The use of OLI and Aspen Plus to develop / analyse & optimise a strategy for the removal of specific gases from a reformed gas stream

Transcription

1 The use of OLI and Aspen Plus to develop / analyse & optimise a strategy for the removal of specific gases from a reformed gas stream Dr Ralph Grob Sasol Technology October 2007

2 forward-looking statements Sasol has made certain forward-looking statements in this presentation relating to analyses and other information which are based on forecasts of future results and estimates of amounts not yet determinable. These statements may also relate to our future prospects, developments and business strategies. Words such as believe, anticipate, expect, intend, seek, will, plan, could, may, endeavour and project and similar expressions are intended to identify forward-looking statements, but are not the exclusive means of identifying such statements. By their very nature, forward-looking statements involve inherent risks and uncertainties, both general and specific, and there are risks that the predictions, forecasts, projections and other forward-looking statements will not be achieved. If one or more of these risks materialize, or should underlying assumptions prove incorrect, our actual results may differ materially from those anticipated in this presentation. You should understand that a number of important factors could cause actual results to differ materially from the plans, objectives, expectations, estimates and intentions expressed in such forward-looking statements. These factors include among others, and without limitation: the outcomes in developing regulatory matters and the effect of changes in regulation and government policy; the political, social and economic conditions and developments in the world, especially those countries in which we operate; our ability to maintain key customer relations in important markets; our ability to improve results despite unusual levels of competitiveness; the continuation of substantial growth in significant developing markets, such as China; the ability to benefit from our capital spending policies; growth in significant developing areas of our business; changes in the demand for and international prices of crude oil, petroleum and chemical products and changes in currency rates; our success in continuing technological innovation; our ability to maintain sustainable earnings despite fluctuations in foreign exchange rates and interest rates; our ability to attract and retain sufficient skilled employees; and our success at managing the risks of the foregoing. The foregoing list of important factors is not exhaustive; when relying on forward-looking statements to make investment decisions, you should carefully consider the foregoing factors and other uncertainties and events. Such forward-looking statements apply only as of the date on which they are made, and we do not undertake any obligation to update or revise any of them, whether as a result of new information, future events or otherwise. Contact persons: Cavan Hill ( , cavan.hill@sasol.com) Brian MacKinnon ( , brian.mackinnon@sasol.com) Hubert Naude ( , hubert.naude@sasol.com) Additional sources of information on the investor section of Sasol s website IFRS Annual report and Annual report on form 20-F: Sasol reports its results on a biannual basis in IFRS and annually in US GAAP. Sasol s financial year end is June. Analyst fact book: A resource for analysts, shareholders and others seeking detailed financial and operating information about the company. This section includes key extracts from the Annual Report. Investor Insight Newsletter: Published twice a year between financial reporting periods and includes a business review and updates on several key projects and initiatives at Sasol.

3 Topics Sasol & Sasol Technology Problem definition Choosing the right electrolyte package for the job Why use OLI Benefits of using OLI and Process Simulation tools Testing against the real system Documenting the results

4 Topics Sasol & Sasol Technology Problem definition Choosing the right electrolyte package for the job Why use OLI Benefits of using OLI and Process Simulation tools Testing against the real system Documenting the results

5 Sept 2007

6 salient features Sasol was founded in 1950 and listed on the JSE Ltd (JSE) in 1979 and on the New York Stock Exchange (NYSE) in 2003 current market capitalization value around US$23 billion, with current earnings from continuing operations (interim 31 Dec 06) of US$1.1 bn employing people world-wide Sasol is based in South Africa with facilities in 15 countries including the USA, Germany, Italy, the Middle East, West Africa, Malaysia and China Sasol produces ±20% of South Africa s saleable coal and about 37% of the country s current liquid fuel requirements (through Sasol Synfuels syncrude-based fuel component output and Sasol s 64% share in the crude-based Natref output) Sasol supplies all of South Africa s pipeline gas and is the country s only producer of various chemical feedstocks, most notably ethylene, propylene, ammonia, ketones and methanol Sasol is South Africa s largest single industrial investor R30.8 billion expected to be invested locally over the next 3 fiscal years over 50 years of innovation 1950s technology phase first production of fuel from coal 1960s broadening phase crude-oil refining and industrial gas 1970s expansion phase Secunda coal-to-liquids complex established listed on JSE (1979) 1980s consolidation phase 1990s diversification phase growth of domestic chemicals portfolio 2000s globalization phase gas-to-liquids (GTL)

