpa com o método tradicional de medição de cor.

In the Kiirunavaara mine, the total length of drilling is about 1138000 meters each year with two different drilling methods. Production drilling is performed with a hammer drill while explorationdrilling is performed with a diamond drill. Explorationdrilling is applied toidentify the position ofthe ore and its tonnage. In the diamond drilling method different core samples aretaken out to provideinformation about the geological structure andwall rock in order to plan for theinfrastructure. For that reason,it isimportant that the exploration drilling isalways ahead of the production. All drill coresareexamined and stored. When a drill core isup to 1000 meters long a great amount of information needs to becompiled. The present report describestransport drilling,which impliesthat the first100 meters of each drilling will be completed with the hammer drillingmethod. The hammer drilling can be used to drill about 100 meters each day compared to coredrilling that would take almost aweek. Forthe moment there is 420 drill holes planned in Kiruna mine with a total length of 190000 drill meters. By applying transport drilling and use the hammer drilling method at the first 100 meters for eachdrill hole canthese42000 meters be drilled in 420 days,instead of 356 weeks with the core drilling method. Hammer drilling is efficient in terms of time compared to diamond drilling but does not provide the same information about the rock. Inorder to applaythe method of hammer drilling in transport drilling, different methods need to be tested that can provide information which isnecessary for mining.This report summarizes different methods that can complete a core. Amongst others, optical logging can be used wherea camera is used to film the walls inside the drill holes. In addition, samples of drill cuttingscan be collected fromhammer drillingforanalysisof the material.The report also contains information about oriented drilling. Here,an instrument is mounted on the core drill equipment. Oriented drilling does not affect the hammer drilling but can provide more accurate information about a specific area and then reduce the number of boreholes. The results from this theoretical study show that transportdrilling using hammerdrilling, during the first distance, gives a more time efficient and more profitable result compared to only core drilling. Transportdrilling has not been done during the time for this report therefor there are no practical results to comparethe present conclusions with.