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					     Use of Clean Coal Technologies to
             reduce Emissions

                          Chris Gross
                      Naushaad Haripersad
                       Mark Van der Riet
                              Eskom Holdings Ltd


                    Presented to the Fossil Fuel Foundation
Role of Southern African Coal in the Future World Carbon-Constrained Economy


                        17th November 2009

                                     1
         Eskom System

               2009 : 241131 GWh gross
 Coal
87.89%




                                         Gas turbine
                                           0.06%

                                             Nuclear
                                              5.39%
                                  Pumped storage
                                      1.15%

                                Hydro
                     Imports
                                0.45%
                      5.05%

                          Source : Eskom 2009 Annual Report



           2
         Eskom’s Changing Primary Energy Mix




                                                                             Pumped Storage
                                                                             OCGT
                                                                             Imports
                                                                             Renewables
                                                                             Nuclear
                                                                             CCGT
                                                                             Coal




           Existing base (2009)       Future capacity base (2025)

                                                      Source : Eskom Energy Planning, Nov 2009

  The proportion of coal in Eskom’s generation mix is proposed to decrease
steadily over time in favour of renewable energy and additional nuclear power
                                     3
International Coal
  Roadmapping




     4
IEA CCC Clean Coal Roadmap for India and RSA to 2030




                               Source : IEA-CCC 152, C Henderson, SJ Mills, Sept 2009

  IEA-CCC suggested targets : 90% CO2 removal,
  45% efficiency, near-zero NOx, SOx, particulates



                                    5
                Coal Roadmapping

• Technology demonstrations are essential
• There is no single technical solution for all
  countries
• South Africa has a relatively high dependency
  on coal as a primary energy resource
• Technology transfer is required to roll out
  solutions
• Eskom is developing its own Clean Coal
  Roadmap, closely aligned with international
  best practice
• South Africa is also embarking on a national
  coal roadmap (SANERI/FFF)


                       6
Eskom’s Clean Coal Program




          7
        Eskom’s Clean Coal Programme

• Improved efficiencies on existing sub critical
  pulverised coal (STEP & beneficiaition)
• Supercritical Pulverised coal – Medupi & Kusile
• Ultrasupercritical Pulverised coal - scanning
• Fluidised Bed Combustion - pilot
• Conventional and advanced emissions control - FGD
• Surface gasifier - IGCC
• Carbon Capture and Storage
• Underground coal gasification – IGCC

         IGCC = Integrated Gasification Combined Cycle


                             8
       Efficiency Improvement on Existing Plant

                P ro b a b le Im p ro v e m e n t &    A re a s

0 .0     0 .2    0 .4   0 .6    0 .8   1 .0   1 .2




                                                      D F G   (O 2 %      (E x c e s s      a ir))

                                                      R e h e a t A t t e m p o ra t io n

                                                      C o n d e n s e r B a c k p re s s u re

                                                      D F G (G O T (P a c k s , F o u lin g ,
                                                      le a k )
                                                      M a in S t e a m     T e m p e ra tu re

                                                      U n b u rn t C a rb o n in A s h (V o ls         /
                                                      E x c e s s A ir / P F F in e n e s s )
                                                      R e h e a t S te a m     T e m p e ra tu re

                                                      M a k e -u p w a t e r

                                                      T u rb in e D e t e rio ra t io n

                                                      W o rk s   P o w e r


                                                      F e e d W a te r T e m p e ra t u re

                                                      W F G L o s s      (T o t a l M o is t u re in
                                                      C o a l)




                                   9
             Benefit of Efficiency

                                          • Efficiency is
                                            inversely
                                            proportional to GHG
                                            emissions
                                          • Eg. an efficiency
                                            increase from 36%
                                            to 50% represents a
                                            decrease in CO2
                                            emissions of 25%




