Experimentation!!! Key approach in Coal Mines of China

While the driving force of the world right now is innovation, it is not at all a common term in mining dictionary. The even rare thing is to implement these technologies in the mining industry. The adaption of technologies is very capital intensive which the mining industries would not afford to go for. Though, it is seen that in the recent decades there is a slow and steady pace of growth in adaption of technologies in the mines.

Innovations are only possible when the problems arises or to achieve high targets. Former ones are prominent than the later ones. But both need a platform to experiment to achieve it. Experiments may go either ways, the better way will be written in the books while the worst would go down as the learning for next innovation. The industries fear about the worst part which would make it liable for production loss and don't try to implement the new technology till the problem arises. In the coal mines of China, they go after the high targets creating many problems and in turn creating innovations of unimaginable scales. 

Some short anecdotes about my trip to a experimental working face in a coal mine and the obstacles in this working face. 

            When I entered the experimental panel, it was kind of odd. In all the other coal mines, I could touch the roof while here the roadway looked so big just like a tunnel in metal mines. The usual height is expected to be about 1.5 meters to 3 meters, while it would be surprising to observe a 4.5-meter roadway height in the coal mines. It may be easy to say why does that matter. The deformation observed in the roadway are approximated to be about one meter which is huge including all the available supports in the system. Now, isn't that an interesting fact which can make a person think beyond the capability of the books or the articles. 

            After a long walk of 1.6 kms, we reached the working face. The facts of the coal seam were that it was 850 meters deep, 6 meters thick and longwall mining was employed. In the longwall mining scenario, I usually go through hydraulic props which stabilize the roadway near the working face. While in this working face we were going through shields which were doing the same job. That is a good resource management and a well-directed experiment but an expensive one which can be innovated to make an efficient system. 

            The working face itself possess a greater challenge as the experiment is about extracting the whole coal seam at one go. I may have missed that the the coal seam was inclined too that makes the extraction even more challenging. This high height meant big shields which is not a common sight. They have successfully implemented the big shields but what about the loads they will be going through. How the shield should be loaded in the inclined seams and how the capacity is decided in these big heights? Which are all the questions which are still to be pursued to find the solutions and create wonders in the mining site. 

            Coal mines in China don't work when problem arises. They create a new problem which inturn creates multiple problems. This is the key approach that they are following and have been very successful so far in experimentation and innovations. 

This would be a good message to the industries in the world to not to fear about the experimentation while be determined to go into the books for key innovations not only in the coal industry but in the metal mines industry. 

Mine Rider Journey in a Coal Mine

Transportation of the manpower to the working face is one of the vital part of the mining system. The closer it is to reach the working face, better the efficiency of the people. It does not exhaust the people from walking long distances though it gets habituated after few a month (personal experience). The working time is less effected as the people can work more on the working face than in commuting. 

In the old ages, it started by going through ladders to the coal deposit through small boreholes and excavate for few meters that is short walks to the coal faces. Later, the shafts came into play. Shafts have been a game-changer for the transportation of the manpower as well as for the material. The huge demand in the recent years started making the mines exploit the resources far away from the shaft. The technology was rapidly picking up in these years and then the Man Riding Systems were implemented in coal mines for swift movement of the personnel. 

The importance of personnel energy efficiency and the wastage of working hours made the great leap towards Man Riding Systems. The conventional Man riding systems are conveyor type while the new man riding systems can be through car or trains. I would like to take you all through my Man Riding journey.

In China, everything happens unexpected. It was Sunday evening, I was roaming around the city going through the tourist places and wondering about the beautiful sites. I was very tired and the next thing after I go to the hotel, I get a call that we are visiting a mine tomorrow morning. I am like not even a twenty-four-hour notice about the event. We went near the mine site next day morning and the mine was expected to be about 850 meters deep. The main shaft of the mine went only till about 600 meters as the coal seam at that level was the key focus of the mine last few years.

They said that we need to walk about 1.5 km and I was blindly following the fact that we will reach the face as that distance would be the normal walking distance to any working face. But to my surprise, we just reached a place with large equipment’s with no power in it. The cap lamps were the only prominent lights that made us look at different things. After about five minutes, the system started working and I noticed a new system that I haven’t been experience before, “Man Riding System”.

