silo 3 - U.S. Department of Energy

Process Description for the Silo 3 Project
Document No. 40430-RP-0003, Rev. 1
Jacobs Project No. 35H19605
September 5, 2003
2.2.3 Retrieval Bin Register (EAR-1 1-5052) and Excavator Room Register (EAR-1 1-5053)
The PVS, via the Retrieval Bin Register, collects and exhausts air from the Excavator Room
by pulling air across the Retrieval Bin. The register is normally operated only during
mechanical retrieval operations.
The Excavator Room Register, which is part of the PVS, is located near the top of the silo
wall opening. The register is used to limit contamination transfer during silo wall cutting
by capturing both saw cuttings and Silo 3 dust generated during cutting. The register can
be used to transfer most of the exhaust air associated with pressure boundary
management in the Excavator Room before opening the silo sidewall.
2.2.4 Retrieval Bin Discharge Feeder (FDR-11-5106)
The Retrieval Bin Discharge Feeder (RBDF) is a double screw conveyor located beneath the
Retrieval Bin. It consists of two 1 2-in.-diameter, variable-pitch, variable shaft diameter4,
variable-speed screws. The feeder delivers Silo 3 material to the Inclined Conveyor (see
Section 2.2.5).
During MRS operations, the RBDF, a variable-speed conveyor, controls the flow rate of
material to packaging. All downstream conveyors are single-speed, and are designed to
operate at capacities equal to or greater than the maximum capacity of the RBDF.
Accordingly, these conveyors will often be operated in a "less than fully loaded" condition
due to downturns of the RBDF. All conveyors and motors are designed to operate under
these conditions.
2.2.5 Inclined Conveyor (DFC-11-5056)
The Inclined Conveyor is a pocketed, sidewall belt conveyor that receives Silo 3 material
from the RBDF. It then transports material upward at a 70-degree angle from horizontal. I
The conveyor discharges by gravity into a horizontal screw conveyor (Transfer Conveyor,
FDR-11-5100; see Section 2.2.6). The Inclined Conveyor is a heavy-duty, carbon-steel
unit enclosed for dust control. The conveyor uses a flexible corrugated sidewall belt with
cleats to prevent fallback of material during transfer.
The Inclined Conveyor is maintained at slight negative pressure via PVS connections.
Likewise, both of the downstream conveyors (Le., the Transfer Conveyor and the Feed
Conveyor) are maintained at slight negative pressures via connections to the Inclined
Conveyor. .,
2.2.6 Transfer Conveyor (FDR-11-5100)
The Transfer Conveyor receives Silo 3 material from the Inclined Conveyor (see
Section 2.2.5) and transfers it to the Feed Conveyor (FDR-10-5102; see Section 2.1.7).
Constraints resulting from the east-west locations of key pieces of equipment create the
need for the Transfer Conveyor.
*The variable-pitch and variable-shaft-diameter features ensure material pickup along the entire
length of the Retrieval Bin.
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