lurgi gas to chemical.pdf

© Gastech 2005

Lurgi’s Gas To Chemicals (GTC®): Advanced technologies for natural gas monetisation

Harald Koempel, Waldemar Liebner, Matthias Wagner Lurgi AG

Lurgiallee 5, D-60295 Frankfurt am Main, Germany

Gastech 2005, Bilbao, Spain, 14 –17. March 2005 Session 5: Gas-to-Liquids, Methanol, DME, CNG & Alternatives”

© Gastech 2005 Liebner 2

Natural Gas in the 21st Century: A Key Feedstock for (Petro-) Chemicals

The total proven gas reserves amount to approx. 180 trillion cubic meters world-wide which translates into a gas reserve-to-production ratio, i.e. a gas reserve lifetime of 70 years. Furthermore, estimated additional gas reserves will cover a lifetime of 65 years more. [Cedigaz 2003] Compared with the reserve lifetime of 41 years for petroleum and 230 years for coal, there is no doubt that natural gas will be a key fuel component in the 21st century.

However, a considerable portion of this reserve is wasted yearly: More than 80 billion cubic metres of natural gas

and oil associated gas are flared for technical reasons or for lack of markets. This explains the main incentive for engi-neers and environmentalists as well to come up with novel ideas for the utilisation of this gas.

Existing technologies for natural gas conversion are based the conversion to synthesis gas (or short: “syngas”, a

mixture of carbon monoxide, CO, and hydrogen, H2) and from there to hydrogen and ammonia, Fischer-Tropsch products as well as methanol and DME. Currently, the production of chemicals requires only around 5% of world gas consumption [Quigley and Fleisch 2000].

Figure 1 in a nutshell summarizes additional new routes and technologies: The very first step is again the conver-

sion to synthesis gas, only this time in a highly efficient single-train process for truly large capacities, namely MegaSyn® which is described briefly as “optimised reforming” in the methanol chapter. [Streb and Göhna 2000] As before, hydro-gen, ammonia and Fischer-Tropsch products can be derived from this syngas, only now at lower costs. This cost advan-tage is carried over to MegaMethanol® and even boosted there by way of integration.

Since Lurgi introduced its new groundbreaking MegaMethanol® process for plants with a production of 5,000 tons

of methanol per day and more, methanol will be available at a constant low price in the foreseeable future. This devel-opment has an enormous impact on downstream technologies for the conversion of methanol to more valuable products.

The first derivative of methanol in this context is DME which has a high potential as alternative to conventional

diesel fuel, as feed gas for gas turbines in power generation and as supplement to LPG. Therefore DME is found in the MtPower route as energy carrier. As a chemical it would appear under MTC, methanol to chemicals.

The next step is the use of methanol as feedstock for the production of olefins which is one of the most promis-

ing new applications. Lurgi’s new Methanol-to-Propylene (MTP®) process presents a simple, cost-effective and highly se-lective technology. This route allows for the production of polypropylene and of petrochemicals which then would be gas-based. The last route to be discussed here in detail is MtSynfuels®

, a methanol-based technology for the production of synthetic transportation fuels which compares well with the FT-processes. Lurgi MegaMethanol®: Basis for More Valuable Products

The term MegaMethanol® refers to plants with a capacity of more than one million metric tons per year, the ac-tual “standard” size being 1.7*106 t/a (equivalent to 5,000 t/d). To achieve such a large capacity in a single-train plant a special process design is required. For this reason Lurgi focused on the most efficient integration of syngas generation and methanol synthesis into the most economical and reliable technology for the new generation of future methanol plants [Streb and Göhna 2000].

Figure 1. Gas to Chemicals Processing Routes

MegaSyn®

Fischer Tropsch

Synthesis

Mega-Methanol®

Upgrading

MTO

MtPower

MTH

MtSynfuels®

Acrylic Acid

Fuel GasLPGNaphthaDieselWaxesAmmoniaFuel CellsChemicals (MTBE, Acetic Acid, Formaldehyde, ...)Diesel, transport. fuelsPropylene/PolypropyleneAcrylic Acid/AcrylatesEthylene/PropylenePower/Fuel/DME(Diesel)Hydrogen

