SYSTEM AND MECHANISM FOR BOTTOM ASH FEED REGULATION TO A LOW CAPACITY CONVEYOR

Abstract

A system and mechanism for bottom ash flow turndown from a hopper, through a crusher, and to a conveyor, the system including a fixed flow restrictor and a variable speed side discharge crusher to modulate bottom ash flow in the absence of gate or valve flow from a hopper.

Claims

1. A system for providing the efficient turndown of high flow bottom ash from a hopper, the system comprising: a. A bottom gate having a fixed in situ opening for bottom ash to move therethrough; b. A crusher subassembly including a side discharge crusher and offset conduit, the side discharge crusher receiving bottom ash from the bottom gate and pumping the bottom ash through the offset conduit; and c. A conveyor subassembly for receiving the bottom ash from the offset conduit and transporting the bottom ash away from the hopper subassembly.

2. A system for providing the efficient turndown of high flow bottom ash from a hopper, the system comprising: a. A bottom gate located on the hopper, the bottom gate having a fixed in situ opening for bottom ash to move therethrough; b. A crusher subassembly including at least one fixed plate and a crusher, the at least one fixed plate receiving bottom ash from the bottom gate and being generally orthogonal to the ash flowing from the bottom gate, wherein the at least one fixed plate redirects ash flow prior to entering the crusher; and c. A conveyor subassembly for receiving the bottom ash from the crusher subassembly and transporting the bottom ash away from the hopper.

3. A system for providing the efficient turndown of high flow bottom ash comprising fine and large ash particles from a hopper, the system comprising: a. A bottom gate located on the hopper, the bottom gate having a fixed in situ opening for bottom ash to move therethrough; b. A crusher subassembly including at least one fixed plate and a crusher, the at least one fixed plate receiving bottom ash from the bottom gate and being adjacent the crusher for reducing the fluid opening to the crusher while still permitting the flow of both fine and large particles therethrough; and c. A conveyor subassembly for receiving the bottom ash from the crusher subassembly and transporting the bottom ash away from the hopper.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] FIG. 1 shows an exposed view of an example bottom ash processing system including a side bottom crusher assembly in accord with an embodiment of the present invention.

[0020] FIG. 2 shows an exposed view of an example bottom ash processing system including a side crusher assembly in accord with an embodiment of the present invention.

[0021] FIG. 3 shows an exposed side view of a crusher assembly with an orifice plate in accord with an embodiment of the present invention.

[0022] FIG. 4 shows an exposed side view of a crusher assembly with an extended wear plate in accord with an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0023] Set forth below is a description of what is currently believed to be the preferred embodiment or best examples of the invention claimed. Future and present alternatives and modifications to this preferred embodiment are contemplated. Any alternatives or modifications which make insubstantial changes in function, in purpose, in structure or in result are intended to be covered by the claims in this patent.

[0024] FIGS. 1 and 2 shows a bottom ash processing system 10 in accord with an embodiment of the present invention. The system includes hopper 20, crusher 40 and conveyor 60 subunits. The 20 receives bottom ash from one or more boilers (not shown), which are displaced through a bottom gate 22 (typically an 18 or 24 square opening). The bottom gate preferably does not modulate or otherwise close unless the machine is turned off (e.g., for maintenance or cleaning). The bottom ash then empties into a crusher subunit 40 where the larger particles are reduced in size prior to the bottom ash being placed on a conveyor 60 for further processing (e.g., dewatering) and transport or storage. The crusher 40 includes a variable speed controller to adjust the flow rate of bottom ash therethrough. This control mechanism, in effect, turns crusher 40 into a pump so as avoid overfeeding of the conveyor 60.

[0025] As shown in FIG. 2, a first preferred embodiment of the crusher subassembly 40 includes a diluting spray pipe 41, a seat 42, a rail 44 and a portal 46, and crusher 48 and an offset conduit 50. The diluting spray pipe 41 is preferably located between the hopper and the rest of the crusher subassembly. The flow of the diluting spray pipe 41 may be adjusted so as to provide a coarse ash feed control. The seat 42 and rail 44 mate with the hopper 20 and the bottom gate to enable a mating arrangement between the hopper 20 and crusher 40 subassemblies. The portal 46 enables an operator to manually clear any occlusion in the bottom gate with a rod or similar tool. The crusher 48 includes a series of rotating teeth 49 to capture, grind and break down the larger bottom ash particles for better processing. In this embodiment the crusher 48 is a side discharge crusher which pushes the bottom ash in a horizontal direction (relative to ground) and into the offset conduit where the bottom ash can be picked up by the conveyor subassembly 60 for transport and further processing. The crusher has a variable speed control capability which acts as a fine control of the feed rate operating in conjunction with the dilution spray pipe 41 to control the feed rate to the conveyor subassembly and enable continuous operations. In this way, the configuration of the crusher subassembly using the side discharge crusher receiving and controlling the bottom ash in effect turns the subassembly into a pumping device providing turndown for the higher flow of bottom ash received from the hopper 20.

[0026] As shown in FIGS. 3-4, other geometries of fixed flow restrictors can be used with the crusher subassembly 40 to enable similar turndown functions in bottom ash processing between the subassemblies. For instance, as shown in FIG. 3, the crusher subassembly 40 can employ an orifice plate 54 decreases the inlet of the crusher 48, thus enhancing the turndown of the ash flow received from hopper 20. This greatly decreases the flow of fine bottom ash particles through the back of the crusher 48, but still allows larger particles into the crushing zone. Still another option is shown in FIG. 4, wherein an extended wear section element 56 is extended next to the crusher 48, thus moving the crushing zone to the top of the crusher from the bottom of the crusher, thereby allowing the crusher 48 to crush and meter so as to slow down flow.

[0027] The above description is not intended to limit the meaning of the words used in the following claims that define the invention. Rather, it is contemplated that future modifications in structure, function or result will exist that are not substantial changes and that all such insubstantial changes in what is claimed are intended to be covered by the claims.