EXPLOSIVE AND BLASTING DESIGN AND SAFETY MEASURE: TECHNOLOGY FOR SAFE ROCK BLAST AND EFFICIENT USE OF EXPLOSIVE

Blasting Design, safety and Explosive handling and Storage: Many scholar contribution worldwide

[07/06, 8:33 p.m.] Hanif Ullah khan: The purpose of a good open pit blast design (production blast) is to achieve the following at acceptable costs...:

-fragmentation, muckpile profile for safe and efficient loading and hauling and other downstream processee

-wall stability

-minimum environmental impacts (undesirable effects of a blast): ground vibrations, noise, airblast, _flyrock_, dust and fumes.

[07/06, 8:33 p.m.] Hanif Ullah khan: I will be throwing in some of the rules of thumb for open pit blast design. A rule of thumb is basically a principle with broad application that is not intended to be strictly accurate but can be quite handy in coming up with sound and economic designs

[07/06, 8:33 p.m.] Hanif Ullah khan: -Mining equipment: equipment also has a say in the blast deasign process. Drilling equipment dictates blasthole diameter and depth limits. Loading and hauling equipment control the required fragmentation and muckpile profile.

[07/06, 8:33 p.m.] Hanif Ullah khan: Groundwater causes desensitisation of non water resistant explosives hence poor blast results. Water also increases the chances of borehole collapse and breakage.

[07/06, 8:33 p.m.] Hanif Ullah khan: *BLAST DESIGN CONSIDERATIONS*

[07/06, 8:33 p.m.] Hanif Ullah khan: -Rock type: blast design has to be rock type based taking into consideration rock mass properties for optimum blast results. E.g. technical powder factor is assigned to various rock tyoes for basing on the blasting category whether hard or medium or soft. Rock types in the hard category have a technical powder factor between 0.7 to 0.9 kg/m3 such as granite or dolerite. Medium category rocks have 0.40-0.45 kg/m3 such as dolomite or quartzite. Soft category rocks 0.25-0.35 kg/m3 eg sandstone or limestone. There are very soft rocks/minerals such as coal which have 0.15-0.25 kg/m3

[07/06, 8:33 p.m.] Hanif Ullah khan: -Groundwater: presence of groundwater dictates the use of water resistant explosives which are a bit expensive such as emulsions, slurries or water gels. Water may also force the use of borehole liners or impermeable sleeves with the non water resistant explosive such as ANFO/ANFEX/ANBA

[07/06, 8:33 p.m.] Hanif Ullah khan: Other rock properties include density/sg, young’s modulus (elasticity), ultimate compressive strength (ucs) and ultimate tensile strenght (uts)

[07/06, 8:33 p.m.] Hanif Ullah khan: -Blasting concerns: there may be sensitive structures, features or activities in the vicinity of the blasting area which may call for the blast design to carefully cater for the control of the environmental effects of blasting e.g tailings dam maybe affected by ground vibrations, powerlines, people in built up area maybe affected by flyrock airblast and noise etc

[07/06, 8:33 p.m.] Hanif Ullah khan: -Bench height: the bench height should be safe and economic to mine. 10-18m benches are the most common. If the bench height is too high, a high unsafe muckpile results, blasthole deviation becomes more defined and it becomes difficult and dangerous to scale/barr down bad hangings. Bench height should be matched to blasthole diameter. For reasonable blasthole utilisation and efficient explosive action, the explosive column should occupy at least half of the blasthole length and hence the total blasthole length should be at least 50 hole diameters although in most applications the normal range applied is 60-140 hole diameters.

[07/06, 8:33 p.m.] Hanif Ullah khan: As a rule of thumb: burden must be about 25 to 35 times the hole diameter..

[07/06, 8:33 p.m.] Hanif Ullah khan: Coming up with a a blast geometry is the most fundamental step in blast designing

[07/06, 8:33 p.m.] Hanif Ullah khan: Exactly..Thanks for clarifying. Eg if hole diameter is 115mn then the total blasthole must be 6900mm to 16100mm

[07/06, 8:33 p.m.] Hanif Ullah khan: *BLAST DESIGN FACTORS/ASPECTS*

[07/06, 8:33 p.m.] Hanif Ullah khan: -The presence of free faces: these enable the explosives energy to perform the greatest amount of work on the rock mass. As far as is practicable the free faces must face away from areas of concern to minimise projectiles and flyrock to the area. Where there is no free face a box cut is used to open up the ground

[07/06, 8:33 p.m.] Hanif Ullah khan: -Burden: correct burden ensures optimum fragmentation. If it is too small it causes premature venting of explosion gases, airblast and flyrock. Too large a burden causes poor fragmentation, flyrock and noise from the toe and crest regions, wall instability after blast, poor muckpile looseness and diggability ana also ground vibrations

[07/06, 8:33 p.m.] Hanif Ullah khan: -Spacing: it should be in the range 1.0 to 1.5 times the burden. 1.0 gives a square pattern as the burden will be equal to the spacing and is suitable fot small bench blasts, and gives efficient drilling and easy connecting up

[07/06, 8:33 p.m.] Hanif Ullah khan: Thanks for giving us the rules of thumb they make blast design easier

[07/06, 8:33 p.m.] Hanif Ullah khan: Spacing which is 1.15 times the burden gives a staggered pattern which has the advantage of better explosives distribution and hence better fragmentation

[07/06, 8:33 p.m.] Hanif Ullah khan: As a rule of thumb: spacing should not be more than half the depth of the borehole...

[07/06, 8:33 p.m.] Hanif Ullah khan: -Explosive charge distribution: this is a function of charge length, stemming length and subdrill

[07/06, 8:33 p.m.] Hanif Ullah khan: -Blasthole diameter: large diameter holes have the following advantages:- they are fewer to drill, suitable for high benches with cheap bulk explosive, fewer initiation units (detonators and primers), and more volume of rock is broken by a single blasthole. Smaller diameter holes give better explosives distribution in yhe rock mass hence better fragmentation, less oversize material and less environmental effects. As diameter of blasthole increases, a subsequent increase in powder is required to maintain optimum fragmentation

[07/06, 8:33 p.m.] Hanif Ullah khan: -Blasthole angle: blastholes inclined in the the direction of the free face ensure better uniformity of burden from toe to crest (ideally the blasthole should be parallel to the free face). Correct blasthole angle addresses toes, stumps and floor conditions whilst controlling overbreak, noise airblast and flyrock. Angled holes also ensure better throw and muckpile looseness.

[07/06, 8:33 p.m.] Hanif Ullah khan: As a rule of thumb: the subdrill can be estimated to be in the range of 8-12 times the hole diameter or 0.2-0.5 times the burden.

[07/06, 8:33 p.m.] Hanif Ullah khan: *sub drill:- the main purpose of subdrill is to control floor and toe conditions. It also allows for the fall back of drill cuttings and sludge since flushing the hole is not 💯 effective. In some cases the subdrill may not be necessary and may actually be backfilled eg if a prominent geological interface exists such as blasting a coal seam

[07/06, 8:33 p.m.] Hanif Ullah khan: *charge length: also a function of linear charge density (kg/m) which is primarily controlled by the explosive density. Charge length must be greater 20 times the hole diameter

[07/06, 8:33 p.m.] Hanif Ullah khan: Charge length= hole length - stemming length

[07/06, 8:33 p.m.] Hanif Ullah khan: Stemming shorter than 20 times hole diameter usually leads to excessive noise, airblast, flyrock and overbreak.

