ASH HANDLING SYSTEM (MECHANICAL)

graphic display] to be provided by the ash handling system

supplier.

d.

Bottom Ash Hopper Local Control Stations: Provide a wall mounted,

NEMA [_____], control station at each bottom ash hopper with front

access door, lock, circuit breakers, selector switches, lights and

pushbuttons.

(1)

Selector Switches:

(a) Crusher: three position switch, "Reverse

(momentary)-Off-Forward"

(b)

Rotary Valve Intake:

two position switch "Open-Close"

(c)

Vertical Lift Door:

position switch "Open-Intermediate-Close"

(2) Emergency "Stop" Pushbutton, for clinker crusher, with manual

reset.

(3)

Indicating Lights:

(a)

"On-Manual"

(b)

"Crusher Stalled"

[2.12

ASH HANDLING SYSTEM (MECHANICAL)

**************************************************************************

NOTE: Designer shall select type of ash handling

system most suited for each project. For plants over

4 kg per second 31,500 pounds per hoursteam

ultimate capacity use a pneumatic ash handling

system. For plants under 4 kg per second 31,500

pounds per hour steam ultimate capacity use a

mechanical system. Refer to NAVFAC Design Manual

DM-3.6, Section 5, paragraph 4d for design criteria.

**************************************************************************

NOTE: Choose this article, paragraphs and

subparagraphs or the article, paragraphs and

subparagraphs above entitled "Ash Handling System

(Pneumatic)."

**************************************************************************

NOTE: The designer shall perform an economic

analysis and make a technical evaluation to

determine the degree of sophistication of the

mechanical ash handling system. Preference should

be given to keeping the system as simple as

possible. An example of this would be an

arrangement where the plant would not require an ash

silo and ash is simply removed by the operators

raking the ash pits and shoveling the ash into

wheeled dumpsters for removal. Mechanical collector

hoppers would have ash removed by means of rotary

airlock valves dumping through chutes into

SECTION 15501N

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