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Some Important Terms

Adit :- It is a type of nearly level roadway, driven to access a deposit which is at the higher level than the ground surface. Overburden :- The valueless rock body covering the mineral up to the ground surface is called Overburden. Chute :-It is a narrow passes from which the broken ore is loaded in Mines cars. Country Rock :- The rock which contains the ore body, the hanging wall and the foot wall forms from the country Rock. Hanging wall :- It is the roof of bedded deposit. Foot wall :- It is the floor of bedded deposit. Exploration :- The searching of mineral and gaining the knowledge of shape, size, position, and value of an ore body. Heading :- The driving of roadway in any part of U/G mines, mainly in development stage. Level :- A approach to the mineral bed by driving a horizontal roadway by branching the shaft, called level. Shaft :- It is a inclined or vertical entrance to mined out the economical deposit.

Flame Safety Lamp

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Before knowing the types of flame safety lamp, we should clear a question that why we are using this......? The answer is here that it cures the problem called firedamp explosion. *Sir Humphrey Davy was the first man to create a revolution of the development of Flame Safety Lamp(in 1815). The lamp light was very poor as that was surrounded by fine was gauge.                              Davy's Lamp Second Development The second development was in the mid nineteenth by Dr. Clanny. The change made by him was that he put the wire gauge over the glass. Due this the light inceases tremendously but still the lamp was not safe in strong explosion of firedamp mixture(in the lamp). Third Development The third development made by Marwar he provide a concept that was bonnet around the wire gauge also introduce more than one wire gauge.Holes at the bottom of bonnet. This is the basis of modern design of Flame ...

Testing of Gas by using Flame Safety Lamp

We undergoes two types of tests for the detection and estimation of the presence of firedamp. They are..... 1.Accumulation Test 2.Percentage Test 1.Accumulation Test... The accumulation test is the testing of firedamp in that area which not ventilated or comparatively less ventilated (they are rising gallery, Goff, face, top most air layer and blind heading). The accumulation test is conducted by Safety Lamp with normal flame by simply holding in hand and raising upwards and the motion should be zig-zag. If it give positive result there is no need to conduct percentage test. The positive result can be identified when the flame of lamp is "jumping" or "springing". It indicates that the % of firedamp is more than 3. 2.Percentage Test.... When the accumulation test don't clearly the accumulation of firedamp, it is wise to take percentage test. This test gives more accurate knowledge about the accumulation. A standard flame is required to take percentage...

Mines gases And their Physiological Effects 2.

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1.Nitrous Fumes It gets converted in to Nitrogen oxides in presence of moisture. Source- Blasting of nitroglycerin based explosives and diesel engines are also the sources of nitrous fumes. Physiological Effects:- The presence of Nitrogen oxide in mines causes irritation of eyes, nose, throat and also to the other mucous membrane of body. Due to this the coughing and the pen is happened in chest. It has acidic nature and due this the corrosion of lungs membrane is natural. *This corrosion may lead to death. Detection:- Drager Multigas Detector detects the oxides of Nitrogen. 2.Hydrogen Sulphide It is extremely toxic even in small percentage. The sources of hydrogen sulphide Ares gob fire in coal mines(if coal contains sulphur), action of acidic water on iron pyrite and blasting in sulphur mines. Physiological effects:- At 50-100ppm:- Irrigation and inflammation of eyes and respiratory tracks. 200-700:- Causes pain in chest and throat. Dete...

Mine Gases-The physiological Effects 1

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1.Carbon Monoxide The Carbon Monoxide is very poisonous gas and it's affinity towards the Haemoglobin is nearly 300times greater than Oxygen.Even if it is present in small quantity reduces the absorption of Oxygen for the blood.It may be named as sweet poison because without the carbon Monoxide Detector no one can identify it's presence. It's increase in percentage can cause.... At following percentage effects can be identified as 0.02-Headache,discomfort and may collapse within 45 to 2 hours. 0.12-Palpitations after 10 minutes of work or 30 minutes at rest. 0.2-Unconsciousness after 10 minutes at work or 30 minutes at rest. 0.5-1.0(Death within 10-15 minutes). *Sources- Spontaneous combustion, Incomplete combustion etc. 2.Carbon Dioxide The sources of Carbon Dioxide are oxidation of Coal, Decay of timber, IC engines etc. The Carbon Dioxide when dissolve in water forms Carbolic acid.It would cause mild irritation because of the presence of water (eyes, Nose ...

Mines Gases-Oxygen Percentage|Damps|Degree of Seam

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We know that is necessary of air to take breath.As we go inside the mine,the primary importance is ventilation which means "the atmospheric air go inside the mine and by clearing impurities come out side". The general composition of air in the atmosphere is as follow 1.By Volume Oxygen-20.95% Nitrogen-78.09% Carbon dioxide-0.03% Other rare gases(including Argon)-0.93% Or less than 1% 2.By Weight Oxygen-23.15% Nitrogen-75.52% Carbon dioxide-0.046% Other rare gases(Including argon)-1.3%(approx.). :- Gassy Coal Mine (degree 2 and 3)  *In return air the constituents should be Oxygen-20.28 Nitrogen-78.90 Carbon monoxide-0.36 Methane-0.46 As the gases passes through the Mine environment many impurities mixed with the composition mentioned above and also the percentage of Oxygen reduces due combustion, spontaneous heating and human breathing. DAMP   In mines the miner faces great difficulties due to damp.We can define damp as "the impurities present a...