[07/06, 8:33 p.m.] Hanif Ullah khan: -Bench height = stemming length + charge length. Total charge length = charge length + subdrill. Stiffness ratio (bench height/burden) is also another check to the blast design:- it must range from 3-4 for good control of undesirable effects and for optimum fragmentatio.

[07/06, 8:33 p.m.] Hanif Ullah khan: 👍👍

The main purpose of subdrill is to provide good pit floor level.

It not necessary in strata or layered deposit as they tend to produce smooth floor.

Such as coal as the presenter had mentioned

[07/06, 8:33 p.m.] Hanif Ullah khan: *Stemming: inert material that fills up the remainder of the blast hole to the collar. It serves to confine the explosion and contain the detonation gases. Stemming controls fragmantation and displacement, airblast, noise and flyrock. Drill cuttings are usually used as stemming material but but crushed rock aggregate gives better and more effective stemming. The crushed rock size should be 10% of the blasthole diameter. Care should be taken during charging as the drill cuttings tend to contaminate the exllosive. Stemming length should be 0.7 - 1.2 times the burden. As a rule of thumb: stemming length should be 30 - 40 times the hole diameter if drill cuttings are used and 20 - 30 times hole diameter if crushed rock is used. generally it can also range from 20 to 60 times the hole diameter depending on geology and rock properties

[07/06, 8:33 p.m.] Hanif Ullah khan: -Blast timing: blast results depend on interaction of blastholes of blastholes- the sequence in which blastholes are initiated and the time interval between successive detonations. Bkastholes must be detonated in a controlled sequence with proper delays to achieve the desired blast result

[07/06, 8:33 p.m.] Hanif Ullah khan: -Geology: discontinuities, bedding plane partings, joints are the main geological factors. Absence of joints imply that more explosive energy will be required to fragment the rock. Joints can cause fragmentation to be course or fine depending on joint spacing. Joints cause venting of gases leading to air blast, flyrock, irregular face walls, increased risk of overbreak, instability and cutting off of adjacent blastholes.

[07/06, 8:33 p.m.] Hanif Ullah khan: Timing dictates the muckpile profile which is a function of the requirements of the loading equipment e.g a shovel works best on a high muckpile whilst a dragline works best on a flat muckpile

[07/06, 8:33 p.m.] Hanif Ullah khan: Let's solve an example. How to calculate specific charge.

How to calculate powder factor.

How to calculate specific drilling.

How to calculate explosive required for Blasting

[07/06, 8:33 p.m.] Hanif Ullah khan: I will like to make contribution to the bench height selection.

Majorly bench height selection depends on three factor during open pit mine design.

These factors are;

