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NONEL INITIATION FOR ECO-FRIENDLY BLASTINGJohn Gladious J1, Janarthanan R2, Preethivi R3, Rajakumar S4, Ramadoss R5Department of Mining Engineering, Dr.T.Thimmaiah Institute of Technology KGF,Karnataka, India1john@drttit.edu.in, il.com,4rajasiva2015@gmail.com, 5ramadossariyalur@gmail.comABSTRACTBlasting is an essential component in miningand one of the most economical method ofrock excavation applicable to both surfaceand underground mines. The effect ofblasting arising from the mining operation isone of the fundamental problems in themining industry. Rock fragmentation alsoplays a pivotal role in large scale miningbecause of its direct effect on cost of drilling,blasting, secondary blasting, crushing andthere-by affecting the overall cost ofproduction. The research investigates theeffect of initiation device on environment andthe production cost. The objectives of theresearch were achieved through fieldmeasurement and data collection. Variousinformations pertaining to blasting agentsand accessories used for blasting operationswere also collected. The results revealed thatthe flyrock, noise and vibration generatedduring blasting with NONEL are found to beminimal as compared to the safety fuse andthe electrical methods. It is also observedthat NONEL initiation increases blastingefficiency and also optimize the cost ofblasting.Keywords: NONEL, Booster, Blast HoleDrilling, Mine – PNR Mines, ANFO,DetonatorsINTRODUCTIONBlasting is the process of breaking ofbulk rock masses into loose forms, usingexplosive compounds. Here, the primary role isplayed by the explosives. The explosives are thesubstances or devices used in blasting. Theexplosives are used to produce a volume ofrapidly expanding gas that exerts suddenpressure on its surroundings and break the massinto pieces. There are three common types ofexplosives used for blasting as chemical,mechanical, and nuclear explosives. The firstchemical explosive was gunpowder. Germansmanufactured gunpowder in the early 1300s. Adetonator is a device used to trigger thisexplosive device. Detonators can be chemically,mechanically, or electrically initiated. Differentexplosives require different amounts of energyto detonate. Detonation is a necessity for theexplosive to get triggered for blasting.1.1) NONEL INITIATION:Non electric initiation system, NONEL,invented by Per Anders Persson (Nitro Nobel,later Dyno Nobel); introduced to market in1972.NONEL products can be used with all castboosters,dynamitesandcap-sensitiveexplosives. Nonel is a shock tube detonatordesigned to initiate explosions, generally for thepurpose of demolition of buildings and for usein the blasting of rock in mines and quarries.Instead of electric wires, a hollow plastic tubedelivers the firing impulse to the detonator,making it immune to most of the hazardsassociated with stray electric current. To meetthe ever increasing demand for many minerals,large opencast mines are being planned withhigh production capacities. To achieve thesehigh production targets, huge explosivequantities are being initiated in a round. As theinitiation system influences the blast results, itis necessary to select proper initiation system.Increasing economic pressures environmentalconstraints and safety mandates in recent yearshave called for precise focus on drilling andblasting operations in the mining industry. It isgenerally claimed by the manufacturers thatnon-electric shock tube system (NONEL)ISSN (PRINT): 2393-8374, (ONLINE): 2394-0697, VOLUME-6, ISSUE-6, 2019DOI: 10.21276/ijcesr.2019.6.6.38223

INTERNATIONAL JOURNAL OF CURRENT ENGINEERING AND SCIENTIFIC RESEARCH (IJCESR)improves over all blasting results. As per MMR1961, Reg.164, 1B (a) not more than of 2kgexplosives per delay are used. So, with the helpof NONEL blasting, this can be achieved whichsatisfy DGMS.1.2) REASON FOR SELECTING THEPROJECT:The effects of blasting arising from theexcavations is one of the fundamental problemsin the mining industry, rock fragmentation alsoplays a pivotal role in large scale miningbecause of its direct effect on cost of drilling,blasting, secondary blasting and crushing.Thus, it is essential to consider rockfragmentation in blast design, the optimumblasting pattern to excavate a quarry efficientlyand economically can be determined based onthe maximum production cost which isgenerally estimated based on the rockfragmentation. Blasting operations need cogentmeasures due to its remarkable influence on thestability of rock slopes especially in situationswhere blasting operation is not being carried outwith utmost or designed accuracy. Variousways in which blasting operations affects itsenvironment needed to be accountable for butthe most relevant is the structural damage due tovibration inductions, noise, fly off materials, airblast and shock waves resulting in the rockslope failure by creating a new joints orextension of the existing ones. Therefore it isnecessary to carefully apply effective blastingtechniques to achieve the desired result withinthe minimum possible cost as well to minimizeenvironmental fall outs such as groundvibration, air blast and fume production.It has been revealed that the best initiation orblasting method to apply is the non-electricalblasting method (NONEL), because of thefollowing reasons:1. It has safe environmental effect2. High productivity rate.Safe environmental effect involves bearable orminimal noise, vibration and amount of fly offrocks to the environments; different methodshave been critically analysed, which are safetyfuse method, electrical method and NONELmethod that show various degree offragmentations, noise produced and vibrationgenerated, which shows that NONEL method isthe safest way of carrying out blastingoperation.Figure 1: Nonel Initiation system.2.1) PROBLEM l constraints andsafetymandates in recent years have called for