LURGI S HP-POX DEMONSTRATION UNIT A MILESTONE TO IMPROVED SYNGAS PRODUCTION Gasification Technologies 2004 Washington, DC, October 3 6, 2004 Ulrich Wolf, Holger Schlichting - Lurgi Oel Gas Chemie GmbH, Germany INTRODUCTION The importance of syngas as intermediate product on the gas to chemicals route and for power generation with carbon dioxide separation for sequestration calls for new, innovative processes. Lurgi took up this challenge to fundamentally improve syngas production technology and decided to build a multi process demonstration unit for syngas production technologies. This project is jointly pursued together with the University of Freiberg and financially supported by the German Ministry of Economics and Technology (BMWi) and by the Saxon Ministry of State for Science and Art (SMWK). This year the demonstration unit was successfully commissioned and the research program started with tests of autothermal reforming of natural gas. The main driving force for the project is the increasing demand for economic solutions for the oil and gas industry with regard to natural gas usage. Availability of natural gas resources is predicted to last for more than 130 years, which is 2 to 3 times longer than the availability of oil resources. The main natural gas resources are located in remote areas. Due to the difficult and expensive transport of gas, a considerable amount of gas is currently just flared wasting energy and money and polluting the environment. Conversion of natural gas to transportable liquid fuels and valuable chemicals is essential for economical natural gas usage. Syngas is the main intermediate on the route from natural gas to a wide range of products. Lurgi has a long tradition in providing technologies for syngas production from all kind of feedstock such as coal, liquid hydrocarbons and gas and also in the downstream technologies for conversion of syngas to valuable products such as methanol, ammonia and Fischer-Tropsch products. Continuous intensive development improved the technology allowing for larger single train capacities resulting in lower investment costs and reduced operating costs. The resulting lower syngas price opens the path for new products based on natural gas. Consequently Lurgi developed new processes based on natural gas feedstock such as the production of Propylen, DME, synthetic fuels and power. SYNGAS CONVERSION ROUTES The first step of natural gas usage is the conversion of the feed gas to synthesis gas. Various processing routes exist for this syngas. Some groups favor the processing via Fischer Tropsch synthesis to transport fuels. Lurgi's evaluations show advantages in efficiency and economics via the intermediate production of methanol. Methanol is easily processed further to chemicals such as MTBE or acetic acid. Transport fuels of highest quality are produced via the MT-Synfuel process. Lurgi Oel Gas Chemie GmbH\32SCHL copy.doc Page 1 of 7
Fuel Gas Natural Gas / Associated Gas MegaSyn Fischer Tropsch Synthesis Megammonia Mega- Methanol Upgrading MTC MtSynfuels MTP MTO Acrylic Acid LPG Naphtha Diesel Waxes Ammonia Fuel Cells Chemicals (MTBE, Acetic Acid, Formaldehyde,...) Diesel, transport. fuels Propylene/Polypropylene Acrylic Acid/Acrylates Ethylene/Propylene Lurgi proprietary process MtPower MTH Power/Fuel/DME(Diesel) Hydrogen Fig. 1 Gas Processing Routes Lurgi has succesfully developed the MTP process (Methanol To Propylene), a selective conversion of methanol to propylene. This opens the path to polymer production from natural gas, which is currently based completely on oil. Lurgi has operated a MTP pilot plant for more than 2 years in a side stream of the Statoil methanol plant in Norway. Methanol can directly be burned in gas turbines for power production, which has been demonstrated and is offered for example by GE. It can also be converted to DME dimethylether. DME is a perfect fuel for gas turbines and can serve as alternative to diesel fuel. Methanol can also be used as hydrogen carrier. Conversion of methanol to hydrogen is an alternative to naphtha reforming. Lurgi has developed a new scheme for ammonia production based on the MegaSyn technology. The Megammonia process allows the efficient production of more than 4000 tpd of ammonia in a single train. Investment cost will be more than 25% lower compared to the currently available technology of 2 trains with 2000 tpd each and 20% lower compared to single train 4000 tpd plant based on current technology respectively. Operating costs decrease by 10-15% than the currently operating plants. Lurgi offers the full process chain from natural gas cleaning to the end products. DEVELOPMENT IN SYNGAS PRODUCTION Figure 2 is an example of the status of syngas production 12 years ago. The photo shows the syngas production units of the Gas to Liquids plant of PetroSA in Mosselbay, South Africa. The plant comprises 3 combined reforming syngas production trains, a Synthol Fisher Tropsch synthesis and a Lurgi COD plant, which converts light olefins to diesel. Each syngas production train consists of a steam reformer and an autothermal reformer. Each train produces 300,000 Nm 3 /h syngas, so in total 900,000 Nm 3 /h, which is converted to 350,000 tpa of diesel fuel and 100,000 tpa gasoline. Lurgi Oel Gas Chemie GmbH\32SCHL copy.doc Page 2 of 7