1. The ore dilution control

2. Loading equipment boom height

3. Geological factor as in Discontinuity/slope failure & stability

[07/06, 8:33 p.m.] Hanif Ullah khan: *At the end of the day a blast design must spell out the following:*

- ```blast geometry- burden, spacing, stemming, charge length, subdrill

- powder factor

-drilling patter and blasthole layout

-initiation design```

[11/06, 2:25 p.m.] Taiwo Mining Eng: Great kamran👍👍.

The important of decking includes

[11/06, 2:26 p.m.] Taiwo Mining Eng: I. Reduce the amount of Explosive use per charge

[11/06, 2:28 p.m.] Taiwo Mining Eng: 2.it a blast control techniques, as in air decking.

[11/06, 2:30 p.m.] Taiwo Mining Eng: 3. It also aid efficient distribution of Explosive shock wave per charge length

Here's my contribution on the Transportation of Explosives. 

The vehicle carrying explosives should:

1) Run on at least 4 wheels

2) Be in a serviceable condition

3) Be rubber lined

4) If it's an open truck then it should be covered with tarpaulin to cover explosives.

5) Should travel at a speed not exceeding 50km/hr

6) Should have a sprug chain which will be constantly in contact with the ground. 

7) Should have serviced fire extinguishers. 

8) Should also have red flags indicating it's carrying explosives. 

Explosives can only be transported during daytime, between sunrise and sunset.

Fly rock and its control 

[03/07, 10:03 p.m.] Taiwo Mining Eng: By definition,

Flyrocks are pieces of rock ejected from the blast site during Blasting as a result of the u control execution of Explosive energy

[03/07, 10:04 p.m.] Taiwo Mining Eng: Flyrock as a verb, is the unwanted projection of rock piece from a blast site during Blasting.

Which is prompt to cause damage to nearby building, machine, mine workers to mention few

[03/07, 10:06 p.m.] Taiwo Mining Eng: Flyrock can be classified into three base on the projectile direction.

[03/07, 10:06 p.m.] +27 79 654 6330: Stemming is very important to control flyrock aswell as P F

[03/07, 10:07 p.m.] Taiwo Mining Eng: 1. Catering flyrock: rock moving in any direction from top of the blast face

[03/07, 10:07 p.m.] Taiwo Mining Eng: 2. Face blast: rock moves in front direction

[03/07, 10:08 p.m.] +27 79 654 6330: Burden and spacing also very important

[03/07, 10:08 p.m.] Taiwo Mining Eng: 3. Rifting: rock moves upward from blast face

[03/07, 10:11 p.m.] Taiwo Mining Eng: The following are the causes of flyrock during Blasting,

1. Poor o inadequate stemming

2. Faulty blast design

3.misfire

4. Poor firing sequence

Just to mention few

[03/07, 10:15 p.m.] Taiwo Mining Eng: How does poor or inadequate stemming causes flyrock production?

Mostly, poor stemming length or stemming material result in put out of hole.

Upon Explosive initiation, the generated energy, gas energy and shock wave tend to search for weak zone as it support it ease movement.

I adequate stemming causes Explosive energy to throw out from the blast top, this result in the projection of rock particles.

[03/07, 10:17 p.m.] Taiwo Mining Eng: To misfire,

For the causes of this presentation, I will define misfire as the Explosive left unfired during Blasting.

[03/07, 10:20 p.m.] Taiwo Mining Eng: In view of this definition,

During Blasting, each hole rows have specific burden to fragment.

Meaning, each hole has a specified rock volume to break.

Having some unblaster hole or hole row affects the efficient work of other holes

[03/07, 10:22 p.m.] Taiwo Mining Eng: The usage of Explosive energy distribution depends on the quantity of work load on each hole.

If the rock to be broken by a hole row is to large, the Explosive energy tends to put out on blast top.

[03/07, 10:28 p.m.] Taiwo Mining Eng: Firstly,

Faulty blast design can be in different factor:

1. Poor burden and spacing selection

2. Use of large powder factor

3. Bad design in related to pit slope angle and the first hole row

[03/07, 10:28 p.m.] Taiwo Mining Eng: Starting with poor burden and spacing

[03/07, 10:30 p.m.] Taiwo Mining Eng: Small burden, causes large release of energy after rock slabbing.

At, Explosive detonation point shock wave are released first to create cracks, the follow by gas energy

[03/07, 10:33 p.m.] Taiwo Mining Eng: If the burden use is small compare to the powder factor use, the rock mass cracking occur nearly simultaneously with the gas energy release.

This cause more of the shock energy to project the rock far away from the blast site.

Despite the production of finer rock particles,

The unused energy throw the rocks farer distance

[03/07, 10:34 p.m.] Taiwo Mining Eng: Large powder factor release excess energy beyond that require for cracking, other unused energy is create air wave and surface wave which project rock far from the blast site

[03/07, 10:35 p.m.] Taiwo Mining Eng: Bad design in related to pit slope angle and first hole row.

[03/07, 10:43 p.m.] Taiwo Mining Eng: This start from,

1. Proper blast design: in place of good burden selection,good powder factor or specific charge.

2.drilling: driller should observe the variation in the drilling speed. This will help to discover if there is weak zone in the rock so as to put this into consideration during blast design

[03/07, 10:45 p.m.] Taiwo Mining Eng: 3.Geology of the blast area: present of mud seams (coal), natural joints, fracture or cavities.

This must be give proper consideration to during blast design

[03/07, 10:46 p.m.] Taiwo Mining Eng: 4. Explosive loading up: while charging in watery holes, sufficient care has to be taken to prevent misfire.

Also,explost selection must be done in view of the mine site condition

[03/07, 10:50 p.m.] Taiwo Mining Eng: Other means of controlling flyrock includes:

1. Muffling or Covering: This involve using blast mat, chain to cover the blast during Blasting.

This can also be done by the use of sand.

The blast after charging and connecting/chaining, is covered with sand to prevent rock projection

Explosives storage and transportation.....

[25/06, 8:52 p.m.] Taiwo Mining Eng: Blasting licence is granted to company fireman under the operation of a competent mining Engineer.

The Blasting license is to be renewed annually

[25/06, 8:58 p.m.] +263 77 502 0991: What is FISH????

[25/06, 8:58 p.m.] +263 77 502 0991: These are the four sources of Ignition

[25/06, 8:59 p.m.] +263 77 502 0991: When an explosives is subjected to any of these four they are high chances of an explosion

[25/06, 9:00 p.m.] +263 77 502 0991: FISH so that you dont forget

[25/06, 9:00 p.m.] +263 77 502 0991: F stands for Friction

[25/06, 9:01 p.m.] +263 77 502 0991: when an explosive material is su bjected to friction it will explode eg a bucket of your LHD lashing and explosives are on the ground especially your sensitive products such as detonators they will explode

[25/06, 9:01 p.m.] +263 77 502 0991: I stands for Impact

[25/06, 9:02 p.m.] +263 77 502 0991: a boulder falls on to your explosive the next thing is an explosion

[25/06, 9:04 p.m.] +263 77 502 0991: your static electricity eg your lightning

[25/06, 9:04 p.m.] +263 77 502 0991: The reason why we put chains on vehicles conveying explosives

[25/06, 9:04 p.m.] +263 77 502 0991: H stands for HEat

[25/06, 9:05 p.m.] +263 77 502 0991: Heat will cause your explosives to explode

[25/06, 9:05 p.m.] +263 77 502 0991: Remember Friction Impact Static and Heat these are your sources of ignition

[25/06, 9:06 p.m.] +263 77 102 8782: As explained by Moshen, the explosives are stored in a Magazine that is licenced under the Explosives Regulations. There are 2 types of Magazines namely Immovable and portable Magazines. There are specifications that are supposed to be met in the construction of the magazine that includes the provision of ventilation flues, lining the interior with non ferrous material and provision of an earthen mount around the magazine.

[25/06, 9:06 p.m.] +263 77 102 8782: The Magazine Master also displays his official appointment in the magazine.

[25/06, 9:06 p.m.] +263 77 102 8782: Also to be included in the Magazines are the permits and licences for storage which stipulates the type and quantities that can be stored in that particular magazine.

[25/06, 9:06 p.m.] +263 77 102 8782: The Magazines are located away from populated areas and away from public infrastructure. The regulations also stipulate the respective minimum distances depending on the size or capacity of the Magazines.

[25/06, 9:10 p.m.] +263 77 102 8782: Remember the closer you are to an explosion the less noise you will hear

[25/06, 9:12 p.m.] +263 77 502 0991: Also the law stipulate the type of material that you use for the construction of the magazine

[25/06, 9:13 p.m.] +263 77 502 0991: here in Zim for your immrovable magazine you use steel reinforced concrete at least 150mm for the wall floor and roof

[25/06, 9:14 p.m.] +263 77 502 0991: for your portable magazine the steel plate must be at least 5mm

[25/06, 9:20 p.m.] Taiwo Mining Eng: Here for the portable magazines steel plate of 5-6mm is use to construct a container. With temperature regulated linears

[25/06, 9:21 p.m.] +263 77 502 0991: The temperature inside the magazine must not exceed 35 degreees