MTP®

Natural Gas /Associated Gas

MTC

Megammonia®

Figure 1. Gas to Chemicals Processing Routes

MegaSyn®

Fischer Tropsch

Synthesis

Mega-Methanol®

Upgrading

MTO

MtPower

MTH

MtSynfuels®

Acrylic Acid

Fuel GasLPGNaphthaDieselWaxesAmmoniaFuel CellsChemicals (MTBE, Acetic Acid, Formaldehyde, ...)Diesel, transport. fuelsPropylene/PolypropyleneAcrylic Acid/AcrylatesEthylene/PropylenePower/Fuel/DME(Diesel)Hydrogen

MTP®

Natural Gas /Associated Gas

MTC

Megammonia®


The unique ad-vantages of the Lurgi MegaMethanol® technol-ogy result in “ex-gate” methanol prices of about 65 $/t or less and make this process ideally suited as part of Lurgi’s route from C1 to propyl-ene and others. In summer 2004 the first such plant of 5,000 t/d capacity started up suc-cessfully: Atlas/Trinidad is running at above de-sign capacity ever since. The second one, Za-gros/Iran, is starting up these days (spring 2005). Three more have been ordered in 2004, with capacities of 5000, 6750 and 5400 t/d respectively. Conceptual studies and engineering activi-ties for MegaMethanol® plants with single-train capacities of up to 7,500 t/d and more have been successfully finalised making these plant sizes ready for commercialisation.

An environmental side note: the 80 billion cubic meters of natural gas flared or vented annually as mentioned above would be sufficient to feed about 60 MegaMethanol® plants with a capacity of 102 million tons per year in total.

DME - A Valuable Product From Methanol

Dimethyl Ether, DME, is industrially important as the starting material in the production of the methylating agent dimethyl sulphate and is used increasingly as an aerosol propellant. In the future DME can be an alternative to conven-tional diesel fuel or a feed gas for power generation in gas turbines. Both applications are based on large-scale produc-tion facilities in order to achieve an economic fuel price. According to the audiences’ consensus during the First Interna-tional DME Conference “DME 1”, in October 2004 in Paris, DME is on the verge of breakthrough into the energy and transportation fuel sectors. [Boll, Liebner 2004]

Traditionally, DME was obtained as by-product of the high-pressure methanol synthesis. Since the low-pressure methanol synthesis was established, DME has been prepared from methanol by dehydration in the presence of suitable catalysts. The dehydration is carried out in a fixed-bed reactor. The product is cooled and distilled to yield pure DME. A modification of the methanol synthesis would allow for co-generation of DME within the methanol synthesis loop. This technical path comprises two disadvantages. While dehydrating methanol, the water vapour content increases, thus enhancing the water gas shift reaction. By converting CO into CO2, the quality of the synthesis gas deteriorates. The kinetics of the reaction of CO2 and H2 is slower than the one of CO and H2. As a result, the synthesis catalyst volume and the recycle loop capacity have to be increased. In addition, due to its low boiling point a cryogenic separation is required in order to separate DME from the synthesis recycle loop.

As a result of these disadvantages of the co-generation of methanol and DME Lurgi favours the concept of gen-erating DME from methanol by dehydration. This was discussed and demonstrated in the DME1 conference mentioned above. If a DME Unit is added to the MegaMethanol® plant, the distillation of methanol is reduced from a three-tower system to one tower at considerable savings. Figure 3 shows the simple and inexpensive flowsheet for the dehydration of methanol. In this process all types and qualities of DME can be produced. The different specifications for fuel gas, power generation or pure DME can be achieved just by varying size and design of the DME distillation towers.

The economics of the Lurgi DME Process are summarised in Table 1 assuming the following general set-up: Natural gas consumption and Product Value (EPC) are standardised on metha-nol equivalent (7050 t/d methanol capacity); DME product quality is at least 99.2 wt% DME; Natural gas consumption figures include energy demand for air separation and power generation; Total Fixed Cost include air separation, power genera-tion and off-sites; Natural gas price assumed as US$ 0.5 / MMBtu; Depreciation is 10 % of Total Fixed Cost; Return on Investment (ROI) is set to

