SHRINKAGE STOPING

SHRINKAGE STOPING MININGEnglish IIStudents: TABLE OF CONTENTS1. Introducing SHRINKAGE STOPING MINING.2. Description of method.3. Principle of the method.4. Application and conditions4. Equipment.5. Ventilation. 5. Mines in the world.6. Advantages and disadvantages.7. Summary.8. Conclution.

INTRODUCTION

In shrinkage stoping, traditionally a common mining method, ore is excavated in horizontal slices, starting from the stope bottom and advancing upwards.

Part of the blasted ore is left in the stope, to serve as a working platform, and to give support to the stope walls. Shrinkage stoping method description This is a method underground mining.The ore deposit is deepOre body is steep.Grade is high to exceed costs.The stope is may be backfilled or left empty, depending on the rock conditions.Although it very selective and allows for low dilution.

Principle of the methodIt consists of digging the ore horizontal slices in an ascending sequence (boost) on the basis of the stopes.The material is continuously removed from the base.The rest is stored in the stopes, so as to serve as a working floor for the starting operation and support the walls.When the process have limit of the stopes, cease drilling and blasting and emptying the mansion starts extracting the mineral the has been stored.The pillars and bridges separating mineral mansions usually are recoveredsubsequently.

Application conditionsThis is a vertical or sub-vertical exploitation method (ore vertical structures), and thickness little (1 to 10 m.)Medium and small mining.Steeply dipping orebodies (70 90).The Inclination most be greater than 55The ore rock must be stable and competent.

Methods underground miningUnderground methodFactorUnsupportedShrinkage StopingOre strengthStrongRock strengthStrongDeposit shapeTabular / LenticularDeposit dipFairly steepDeposit sizeThin / ModerateOre gradeFairly HighOre uniformityUniformDepthShallow / moderateEquipmentShrinkage mining equipment is requirements are minimal.Airleg miner.haulage truck equipmentLonghole drillingLHD o scraper

Mines in the worldEl Olivo mineThe Maitenes, Cajn del Maipo.

Andes mountain range, near the volcano Tupungato.The rock mass is a vein of gold, studies, both prospective andThe rock mass is a vein of gold, studies, both prospective andEstimates indicate that this is a mineralized zone with a high grade and economic return.

Mines in the worldAustralian underground mining.Mike Turner Australian mine.

VentilationThe working face is ventilated by:Injecting air from the transport gallery located in the base through.

AdvantagesDraining by gravity mansionSimple method for small minesLow Capital, some machining possiblemineral and minimum support wallsmoderate DevelopmentsGood recovery (75-100%)Low dilution (10-25%)possible SelectivityDisadvantageslow to moderate productivity (3-10ton / man-shiftmoderate to high costsIntensive laborlimited Mechanizationdifficult working conditionsApprox. 60% of the "prisoner" mineral inside the mansion until the endDraperiesLoss of the mansion in emptying if not done carefullySUMARY