Fig. 2: Status of syngas production 1992 GTL-plant PetroSA Location: Technology: Capacity: Republic Of South Africa Combined Reforming, Synthol Fischer-Tropsch Synthesis, COD (Conversion of Olefins to Distillates) Syngas: 900,000 m 3 N/h (806 MMSCF/d) in three trains Products: 250,000 tpa diesel fuels, 100,000 tpa gasoline Today Lurgi build the same syngas capacity in one single train in the MegaSyn process. Only one steam reformer is installed with a similar size as those in figure 2, and only one autothermal reformer is required. The investment costs are reduced significantly due to the single train concept and the small size of the expensive steam reformer. An example of the present status is shown in figure 3. The MegaMethanol Plant Atlas in Trinidad produces 5000 tpd of methanol. The plant is built in one single train generating 530,000 Nm 3 /h of syngas for the MegaMethanol synthesis loop. The plot area is 600 m by 400 m. Large tank capacities are required, since most of the methanol produced will be shipped to the customers around the world. Commercial production of methanol started in June 2004. Lurgi Oel Gas Chemie GmbH\32SCHL copy.doc Page 3 of 7
Fig. 3: Present Status of Syngas production - MegaMethanol Plant Atlas Location: Technology: Capacity: Trinidad MegaSyn Combined Reforming / MegaMethanol Methanol Synthesis Syngas: 530,000 m 3 N/h (475 MMSCF/d) Products: 5,000 tpd methanol THE HP-POX DEMONSTRATION UNIT PROJECT Lurgi is pursuing a research project jointly with the Institute of Energy Process Technology and Chemical Engineering of the Technical University and Mining Academy of Freiberg. The project, scheduled to last four and a half years, is backed by the German Ministry of Economics and Technology (BMWi) and by the Saxon Ministry of State for Science and Art (SMWK). A demonstration unit is build at the University of Freiberg to perform tests for various syngas production processes. The results from the demonstration unit will be the basis for fundamental improvements of existing Lurgi processes for converting liquid and gaseous feedstocks to synthesis gas. One target is the design of larger single train capacities. This can be achieved by increasing operating pressure to increase capacity without increasing equipment sizes. This is an important factor to facilitate bancability. New projects are today financed, in large measure, by bank loans. Bankability becomes a big issue which describes confidence of the investors in the technology. Confidence increases with the portion of proven process steps, the length of the reference list and small scale up factors for new equipment and process steps. In the MegaSyn plants equipment size is close to commercially available limits at the current operating pressure. Bulk material such as piping and valves reach the upper end of international standards. Larger equipment sizes would result in expensive developments of the equipment suppliers and larger size of bulk material would increase investment costs significantly. The overall plant efficiency is improved by higher pressure of the syngas. The compression energy for the downstream synthesis reduces significantly. Higher operating pressure results in larger potential single train capacities at constant equipment size which will reduce specific capital and operating costs significantly. As an additional benefit the improved processes will save resources by improving efficiency. Also, environmental pollution related to energy production will be reduced significantly. The optimization of the syngas production Lurgi Oel Gas Chemie GmbH\32SCHL copy.doc Page 4 of 7
processes will reduce the price of syngas. This will open the path for new developments in the entire technology chain, new products based on natural gas will become competitive. Fig. 4 : View of HP-Pox Demonstration Unit PLANT DESCRIPTION The plant is designed as multi process test facility for catalytic autothermal reforming and non catalytic partial oxidation of natural gas as well as gasification of liquid hydrocarbon streams, heavy oil and residues. The maximum operating pressure is 100 bar and the throughput is 500 m3/h for natural gas feedstock and 500 kg/h for liquid feedstock, respectively. The plant comprises two feed systems - one for natural gas and one for liquid streams. Natural gas from the pipeline is compressed and preheated to the desired temperature. Liquid feedstock is