Figure 2. Simplified Diagram of Lurgi‘s MegaMethanol® Technology

Desulphur-ization

Pre-Reforming

AutothermalReforming

MethanolDistillation

Air-Separation

PureMethanol

Oxygen

NaturalGas

PSA

MethanolSynthesis

Air

• Optimised reforming: high flexibility in stoichiometric number

• high energy efficiency for MeOH synthesis

• low investment costs• large single-train capacity

methanol productioncost: 65 $/t

Syngas

Purge Gas

Crude Methanol

Steam

BoilerFeedWater

Gas-CooledReactor

Water-CooledReactor

Figure 3. DME Production by Methanol Dehydration

DMEReaction

DMEDistillation

DMEProductMethanol

H2ORecycle

MeOHRecycle

WasteWater

Off-gas

SyngasProduction

DMEReaction

DMEDistillation

DMEProductMethanol

H2ORecycle

MeOHRecycle

WasteWater

Off-gas

SyngasProduction


20 % of Total Fixed Cost; Operating cost for operator staff, plant overhead, maintenance labour and material are in-cluded.

All investment cost figures are budgetary estimates of +/- 20 % accuracy. (See also “disclaimer” at the end of the paper.) Specific site conditions are not reflected with these numbers. The figures show the superb economics of MegaMethanol® in combination with a separate dehydration step.

Table 1: Economics of the Lurgi MegaDME Process

Plant Type Mega Methanol & Dehydration

DME capacity 5,000 t/d

Natural Gas Demand 28.5 MMBtu / t MeOH 40.2 MMBtu / t DME

Total Fixed Cost (EPC) 415 MM US$ (€)

Cost of production 93 US$ (€) / t DME

From all this it follows that DME, a traditional derivative of methanol, can be a promising alternative fuel for

power generation, diesel, LPG or the manufacture of olefins when produced in large capacities. The production of DME by dehydration of methanol, i.e. in two steps, is more economic than a single-step synthesis as proposed elsewhere. This was discussed in detail in a paper for AIChE [Rothaemel, Liebner 2004].

Propylene - An attractive product with high value

Demand growth of propylene is projected at higher than 5% worldwide with marked regional spikes as e.g. for Iran, India, PR China. Polypropylene is by far the largest and fastest growing of the propylene derivatives, and requires the major fraction of about 60 % of the total propylene. The increasing substitution of other basic materials such as pa-per, steel and wood by PP will induce a further growth in the demand for PP and hence propylene. Other important pro-pylene derivatives are acrylonitrile, oxo-alcohols, propylene oxide and cumene. The average growth rate for propylene itself is estimated very conservatively to be 4.5 % per year for the next two decades. How to satisfy this demand for propylene?

Currently, steam crackers and FCC units supply 66 % and 32 %, respectively of propylene fed to petrochemical processes. However, as FCC units primarily produce motor gasoline, and steam crackers mainly ethylene, propylene will always remain a by-product (e.g. 0.04-0.06 t/t of ethylene for steam crackers with ethane feedstock and 0.03-0.06 t/t, respectively of motor gasoline and distillates production for FCC units). Current forecasts indicate an increasing gap of propylene production that has to be filled by other sources. Lurgi’s new MTP process directly aims to fill that gap.

Lurgi’s Methanol to Propylene (MTP®) Technology

Lurgi’s new MTP® process is based on an efficient combination of the most suitable reactor system and a very se-lective and stable zeolite-based catalyst. Since the process has been described in detail elsewhere [Rothaemel and Holtmann, 2001], suffice it to say here that Lurgi has selected a fixed-bed reactor system because of its many advan-tages over a fluidised-bed. The main points are the ease of scale-up of the fixed-bed reactor and the significantly lower investment cost.

Furthermore, Süd-Chemie AG manufactures a very selective fixed-bed catalyst commercially which provides maximum propylene selectivity, has a low coking tendency, a very low propane yield and also limited by-product forma-tion. This in turn leads to a simplified purifica-tion scheme that re-quires only a reduced cold box system as compared to on-spec ethylene/propylene separation. With Figure 4 a brief process de-scription reads: Methanol feed from the MegaMethanol® plant is sent to an

Figure 4. MTP: Simplified Process Flow Diagram

Gasoline 143,000 t/a

Fuel Gas 15,000 t/ainternal use

Process Water 936,000 t/afor internal use and/or irrigation

DMEPre-Reactor

ProductConditioning

Propylene519,000 t/a

LPG54,000 t/a

Water Recycle

Olefin Recycle

Methanol, Grade AA1.667 x 106 t/a = 5000 t/d

Product Fractionation

MTP Reactors(2 operating + 1 reg.)

