/1, 

JE/\ Northside Units 1 and 2 Repowering Project Rev. B 

Ash Recovery and Handling 

System Operating Procedure 06/18/01 

....... 

--

...... TUIOII'OIIl 

aLOWEQ~) 

I I : , 

I ,_· r, • .. 

Figure 1 - Simplified Ash Recovery and Handling System Flowpaths 

1.3 Ash Recovery Handling System Overview 

This section provides an overview of the Ash Recovery and Handling System by 

detailing the primary and secondary flow paths and configuration. 

1.3.1 Bed Ash Handling System Overview 

The bed ash system cools ash from the bottom part of the fluidized bed and delivers 

it to the bed ash silo where it is stored until it is removed from the site. The detailed flow 

path of the system is shown on flow diagrams ARH-FD-1, and ARH-FD-2. These diagrams 

show the arrangement of the system's major components, flow paths, and control elements 

that include: 

0 Stripper Coolers to the Bed Ash Surge Hoppers 

0 Bed Ash Surge Hoppers to the Bed Ash Silo 

Rev. 8- 06/18/01 

SOP-ARH-rB.doc 

Page 3 
JE/\ Northside Units 1 and 2 Repowering Project Rev. A 

r····················-1 

i ! --: : 

:;.~R ~ AIR HEATER i -----1 . ; 

··· ............... _.·· .... ····•· - .. ·· 

Air Quality Control System 

System Operating Procedure 

TO RECYCLE STORAGE BIN 

Figure 1 - AQCS Overview 

6-21-01 

...,... COMMON .······~J:f.~.~-~ ..... STACK -......... / \.. j \ i .... i 

\ ....... \) ...... ./ 

The detailed flow path of the Air Quality Control System is shown on flow diagrams 

AQC-FD-001, AQC-FD-002, and AQC-FD-003 provided at the end of the procedure. 

These diagrams show the arrangement of the system's major flow paths and components 

that include: 

0 Selective Non-Catalytic Reduction System 

0 Spray Dryer Absorber 

0 Lime Slurry Preparation System 

0 Fabric Filter (Baghouse) 

0 Constant Emissions Monitoring System 

Rev. A- 21 June,- 01 

SOP-AQC-rA 

Page 3 
JEl\ Northside Units 1 and 2 Repowering Project 

PERFORATED 

DISTRIBUTION 

PLATE 

Air Quality Control System 

System Operating Procedure 

Figure 3 - SDA Operation 

I ~ • - I r .... 

Rev. A 

6-21-01 

distribution 

The flue gas enters the top of the Spray Dryer Absorber through a flue gas 

system. This distribution system uses a perforated plate that creates a plug flow 

flue 

atomize 

gas pattern. The lime slurry is introduced into the SDA through fluid nozzles that 

the slurry into fine spray droplets. The nozzles are installed in a piping manifold 

entire 

and spaced across the top of the SDA in a pattern that causes the slurry spray to cover the 

area of the SDA. 

S02 is removed from the flue gas stream in two separate chemical reactions. First, 

shown 

the acid gases react with the calcium hydroxide in the slurry creating calcium sulfite as 

here: 

Rev. A- 21 June, 01 

SOP-AQC-rA 

Page 8 
JEl\ Northside Units 1 and 2 Repowering Project Rev. A 

Air Quality Control System 

System Operating Procedure 6-21-01 

The lime slurry system is shown in Figure 4 and in flow diagram AQC-FD-001, at the 

end of this module. 

ASH AND 

SOUDS 

FROM 

FABRIC 

FILTER 

HOPPER 

EXCESS ASH/ 

.----+ SOLIDS TO FLY 

RECYCLE 

STORAGE BIN 

ROTARY 

FEEDERS AlB 

RECYCLE 

SLURRY MIX 

TANK 

REUSE -------., 

WATER - I 

RECYCLE 

SLURRY 

STORAGE 

ASHSJLO 

~·-- . 

TANK L__:::::_,j----"1-ti*'" 

FEED SLURRY 

TRANSFER PUMPS 

AlB 

FEED 

SLURRY 

PUMPS 

AlB 

FEED 

SLURRY 

HEAD 

TANK 

TOSOA 

SPRAY 

MANIFOLD 

LIME SLURRY 

STORAGE 

TANK 

LIME SLURRY 

FEED PUMPS 

AlB 

LIME SLURRY 

TRANSFER 

PUMPS 

A1&A2 

81 &82 

Figure 4- Slurry Preparation System 

Recycle Slurry 

LIME 

STORAGE 

SILO 

TRUCK 

FILL 

LIME 

FEEDERS (AlB) 

(ROTARY AND 

WEIGHT) 

MILL PREMIX 

CHAMBER (AlB) 

Recycle slurry is un-reacted or unused lime that is recovered from the fabric filter 

and SDA hoppers and mixed with water to create a 40-45% solids slurry. Reusing the 

partially spent lime lowers the amount of fresh lime required by the sulfur removal process, 

thereby making the process more economical. The lime comes in two forms, either calcium 

oxide (CaO) collected from the combustion process in the fabric filter hoppers, or calcium 

Rev. A- 21 June, 01 Page 10 

SOP-AQC-rA 
r 

JE/\ 

TO FEED 

SLURRY 

TRANSFE----; 

PUMPS 

FROM 

FEED 

i )' tSLURRY 

TRANSFER 

PUMPS 

FROM 

REUSE 

WATER 

HEADER 

(FLUSH) 

FROM 

REUSE 

WATER 

HEADER 

(FLUSH) 

FROM 

REUSE 

WATER 

HEADER 

(FLUSH) 

VENT 

: 

Northside Units 1 and 2 Repowering Project 

Air Quality Control System 

System Operating Procedure 

FEED SLURRY 

P~1A 

N01·RAOH07 

FEED SLURRY 

PUMP1B 

N01-RA01-G08 

Figure 15 - SDA Feed Slurry System 

~ 

PENTHOUSE 

DRAIN 

Rev. A 

6-21-01 

One Feed Slurry Pump is normally in service with the other serving as a backup. 

The pumps are installed in identical parallel piping arrangements. The Feed Slurry Pumps 

are rubber lined, single stage centrifugal pumps driven by 480 Volt, 40 HP motors. Each 

pump is equipped with pneumatically operated suction and discharge valves. 

Drain lines are provided in each pump's suction header and flush water supply lines 

to each pump discharge header. The drain and flush valves operate together to clear the 

slurry from the pump and piping when a pump is shutdown. Flushing prevents the solids in 

the idle slurry pump from separating from the liquid and settling out in the bottom of the 

components. When a pump is shutdown the suction and discharge valves close 

automatically. 

Reuse Water 

The drain and flush water supply valves then open automatically to allow 

to flow through the pump and piping and drain into the SDA penthouse drain. 

These valves all operate automatically when a pump is started. The following automatic 

sequence is initiated when a pump is started: 

0 Pump given start signal 

0 Pump drain and flush valves close 

0 Pump suction valve opens 

Rev. A - 21 June, 01 

SOP-AQC-rA 

Page 33