7 Sasol s integrated business model Sasol is an integrated oil & gas company with substantial petrochemical interests. The Fischer-Tropsch process lies at the heart of Sasol, allowing it to convert coal and natural gas into synthetic fuels and chemicals. Sasol is integrated upstream to produce its raw materials, and downstream into fuel and chemical production and marketing. Exploration and Production Syngas Production Fuel products Sasol obtains its raw materials (coal, gas and crude oil) through its coal mining activities and oil and gas exploration and production activities, which are supplemented by purchases from the open market. Some raw materials are sold directly to external markets. Using steam and oxygen at high temperatures, coal is gasified and natural gas reformed to produce synthesis gas [syngas, a mixture of carbon monoxide and hydrogen]. In the liquid fuels business, synthetic fuel components are upgraded, and marketed together with conventional fuels produced in a refinery from crude oil. Co-products Coal gasification and the F-T processes also produce co-products for recovery and beneficiation. These include ammonia, crude-tar acids and sulphur. Fischer-Tropsch Conversion Using a catalyst, the Fischer-Tropsch (F-T) reaction converts syngas into a range of hydrocarbons - co-products, fuel and chemical components. Lowand high-temperature operating modes provide different product splits. Chemical products Chemical intermediates from the F-T process, are separated, purified and, together with conventional chemical raw materials, converted to a range of final products - polymers, solvents, olefins and surfactants, waxes and other products. Markets Sasol markets products directly to the consumer, as well as to commercial and industrial markets, integrating its upstream and downstream activities.

8 Overview Coal / Gas-to-liquids

9 GTL & CTL are based on Fischer Tropsch technology GTL gas natural gas gas reforming oxygen coal Fischer Tropsch process fuels coal coal gasification ammonia, phenolics pitch & tar, sulphur chemicals steam CTL

10 the push for natural gas monetisation vs. coal-based energy opportunities major gas provinces Evaluating opportunities oil exporting regions ORYX GTL in production ORYX expansion evaluation Evaluating opportunities Evaluating opportunities Evaluating opportunities CNL & NNPC 34k bbl/d Nigeria construction in progress important criteria: sufficient quantities of economically priced gas ideally locations with existing infrastructure access to suitable product markets favourable investment climate Evaluating opportunities Evaluating opportunities CTL opportunities under evaluation Gas-rich regions & likely future GTL locations

11 fuel production in South Africa Pande & Temane blocks 16 and 19 capacity Sapref 180,000 b/d Enref 125,000 b/d Calref 100,000 b/d Natref 108,000 b/d PetroSA 45,000 b/d Synfuels 150,000 b/d Mossel Bay Sasolburg Secunda refineries synfuel plants crude oil pipeline refined products pipeline existing gas pipeline natural gas pipeline o prospecting areas

12 Cluster overview

13 main operating divisions energy cluster chemical cluster Mining coal mining activities Polymers production and marketing of ethylene and propylene monomers, polypropylene, polyethylene and PVC South Africa Synfuels Oil production of liquid fuels, gases and chemical products crude oil refining; blending and marketing of fuels and lubricants Solvents Nitro manufactures and markets globally a wide range of oxygenated solvents and co-monomers manufactures and markets ammonia, mining explosives and fertilizers Gas distributes and markets natural and methane-rich gas Wax operates wax manufacturing, blending and marketing operations International Synfuels International Petroleum International develops and implements international ventures based on Sasol s F-T technology develops & manages international upstream interests in oil and gas exploration and production activities Technology other custodian and innovator of group s technology, engineering and project management Financing responsible for centrally managing the group s cash and liquidity and all finance related activities

14 Cluster Sasol Technology

15 Sasol Technology Research, Conceptualise, Design and Execute projects These projects serve the growth aspirations of the Sasol Group world wide Sasol Technology can be classified as a knowledge intensive organisation Total number of permanent employees Engineers (Including 95 young Engineers recent to Sasol Technology) 310 Scientists 225 other professionally qualified personnel 315 administrative/ supporting personnel copyright reserved 2007, Human Resource department, Sasol Technology

16 Problem definition Sasol & Sasol Technology Problem definition Choosing the right electrolyte package for the job Why use OLI Benefits of using OLI and Process Simulation tools Testing against the real system Documenting the results

17 Problem Definition Take the raw gas Coal / Gas to Liquids and remove specific gases Use a column with a stream to remove unwanted gases into the liquid stream and provide a clean gas to the rest of the process Clean gas stream must have impurities at the PPM and PPB levels specified by the process vendors SOLUTION is: Treat the hot gases with a liquid solution rich in electrolytes to remove the gases to the required PPM and PPB levels

