US 12,343,733 B2
Reclamation of waste sand
Jukka Nieminen, Nuutajärvi (FI); and Toni Wesin, Nuutajärvi (FI)
Assigned to Resand Oy, Nuutajärvi (FI)
Appl. No. 18/689,003
Filed by Resand Oy, Nuutajärvi (FI)
PCT Filed Sep. 5, 2022, PCT No. PCT/EP2022/074583
§ 371(c)(1), (2) Date Mar. 4, 2024,
PCT Pub. No. WO2023/031452, PCT Pub. Date Mar. 9, 2023.
Claims priority of application No. 21195006 (EP), filed on Sep. 6, 2021.
Prior Publication US 2024/0408612 A1, Dec. 12, 2024
Int. Cl. B03B 1/02 (2006.01); B03B 9/06 (2006.01); B09B 3/35 (2022.01); B09B 3/38 (2022.01); B09B 3/40 (2022.01)
CPC B03B 1/02 (2013.01) [B03B 9/061 (2013.01); B09B 3/35 (2022.01); B09B 3/38 (2022.01); B09B 3/40 (2022.01)] 20 Claims
OG exemplary drawing
 
1. A method for a reclamation of waste sand comprising bentonite binder, the method comprising:
subjecting a thermal treatment to the waste sand for removing carbon and absorbed moisture from the bentonite binder in the waste sand,
subjecting a mechanical treatment to the thermally treated waste sand for mechanically separating the sand from the bentonite binder, and
subjecting a cooling effect to the sand separated from the bentonite binder, wherein the method is carried out by an apparatus comprising:
a rotating oven having a first end portion and a second end portion and at the first end portion at least one inlet configured to feed the waste sand into the oven and at the second end portion at least one outlet configured to discharge thermally treated waste sand out of the oven,
a burner at the first end portion of the rotating oven configured to heat the waste sand fed into the oven to subject thermal treatment to the waste sand to burn carbon and evaporate absorbed moisture away from the bentonite binder,
at least one lifter arranged to capture at least a portion of the waste sand fed into the oven to move with the oven on an inner circumference of the oven until the sand falls back towards a bottom of the oven, the at least one lifter also being arranged to guide the travel of the waste sand in the oven towards the second end portion of the oven and the at least one outlet at the second end portion of the oven,
a rotating drum having a first end portion and a second end portion and at the first end portion at least one inlet configured to receive the at least thermally treated waste sand into the rotating drum and at the second end portion at least one outlet configured to discharge the sand separated from the bentonite binder out of the drum, and
at least one air exhauster at the first end portion of the drum configured to cause a non-heated air flow in a direction from the second end portion of the drum towards the first end portion of the drum to cool the sand separated from the bentonite binder.