[25/06, 9:21 p.m.] Taiwo Mining Eng: For the immovable, a special build is usually use.

Thou I haven't been to any before but.

I learn about it from Engineers.

[25/06, 9:24 p.m.] Taiwo Mining Eng: Also,

Old Explosive are used first before the new Explosive

[25/06, 9:30 p.m.] +27 79 654 6330: Adhere to speed limit S A 80 km/h

[25/06, 9:33 p.m.] Taiwo Mining Eng: All vane wired part/connection must be properly insulated

[25/06, 9:33 p.m.] +263 77 505 6630: Yes it's possible though not advisable. You just have to make sure the ox drawn cart travels at walking speed.

[25/06, 9:36 p.m.] +27 79 654 6330: Detonators and pakaged explosives seperatly

Misfire: 

[25/07, 10:04 p.m.] +591 72391160: The second point is that we must be aware of what kind of misfire we are facing...

[25/07, 10:06 p.m.] +591 72391160: As in the presentation we have three main factors for misfere to occur...

[25/07, 10:08 p.m.] +591 72391160: So we as leaders must identify what happened. And the best thing is always to identify the root cause...

[25/07, 10:08 p.m.] +263 77 109 9677: *In Zimbabwe this is how we legally define a misfire*

A “misfire” in relation to a charge of explosives means a charge which has failed to explode either wholly 

or in part;

[25/07, 10:21 p.m.] +91 88775 55835: *MISFIRE* it's means Detonator failed to explode the explosive charged within the Hole. MISFIRE is a Very Dangerous for miner's who involved in Blasting section.

[25/07, 10:23 p.m.] +263 77 109 9677: *Based on these definition, From Experince,*

Misfires are caused by.

1. Faulty blasting cables

2. Bad timing sequencies eg causing cutoffs

3. Leaving some explosives column(s) from the firing connection.

4. Faulty blast initiators, eg. Bad or faulty detonators, safestarts, shirstarters.

5. Poor explosives combinition eg.6D detonators and non cap sensitive explosives.

6. Bad safety fuse capping

* Although rearly*

1. Bad product:

2. Wrong cut positioning and burning front issues

[25/07, 10:26 p.m.] +91 88775 55835: It is totally waste of time and money so as good engineer we must having good Knowledge as well as practical experience about MISFIRE. 

As a good mining engineer we must know about MISFIRE-

1) How to deal with misfire.

2) what type of precautions should be taken.

3) Know the actual place of MISFIRE Shots

[25/07, 10:28 p.m.] +27 79 543 2075: The best way to deal with a misfired hole is to drill a relieving hole 2m apart from the misfired hole and re-blast it

[25/07, 10:29 p.m.] +91 88775 55835: MISFIRE occurred due to-

Bad quality of explosive

Defective Detonator

Broken detonator lead

Damaged Exploder

[25/07, 10:30 p.m.] +91 88775 55835: Wrong connection

[25/07, 10:30 p.m.] +27 79 543 2075: To add on that when personnel stops thinking or when rushing and through ignorance

[25/07, 10:37 p.m.] +91 88775 55835: What Precautions should be taken after Hole goes to misfired

1) the cable should be checked before Blasting

2) Exploder should be examined at every 3 months by competent person 

3)only good quality of explosive and detonator shall be used 

4)it is better to having two single core cable for shotfiring with maintained distance.

5)the circuit should be tested for continuity by a Galveno meter

[25/07, 10:43 p.m.] +91 88775 55835: How to deal with misfired-

1)all the entrance to the face should be fenced 

2) No person should enter at the site of blasting after 30 minutes

3) Another reliving Hole shall be made at the distance of 30 cm 

4) after fired a reliving Hole defective Detonator and explosive cartridge shall be searched in Blasted ore and take out to the surface for know the Reason.

[25/07, 10:44 p.m.] Taiwo Mining Eng: Thanks to the two presentery

[25/07, 10:44 p.m.] Taiwo Mining Eng: Presenters*

[25/07, 10:44 p.m.] Taiwo Mining Eng: I will be starting mine now

[25/07, 10:45 p.m.] Taiwo Mining Eng: They have said slot, so I will not repeat there areas.

But give detail explanation on some

[25/07, 10:45 p.m.] Taiwo Mining Eng: If you are following say

Following...

[25/07, 10:47 p.m.] Taiwo Mining Eng: Adding to all mention definitions,

Misfire is the complete or partial failure of a Blasting charge to detonate/explode as planned.

[25/07, 10:49 p.m.] Taiwo Mining Eng: I want us to know this that,

Misfire is not limited to charge failure at initiation, but also extend to accidental detonation of Explosive and other Blasting accessories

[25/07, 10:50 p.m.] Taiwo Mining Eng: Since misfire I very hazardous, every reasonable means available to site manager must be taken to avoid it occurrence

[25/07, 10:50 p.m.] Taiwo Mining Eng: I will be taking about,

How to recognize misfire

[25/07, 10:52 p.m.] Taiwo Mining Eng: After firing, a proper checking of face and muckpile must be done to ensure that there is no indication of misfire

[25/07, 10:52 p.m.] Taiwo Mining Eng: The occurrence of misfire during Blasting result into the following blast challenges:

[25/07, 10:53 p.m.] Taiwo Mining Eng: 1. Production of Noxious fumes and toxic dust

[25/07, 10:53 p.m.] Taiwo Mining Eng: 2. Inadequate ground movement

[25/07, 10:53 p.m.] Taiwo Mining Eng: 3. Poor fragmentation

[25/07, 10:53 p.m.] Taiwo Mining Eng: 4. Unusual blast sounds or vibration rate

[25/07, 10:53 p.m.] Taiwo Mining Eng: 5. Flyrock

[25/07, 10:54 p.m.] Taiwo Mining Eng: 6. Evidence of undetonated Explosive in bench face or in muckpile

[25/07, 10:54 p.m.] Taiwo Mining Eng: This 6 Condition is what was a Blasting Engineer can use during blast to at least predict if there is misfire or not

[25/07, 10:55 p.m.] Taiwo Mining Eng: The occurrence o misfire (now during Blasting) is not dangerous but the post blast effect is the main problem

[25/07, 10:56 p.m.] Taiwo Mining Eng: How can this 6 sign occur and why does it occurred?

[25/07, 10:57 p.m.] Taiwo Mining Eng: Production of Noxious fumes and toxic gases is as a result of alteration in the Explosive oxygen balance due to incomplete detonation

[25/07, 10:58 p.m.] Taiwo Mining Eng: As we all know, oxygen balance is very important.

It dictate the type of gas, time and dust produce from Explosive at detonation

[25/07, 11:01 p.m.] Taiwo Mining Eng: Each Explosive has been tested at production and all gases reacting with oxygen had been balance in such a way that, at detonation, only those gases that are not poisonous are released.

Incomplete or partial detonation of Explosive led to negative oxygen balance.

This final cause the complete production of Noxious fumes which is hazardous

[25/07, 11:03 p.m.] Taiwo Mining Eng: As a Blasting expertise, we should know Blasting 100 charge holes will generate more ground movement than 70 charge holes.

As the load density will be different

[25/07, 11:04 p.m.] Taiwo Mining Eng: Also, poor fragmentation result from misfire

[25/07, 11:06 p.m.] Taiwo Mining Eng: During Blasting, failure of two or more holes affect burden movement.

It create more oversize and poor fragmentation.

[25/07, 11:06 p.m.] Taiwo Mining Eng: We have talk about this in our past WEBINAR, so I won't be talking more on it 

If you want more.

Message me privately

[25/07, 11:07 p.m.] Taiwo Mining Eng: What are the post Blasting misfire inspection

[25/07, 11:07 p.m.] Taiwo Mining Eng: Inspection of misfire after Blasting is a dangerous task

[25/07, 11:08 p.m.] Taiwo Mining Eng: In all circumstances must be done in accordance with site rules

[25/07, 11:09 p.m.] Taiwo Mining Eng: Hazard exist not only from the remaining undetonated Explosive but also from the post blast environment

[25/07, 11:11 p.m.] Taiwo Mining Eng: It is possible that misfire Explosive to detonate after some time, therefore it is essential that adequate trained personel who regularly check the muckpile and face during loading operation

[25/07, 11:13 p.m.] Taiwo Mining Eng: Unchecked misfire is very dangerous, as when load and transport to the processing plant can detonate during crushing.

We study the four initiation stimuli from @⁨Moshy⁩ presentation.

FISH: Friction, impact, shock and heat

[25/07, 11:14 p.m.] Taiwo Mining Eng: Impact during crushing can initiate undetonated Explosive in Boulder socket.

[25/07, 11:15 p.m.] Taiwo Mining Eng: The extent and nature of misfire must be determined

[25/07, 11:15 p.m.] Taiwo Mining Eng: As soon as possible after the misfire ha be defected

[25/07, 11:16 p.m.] Taiwo Mining Eng: After check and clear: The *All Clear* sign should be given.

But if not yet clear the dangerous zone must be barecade

[25/07, 11:16 p.m.] Taiwo Mining Eng: Barricade*

[25/07, 11:17 p.m.] Taiwo Mining Eng: *How to deal with misfire*

[25/07, 11:18 p.m.] Taiwo Mining Eng: Now after we have done our post Blasting inspection and confirm the occurrence of misfire

[25/07, 11:18 p.m.] Taiwo Mining Eng: These are some ways to deal with the misfire

[25/07, 11:19 p.m.] +27 79 707 2601: You report n barricade so tht u can do re blast

[25/07, 11:19 p.m.] Taiwo Mining Eng: 1. Removing stemming and re-priming

[25/07, 11:20 p.m.] Taiwo Mining Eng: These are some precautions to observe when doing this

[25/07, 11:20 p.m.] Taiwo Mining Eng: 1. When the detonator is close to the undetonated Explosive, stemming removing with force should not be attempt

