OPERATION OF VACUUM SYSTEM

3.6.1 Start Vacuum System

To arouse a vacuum in the evaporator used a tool called Ejector.

If Black Liquor is charged each effect and Cooling water was circulated on Surface condensers and after / inter condenser, the vacuum system can be operated with the following procedures:

1. Open the manual valve inlet Primary and secondary steam ejector

2. Open the manual valve inlet vapor ejector Hoging

3. Open the manual valve inlet steam ejector hoging

4. Close bypass valve vacuum breaker

5. If the vacuum in the PF-6 has been achieved -700 mbar Hoging cap ejector and ejector Primary and secondary roads remain

Figure 3.13 Operation of Vacuum System

3.7 Procedure Start Evaporator

1. Charging Black Liquor into effect

• Start the pump WBL Feed

• Set the flash tank feed flow to approximately 30% of the design by adjusting the control valve WBL feed

• Raise the level of PF-6 to 80% and then start the circulation pump PF-6.

• Start Transfer pump PF-6 and set the level controller with set point 50% of auto

• Then Black Liquor will go to PF-5, and repeat the procedure as PF-6 for each effect 5, 4 effect, effect 3 and effect 2,

• If the Black Liquor has reached PF-2, select the PF1 sequence (eg ABC) and the valve-open valve in accordance with the order of sequence.

• Start Transfer pump PF-2 and set the level of 50% Auto

Figure 3.14 Cycle Black Liquor from WBL tank to the PF-2

• Raise the level of PF-1A to 80% and then start the circulation pump PF-1A

• Setting the level of PF-1A 50%

• Perform the same procedure for filling PF and PF-1B-1C

• Black Liquor Spill circulated to the tank or tank WBL

Figure 3.15 Cycle Black Liquor on the PF-1A, PF-1B,-1C PF, PF-1D

2. Operation of Steam and Condensate LP

If the vacuum in the PF-6 has been achieved -750 mbar the LP steam to PF-1 can dibuka.dengan following steps:

1. Make sure the vapor control valve to open ABC PF-1 to approximately 50%

2. Make sure the condensate level pot for PF-normal 1ABC Auto position set point 50%

3. Make sure the condensate flash tank pump ready and conductivity meter to function properly

4. Open the Manual Valve LP steam for PF-1ABC 100%

5. Open the LP steam control valve for PF-1ABC approximately 20% or LP steam flow set around 20 tonnes for each Effect 1ABC

6. Set desuperheater control valve to the Auto position set point around 135 s / d 140oc

7. If the condensate level has appeared in Flash Condensate tank, start the pump and condensate pump control valve set to 50% of auto

8. Change the position of the on-off valve condensate to Sequence

9. If steam has entered the Effect 1 then evaporation will occur at each effect and the condensate will occur

10. If an indication of the level of the Clean condensate flash tanks have emerged, Start clean condensate flash tank pump, then set Auto level controller to position the set point of 50% and set the on-off valve to the position of Sequence.

11. Note the level on Foul condensate flash tank, if the level has emerged pump start Foul condensate flash tank, then set the level controller to Auto position set point 50%

12. Adjusts the on-off valve to the Sequence (if high conductivity will automatically go to the spill tank)

Figure 3.16 Cycle LP Steam and Condensate in PF-1

Figure 3.17 Cycle Vapor and Condensate

3. Operation Stripper

Stripper is a tool that serves to purify Foul condensate by way of separation of the gases in the foul condensate to be burned again in RB / RC.

• Operating procedures Stripper system:

1. Make sure all equipment is ready to operate on stripper

2. Foul condensate tank pump start and open the outlet valve of the field manual

3. Open the control valve to the foul condensate Striping column and set the flow to approximately 70 m3 / H

4. If the level has appeared at the bottom of the stripping column start stripping column and set the pump control valve position set point Auto with 50%

5. Open Black Liquor incoming Reflux condenser (with manual valve open inlet and outlet reflux condenser).

6. Open the control valve outlet NCG Trim condenser approximately 25% and manual valve inlet flame arresters and make sure the path is open all the way NCG NCG burner or by pass into the atmosphere.

7. Open warm water condenser inlet and outlet Trim

8. Open the LP steam or vapor into stripping column as needed or loaded with foul condensate ratio to 1:5 ton steam

9. Start pumping condensate pot if indications have appeared on the tank level and control level set to Auto position set point of 50%.

10. Set out with a press NCG NCG set the control valve