Research Project Team on Emerging Gas Technology

Outline of the Research Team

The research project team on emerging gas technologies was set up in February 2001 to conduct research on technologies for transportation, storage, chemical conversion, and utilization of natural gas.
Current R&D themes address the subjects related to Gas To Liquids (GTL), Natural Gas Hydrates (NGH), and Dimethyl Ether (DME). It is considered that these are promising technologies for developing medium and/or small scale stranded gas reserves.

(1) GTL Technologies
Outline
An economic development of marginal gas fields with small recoverable reserves is considered as a key issue for oil and gas upstream business. To provide a solution on it, Japan Oil, Gas and Metals National Corporation (JOGMEC) has been making efforts focusing on the development of the new technology of natural gas utilization using GTL since the year of 1998.
JOGMEC is aiming at the development of the catalysts and the process, which are more economical than the existing ones to pave the way for monetizing the stranded gas reserves.

Oil produced by JOGMEC GTL process

In the fiscal year of 1998, Japan National Oil Corporation (JNOC) has started the research on GTL technology that utilizes CO2 contained in natural gas effectively. Our process consists of syngas (H2 and CO) production process and FT synthesis process, and we have developed catalysts for syngas production and for FT synthesis respectively, which reached the midterm target set initially in the fiscal year of 1999. In the fiscal year of 2000, we conducted research to overcome the technical requirements left before stepping up the next pilot phase (2001-2004). And then we determined the construction site for the pilot plant and designed it in the same year. In the fiscal year of 2002, we conducted commissioning test at pilot plant located at Yufutsu in Tomakomai-city, Hokkaido JAPAN, and started the pilot plant tests for more than two years. Pilot plant recorded the first GTL production from natural gas in JAPAN in November 2002. The plant can produce 7 BPSD crude GTL oil at maximum. The tests successfully completed in October 2004, and satisfied all the technical requirements at the pilot plant level.

Features of GTL process
JOGMEC GTL process could eliminate the following units:
1. CO2 removal unit
Our process use CO2 effectively in the syngas production process.
2. Air separator
Our process does not use the oxygen as a source of syngas production.
3. Syngas conditioning unit
Our syngas production process can produce syngas suitable for the FT process in one pass (H2/CO=2).

Under the conditions of relatively small production scale, which is less than 15,000 BPSD, and CO2 in the range of 10 to 40 mol% contained in the feed natural gas, our process has a possibility to be more advantageous than other conventional processes.

1. Construction and operation of GTL pilot plant [JOGMEC, JPX, CYD, CSM, NSC, IPX]
Evaluations of the performance of syngas and FT catalysts and the process were conducted at the pilot plant.

2. Evaluation of clean fuels from crude GTL oil [JOGMEC, JPX, CYD, CSM, NSC, IPX]
Crude GTL oil was produced by contacting syngas (H2/CO) onto noble and non-noble metal based FT catalysts. The difference of yield rates of light oil and heavy oil existed in case of producing GTL through noble metal and non-noble metal. The quantity of iso-paraffin is also different in each case.

3. Feasibility study to apply GTL as an option to develop gas fields [JOGMEC, IPX]
Two cases of feasibility studies were conducted. One is to place the GTL plant next to existing LNG base, and the other is to develop the offshore gas field by applying the GTL technology. Both cases were presumed studies. Conceptual design and cost estimation for GTL plants at the conceptual design level were finalized. Especially, the utilization of CO2 emission from combined LNG plant at the JOGMEC GTL plant was analyzed.

4. Improvement of synthesis gas production catalyst (non-noble metal) [JOGMEC, JPX]
The catalyst performance of reforming natural gas by CO2 and steam were investigated for syngas production through pilot plant test. The catalyst life test with natural gas was carried out for 950 hours. However the catalyst showed insufficient performance, developing simulation model and a study was conducted to analyze catalyst’s deactivation.
In the fiscal year of 2004, the improved catalyst showed stable performance during 1,100 hours.