[25/07, 11:22 p.m.] Taiwo Mining Eng: 2.In case of electric detonator the use of high velocity air should not be attempted as it can generate static charges sufficient to initiate electric detonator

[25/07, 11:23 p.m.] +234 806 562 9334: In a situation where the down the hole has been cut by blasted rock, let's say you have five charge holes that misfire. What did you sugest

[25/07, 11:26 p.m.] Taiwo Mining Eng: 3. Bulk Explosive can be washed out if misfired shotholes.

But special care must be taken in removing the cartridge expecially where detonators are involved

[25/07, 11:27 p.m.] Taiwo Mining Eng: 5. Under no circumstances must Explosives or detonator be removed from a drill hole by pulling on the detonating cord or detonator lead

[25/07, 11:28 p.m.] Taiwo Mining Eng: 6. Use suitable extracting tools if required

[25/07, 11:28 p.m.] Taiwo Mining Eng: Soon of the advantage of using high pressure water to flush Explosive during misfire

[25/07, 11:30 p.m.] Taiwo Mining Eng: 1. It desensitise any non water proof Explosive and dissolve high concentration of water soluble Explosive ingredients

[25/07, 11:30 p.m.] Taiwo Mining Eng: 2. It overcome the mechanical lock of stemming material comprising chippings

[25/07, 11:31 p.m.] Taiwo Mining Eng: Other way of dealing with misfire is by

*Drilling and firing relieving holes

Blasting optimization: Micro fracture increase to supplement rock breakage

Blasting is the technology use in breaking rock mass or boulders into specified require sizes by the use of Explosive.

The main objective of Blasting is to reduce rock/Mineral size so as to minimize cost of comminution and other downstream processes.

Poor fragmentation affect other Mining operations like; loading, Haulage, crushing, and separation process.

It also increase production cost and operation cost. Most Quarry and mine practice secondary Blasting or implement hydraulic breaker to further reduce Blasting output.

It therefore good to subscribe to better blast design to ensure good blast output result so as to avoid further reduction expenses.

What is micro fracture?

Fractures are crack or breakage in rock mass.

Micro fractures are the cracks create in rock mass by Explosion shock waves during Explosive charge detonation.

What is the important of micro fracture in rock fragmentation?

The micro fracture creates slabbing in rock mass and through this cause the failure of the rock and Explosion after high pressure gas fill up the fractures.

How can we increase micro fracture in rock during Blasting?

Find my response in the attached pictures.

MINING JOB SEARCHING KEY: THE SECRET JOB DOOR

It never ends until you give up!! As an experience mining Engineer or graduate you have hundred plus job opportunities available online for you.

All you need is to get the formula right.

The general formula for you getting job is titled: "Add up and Network it"

You first add up value and do the networking.

Recently I was baffled about the available opportunities in Mining after checking through people's request for job on Facebook pages and groups.

I decided to take this up and Network friends, make online research to get the crystal view of mining in the world.

I sign up for more than four (4) website and keep searching for mining job basin, firstly worldwide and later National.

I was supprise to access and get notification from more than three websites on available Mining job from companies.

Many companies release their vacancy advert internally, it requires smart job seekers to gain access to this.

I will be sharing with us five Giant job searching app and website that have access to mining company job vacancy.This websites give update on job vacancy and also provide you with information about the company, and also gives information about possible interview questions.

All you need is networking and getting the formula right!

Below are some garantee Job searching engine:

1. Glassdoor Website

Access Glassdoor Website HERE

2. Ngcareer website (Nigeria)

Access ngcareer website Here:

3. LinkedIn website

Access LinkedIn here

4. Careermine website

Access Careermine website Here

5. Ca.indeed website

Click here to access indeed website

Gem Stone Mining Tips

Cost and Technical Requirements for starting/operating a small scale gemstone Mine

Nigeria is a blessed a country with a lot of minerals most especially solid minerals like Gemstone e.g Gold, Diamond, Ruby, Tourmaline, Sapphire and more 

To start with, Artisanal and Small-Scale Mining (ASM) are formal or informal operations with predominantly simplified forms of exploration, extraction, processing and transportation. ... While ASM can provide a mean to generate income to get out of poverty, it can also be a way to trap miners and the families in poverty.

Briefly, on the mineral we are about to get is technical requirement and cost for mining the mineral.

Gemstone is a piece of mineral with special properties like colour, hardness among others which makes it different from other earth forming Mineral.

This mineral is such that after it has been cut and polished is made into a piece of jewelry or another accessory

FORMATION OF GEMSTONES

Gemstones are of substantial monetary value for its beauty or shine, which are form from the eruption of molten magma to the surface, due to slow cooling, temperature and pressure.

Examples of this mineral are

1. Tourmaline which semi-precious stone

2. Ruby

3. Gold a precious stone

4. Diamond 

5. Sapphire

6. Emerald 

1. Colour: all gemstones are of specific colour which varies from lighter-darker, more or less vivid

2. Cut: this refer to the shape or design of the stones e.g stone or bottle shape, tourmaline is of bottle shape, quart is hexagonal in shape e.t.c 

3. Carat weight: gemstone is measured by its weight not by its dimension and one carat is approximate to 0.2 gram

4. Hardness

GEMSTONE MINING AND PROSPECTING METHOD 

OPEN CAST MINING METHOD

Gemstone is a solid mineral which is mostly been mine on the surface of the earth using open cast mining method with the depth less than 320m. Open cast mining method is a  class under surface mining method. It use for the extraction of shallow depth deposit, those with shallow overburden thickness.

PROSPECTING METHOD

1. Sluicing: channel of running water, and wash scoops of ore and dirt with a framed screen so that only stones are left. 

2. Creeking/Panning

Mountain mining operations may have creeks flowing through the terrain that are available for prospecting. The creeks will be up to knee-deep and can contain gems that have been deposited in the waters from surrounding mines through erosion.

Some people like to look for gems by peering at the exposed gravel and rock. Screening, or panning, is more common and more productive. To pan, you need a hand shovel and a screen, which is some type of metal grid enclosed in a frame. Screening is similar to straining things in the kitchen: dump a shovelful of gravel on the screen and strain with the available water.

 Digging

To dig for gems is to cut into the ground or in a mine's vein, hoping to find a mother lode that yields a valuable find. This kind of prospecting is real labor and requires a rock hammer, shovel and bucket. Mining operations will usually supply them for a fee. Equipment you bring from home might have to be approved before you can use it.

Before you can start mining your gemstone legally, you have to acquire some license and lease, you have to know the equipment to use and there prices this will tell you the amount you need to start your operation known as CAPITAL

THE TYPE OF LICENSE TO ACQUIRE AND HOW TO OBTAIN THEM WITH THERE COST 

There are major types of mining leases or licenses or permit in Nigeria, which are commonly applicable in the Nigerian mining sector they are as follows

Reconnaissance Permit

Exploration Licence

Small Scale Mining Lease

Exploration License

Possess or Purchase License

Water Use Permit

Export License

The functions and requirements for all of the above listed licenses can be summarized as follows:

Exploration License: Exploration license is granted to any individual company that intends to prospect for mineral resources in Nigeria. This type of license allows the licensee to search for the required mineral resources deposited in the areas covered by the license.

Mining Lease: A mining lease in Nigeria is granted to any company that intends to start mining of mineral resources in commercial quantity in Nigeria. This type of license proceeded by an exploration license. A company seeking to obtain a mining lease must have found or located mineral resources satisfactory quantities making application for the lease. 

The major requirements for obtainment or grant of mining lease are as follows:

Certified true copy of Incorporation documents

Completed application forms

Pre-Feasibility Report

Prospecting plan

Payment of processing fee

Evidence of financial capability or banker reference letter

Evidence of technical competence or COMEG accredited geologist

Irrevocable consent from land owner(s) and/or occupier(s) to the applicant

Attestation of non-conviction of criminal offences under the Act by a Lawyer

 

