AN OVERVIEW OF SURFACE MINE MAINTENANCE

THREE MAINTENANCE APPROACH FOR NIGERIA MINE IMPROVEMENT

INTRODUCTION

Maintenance of mine operation is important because of the need to monitor the earth response, see to the perfect working of mine plan and mine design.

Getting the Mineral extracted from the earth crust is the major reason for mining, but getting it in a safe and profitable means is the major goal.

Surface mining methods involved the extraction of shallow depth Mineral deposit through the complete removal of the overburden materials.

Developing the ore site and extracting the ore deposit using any of the previous explained methods follows stripping operation.

As the mining operation advances, the earth stress state and other redistributed forces impact the excavated region.

This will definitely require a preventative maintenance.

Below are some of the maintenance approach to ensuring a sustainable mining operation;

1. Maintenance of mine water: I understand from personal work study that Nigeria operates majorly surface mines, mostly quarrying and open pit methods. The creation of open cavity after mining provide a basin for water gathering. Such water if not properly maintained can accommodate dangerous animals, become dead trap for community people, support leaching at overflowing and also damage landscape through support flood action. 

Reclaiming mine out area with  treated mine waste or stripped materials will enhance the safety of abandoned mine area.

Major mine operations find less interest in reclamation process, abandoning the land after removing the content (mineral) is what most Company aimed at! 

This shouldn't be the case, the need for land coverage after mining is a good way of restoring the land to a useful state, Which makes it good for other purposes.

2. Mine design monitoring and adjustment: Most mine lack the ability to design and to implement the mine layout, this had led to untimely closure of quarries and mine in Nigeria and Ll around the world (especially Artisan mines and small scale mines). Putting proper design in place to account for the ground condition and current status of the environment is a good means of mine maintenance. Going by the saying that "Prevention is better than cure" preventing mine accident such as land slide, slope failure, misfire, flyrock among others is best achieved by proper design and implementation.

Mining Engineers and safety Engineers need to maintain the site design and supervise the implementation.

Below are some ways I discovered from Academia Research work and experience to maintain a typical mine slope:

1. Proper selection of bench height to avoid plan and wedge failure and other failure type,

2. Frequent checking of slope discountinuity property to avoid unnecessary movement and dislocation,

3. Proper selection of equipment to ensure good and safe working condition,

4. Proper control of mine water to avoid toe creeping and swelling,

5. Proper mine drainage system to avoid total closure or high dewatering cost,

6. Proper blast design and explosive usage to avoid blast illness ad over break,

7. Proper and accurate excavation, and

8. Frequent monitoring of Ground water and mine hydrological condition.

Maintenance of mine plan is vital to avoid unnecessary failure of mine slope, and mine closure

3.Mine Equipment maintenance: Though most Quarry operations in Nigeria and local mines in the world operate at small scale level with high level of manually perform operations. Yet, the use of equipment like excavator, payloader, crusher and the likes is inevitable. In order to ensure smooth operation in the mine, and to have a sustainable mine and environment, proper maintenance of mine equipment is very crucial. Checking from the perspective of generation of ozone layer depleting gases from poorly service heavy duty mine equipment,

Most mine lack the equipment preventive maintenance system. This result into poor production and contribution to unsustainable environment. Providing good preventive maintenance of mine equipment will not only improve mine productivity but also support sustainable environment.

Below are some suggested ways by which mine equipment can be maintained;

1. Daily check-up of equipment before work,

2. Periodic preventive maintenance,

3. Use of good condition fuel oil,

4. Proper and quick response of mine management to driver/maintenance team complaint,

5. Appointment of qualified mechanical engineer to ensure good equipment working condition,

6. Avoiding mine equipment over usage,

7. Avoid 24hours truck working without break,

8. Avoid using trucks beyond specified capacity, and many more

Conclusion

Starting the mine is not basically the problem but sustainable mine is usually challenging. Extraction of materials from the earth crust is important to human sustainability, likewise the safety of the environment and life's working in the mine and living around the mine. Maintenance of equipment, maintenance of the mine slope and operation safety is high imperative and crucial.

This will not only dictates the mine productivity but also it profitability.

Most mine get shut down quickly by surface and underground water simple because of lack of proper maintenance. Designing  good drainage and planing good water control system willo a long way to mine sustainability. Safety case when it comes to blasting is also another need to prepare for.

Blasting Operation demands full safety plan and preparation. Post blasting plan involves putting all things in place to ensure safe movement of Explosive material from magazine to the mine and proper distribution of material for each hole charging. Maintaining the magazine to avoid unwanted initiation or problem like self detonation under unfavorable heat conditions. The magazine maintenance must be such that it suit the storage condition of the explosive materials.

