Impact excavation system and method with particle separation
A system and method for excavating a subterranean formation, according to which a suspension of liquid and a plurality of impactors are introduced into at least one cavity formed in a body member and are discharging from the cavity so that the impactors remove a portion of the formation. The impactors are separated from at least a portion of the fluid, and are passed to a conduit so that the impactors accumulate in the conduit before being removed from the conduit.
1 . A system for excavating a subterranean formation, the system comprising:
a body member for receiving a suspension of liquid and a plurality of impactors and discharging the suspension so that the impactors remove a portion of the formation;
a first conduit for receiving the suspension after the removal;
an impactor separation system for separating the impactors from at least a portion of the liquid; and
a second conduit for receiving the separated impactors from the separator.
2 . The system of claim 1 wherein the impactor separation system comprises a screen separation process.
3 . The system of claim 1 wherein the impactor separation system comprises a magnetic separation process.
4 . The system of claim 2 wherein the impactor separation system further comprises a magnetic separation process.
5 . The system of claim 3 wherein the magnetic separation process includes a rotary drum magnetic separator.
6 . The system of claim 1 further comprising means for washing the suspension upstream of the magnetic separation system.
7 . The system of claim 1 further comprising a demagnetizer.
8 . The system of claim 8 wherein the demagnetizer is downstream of the impactor separation system.
9 . The system of claim 1 further comprising means for controlling the flow of impactors into the second conduit.
10 . A method for excavating a subterranean formation, the system comprising:
introducing a suspension of liquid and a plurality of impactors into at least one cavity formed in a body member;
discharging the suspension from the cavity so that the impactors remove a portion of the formation;
separating the impactors from at least a portion of the liquid; and
passing the impactors to a conduit so that a substantial portion of the impactors accumulate in the conduit.
11 . The method of claim 10 wherein the separation step includes using screens to separate impactors from other particles and liquids.
12 . The method of claim 10 wherein the separation step includes using a rotary magnetic separator to separate impactors from other particles and liquids.
13 . The method of claim 11 wherein the separation step further comprises using a rotary magnetic separator.
14 . The method of claim 10 further comprising washing the suspension of liquid and impactors prior to the separation step.
15 . A system for excavating a subterranean formation, the system comprising:
a body member;
first means disposed in the body member for receiving a suspension of liquid and a plurality of impactors and discharging the suspension so that the impactors remove a portion of the formation;
a first conduit for receiving the suspension after the removal;
second means in the first conduit for separating the impactors from at least a portion of the liquids;
a second conduit for receiving the separated impactors from the separator; and
third means for controlling the flow of impactors to the second conduit so that a substantial portion of the impactors can accumulate in the second conduit.
16 . The system of claim 15 wherein the separation means further comprises screen or magnetic separation means.
17 . A method for excavating a subterranean formation comprising:
introducing a suspension of liquid and a plurality of impactors into at least one cavity formed in a body member;
discharging the suspension from the cavity so that the impactors remove a portion of the formation;
separating the impactors from at least a portion of the liquids; and
passing the impactors to a conduit.
18 . The method of claim 17 wherein the separation step includes using a magnetic separator.
19 . The method of claim 17 further comprising using a magnetic rotary drum separator rotating at a speed between 50 and 400 RPM.
20 . The method of claim 18 wherein the separation step results in impactor loss of less than 3%.
21 . The method of claim 18 wherein the conduit for recovering impactors comprises at least 97% by weight impactors.
22 . The method of claim 17 further comprising separating the impactors from the liquid with a screen separation process prior to the magnetic separation.
23 . A system for excavating a subterranean formation, the system comprising:
means for introducing a suspension of liquid and a plurality of impactors into at least one cavity formed in a body member;
means for discharging the suspension from the cavity so that the impactors remove a portion of the formation;
means for washing the suspension;
means for physically separating the impactors from at least a portion of the liquid; and
means for magnetically separating the impactors from at least a portion of the liquid and/or non-magnetic particles.
24 . A method for excavating a subterranean formation, the system comprising:
magnetically introducing a suspension of liquid and a plurality of impactors into at least one cavity formed in a body member;
discharging the suspension from the cavity so that the impactors remove a portion of the formation; and
separating the impactors from at least a portion of the liquid by a screening process.
25 . The method of claim 24 further comprising washing the suspension prior to the separation step.
26 . The method of claim 24 further comprising washing the suspension after the separation step.
27 . A system for excavating a subterranean formation, the system comprising:
means for magnetically introducing a suspension of liquid and a plurality of impactors into at least one cavity formed in a body member;
means for discharging the suspension from the cavity so that the impactors remove a portion of the formation; and
means for magnetically separating the impactors from at least a portion of the liquid.
28 . A system for separation ferrous impactors from circulation fluid comprising:
means for receiving circulation fluid from a wellbore, wherein said circulation fluid comprises drilling fluid, drill cuttings and ferrous impactors;
a separation system, said separation system comprising a screen separator and a magnetic separator; and
means for receiving impactors from the separation system.
29 . A system for excavating a subterranean formation, the system comprising:
a drill bit;
a body member for receiving a suspension of liquid and a plurality of impactors and discharging the suspension so that the impactors remove a portion of the formation;
a pump;
a first conduit for receiving the suspension after the removal;
an impactor separation system for separating the impactors from at least a portion of the liquid, wherein said separation systems includes a rotary magnetic separator; and
a second conduit for receiving the separated impactors from the separator.