Under the Nigerias Minerals and Mining Act, 2007, only corporations can obtain a mining lease in Nigeria. And when a mining lease is issued, the duration is for a period of 25 years.

Small Scale Mining Lease: The Small Scale Mining Lease, as the name appears, is a smaller version of mining license. The procedure for obtainment of the SSML is a little bit similar to that of Mining Lease, with some distinctions. When SSML is issued, the duration is for 5 years. However, an SSML can be converted to proper Mining License if the scale of production or usage of it exceeds the criteria stipulated for SSML.

Possess or Purchase License: The Possess or purchase license is a mining license in Nigeria, which is required from any entity seeking to trade in mineral resources. Under the Nigerian Mineral laws and regulations, it is an offence to possess or to be moving mineral resources from one place to another without the requisite license. Possess and Purchase creates an avenue for any corporation that does not own or possess a mining lease to directly engage in mineral trading or exporting.

Some of the requirements to obtain a Possess and Purchase License are as follows:

Certificate of Incorporation of the Company, including CAC Form 1.1

Application letter

Tax Clearance

Attestation of non-conviction for a criminal offence by a Legal Practitioner

Bankers Reference Letter

Letter of consent from a Mineral title holder

Evidence of technically competent person (credentials of Mining Engineer)

Payment of prescribed fee

The duration of the license is one-year subject renewal.

Possess or Purchase License

Mineral Buying Center License

Export License

REQUIREMENTS FOR OBTAINING A MINING LICENSE IN NIGERIA

Before going into the steps involved in applying for a mining lease in Nigeria, it is important to identify the various requirements for each stage of the process. The requirements for a mining lease and a small scale mining lease are the same, they are:

Pre  grant conditions:

The following documents are to be submitted with the duly completed application forms

Pre-Feasibility Report with COMEG seal and signature

Prospecting plan / reserve estimation

Extant Exploration license

Evidence of financial capability

Evidence of technical competence

Irrevocable consent from land owners or occupiers.

Attestation of non-conviction of criminal offences under the Act

Evidence of payment of processing fee

Certified true copy of certificate of incorporation 

Minerals to be exploited Survey plan of specified area to be submitted

     13. Notice to land owners (private or state land) with a response on rate to be paid

2. Pre-Development conditions (post-grant)

1. Environmental Impact Assessment (EIA)

2. Community Development Agreement (CDA) copy to be Submitted to MCO and all relevant departments in the Ministry

3. Compensation (section 107)

4. Mine Closure plan/Rehabilitation plan

5. Reports from state bodies/ MIREMCO

APPLICATION FEES

SERVICES FOR

MINING LEASE ML AND

SMALL MINING LEASE SSML

Application Processing fees

N50,000 (ML)

N10,000 (SSML)

Annual Service Fee

N25,000 (ML)

N10,000 (SSML)

Renewal Fee

N250,000 (ML)

N30,000 (SSML)

Late Renewal

N100,000

N100,000

Equipment & machine use and there price 

Pneumatic jackhammer: 185,000Naira

 Hydraulic air compressors (Indersol rand XP800):4,500,000Naira

Backhoe excavator:37,000,000Naira or 

to rent #120,000/day

Carbide-Tipped Hand Points & Chisels...... #700 each

Washing plant shaking table (1tn/hr)........ Old 417,700Naira

new 1,020,000($3,000)Naira

Pumping machine for dewatery action in case......... 45,000Naira

Another option for mining can be MANUAL MINING option which require less amount than the above mining option. This mining method comprises of less equipment  as follow:

1. Air Compressor 

2. pneumatic jackhammer : jackhammer is been employ in this operation because most of Gemstones like Tourmaline can be found in a vault zone where their casing is very hard in layer ordinarily, hammer and chisel  can not be use to remove the hard layering this case we have to employ the use of jackhamer 

3.clearing of overburdened with the use of back hole excavator by renting form other company at the rate of #100,000 to #120,000 per day

4. Digger, shovel, hammer, carbide tipped head chisel, head pan 

In short for 

5. Alot  of human labour is required

6. Pumping machine and generator to power them, 

Washing plant is not listed among because this is done by the unskilled workers to wash the minerals in an alternative  way instead of using washing machine 

Personnel Requirements

Drillers 2

Blasters 1.                    #50,000

Excavator Operators 1

Equipment Operators 1

Mechanics 1

Laborers/Maintenance  30,000 to #40,000

Personnel 32

Salaried Personnel Requirements

Manager 1

Engineer 1                                100,000

Geologist    1

Supervisor  3

Accountant  0

Personnel  0

Secretary  1

Security  1

  ------

Total Salaried Personnel  8

Primary Supply Requirements

Diesel Fuel liter/day

Powders  #not consistent in buying per day

Caps

Primers

Drill Bits

Det. Cord m/

Cost Summary

Operating Costs

Capital Costs

Equipment Purchase #43,000,000 (new equipment).    #6,000,000 (for old and equipment rent) .

Pre-production Stripping #700,00

Contingency  plan # 5,000,000 to convert to manual mining 

  -----------

Total Capital Costs

Article compile by: staycool

Contact:+2347068892427

   Gemstonoe Chain in Nigeria

Sustainable Frame Work for Financing Mining Sector of Edo State

The availability of immense solid Mineral  in Edo is no longer in doubt as we have proven reserve of Dolomite, limestone, feldspar, kaolin, Granite , Gold , Sand among others. This becomes more authenticated when Journal of National research Volume 3, No.11 published in 2013 shows the distribution of limestone, dolomite and Marble within Akoko Edo, okpella, igara, atte, Etsako to mention few geographical locations. This was the view point discribled by Gov. Godwin Obaseki in December 18, 2016 on Nigeria Observer news that "Edo solid minerals can generate more revenue than oil".

 But to strengthen the investor in the mining industry require a clear Road Maps for a sustainable funding. 

Who are the Miners?

A Miner is someone or a company having relevant Mining Rights, permits or licences from the Federal Government that are currently working no matter how small the level of operations is. Hence this Narrow our search to active Title Holders and not Lease Speculators or illegal Miners. In providing the Frame Work, the Title holders in Edo State is about 45 Companies. Hence ,  A Funding scheme will be Target at this Audience. 

Most Mineral Title holders are willing to change this country economy story if they have the required equipment (Mining weapons).  Mining as a sector depends on equipment and machinery, most operations in the mine from development operation to haulage and mineral processing requires earth working machines. As there is little to what local tools and labour intensive mining operation system can go in Mineral exploitation. Just as Federal government is interested in switcheroo economy change from solid miners, The mining sectors are also willing to deliver only if government can save them from the hinge of machinery limitation. Thou past government administration had been coming up with funding ideas through BOI and other loan system but it obvious that past era loan system had fail to metamorphose mining sector for good. This is because most productive Mineral Title holders are not getting what they need from the loaning system, what they need is beyond huge loan. Huge loan will be limited to the mining lions (larges scale miners LSM) whereas the cats (small scale miners SSM & quarry miners QM) who are the largest and the highest producer will have no benefit at all.

Giving loans is not a bad idea, but loan is only limited to the beneficiary unlike buying equipment and machinery for regional Mining Association. This will be a unanimous advantage as individual Miner/Mineral Title holders can easily hirer the equipments at subsidize low rate.

In doing this,

1. Income from equipment will stabilize the Mining sector and MAN body,

2. Miners have an increase in production which will generate more revenue to Government in terms of Royalty since royalty and tax paid is directly proportional to miners production rate,

3. It will also be a means of employment generation as larger mine will be developed and lease holder will maximize the entitled working space instead of creter working space exploit by manual tools,

4. Private equipment hiring will be restructured and normalize under competition influence, this will also be an advantage to Miners.

The funding are suggested to be in the following ways

1 Soft Loans for Miners

 2. Acquisition of Mining Equipment 

Excavator cat330 BL 3 PC's

Dozer D8k 2pcs

 Drilling Machine,

 Atlas Copco ROCL8,

 2pcsPortable Compressor 10pcs

Proposed Equipment control System (ECS)

