Simplifying Water Treatment Program for the Steam Generators

Transcription

1 Simplifying Water Treatment Program for the Steam Generators Fahad M. Al-Senayin Saudi Aramco/Abqaiq Plants February 2, 2011 Copyright 2011, Saudi Aramco. All rights reserved. No portion of this presentation may be reproduced, by any process or technique, without the express written consent of Saudi Aramco.

2 Definition Simplified Steam/Water Cycle Monitoring Process Outline: Simplification Reasons Simplifying Process Summary

3 Water Treatment (WT): It is a set of processes that condition water and control the water s impact on its surroundings. Definition: WT Simplification: It is a systematic approach aims to improve water treatment quality by make it s processes easier for controlling and monitoring.

4 Simplified Steam/Water Cycle: Water Losses (2) 85% Return Cond. 6 Condensate Tanks Users Boilers (12) HRSG (5) 625# Steam Water Losses (1) 15% Make up Make Up W ater (ROP) Chemical Injection

5 Corrosion Rate Monitoring Processes: Scale Density Index Quarte rly/ann ual Checks Quality Monitoring Index, CCI Out-Of-Spec Frequency Treatment chemical cost

6 Simplification Reasons: 1. Complexity of the control Out-Of-Spec frequency is high Blow down rate is high High chemical cost No automation, high human error 2. Change in water feed quality 100% make up of Reverse Osmosis 3. Reassessment of chemical additive quantities No consistent of chemical additive vs. BFW quality No consistent of chemical additives vs. steam quality

7 Objectives: Optimize types and numbers of chemical additives Simplifying Process: Maintain steam quality, reduce human interference and make cost saving Conserve natural resources, water & energy Reduce the plants environmental footprint Phases: Phase I: Data collection, analysis and startup of chemical optimization Phase II: Chemical additive reduction Phase III: Automation with Documentation

8 5 Simplification Process: Task Phase I Phase II Phase III Years

9 15% Make up Simplified Steam/Water Cycle: 6 Condensate Tan ks 85% Return Cond. Users Water Losses (2) 625# Steam Boilers (12) HRSG (5) Water Losses (1) Make Up W ater (ROP) Chemical Injection

10 WHERE? T=310 F Steam (625 psig) T=750 F Steam Turbines Deaerator (6) Polymer/PO4 DEHA Caustic Antifoam Amin e TSP (PO4) Caustic (Intermit) Antifoam Boiler (12) HRSG (5) Fin Fan T=310 F Steam (60 psig) Condensate Water RO Make-up Re-Boiler Re-Boiler Condensate Tank (6) Return Condensate Condensate Water

11 WHERE? Phase II: I: - continued Test: D.O 2 T=310 F Steam (625 psig) T=750 F Inspect SGs SDI Steam Turbines Deaerator (6) Polymer/PO4 TSP (PO4) Caustic Caustic (Intermit) Antifoam Antifoam Amin e(optional) Boiler (12) Chem. Clean Change the control Parameters T=310 F Steam (60 psig) 1.Reduce DEHA, or DEHA Feed Neutralizing Amin e if n eeded Optimize Neutralizin g. Amine HRSG (5) Calculate COC 2.Elimin ate DEHA Condensate Water Switch Polymer/PO4 HRSG to TSP Caustic Caustic Antifoam Antifoam RO Make-up Fin Fan Re-Boiler Re-Boiler Test Condensate for: Condensate ph, Fe, Cu, D.O 2, TOC Tank (6) Return Condensate Condensate Water

12 Main Tasks for Upcoming Phases 2012, Continues: Phase III: Automate testing of steam/water and feed of chemicals ETC: 1 st Q 2012 Develop a training program ETC: 2 nd Q 2012 Exchange results with others ETC: 2 nd Q 2012 Update the Water treatment contract conditions of APOD ETC: 3 rd Q 2012 Utilize applicant software to predict/simulate cases in W/T ETC: 4 th Q 2012

13 1. Save natural resources (gas and water) Summary: 2. Save $0.3MM annually on chemical costs. 3. Make chemical control easy through simplifying treatment 4. Align water treatment with International Standards 5. Transfer valuable knowledge and hands-on experience

14 THANK YOU Questions?

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17 Outcome of Phase I 2010: Better stability of control with TSP at all HRSGs 98% of survey analysis results are within spec Steam quality is with spec with no sign of carryover Tangible cost saving was $22 M in 2010

18 Corrosion Rate 2010:

19 Out-Of-Spec Frequency:

20 Annual Cost 2010:

21 Chemical Index :

22 Chemical Cost Saving in Phase I: Area 1 South Steam Plant 2 HRSG of NGL, Plant #499 3 HRSG of Power Plant Action Optimize Amine (Morpholine) addition Change the scale Inhibitor type from Polymer/TSP to TSP Actual Cost & Saving ($/Y) Before After Saving 43,000 33,444 9,556 7,132 2,101 5,031 10,698 3,152 7,546 Total Cost $ 22,133