18 The study Knowing the feed flows, conditions and component analysis what electrolyte mixture will work in the removal of the unwanted gases: Which electrolyte system to use? What concentrations of electrolyte solutions should be used? How much of the electrolyte solution to use What column configuration to use: Packed vs. Trayed Where to feed the electrolyte solutions 1, 2 or more feeds How many stages Temperature and Pressure of operation conditions

19 Topics Sasol & Sasol Technology Problem definition Choosing the right electrolyte package for the job Why use OLI Benefits of using OLI and Process Simulation tools Testing against the real system Documenting the results

20 Choosing the right Electrolyte data package for the job In the R&D environment there were several known electrolyte packages available: (alphabetical list no preference in the order given below.) Aspen Plus (PITZER and ElecNRTL) JESS MINTEQA2 OLI

21 Standardising on the best From the R&D perspective JESS and MinteqA2 were useful to provide: Theoretical mixtures based on experimental data All sorts of potential / theoretical chemical reactions Data was available from 100 s of different sources From a practical simulation point of view Could not be used directly with a simulation package Data provided would need to be regressed to fit Aspen Plus data models Aspen Plus Couldn t trust the chemical reactions provided Range of ionic species was too few Didn t have some of the solvents we were looking at

22 Topics Sasol & Sasol Technology Problem definition Choosing the right electrolyte package for the job Why use OLI Benefits of using OLI and Process Simulation tools Testing against the real system Documenting the results

23 So why use OLI? Data generated was for known and proven ionic species that we had already measured in the aqueous system Data package could be manipulated to look at different combinations of solutions Data package could be linked with Aspen Plus to generate flowsheet information and create various studies

24 Topics Sasol & Sasol Technology Problem definition Choosing the right electrolyte package for the job Why use OLI Benefits of using OLI and Process Simulation tools Testing against the real system Documenting the results

25 Why combine a process flowsheet and OLI Benefits of putting the model together Known capabilities of the SASOL team (Expertise in Aspen Plus and OLI) What if study capabilities in Aspen Plus Extensive database inside of OLI that was Out of the Box ready for use KEY.. OLI covered all chemical species we were interested in plus some we didn t know would exist Aspen Plus could create multiple flowsheets quickly and effectively

26 The model overview Cleaned gas Electrolyte fluid Alternative 2 nd electrolyte fluid Reform Gas Contaminated liquid to recycle process

27 Modelling effort Modelling effort took 6 months 8 detailed models developed looking at: 5 different types of electrolyte solutions (dosage and chemical species) 6 different gas flowrates 10 different electrolyte solution flowrates Split flowrates for the electrolyte solution Each model measured: ph Composition of key components in the exit gas down to ppb Composition and species of key components in the extraction liquor Composition and flowrate of each of the electrolyte streams Position of the electrolyte streams Plus all the usual flowsheet variables, temp, pres, flowrates etc

28 CO C73 C75 C77 C79 C81 C83 C85 MEOH ETOH PROH BUOH HEXANOL Typical plot of simulation vs actual stream composition NOT THIS PROCESS Stream F2 PROPANE BUTANE PENTANE HEPTANE NONANE UNDC TRDC PNDC HPDC NODC NC21 NC23 C25 C27 C29 C31 C33 C35 C37 C39 C41 C43 C45 C47 C49 C51 C53 C55 C57 C59 C61 C63 C65 C67 C69 C71 A+ simulation Plant METHANE ETHANE N2 WATER

29 Topics Sasol & Sasol Technology Problem definition Choosing the right electrolyte package for the job Why use OLI Benefits of using OLI and Process Simulation tools Testing against the real system Documenting the results

30 Testing against the real system Testing required a skid mounted unit that could connect to various locations within the plant. Skid unit was very well instrumented and linked to a data historian to capture results in real time Results of some of the electrolyte species were difficult to measure on-line so lab samples were taken and analysed off-line

31 Results: Components measured in the OLI/Aspen Plus model were within 2-3 ppm or 5-9 ppb of experimental results Flowrates, Temperature and Pressure of the feeds in the OLI/Aspen Plus model were set to be the same as that measured in the plants Flowrates, Temperature and Pressure of the products in the OLI/Aspen Plus model were within 1 4% of those measured in the plants and well within the accuracy of the meters used to measure these variables

32 Results Actual results cannot be shown for commercial reasons. They were however good enough for the simulation to be used to develop a process

33 Topics Sasol & Sasol Technology Problem definition Choosing the right electrolyte package for the job Why use OLI Benefits of using OLI and Process Simulation tools Testing against the real system Documenting the results

34 Documenting the results Standard templates are used within Sasol that act as an Aide Memoir for the developer of the applications Documentation regarded as important lesson in communicating the results to other team members

35 Well documented models

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