 All related suggestion like this had always been crushed on the base of poor maintaince and incompetent/good management of the equipment. To curb this challenge, the idea below was suggested as the greatest way to synergistically avoid the idea limitation.

A Team suggested to be called Equipment Provider (EP) will be created under the auspices of Miner Association of Nigeria Edo State Branch. The team will be in charge of equipment hiring, maintenance and mobilization regulation to Miners at a reduced Rates.

Concluding remark

Miners can always exploit the ore Ultimately when the required machines and equipments are available. Private equipment hiring are limited, available machines are not accessible and old , how can mining sector consisting of more than 45 plus mineral title holders cope with 3 or 4 excavator? The equipment will be over use, miners operation will be limited to what manual labor capacity can do. When will Nigeria solid Mineral break record with low working capital and labour intensive system? The problem is not Mineral deposit unlike others who go hundred meters into the earth crust to get the mineral, we have deposits as outcrop. We are blessed with shallow overburden deposit, some are even zero overburden but still, country like South Africa known for underground mining still surpass us. 

 We have identify the problem now and also provide the necessary solution to cause change. God bless Nigeria, God bless MAN.

By: Engr Fatai Jimoh

DREAM THE FUTURE NOW: JOB VACANCY MASTER KEY

This article will dendriticaly explain how someone can add value to himself,  how to become the best in your field of study and get the job of your dream.

It not new that securing job nowadays is very difficult for fresh graduates and that only those flexible enough with content rich brain can secure for themselves good job even after 4/5 years of study. Is not by grade or certificate now, the new currency exchange in labor market for job is value the son of knowledge. Thanks to God almighty, the giver of all wisdom, wisdom is the principal thing, in all your gettings get wisdom and knowledge.

Actually, most Mining Engineers are paid base on productiveness, efficiency and knowledge inbuilt. This fact can't be compromised, how good is it if you can be sincere with yourself as a student reading this article or as a graduate reading this article, ARE YOU EMPLOYABLE? CAN YOU ACTUALLY DELIVER BY DEFENDING THE CERTIFICATE YOU CARRY??

 Job interview is a package put in place by Company MD, HRM, CEO, COO to weigh each applicants.

All applicants on a normal level have Certificate which makes them qualify as an applicant.

But all applicants are not of the same capacity when been examined.

Why?

The answer is that,

The content in you will determine what you weigh on the interview weighing balance.

The truth is that you can not weigh more than what you carry, you can not have more than what you search and you can't search more than what you know about something.

How will you know???

Knowledge is power because it is informative!

"You know by reading or by listening"

Delineate your chance of getting job by getting value, search for value and add as much as you can to yourself. How can I get, add and build value to myself?????

This is the greatest question, I will have like to get answer to when I was in Senior secondary school,

If I had such opportunity to get answer to this question before my admission into polytechnic then it would have been of great advantage.

Because, until you know how to add value to your certificate (first class, second class, third class, or pass) you will remain useless even when school certificate certified you to be competent, whereas drop out are making cool money from your field of study.

Value makes first class student worthless and useless in a company whereas *pass* is taking led of high position. Value makes an agricultural Engineer held a mine company where the so called Mining engineer is a haulage manager.

Value makes civil engineer the MD of a quarry where a valueless mining Engineer take charge of audit unit.

How can I get value, how can I build value and how can I sustain value?????

.....Value Is the present worth  of a thing, lets ask ourselves  what is our present  worth...

The first thing to do is to identify the real aspect of your field you will like to practice after graduation.

For example,

Mining engineering is aution into two:

1.Surface mining

2.Underground mining

For surface Mining there are different duties and job description

1. Solid mineral sector

2. Oil and gas sector

I like teaching this because, this is the foundation to getting knowledge.

The settling velocity of knowledge is a function of passion.

But higher institutions course prospectus will not limit you to your passion but will only point you to your passion without stopping at the nude where you can just go for it. The unfortunate thing is that, we can't change this.

But we can fold the influence such that the limbs dip towards our passion.

 Let navigate into the  selection of path now. Mining as a field of study is broad, You can't do everything and practice all.

In versity, you will only be Introduced to all, while you practice one.

It becomes difficult to perform well sometimes for some people because, as a student for example I may have passion for oil and gas and now I find myself in FUTA, department of Mining Engineering.

To me, I love oil and gas!!!!

But for FUTA you must go through all courses which is up to 80+ even if you will only do two major course (MNE403: introduction to petroleum and MNE 505: Petroleum reservoir Engineering) which are the only aspect you like to feed on.

The best thing to do is this:

At start,

1. Get your core aspect well.

What I mean is this, try understand which company you will like to work after school and what you will like to do in the company.

This is it:

If I am a mining Engineer, I have passion for solid mineral sector, I like to work with Dangote, I love quarry work, I have passion for dilling and blasting.

 Above all, I think my core area is drilling

 Under drilling, you need to add value to yourself on anything relating to:

1. Type of drilling

2. Drilling equipment (for your case now surface mining equipment and those used by Dangote and related companies)

3. Drill pattern and blast design

4. Any other thin on drilling as applicable to Dangote competitors

This is not all, For you to add concentrated value and not gangues/tailings value.

Go online and download the requirements for Drilling Engineer job in Dangote related companies.

In any job description, there is always requirements Get this,

For example

Dangote or BUA requires the knowledge of one software for you to apply as a drilling Engineer.

You don't owe Dangote or BUA anything than to go online study the softy now and have the idea even if you can't get the set up due to high capital require to get it's product key.

Never sit down and feed on handout alone.

Most mining companies live on past experience and idea.

I think, it's time we change this ideology.

Nigeria mineral sector will never develop until they give room for change in old age approach.

You tell them 2020 principle, they will bring out 1950s class note whose principles, model and laws had been modified since 1980.

Start building your career now, fast forward you life now, check those things you will be lacking in the future and learn them now.

STOP WASTING TIME, STOP PROCASTINATING...

This is the conclusion of all, that tomorrow is having enough burden available for you to bear, prolonging those burden you can bear now to tomorrow is a yoke already!

There is a saying that, "The Best way to predict what the future will look like is to create one now".

Nothing is to difficult to navigate through if you have the compass, the issue is not lack of job, the issue is lack of valuable graduate who can make impact. Don't stop at your yesterday knowledge, get more and more.., don't wait till you join the labour market where thousands are searching for job, start creating one for yourself now, you will be extraordinary if you get yourself familiar with your Field odour now, if I am now a graduate, what will be the different things i can do to a company that will make them find intereste in me??

Will it be my certificate?

My dressing to the interview?

My connection ?

Many have all these but still using their first class brain to teach in secondary school, you couldn't get the job because you don't meet their standard, you will never get it because you refuse to standardise your certificate.

Is never to late to open and close your door! Taste for it and go for it now..

Above all, put GOD first, HE give information and direction to those who trust in HIM.

Thanks so much

Follow me to get update on my new post.

Are you confused on How to Get what your passion is? click here to learn the ways to find your passion

The mystery of Mining engineer Tools: Drilling and Blasting

 I will be sharing knowledge on most important aspect of Mining Engineering, which is Drilling and blasting.

 Actually, I always considered this as the most important aspect because as a Mining Engineer this is our tool, this is the only aspect that other Engineers can never share with us as a Miner.