Source : IEA-CCC 150, D Adams, Jul 2009



                           10
        Eskom’s Clean Coal Programme

• Improved efficiencies on existing sub critical
  pulverised coal (STEP & beneficiaition)
• Supercritical Pulverised coal – Medupi & Kusile
• Ultrasupercritical Pulverised coal - scanning
• Fluidised Bed Combustion - pilot
• Conventional and advanced emissions control - FGD
• Surface gasifier IGCC - pilot
• Underground coal gasification – IGCC
• Carbon Capture and Storage

         IGCC = Integrated Gasification Combined Cycle


                             11
        Eskom’s Clean Coal Programme

• Improved efficiencies on existing sub critical
  pulverised coal (STEP & beneficiaition)
• Supercritical Pulverised coal – Medupi & Kusile
• Ultrasupercritical Pulverised coal - scanning
• Fluidised Bed Combustion - pilot
• Conventional and advanced emissions control - FGD
• Surface gasifier IGCC - pilot
• Underground coal gasification – IGCC
• Carbon Capture and Storage

         IGCC = Integrated Gasification Combined Cycle


                             12
                                  UCG-IGCC Basic Principles
Surface Plant (incl. IGCC)
commercially proven with
other gases




                                                                                     Gas out




UCG is a process where air                   Air in
is injected into the cavity,
water enters from
surrounding strata, and
partial combustion and
gasification take place at the
                                                                                    UCG commercially proven in
coal seam face after ignition.
                                                                                    Former Soviet Union (FSU) –
The resulting high-pressure
                                                                                     needs proving in RSA on
gas stream is returned to the
                                 Graphic Reference : Science & Technology Review,       commercial scale.
surface, where the gas is
                                 Lawrence Livermore National Lab, USA, April 2007
dried and then combusted in
a high-efficiency power
station to generate
                                                          13
electricity.
       Eskom Strategic Drivers for UCG-IGCC


1. Security of supply             Baseload option           √
                             Lower C02 Emissions (25 %
2. Clean energy              lower than super critical PF
                                        coal)
                                                            √

3. Flexibility                  Modularity, lead time       √
                                 Potentially 350GWe         √
4. Utilize Unminable Coal
                                Better utilisation than
                                conventional mining         √
5. Lower cost option             Competitive R/MWh          √
                        14
                                LCA Comparative Emissions

                 1000                                                                                          4.0




                                                                                                                     NOx/SOx/Particulates kg/MWh net
                  900                                                                                          3.5
                  800
                                                                                                               3.0
CO2 kg/MWh net




                  700
                  600                                                                                          2.5

                  500                                                                                          2.0
                  400                                                                                          1.5
                  300
                                                                                                               1.0
                  200
                  100                                                                                          0.5

                    0                                                                                          0.0
                          Conv PF       Super PF         Conv IGCC UCG-IGCC Nat Gas CC

                               CO2                NOx                SOx                 Particulates
                              Data Reference : Australian ACARP Life Cycle Assessment (LCA) study, Case Study B20, June 2002


                                                   15
                 The only cleaner coal-based technology is the developing ultra-supercritical PF
        Eskom’s Clean Coal Programme

• Improved efficiencies on existing sub critical
  pulverised coal (STEP & beneficiaition)
• Supercritical Pulverised coal – Medupi & Kusile
• Ultrasupercritical Pulverised coal - scanning
• Fluidised Bed Combustion - pilot
• Conventional and advanced emissions control - FGD
• Surface gasifier IGCC - pilot
• Underground coal gasification – IGCC
• Carbon Capture and Storage

         IGCC = Integrated Gasification Combined Cycle


                             16
              CCS &CO2 Mitigation Options

Pre-Combustion
Ø Coal beneficiation,
Ø Fuel switching.



                  During Combustion
                  Ø STEP – efficiency optimisation
                  Ø Biomass co-firing
                  Ø Oxy-fuel firing
                  Ø Higher steam cycle efficiency


  Post Combustion
Ø Amine Scrubbing
Ø Chilled Ammonia
Ø Biomass & coastal coal


                                  17
       Eskom participates in the CSLF, and the National CO2 Storage Atlas
                                   Thank You




                                               Eskom’s Ankerlig OCGT
Majuba UCG
             E class gas turbine




                                   18

				
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