stored in a thermostatic tank and fed via high pressure pump and a preheater into the reactor. Liquid oxygen is supplied from a storage vessel, pumped to operating pressure, evaporated and preheated. Process steam is produced in a separate high pressure steam boiler. The reactor is refractory lined with a top mounted burner. At the bottom the hot gas is routed directly to a water quench to shock cool the gas and avoid all back reactions during gas cooling. In a later stage a waste heat boiler shall be added to the plant. The reactor is equipped with nozzles at various elevations which enable the installation of measuring devices such as temperature sensors, optical sensors or may be used as sample points. A catalyst bed is installed in the reactor for operation as autothermal reformer of natural gas. This allows tests of catalyst performance such as high temperature aging of catalyst and soot formation under low steam to carbon operation. The catalyst is removed for operation as non-catalytic gas pox or partial oxidation of liquid streams (MPG = Multi Purpose Gasification). Lurgi Oel Gas Chemie GmbH\32SCHL copy.doc Page 5 of 7
Fresh water Water Treatment Steam Generator Flue Gas Liquid Feeds Storage Natural Gas Liquid O 2 Compressor Pump and Vaporizier Desulphurisation Reactor Flare System Soot Water Cooler Soot Water Nitrogen Supply Instument Air Supply Measuring Station Power Supply Analytical Area Fig. 5: Block flow diagram of HP-POX-demonstration unit Individual burners have been designed for the various processes and operating pressures. The burner for autothermal reforming distinguishes from the gas pox burner because of different steam to natural gas ratios and the related specific oxygen consumption. Various operating pressures ask for individual burner geometry in order to keep the velocity of the feed streams in the desired range. The product gas leaving the quench is further cooled expanded and routed to a combustion chamber and flared. If the feedstock contains sulfur, the raw gas is desulfurized. The process water and the water used for gas scrubbing is collected and transported to a suitable waste water treatment plant. All utilities are produced on site. An electrical heated boiler produces the required superheated process steam. Nitrogen for flushing the system and safety is supplied from nitrogen-bottles. The plant is controlled via a DCS system which is installed together with the interlock safety system in the control room container. In addition to the online analytical instruments special analysis will be performed by the analytical laboratories of the university. RESEARCH PROGRAM A research program was defined which serves both the need of the scientific improvement of models to describe the reactions and to improve the engineering database. Important objectives are the influence of pressure and temperature on the syngas composition and trace components. The research program started with tests for catalytic autothermal reforming of natural gas. The main parameters that determine gas composition have been varied such as pressure, oxygen to feed ratio, steam to feed ratio and residence time. Lurgi Oel Gas Chemie GmbH\32SCHL copy.doc Page 6 of 7
Low steam to feed ratios are important for generating CO rich syngas. Undesired soot production at low steam to feed ratio has to be avoided to prevent catalyst blockage. Tests in this operating range are planned to better understand and to further improve the models of soot formation. Operation in the gas-pox mode is next on the test run agenda. Non-catalytic partial oxidation at a pressure up to 100 bar shall be tested. The operation parameters to be varied are basically identical to those for autothermal reforming. Finally the plant will be operated with liquid feedstock such as heavy residue oil again with a pressure up to 100 bar. Fig. 6: Reactor building of HP-POX-Demonstration unit REFERENCES H. Koempel, W. Liebner, Gas to Liquids? Gas To Chemicals? Gas to Value!, ERTC Petrochemical Conference, Amsterdam, February 20-22, 2002 M. Rothaemel and H-D. Holtmann, MTP, Methanol To Propylene - Lurgi s Way, DGMK-Conference Creating Value from Light Olefins Production and Conversion, Hamburg, October 10 12, 2001 S. Streb and H. Göhna: MegaMethanol - paving the way for new down-stream industries, World Methanol Conference, Copenhagen (Denmark), November 8 10, 2000 W. Davey, T. Wurzel, E. Filippi: Meagammonia - Mega Ammonia Process for the New Century, Nitrogen 2003, Warsaw (Poland), February 23-26, 2003 Presenter/Contact: Ulrich Wolf Dr.-Ing. H. Schlichting Director Syngas Technology Process Manager Tel 49 69 5808 3238 Tel 49 69 5808 1418 Fax 49 69 5808 2645 Fax 49 69 5808 2645 Email ulrich_wolf@lurgi.de Email dr_holger_schlichting@lurgi.de Lurgi AG Lurgiallee 5 60295 Frankfurt/Main, Germany Lurgi Oel Gas Chemie GmbH\32SCHL copy.doc Page 7 of 7