Figure 4. MTP: Simplified Process Flow Diagram

Gasoline 143,000 t/a

Fuel Gas 15,000 t/ainternal use

Process Water 936,000 t/afor internal use and/or irrigation

DMEPre-Reactor

ProductConditioning

Propylene519,000 t/a

LPG54,000 t/a

Water Recycle

Olefin Recycle

Methanol, Grade AA1.667 x 106 t/a = 5000 t/d

Product Fractionation

MTP Reactors(2 operating + 1 reg.)


adiabatic DME pre-reactor where methanol is converted to DME and water. The high-activity, high-selectivity catalyst used nearly achieves thermodynamic equilibrium. The methanol/water/DME stream is routed to the MTP® reactor to-gether with steam and recycled olefins. Methanol/DME are converted by more than 99%, with propylene as the predomi-nant hydrocarbon product. Process conditions in the five or six catalyst beds per reactor are chosen to guarantee similar reaction conditions and maximum overall propylene yield. Conditions are controlled by feeding small streams of fresh feed between the beds. Two reactors are operating in parallel while the third one is in regeneration or stand-by mode. Regeneration is necessary after about 500-600 hours of cycle time when the active catalyst centres become blocked by coke formed in side-reactions. By using diluted air, the regeneration is performed at mildest possible conditions, nearly at operating tempera-ture, thus avoiding thermal stress on the catalyst.

The product gas is compressed and traces of water, CO2 and DME are removed by standard techniques. The cleaned gas is then further processed yielding chemical-grade propylene with a typical purity of more then 97%. Several olefin-containing streams are sent back to the main synthesis loop as an additional propylene source. To avoid accumula-tion of inert materials in the loop, a small purge is required for light-ends and the C4/C5 cut. Gasoline is produced as a by-product.

Water is recycled to steam generation for the process; the excess water resulting from the methanol conversion is purged. This process water can be used for irrigation after appropriate and inexpensive treatment. It even can be processed to potable water where needed.

An overall mass balance is included in Figure 4 based on a combined MegaMethanol® / MTP® plant. For a feed rate of 5,000 tons of methanol per day (1.667 million tons annually), approx. 519,000 tons of propylene are produced per year. By-products include fuel gas (used internally) and LPG as well as liquid gasoline and process water.

Further integration and optimisation of the total plant complex including syngas, methanol, propylene production and offsite facilities will again decrease the capital investment and production costs.

The technological status of MTP® in the areas of process and catalyst can be summarised as follows: The basic process design data were derived from more than 9,000 operating hours of a pilot plant at Lurgi’s Research and Devel-opment Centre. Besides the optimisation of reaction conditions also several simulated recycles have been analysed. Paral-lel to that Lurgi decided to build a larger-scale demonstration unit to test the new process in the framework of a world-scale methanol plant with continuous 24/7 operation using real methanol feedstock. After a cooperation agreement with Statoil ASA was signed in January 2001 the Demo Unit was assembled in Germany and then transported to the Statoil methanol plant at Tjeldbergodden (Norway) in November 2001. Later in 2002 Borealis joined the cooperation.

The Demo Unit was started up in January 2002, and the plant has been operated almost continuously since then. As of September 8th 2003, the Demo Unit completed the scheduled 8000 hours life-cycle test. With that the main purpose of the test was achieved: to demonstrate that the catalyst lifetime meets the commercial target of 8000 hours on stream. Cycle lengths between regenerations have been longer than expected. Deactivation rates of the methanol conversion re-action decreased with operation time. Propylene selectivity and yields were in the expected range for this unit with only a partial recycle. Also, the high quality of the by-product gasoline and the polymerisation grade quality of the propylene were proven. For details see an AIChE paper on the Demo Unit results [Rothaemel, Liebner 2004].

The catalyst development is completed and the supplier commercially manufactures the catalyst. Today, Lurgi is offering the process on fully commercial terms. A contract has been signed on the very first plant

with a capacity of 100,000 t/a of propylene in the Middle East. Basic engineering work has commenced.

From the same region a private investor has signed an LOI on a full-size MTP plant of about 500,000 t/a capac-ity. He has ordered as a first step a pre-basic/cost evaluation the work on which has begun also.

