Applicability of hydraulic mining

hydraulic mining

1. Applicability of Hydraulic Mining Prof S J ayanthu 113MN0473 113MN0480 113MN0493

2. Objective Control of speed and direction of the hydraulic canons Usage of this eco friendly mining at a major phase Applicability in Indian mines

3. Methodology Statistical analysis of water availability in different parts of INDIA nearer to mines and application of hydraulic mining at those places Uses high-pressure jets of water to dislodge rock material or move sediment. In the placer mining of gold or tin, the resulting water-sediment slurry is directed through sluice boxes to remove the gold

4. I t was the Russians who first reported trials of the water jet underground. Background Hydraulic Mining was developed in California as early as 1852 to direct a stream of water against the gravel bank

5. Theory Hydraulic breaking of coal at the face by high pressure water jet effected by the hydraulic monitor is the basic of hydraulic mining.The effectiveness of hydraulic monitor mainly depends upon water pressure. First of all the coal is get fractured and broken by continuous flow of water jet at high pressure. The broken Coal then transported away from the face by water and is collected at the pit bottom. The Coal and water slurry is then pumped out to the surface and then hydraulically transported to the dehydration plant where coal is separated out from water.

6. MODERN HYDRAULIC MINING High Pressures 28 ‐ 40 bar, as required by material High Pressure Pump Station constant location Water delivered by steel and flexible HP lines Process water, sea water acceptable – no grit Minimal evaporation losses Slurry can flow distances – depending on size Slurry pump station minimal moves High production per unit = low costs

7. INDIAN SCENARIO @ GOPALICHAK MINE, BCCL The compressive strength of x seam coal was over 270 kg /cm2 where 80 bar hydraulic pressure monitor was used in three different phases of trail . In first phase of trail, the pillar was split into two stooks to be recovered on retreat with monitor on either side of the stooks . The monitor failed to cut coal even up to 3 m distance and flushing of blasted coal was not possible beyond 5-6 m . There of convergence was up to 5mm ,load on support was up to 10 tons and recovery up to 40% .  

8. INDIAN SCENARIO @ GOPALICHAK MINE, BCCL Contd.. In second trial the pillars were split in three stooks of less than 5 m thickness. The proposal was to blast the coal and flush out loosened out coal by the monitor . Maximum convergence up to 102 mm and load on hydraulic prop set in different split galleries reached up to 80 tons during the trail. The level of recovery remained below 20% due to stress concentration over the stooks.  

9. INDIAN SCENARIO @ GOPALICHAK MINE, BCCL Contd.. In third trial, the panel was developed in to four rectangular pillars. In this experiment, the maximum convergence was within 12 mm The load on support was within 14tons whereas level of recovery improved to 65 %.

10. Thank you.