GN solids control designed and manufactured slurry separation system for TBM project. GN250, GN400, GN600 is special for TBM project in Hongkong.
What is TBM?
A tunnel boring machine (TBM) also known as a “mole”, is a machine used to excavate tunnels with a circular cross section through a variety of soil and rock strata. They can bore through hard rock, sand, and almost anything in between. Tunnel diameters can range from a metre (done with micro-TBMs) to almost 16 metres to date. Tunnels of less than a metre or so in diameter are typically done using trenchless construction methods or horizontal directional drilling rather than TBMs.
Function of TBM
Tunnel boring machines are used as an alternative to drilling and blasting (D&B) methods in rock and conventional ‘hand mining’ in soil. TBMs have the advantages of limiting the disturbance to the surrounding ground and producing a smooth tunnel wall. This significantly reduces the cost of lining the tunnel, and makes them suitable to use in heavily urbanized areas. The major disadvantage is the upfront cost. TBMs are expensive to construct, and can be difficult to transport. However, as modern tunnels become longer, the cost of tunnel boring machines versus drill and blast is actually less—this is because tunnelling with TBMs is much more efficient and results in a shorter project.
GN400 slurry separation system is composed of the following items:
1 GNZS83-3 shale shaker 2sets , with 2.7m3 pyramid screen area and max 7.0G vibrating strength
The shaker screen is not same as common oil drilling shaker screen, it is a kind of slit type shaker screen, material is stainless steel wire. It can process large solids such as rocks, the function is same as scalper. But if the solids in the mud is not so large, you can change a small mesh screen so that the treatment effect could be better, so it is much flexible than scalper.
2 GNZJ83-3 desander 1set, use 3 pcs 12” PU hydrocyclones with underflow shaker GNZS83-3
3 GNZJ83-3 desilter 1 set, use 18pcs 5” PU hydrocyclones with underflow shaker GNZS83-3
5” Hydrocyclones can process larger capacity than conventional 4” cone, and it is not easy to jam the inlet of desilter. The GNZJ83-3 desilter is designed of round arrangement, the round arrangement is with compact structure and better performance than horizontal line.