Another LOI is with a state/private investor group in the Caribbean for a capacity of 256,000 t/a where Lurgi has done extensive studies and is now supporting the financ-ing efforts.

GTP Economics

Since propylene by itself is more an intermediate than an end product, an economics estimate was per-formed for a complete natural gas to polypropylene com-plex. In this case of integrating a MegaMethanol® and a MTP® plant we designate the resulting unit as “Gas to Propylene”, GTP®, as shown in Figure 5.

Thus, the economic assessment included the GTP route with a polypropylene unit for the production of a more saleable, higher-value end product. The cases pre-sented here take into account a “difficult” region of re-

Figure 5 Block Flow Diagram - PP Complex

Natural Gas

3.8 M io Nm³/d

Poly- propylene

Plant

GTP Plant

0.52 M t/a Propylene

0.52 M t/a Polypropylene

0.14 M t/a Gasoline

0.9 M t/a Water


mote/stranded gas as well as contingencies for the newly developed route. With that, the investment cost estimate is fairly high and still an attractive return can be expected as seen in Table 4. For the US$ versus € “problem” please refer to “disclaimer” at the end of the paper.

Table 2 shows as Case A the production costs of intermediates and end product derived for the flow sheet of Figure 5. The corresponding rates of return are given in Table 4.

Table 2 Production Cost, GTP/ PP Complex

CASE A: high propylene / low gasoline production

Table 2 GTP PP Capacity t/a 520,000 520,000 Investment Cost EPC Mio $(€) 565 165 Owner’s Cost incl. Capit. Interest Mio $(€) 113 33 Feed Cost US$(€) Natural Gas

0.5$/MMBtu Propylene

$(€)/t Production Cost $(€)/t 210.1 261 - Raw Materials $(€)/t 57.1 212.8 - Utilities $(€)/t 10.8 6.8 - Operation & Maintenance $(€)/t 29.6 8.6 - Plant OVHD & Insurance $(€)/t 31.6 9.2 - Depreciation $(€)/t 81.0 23.6 Credit for by-product Gasoline $(€)/t -35.7 - Cost of Product at ROI = 0 $(€)/t 174 261

Table 3 Production Cost, GTP/ PP Complex

CASE B: low propylene / high gasoline production

Table 3 GTP PP Capacity t/a 440,000 440,000 Investment Cost EPC Mio $(€) 565 165 Owner’s Cost incl. Capit. Interest Mio $(€) 113 33 Feed Cost US$(€) Natural Gas

0. $/MMBtu Propylene

$(€)/t Production Cost $(€)/t 248.6 271 - Raw Materials $(€)/t 67.6 215.2 - Utilities $(€)/t 12.7 6.7 - Operation & Maintenance $(€)/t 35.1 10.2 - Plant OVHD & Insurance $(€)/t 37.4 10.9 - Depreciation $(€)/t 95.8 28 Credit for by-product Gasoline $(€)/t -71.9 - Cost of Product at ROI = 0 $(€)/t 177 271

The remarkable facts here are the low production costs for propylene and for the end product polypropylene. These

leave room for healthy profit margins why this route is seen as the most promising and most economic natural gas utili-sation of those presented here.

Case B as given in Table 3 shows the potential of the same complex to produce a significantly higher amount of gasoline, albeit at the corresponding lower propylene production rate. This was studied as part of a sensitivity and risk analysis. Even in this case far from the original design which is optimised for propylene yield, the rates of return as shown in Table 4 remain impressive.


It should be noted that a very low gasoline price of 130 US$/t has been considered in both cases. According to

the high quality found by the Statoil refinery lab, higher prices would be justified. With these, the profitability of Case B would increase to nearly this of Case A. This robustness is based on the fact that with diminishing selectivity towards propylene automatically the gasoline yield rises and that never any detrimental by-products are formed. Additionally, all “unconverted” compounds are recycled as designed for anyway. In other words, the optimum propylene to gasoline ratio will depend on the relative value of the two products. The main product price -polypropylene’s- was taken as 650 US$/t, a value slightly below the average since 1990 as quoted by CMAI; recent prices as quoted by ICIS-LOR being well in the 900dreds. With these moderate to low product prices and a reasonable investment cost contingency the economic evaluation presented here is purposefully conservative.