On site maintenance involves putting all needful in place to ensure safe use of Explosive and to avoid misfire and poor blast result. Blast ills such as ground vibration, flyrock, airblast, dust among others needs to be account for when planning the blast.

Finally, I support the safety of all mine operation, this will give hope to us and to our generation to come.

We mine to safe life and not to destroy it.

Thanks for reading

Writer

Taiwo Blessing Olamide

Giant Miner

Prospective student

Recommend me for your Research assistant

Looking forward to 

Join professor Research work 

Research interest: Rock excavation and Rick mechanics

Review of the Effect of Blast initiation Delay Timing on Blasting fragmentation

Review of the Effect of Blast initiation Delay Timing on Blasting fragmentation

By Taiwo Blessing Olamide 

GIANT MINER

INTRODUCTION

 Do you know that;

Explosive energy is higher when the shock energy supply for the initiation is high and accurate.

Also that, most mining operations uses inaccurate blast time and initiation timing. Two things affect Blasting efficiency appart from the blast parameters and rock properties.

 These are;

1. the initiation system and

2. the initiation approach. 

This article give a brief review on Professor Takis Katsabanis and Nikolaos Gkikizas-Lamptopoupos work.

Professor Takis is an explosive Engineer, lecturer in Queen's university Ontario, Canada.

Prof Takis of Queen's university Canada with one of His master's student Nicholaos Gkikizas worked on a project relating to this in 2016. The Thesis focus on examination of the effect of Time delay on fragmentation.

 The project was effectively experiments in the university Rock Excavation Laboratory under the full supervision of Prof. Takis Katsabanis. 

 The work involved two series of experiments.

First series involved tests on small scale grout and granite blocks to determine the moment of burden detachment. The instrument use for these experiments consist but not limited to strain gauge and Piezoelectric sensors, high speed camera. The result of the first series experiment shows that the time of rock particle detachment for the thesis set up is between 300 and 600 micro second. Meaning, as the Explosive shock wave fractures the rock and the gas energy perf

The major aim of blasting is to detach the rock into handable sizes, the important of studying the detachment time as indicated by Prof. Takis student was to ensure that the burden movement timing is accurately design between inter row and intra row drill holes. Each detachment time affect the fragmentation efficiency of the blasting. The major approach adopted in the thesis was to optimize the charge timing and get the detachment time right for efficient fragmentation.

The second series of the project involved blasting of a 2m high granite bench and it's purpose was to determine the hole to hole delay that will provide optimum fragmentation. Nicholaos Gkikizas worked reflect on this objective by adopting image analysis software for fragmentation efficiency examine for each delay observed. Also, he examine the produce vibration from the blast and also record the blast with high speed cameras such as Olympic i-SPEED 2 camera.

The result of the second series suggest that fragmentation was optimum when delays between 4-6 Ms were used for the experiment set up. It was also found that the moment at which gases first appear to be venting from the face was consistently around 6ms after detonation. In one of my blog article had take time to explain the concept of shock energy and gas energy release sequence during detonation. Nikolaos in his thesis indicated that the timing difference between the initiation period and gas explosion period was 6ms, this shows that from the initiation point to 5:59ms, the fracturing process was fully taking place. The crushing zone process, the tensile slabing process and the shearing.

The Research work of Prof. Takis Katsabanis student also shows that the mean fragmentation size changes with time delay. The experiment shows that the fragmentation mean size was higher at low delay timing and higher at timing greater than 8ms. Which shows that from 2ms to 8ms, the X50 is low with 8ms been the optimum delay second.

Nikolaos work also revealed that the delay timing affects the vibration level for the experiment conducted. Ground vibration is one of the most serious blast illness after flyrock. The energy distribution from explosive result into displacement of rock and earth crust material at a define frequency level. Such is also depending on the Maximum instantaneous charge per initiation. Prof. Takis student also shows that the shorter the delay timing the higher the possibility for overlaps (constructive wave interference) 6-8ms delay produces separation of pulses as indicated by the result from the vibration results.

Conclusion

This work had shown that the efficiency of blast production and safety also depends on the charge initiation and the timing allocation.

The productiveness of blasting Operation is the main aim and Target of blasting. Ensuring safety and profitability is also a great task. 

To ensure this is fulfil, there is a need for proper design and optimization of blast timing and design to achieve this great task.

Mining and safety is our main focus

Giant Miner is committed to safe mining and campaign against poor and unsafe mining. First in Nigeria and then to the whole world.

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Reference

Read full Thesis

https://qspace.library.queensu.ca/handle/1974/15321