precisefocus on drilling and blasting operations in themining industry. With urbanization and minesgetting closer to humanhabitation, it isimportant to conduct blasts with safer systemsof initiation in order to control groundvibrationsandnoisewithimprovedFragmentation. It is generally claimed by themanufacturers that non-electric shock tubesystem (NONEL) improves over all blastingresults. Down the hole initiators initiate theexplosive column at a given (bottom) point .Asystematic study was taken up to analyse theinfluence of NONELs on rock fragmentation,ground vibration and noise.2.2) OBJECTIVE:1) The main objectives of Nonel Blastingare to reduce the ground vibration,noise, flyrocks generated due to blastingoperations.2) To give high blasting efficiency and tooptimize cost.METHODOLOGY3.1) BLAST HOLE DRILLING:Blast hole Drilling is a technique used inmining whereby a hole is drilled into thesurface of the rock, packed withexplosive material, and detonated. Theaim of this technique is to induce cracksin the inner geology of the surroundingrock, in order to facilitate further drillingand associated mining activity. Theinitial hole into which the explosives arepacked is known as the “blast hole”.Blast hole drilling is one of the primarysurface drilling techniques employed inmining operations today. Blast holedrilling is traditionally used wherever themining company wants to explore theISSN (PRINT): 2393-8374, (ONLINE): 2394-0697, VOLUME-6, ISSUE-6, 2019DOI: 10.21276/ijcesr.2019.6.6.38224

INTERNATIONAL JOURNAL OF CURRENT ENGINEERING AND SCIENTIFIC RESEARCH (IJCESR)mineral composition or potential mineralyield of the area demarcated for theirmining interests.3.2) PRIMING OF EXPLOSIVES:The massive use of blasting agents suchas ANFO, Heavy ANFO etc., in rock breakagehas brought about an important development ofinitiation and priming techniques. This is dueto, on one hand, the relative insensitivity ofthese compounds and, on the other hand, adesire to obtain maximum performance fromthe energy released by the explosives used inthe process. The detonation process requiresinitiation energy so that it can develop andmaintain stable conditions.3.3) PRIMER AND BOOSTER:Priming a charge is simply positioning asuitable primer within a charge or column ofexplosives. The object is to provide theprimary-initiating explosion needed to detonatethe main charge efficiently. If an explosivescolumn is not initiated properly, its optimumenergy cannot be generated. The terms “primer”and “booster” are often confused. Primer is aunit of cap-sensitive explosive used to initiateother explosives or blasting agents. A primercontains a detonator or other initiating devicesuch as detonating cord. The primer cartridgeshould be assembled at the work-site. Thetransport of cap primers is hazardous and isagainst the regulation of most countries.Priming should be done correctly byexperienced shot-firers. The commonly usedbooster in Dalmia Cement Bharat Ltd. isKELVEX P. Sometimes, after detonation, a lowsensitivity explosive may show signs of losingthe VOD progressively along its column. Thismay arise when an ANFO charge iscontaminated with water. The boosters can beplaced at appropriate intervals (about 30 timesthe blast hole diameter) to increase the VODalong the explosives column. Boosters can beplaced at appropriate spots where the ground isespecially hard and requires extra pressure forsatisfactory breakage.3.4) EXPLOSIVES:The commonly used explosive inDalmia Cements Bharat Ltd. is AmmoniumNitrate Fuel Oil (ANFO). Ammonium nitrate(AN) based explosives are the cheapest andmost frequently used commercial explosives.ANFO explosives are more frequently used forblasting than the other two types of ammoniumnitrate based explosives (emulsion and slurryexplosives. Satisfactory blasting performance, arelatively low price, and safety during blastingoperations, simple manufacture and thepossibility of mechanical loading of boreholesare the main reasons for its frequent use. Asignificant number of the individual factors thatinfluence the detonation parameters of ANFOhave been tested and determined. For pureANFO, the main factors are the properties ofthe ANprills, the fuel/oil ratio, the density andcharge diameter. It is possible to influence thedetonation parameters of ANFO by addingflammable or non-flammable components. TheAN/FO ratio was determined by an ANFO test,after the sample had been mixed, and was94.5/5.5. The measured ANFO bulk densitywas 823 kg/m3.3.5) STEMMING:Stemming enhances fragmentation androck displacement by reducing prematureventing of high pressure explosion gases toatmosphere. Good stemming maintains high gaspressure within blast hole for longer period oftime. This method helps in confine the gaseswithin a borehole and helps to prevent high costof blasting, air blast, excessive groundvibration, fly rock and boulders. This reducesenergy waste, minimizes air blast and improperfragmentation a suitable inert incombustiblematerial used to confine or separate explosive ina drill hole or to cover explosive in mudcapping is called stemming material. Stemmingis a material that is put inside of a blast hole tohelp prevent gases from escaping.3.6) BLASTING INTIATION:There are three NONEL-based initiationsystems are available:1) NONEL MS2) NONEL EZTL3) NONEL UNIDET4) NONEL LPNONEL MS, NONEL EZTL andNONEL UNIDET are used for bench blasting.Their delay times are therefore designed to suitthe conditions that prevail in bench blasting.When blasting several rows on a bench, it isimportant that the rock in the first row is givenenough time to move forwards before the nextrow starts to move. Since rock swells byapproximately 50% in volume when broken upby explosives, room must be made for thisexpansion within a very short period of time.ISSN (PRINT): 2393-8374, (ONLINE): 2394-0697, VOLUME-6, ISSUE-6, 2019DOI: 10.21276/ijcesr.2019.6.6.38225