Table 4: ROI and IRR, GTP / PP Complex, CASE A, B Table 4 CASE A: high propylene B: high gasoline Investment Cost EPC Mio $(€) 730 730 Owner’s Cost incl. Capitalised Interest Mio $(€) 146 146 Feedstock Cost US$(€) Natural Gas 0.5 $/MMBtu Production Cost Mio $(€) 154.3 150.7 - Raw Materials Mio $(€) 49.7 46.6 - Utilities Mio $(€) 9.1 8.6 - Operation & Maintenance Mio $(€) 19.9 19.9 - Plant OVHD & Insurance Mio $(€) 21.2 21.2 - Depreciation Mio $(€) 54.4 54.4 Revenues Mio $(€) 356.6 317.2 - Gasoline (130 US$/t) Mio $(€) 18.6 31.6 - Polypropylene (650 US$/t) Mio $(€) 338 285.6 Return On Investment 1) ROI % 23.1 19 Internal Rate of Return 2) before tax IRR % 25.1 20.6 IRR on equity (30% of EPC + owner’s cost)

IRRE% 36.8 30.3

1) ROI estimate based on ChemSystems methodology, 2) IRR estimate based on COMFAR

Lurgi’s Fischer-Tropsch Experience

Historically, Lurgi was one of the developers of FT in the 1920-30ties. FT in the form of (fixed bed) ARGE-synthesis was commercialised in 1952 in Sasolburg, RSA. All five original reactors are still in operation. A sixth one was started in 1987 as capacity extension.

Modern FT reactor technology prefers slurry phase reactors, either tubular or fluidised bed. Lurgi has commercial experience in all these reactor designs. Also, Lurgi has designed all syngas production units of all currently operating in-dustrial FT-plants: Sasol/Secunda, RSA, utilising coal gasification; Mossgas, RSA, - combined reforming of NG and SMDS Bintulu, Malaysia - partial oxidation of NG.

The syngas production route which among others is used for MegaMethanol® is offered by Lurgi as MegaSyn® and is available for FT syntheses also.

Lurgi’s Route to Transportation Fuels: MtSynfuels®

Given the economically highly attractive technologies of MegaMethanol® and MTP® as described above it nearly follows by itself to combine them with an industrially proven process for the conversion of olefins to diesel. A gas-based synfuels plant using this process, then named COD (derived from Conversion of low molecular weight Olefins to Diesel), was developed and built by Lurgi for Mossgas (today: PetroSA), RSA, in 1992 and is performing well since its start-up in 1993.

Remarkably, the industrial design was based on a scale-up factor of 3600 over the preceding demonstration

plant. This basically was possible through the use of fixed-bed catalysis (on zeolite basis) which lends itself to easy scale-up. Other important process features are semi-continuous operation and a 98% conversion of C3- and C4- olefins.


The Lurgi route to synfuels, MtSynfuels® shown in Figure 6 is a combination of this type of process with MegaMethanol® and a simplified MTP®. Extensive engineering and estimating stud-ies have been performed to prove the feasibility and economic viability of this new route. Table 5 shows the technical results, the product slate and Table 6 gives the economics as a comparison with an existing FT plant.

In an earlier study the authors [Koempel, Liebner, Feb. 2002] have summarised and com-pared proven and new FT-processes with Lurgi’s alternative route MtSynfuels®. Tables 5 and 6 are taken from this paper. Their comparative eco-nomic evaluation is based on the following as-

sumptions: Table 5. Comparison MtSynfuels® vs. FT-Synthesis: Product Slate and Properties

Table 5 Product Slate MtSynfuels® FT Synthesis Naphtha : Kero+Diesel (max.) 1 : 2.3 – 1 : 6 Gasoline : Kero+Diesel 1 : 8 Product Properties 3)

Specification (Europe from 2005) Gasoline -Aromatics -Benzene -Sulphur -Olefins -RON 2) -MON 2)

vol.% vol.% ppmw vol.%

max. max. max. max.

35 1 50/10 1)

18 91/95/98 82,5/85/88

11 << 1 <<1 6 92 80

< 1 << 1 < 1 > 30 < 40 < 40

Diesel -Polyaromatics -Sulphur -Cetane No.

vol.% ppmw

max. max. min.