This aspect is wide and extend to various other Fields.

Some of which are:

1.Petroleum in terms of casing perforation, Exploration (seismic survey) among other applications

2. Civil engineering works in the aspect of road construction ( road obstacle rock fragmentation), subsurface liquidification/compaction to mention few.

3. Borehole drilling: most time during Borehole drilling bed rock encountered are fragmented by blasting.

This is just few out of the application of drilling and blasting in other Fields.

What is Drilling?

Drilling is the creation of artificial hole into rock by man controlled or automated machines without the admittance of man in the hole. Most mining Engineers define drilling from their field perspective as: "Creation of artificial cavity into insitu rock outcrop or Boulders mainly for the placement of explosive and other blasting agents". This definition as I had earlier said is from the perspective of a Mining Engineer, because generally speaking drilling is not only carried out for blasting operation only. Drilling can be done for other purposes like; Tunnel boring using TBM, shaft boring using SBM, Raise boring using RBM, drilling can be done for mechanical   purposes(riveting, bolting among others), drilling can be done for underground wall and roof support purposes,to mention few.

There are basically four method of drilling but not limited to these four.

1. Rotary drilling

2. Percussive drilling

3. Rotary percussive drilling

4. Thermal drilling.

We have other special drilling methods like seismic, chemical drilling methods

 Drilling for Blasting is base on the rock drillability.

This is the ability of the rock to allow the   ease penetration of the bit during Drilling. This drillability is a function of the rock strength, grain size, grain arrangement, rock type. Drilling operation by rotary method involve the advancement of a rotating bit mounted on a string into the rock. The rotating bit cut the rock grains and crush it as the bit advance.  In percussive drilling, the drilling principle is base on hammering of the bit by a heavy load.This method is use for soft rock drilling, it slow and energy consuming. This method was earlier uses to drill the first oil cat well and is also employed by the old men in drilling water well in  sedimentary environment for water. The combination of the principle of both percussive and rotary drilling techniques is know as rotary percussive Drilling method. This method tend to be more efficient, as the drill bit rotate down the hole, the hammer impact compressive load on it.

This will takes me to explain the principle behind rock drilling.

How is Drilling achieve in a rock?

 Before I explain this, I will like to mention some type of drilling machines and also mention some of the most important part of a drilling machine. Examples of a Drilling machine are; wagon drilling machine, jumbo (underground), jack hammer among other machines.

The important part of a Drilling machine are; 

1. Drill: This supply energy to perform the drilling (called energy supplier or source)

2. Drill string/pipe: usually hollow pipes made of high strength metal. It perform three main function, 1. Transmit the energy from the rotary table to the drill bit, 2. Transport drilling fluid to the hole bottom, 3. Help in advancing the drill bit as the drilling depth increases

3. Drill bit: This is the energy applicator, this ultilize the energy transmitted by the drill string against the stability and the initia of rock grains to bore hole of define circumference in the rock in contact. This so called bit is design such that it has all the strength, shape, structure and other properties required to download negative energy into the rock grains and weaken it for hole formation. Bit is usually of different type base on cost, material use, shape & orientation e.t.c.Some examples of drill bit are the; cone bit, drag bit, to mention few. 

The mechanism behind drilling is simply explained in three steps:

1. The drill bit rotate and impact energy on the rock matrix, 

2. The rock grains matrix loss strength and become weaken as soon as the impacted energy is greater than their grain internal resistance strength.

3. As soon as the rotating/impacting energy of the bit increases to the rock breaking point, Micro fractures develop within the grain matrix structure either intergranularly or intraganularly.

This energy level at which the rock grains fractures and loss stability in mineral processing is called the *work index*. Remember, I only mentioned three important part of the drilling machine, there are many other parts like, rotary table, collar, control board, air hose, among others. In rotary percussive drilling machine the drill system can have it hammer mounted in two ways:

1. Surface mounted 

2. Down the hole DTH hammer

Surface mounted, the hammer is located above the drill rod. The percussion load is transmit through the drill string to the bit. The main disadvantage of this is that, most of the energy supplied by the hammer are been lost during transmission, only less amount is delivered to the drill bit to do work. The energy can be lost by vibration, heat, among other ways. For DTH, the hammer is place directly above the drill bit the energy is supply to the bit directly as the hammer hit the bit. DTH is also called ITH (in the hole). 

Before drilling operation is carried out, drilling is planned. The structure and the arrangement of the hole is design. the hole parameters design are; burden, spacing, hole depth, drill pattern to mention few.This design is very important, as it affects the blasting output. Poor drill design result into production of oversize, and less optimum size. For the seek of year one students who will be resing this article,  I will give definition to some terms now.

Note most of my definition are from my practical view, they tend to make you understand what I am talking about clearly.

Note them all, you may not find such in any textbook.

Some important definition use in drilling And blasting

I will give some on Drilling now, and for the blasting lecture I will give that related to Blasting

1. Burden: this is the distance between two rows of hole. It also define technically as the distance between the drill hole row to the free face.

2. Spacing is the distance between two adjacent holes in the same row

3. Stemming length: the length of the drill hole filled with cutting materials to confine explosive charge in a hole.

4. Subdrill: the extra hole length drill beyond the bench level to provide base for the bench floor

5. Bench height: is the maximum drill height per blasting. Is also the vertical distance between bench Crest and toe

 6. Drill pattern: is the arrangement of holes on the bench floor.

7. Free face: this is the open surface that form the pit or mine face.

8. Drill cuttings: this is the rock particule cut by the bit as it advance into the rock. 

9. Drill fluid: This is liquid, gas or mud use during Drilling to ease penetration, lubricate drill system and also remove cutting among other functions like hole wall stabilization.

There are other terms, but with this you have the required basic knowledge needed to know about Drilling.

 Drilling pattern use depend on the purpose of drilling.

Drill done for developmental purpose are carried out to:

1. Collect sample

2. Reserve estimation

3. Grade determination

4. Exploration generally.

Has different pattern compared to that carried out for blasting purpose. Developmental Drilling pattern can be systematic, regular, irregular pattern among others. But for Drilling carried out for blasting the pattern can be:

1. Square pattern: the pattern in which the burden and spacing is the same.

2. Rectangular pattern: in this pattern, the spacing is greater than the burden by 1.45-1.55 depending on the rock strength.

3. Staggered pattern: in this the spacing is greater than the burden by 1.1-1.25

The type of drilling pattern use depend on the rock strength and the rock blastability. The drill parameters affect the blast output so much as the fragmentation depend vividly on this parameters.As we all know that, the main aim of Mining is to make profit. The downstream operations like crushing, grinding, separation/screening depend on the fragmentation of the rock. Poor fragmentation apart from affecting g downstream operation, it also affect loading operation and haulage operation/haulage cycle also know as fleet design. Fleet design is mainly on the modification of haulage operation in the mine so as to achieve maximum efficiency, also to avoid haulage and loading equipment under usage and over usage. But before I start the next lecture, I will talk on how to design a Drilling operation for specific hole diameter.

 As a Mining Engineer, knowing this design alone is a tool for you, during job interview as a blasting Engineer. I will also, Mention some software you can learn on which are use for Drilling and blasting optimization.

I will talk on Kuznetsov, rammler and Cunningham fragmentation model both modified and original model.

 more in the next post
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