How cool!!! I heard a lot about these systems and I was excited to ride it and was bit nervous too. The rider seats were coming up and were taking a roundabout to go down. I was the third person to board the man rider. The first person was an old guy, he calmly went to the other side of the roundabout and hold the moving rider and sat on it and was on his path. I thought it is very easy, my confidence level boosted. The second person was my friend, he was more excited than me I assume. He didn’t go to the other side of the roundabout, he sat on the rider on this side itself. The rider due to its centrifugal force hit the wall after the roundabout and his world was shook for an instance but luckily he didn’t get hurt. I lost my whole confidence and was very nervous. Next was my turn.

I tried to calm myself and went to the other side of the roundabout and waited for my rider. I was going through all the thoughts about what do if I can’t get on the rider. After half a minute, there a comes a rider from the roundabout, thinking about what to do first. I can see it coming towards me, then suddenly my instincts made me to hold the rod sit on it like me sit on a Motor Bike (Dhoom Machale!!!! Haha…). But the instant I sat on the rider, it felt more like a Bullock Cart and can serve as perfect example. The speed of the rider was about 1-2m/s and the hanging makes you feel like the bullock cart going through ditches on the road. Then came the place to get down of the rider. It is not easy to get down on a slope. It reminded me of foot boarding which is common in Hyderabad buses. I got down and ran for a meter and a half to a halt.  

 After the visit to the working face, it was the time to go again on the Man rider. Now, I was like super confident about sitting on it. But to sit on the rider when it is going up is bit difficult than I thought. I went to the place near the belt where the rider will arrive, I did hold the bar but surprising when I did my action of sitting on it, I didn’t land on it (Haha). I gave up on that rider as it went away from the place where we were. On the slope, as the rider goes up, you need to be quick to land on it as it goes up the level. I waited for the next one which is 10m away from the one that went away. I made it quick this time to land on it. The same thing was needed on the top.

This was a wonderful experience on the Man rider. The technologies I learnt in Bachelors are now-a-days common things in the mines. I hope these experiences get better and better each passing day.

Image Credits: http://www.aphmel.com/man-riding-chairlift-system.html 

One of the largest underground coal mine in China

           It was my first visit to China fortunate enough as research internship candidate. It is a very unique place especially because of the language barrier where no one knows English. Even though the younger generation is rapidly getting accustomed to English, they are still very far away from getting use to it in the normal life. The beauty of China lies in the behavior of the people where the people are too friendly. For example, if you ask for a direction, most probably they would accompany you till you reach your destination. I can go on writing about the beautiful aspects of China but I would like to mention a wonderful experience in one of the largest producing coal mines.

             China is well known for its coal mining and its technological advances in the last decade. The production in China escalated in last two decades at a rapid rate. The rate can be attributed to the increased efficiency of the coal mine productions such as huge productions from one single coal mine. You may assume what's new in it, there are huge open pit coal mines producing more than 10 MT per annum in other countries. It would be interesting to know that an underground coal mine producing 30 MT of coal per year and surprisingly, it does not stand in the top 10 on the list. It stands fifteenth on  the chart according to the annual coal production in China. The highest recorded annual coal production was 55 MT in china from an underground coal mine. So it raises a question how are they managing it?

             China has very thick coal seams and very flat dipping upto 3°-5° inclinations. The coal seam and the roof layers are such that it is favorable to longwall mining where the width of the face is about 240m and the length of the panel is about 2km with a height of 3.5m. These specifications looks like a normal longwall mine with just a height of the face higher than usual which is 2 - 2.5m. Then question arises how are they able to produce 15 MT of coal annually. Some may say there may be large number of panels running at the same time. It is not the case, there are only two panels in operation and two panels in development. Then how??

           The answer lies in the mining method "Longwall Mining with Top Coal Caving". It was a touch and go topic back in my bachelors where we studied about it but never had a practical aspect of it as we didn't have any mines with that kind of technology in my country. So how does this work?

              Remember, the coal seams here are very thick which is about 20m. The coal is excavated in the bottom 3.5m with longwall mining but the remaining coal left in the roof caves in the back of the shields and recovered by conveyor at the back. It is not a magic that it starts to cave automatically, it has certain conditions that are extensively studied before adopting this method. In this mine, all the conditions are in its favor for the application of this method. From the production rate, it is estimated that 85-90% of the coal on the top is recovered which makes a huge difference in the production. 

              Every mine has its own problems but to tackle it and forward is what makes you successful. It was a learning experience for me. Hope everyone gets to visit these mines to watch the amazing view of the mines. Below is the picture before we entered the coal mine.