11 50/10 1)

51

<< 1 << 1 >52

< 1 < 5 > 70

1) Diesel with 10 ppmw sulphur has to be available on the market 2) RON / MON for Regular Gasoline / Euro-Super / Super – Plus 3) Properties of FT-naphtha

Plant location: Middle East; plant capacity: 50,000 bpd products; NG Price: 0.50 US$/MMBtu Depreciation: 10 % for ISBL, 5 % for OSBL; Return on Investment (ROI): 10 %; Total Capital Investment includes total plant capital (ISBL+OSBL) plus 20 % for other project cost, year 2000; Cost of Production includes depreciation and 10 % ROI.

The table shows that MtSynfuels® compares well with existing FT plants. Admittedly it lacks full commercialisa-tion, but so do most of the ultra-modern FT processes discussed currently. In contrast to these, MtSynfuels® is proven in three of four steps with the demo unit for the third step (MTP®) having confirmed the lab results by a 11,000 hours test run.

Table 6. Comparative Economics - Cost of Production Estimate

Table 6 MtSynfuels® existing FT1)

Total Capital Investment Total Plant Capital

1,181 MM $(€) 19,680 $(€)/bpd

1,671 MM $ 27,856 $/bpd

Figure 6. Gas Refinery via Methanol - Lurgi’s MtSynfuels ®

Olefin Production

Olefin Oligo - merisation

Gasoline 685 t/d

LPG 579 t/d

Kero/Diesel 5,438 t/d

H 2 ,55 t/d,from Methanol

synthesisWater recycle

Hydrocarbon Recycle

Methanol 15,000 t/d

Product separation

+ MD Hydrogenation

Hydrocarbon Recycle

Process water: 7,902 t/d can replace raw water

Olefin Production

Olefin Oligo - merisation

Gasoline 685 t/d

LPG 579 t/d

Kero/Diesel 5,438 t/dKero/Diesel 5,438 t/d

H 2 ,55 t/d,from Methanol

synthesisWater recycle

Hydrocarbon Recycle

Methanol 15,000 t/d

Product separation

+ MD Hydrogenation

Hydrocarbon Recycle

Process water: 7,902 t/d can replace raw water


NG to Process (LHV) Cat. & Chemicals Utilities

3.82 $(€)/bbl 7.64 MMBtu/bbl 2.19 $(€)/bbl 0.28 $(€)/bbl

4.22 $/bbl 8.44 MMBtu/bbl 1.53 $/bbl 0.8 $/bbl

Cost of Production + ROI 22.47 $(€)/bbl 28.68 $/bbl Market Prices 2)

- Gasoline [$/bbl] - Diesel [$/bbl]

Western Europe 56.9 48.3

US Nymex 51.5 53.6

1) ChemSystems 2001 2) Corresponding Crude Oil Price: about 42 $/bbl

From Gas to Petrochemicals

It has been shown above that propylene produced via MTP® competes well with cracker-derived product. In more general terms it develops that the chain of Lurgi’s technologies described here provides an alternative route to pet-rochemicals. Almost all steps are technically proven and the economic competitiveness mainly depends on the natural gas

price. This again follows from market pres-sures and the need or willingness to monetise gas reserves.

Figure 7 shows how the conven-tional cracker route from crude oil through olefinic and aromatic intermediates to highly valued petrochemical products is complemented -and replaced possibly- by “gas-to-methanol-and-others” processes. There is even the possibility to use coal as the primary feedstock for this methanol-to-petrochemicals route, an alternative seri-ously considered in the PR China which lacks large oil or gas reserves but has an abundance of coal.

Conclusions

There are abundant natural gas reserves providing low cost feedstock for methanol production and aiming at bet-ter use of natural resources especially in the case of associated gases being flared. DME and Propylene produced from methanol will increase the value of natural gas considerably and offer an exciting potential of growth and a high earnings level. Lurgi’s MegaMethanol® technology can bring down the net methanol production cost below US$ 50 per ton, wherever low cost natural gas is available. This opens up a completely new field for downstream products like DME, propylene and syn-fuels.

Based on simple fixed-bed reactor systems, conventional processing elements and operating conditions including

commercially manufactured catalysts, Lurgi’s MegaDME, MTP® and MtSynfuels® technologies provide attractive ways to "monetise“ natural gas.

