LANXESS CO 2 Capture plant

Transcription

1 LANXESS CO 2 Capture plant * October 2015 Dawie vd Merwe 1 Title of presentation Speaker Place, date [ OPTIONAL ]

2 Lanxess CO 2 capture plant Specified Plant Parameters Latest CO 2 capture plant in region as well as Southern Hemisphere Feed gas from Sasol Gas fired steam boiler Proprietary Amine process. Captures 5 t/h CO 2, expandable to 7t/h 99 % purity CO 2 98 % overall plant availability 2 Title of presentation Speaker Place, date [ OPTIONAL ]

3 CO 2 Usage in Lanxess Chrome plant Standard Sodium dichromate Process High temperature alkaline Roasting of Chromite ore using Soda Ash to produce Sodium Monochromate. Acidification with Sulphuric Acid to from Sodium dichromate Sodium Sulphate by-product low value product or disposal Insert photo of SDC plant Lanxess Chrome Process CO 2 used for acidification Sodium bicarbonate byproduct, Calcined to Soda ash and recycled to Roasting process. 3 Title of presentation Speaker Place, date [ OPTIONAL ]

4 Original CO 2 supply Previous supply of CO 2 to LANXESS - Air Products to 2013 Basic design Feed gas from Blast furnace - mainly CO burned in boiler to form CO 2 MEA based CO 2 capture plant Low priority on energy optimization in 1996 design free waste energy Short comings Free waste energy no longer available Supply interruptions due to feed gas interruptions Major effect on LANXESS downtime 4 Title of presentation Speaker Place, date [ OPTIONAL ]

5 Alternative CO 2 supply. Possible CO 2 sources in Chrome plant Kiln off gas CO 2 volume available - sufficient CO 2 concentration - too low Oxygen concentration- too high Calciner off gas CO 2 concentration - high Oxygen concentration - low CO 2 volume available - insufficient Third party operated Coal fired boiler High SO 2 in off gas - No Reliability problems - No 5 Title of presentation Speaker Place, date [ OPTIONAL ]

6 CO 2 capture Alternative CO 2 Capture Technologies reviewed Pure Oxygen combustion Ammonia as capture medium Carbonate Bicarbonate system as capture medium Decision on way forward Combine Steam and CO 2 supply Use proven amine based CO 2 Capture Technology Highest possible availability Highest overall energy efficiency 6 Title of presentation Speaker Place, date [ OPTIONAL ]

7 Overall Project Performance Objectives Sasol gas fired steam boiler for Chrome and CO 2 capture plant Highest possible efficiency, Low NOx incorporating flue gas recirculation Capture plant capacity 5 t/h expandable to 7 t/h 90% capture rate of available CO 2 99% Purity of recovered CO 2 gas Dry compressed gas supply at bar & -40 C dew point. 98 % plant availability 7 Title of presentation Speaker Place, date [ OPTIONAL ]

8 Typical CO 2 Capture Flow diagram 8 Title of presentation Speaker Place, date [ OPTIONAL ]

9 Process Design Package Lanxess approach - Four South African Based Engineering Companies Each engineering company then approached other CO 2 technology suppliers. Fluor + Fluor Econamine Plus Lurgi + Randell Gas technology Foster Wheeler + Mitsubishi Heavy Industries Process Plant Technology + Cansolv 9 Title of presentation Speaker Place, date [ OPTIONAL ]

10 Criteria for bid evaluation Capital cost Local construction vs import Running Costs in order of impact Reboiler steam energy requirement Electrical cost Amine inventory makeup Process integration & reliability Skid design vs integrated plant Installed redundancy Project was awarded to PPTech & Cansolv 10 Title of presentation Speaker Place, date [ OPTIONAL ]

11 Detail engineering of Cansolv / PPTech plant Reliability Installed spare magnetically driven (Magdrive) pumps Closed drain and flushing system for amine Flexibility in supply volume - direct usage of supplied gas No liquefaction and limited gas storage in scope Boiler specified at highest possible efficiency and lowest NOx Insert construction photo of CO2 plant Thermal Reclaimer required to manage buildup of impurities in the amine Continuous operation vs Batch distillation 11 Title of presentation Speaker Place, date [ OPTIONAL ]

12 Commissioning / Performance run Plant started up within two weeks of mechanical completion Performance run took place with in a month of start up All performance criteria was met during 72h continuous performance run. Amine usage and reliability needed to be tested over a longer operational period Availability was successfully confirmed during first 6 months of continuous operation Amine usage was higher than anticipated o ongoing work to identify amine losses o understand degradation process and how to optimize it. 12 Title of presentation Speaker Place, date [ OPTIONAL ]

13 Lessons Learnt Stripping energy main cost driver ~(1.2-2) kg steam per kg CO 2 produced depending on the specific technology implemented All possible energy recovery should be implemented, e.g. Recovering flash vapours from the hot lean amine Highest efficiency of Rich / lean amine energy exchanger Stable operation increases opportunity to optimize stripping steam and hence prevent over or under stripping of CO 2 from the amine 13 Title of presentation Speaker Place, date [ OPTIONAL ]

14 Lessons Learnt Integration between supply and usage of CO 2 is critical Natural operating strategy is to generate an over supply of CO 2 gas and vent the excess Amine usage and degradation is a complex process with many parameters influencing the spread of components and their respective concentrations. The Cansolv amine is relatively recent in development and the overall understanding of its degradation is limited Process is sensitive to feed gas composition containing NOx, SO 2, O 2 Some amine compounds are more sensitive to higher temperature operation Impurities in amine can act as catalyst for further degradation 14 Title of presentation Speaker Place, date [ OPTIONAL ]

15 Future Site based Investigations Additional gas storage or liquefaction Lower cost steam supply (Coal instead of Gas) Alternative CO 2 feed steam if load on gas boiler is reduced Improve overall plant energy recovery Integration of Gas fire electrical generation. 15 Title of presentation Speaker Place, date [ OPTIONAL ]