Driven by the excellent market prospects and additional environmental aspects, Lurgi has developed its own

technology chains starting from natural gas via methanol to DME or propylene and polypropylene, based on the combina-tion of highly efficient concepts at low investment costs. In the next step these concepts lead to gas-based refineries and gas-based petrochemicals. This brings us back to the introduction where Figure 1 already presented and summarised the gas to chemicals routes. With the exception of FT and MTO which are offered as licensed technologies, all others de-picted here are proprietary technologies – a direct result of the high importance Lurgi always attached to natural gas and syngas conversion. MtPower depicts the utilisation of methanol and DME as energy carriers, made possible by the low production costs associated with the “Mega-plants”.

Eventually, financial, strategic and political interests will determine the ultimate selection of any “gas-to-value”

technology. The task of the engineering company is to provide as many attractive alternatives as possible to accommo-date for all sorts of local conditions. With the technology portfolio described above Lurgi is up to this challenge.

Figure 7. Gas-based Petrochemistry

OILconventional route

Natural GasAssociated Gas“Stranded Gas”emerging route

COALfuture route ?

Feedstock

AromaticsBenzeneTolueneXylenes

OxygenatesAlcohols, Ethers,

Esters, Acids,Aldehydes

Intermediates PetrochemicalProducts

OlefinsEthylene

Propylene

PolyolefinsPE, PP

Acrylates

PolycondensatesPC, PET,

PBT

Solvents

FuelsFuel additives

Syngas Methanol

Cracker

MTO

Lurgi‘sMegaSyn

Lurgi‘sMTP®

Lurgi‘sMTC

LurgiMegaMethanol®

OILconventional route

Natural GasAssociated Gas“Stranded Gas”emerging route

COALfuture route ?

Feedstock

AromaticsBenzeneTolueneXylenes

OxygenatesAlcohols, Ethers,

Esters, Acids,Aldehydes

Intermediates PetrochemicalProducts

OlefinsEthylene

Propylene

PolyolefinsPE, PP

Acrylates

PolycondensatesPC, PET,

PBT

Solvents

FuelsFuel additives

Syngas Methanol

Cracker

MTO

Lurgi‘sMegaSyn

Lurgi‘sMTP®

Lurgi‘sMTC

LurgiMegaMethanol®


Note on cost estimating / costing studies (Disclaimer)

Even the most exiting new technology will remain “l’art pour l’art” if it cannot prove its economical viability and attrac-tiveness for operator and investor. In some cases -like MegaMethanol® here- success is already proven in the market. For the newest technologies just entering commercialisation, economics are usually demonstrated by thorough engineering and costing studies. Results of those have been published in earlier papers and are discussed here also – with one impor-tant caveat:

Because of the current volatility of steel/equipment prices and of currencies themselves it is next to futile to give general-ized costing figures like USGC/ARA/WEU. Each project will have to consider its exact local conditions, physically, finan-cially and currency-wise – locking them in at a certain point in time.

To reflect this uncertainty we have refrained from simply “inflation escalating” our studies. Instead, we give cost ranges as defined by the two lead currencies, US$ and Euro (€). With the relation between them as of January 2005 the nominal costs in US$ mark the low end of the range and the costs in Euro mark the high extreme. This is visualized by giving both currency symbols in the relevant tables above. Real projects will have differing portions of deliverables from either cur-rency zone, so they will fall between the extremes thus defined.

REFERENCES

Cedigaz: “The 2003 Natural Gas Year in Review”, April 2004, www.cedigaz.com

Th. M. Quigley and Th. H. Fleisch: “Technologies for the Gas Economy”, EFI – Gas to Market Conference, San Fran-cisco, October 11 – 13, 2000.

S. Streb and H. Göhna: “MegaMethanol® - paving the way for new down-stream industries”, World Methanol Conference, Copenhagen (Denmark), November 8 – 10, 2000

W. Boll and W. Liebner: “Lurgi’s outlook on DME technologies”, DME 1 – First International DME Conference, Paris, France, October 12 – 14, 2004

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

H. Koempel, W. Liebner: “Gas to Liquids? Gas To Chemicals? Gas to Value!”, ERTC Petrochemical Conference, Amsterdam, February 20-22, 2002

M. Rothaemel, H. Koempel, W. Liebner: “Progress Report on MTP with focus on DME”, AIChE Spring National Annual Meeting, New Orleans, April 25-29, 2004, Session: Olefins Production

lurgi gas to chemical.pdf

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