5. Improvement of synthesis gas production catalyst (noble metal) [JOGMEC, CYD]
The properties of catalyst used at pilot plant test were examined, showing no deactivation during test. The stable operation for more than 6,600 hours was attained under target reaction conditions.
The rate of reaction and the heat transfer model were simulated with computational fluid dynamics (CFD) technique. Coefficients of equations in the model were adjusted by using the pilot plant data.

6. Development of noble metal based catalyst for FT synthesis [JOGMEC, CSM]
The target values of catalyst’s performance were almost attained at pilot plant test. Method of on-site reduction by measuring consumption of hydrogen was verified.
In the fiscal year of 2004, CO2 resistance of catalyst was successfully conducted in the pilot plant.

7. Development of non-noble metal catalyst for FT synthesis [JOGMEC, NSC]
The target values of catalyst’s performance were almost attained at the pilot plant test. Especially, full load operation was attained as 7.3 BPSD of crude GTL oil production, which was beyond design capacity of 7BPSD, and high liquid hydrocarbon productivity of more than 1,300 g/kg-cat・hr was also recorded. The stable operation for more than 2,200 hours was attained under target reaction conditions.

Summary

JOGMEC GTL Pilot Plant (Yufutsu, Tomakomai-city, Hokkaido, JAPAN)

In the fiscal year of 2004, JPX ‘s and CSM’s catalysts were tested at the pilot plant from April to July. CYD’s and NSC’s catalysts were also evaluated from July to October. From November to January 2005, dismantling study consisting of checking and analyzing materials is in progress. Finally, pilot plant will be pulled down completely in February 2005.
Finally, the stable operation for more than 6,600 hours was attained under target reaction conditions in syngas production section. In FT synthesis section target values of FT catalyst were almost attained. Remarkably, full load operation was attained 7.3 BPSD, and high productivity of more than 1,300 g/kg-cat・hr was also recorded. The stable operation was attained for more than 2,200 hours.

Abbreviations
JPX: JAPAN PETROLEUM EXPLORATION CO., LTD.
CYD: CHIYODA Corporation
CSM: COSMO OIL Co., Ltd.
NSC: Nippon Steel Corporation
IPX: INPEX Corporation

Reference
(I) M. Ihara, et. al: The Challenge of JNOC To Develop The New GTL Process, GAS-TO LIQUIDS VI Conference London, September 2003 (Vol.65, No.6)

(2) NGH Chain
Outline
Currently, a great deal of attention has been paid to hydrates as an effective gas transportation medium. NGH chain is expected to be suitable to the cases of small-medium gas fields where the investment in LNG facilities is not economical. Several Japanese private companies began the development on devices of each process in bench-scale, which composes NGH chain. And some governmental corporations such as JOGMEC are promoting these developments by financial supports.

Hydrates formation process is supposed to be the most important as its potential part saving the CAPEX compared to the LNG chain, and therefore each company focuses on the development of devices for hydrates formation process. Mitsui Engineering & Shipbuilding Co., Ltd. (MES) developed the bubbling/stirring-type formation reactor, Mitsubishi Heavy Industries, Ltd. (MHI) developed the water-spraying-type formation reactor, and JFE Engineering Corporation (JFE) developed a new hydrate formation system, which uses micro-bubbles with tubular reactor. It has not been judged yet which formation reactor is the most economically optimum. It should be judged from the viewpoint of heat removal, scale-up properties, and relations to other processes.

Shipping and re-gasification process are also under development by mainly MES.

In the near future, it is further needed to improve the precision of the feasible study along with an advance of the technology development. For that, it is important not only to consider an optimization of one process but also to understand an impact of one process on the chain and an optimization of entire chain.

1. Development of NGH Transportation Chain [MES]

NGH pellet

Utilization of gas hydrates for NGH chain is under investigation by some companies in Japan and U.K. Gas hydrate is regarded as an attractive material that stores lots of gas on relatively mild conditions. The final target of this research provides an option to develop the small and medium-sized stranded gas reserves.

MES considers that it is essential for economical transport and storage of natural gas taking advantage of natural gas hydrate pellet to be practiced under as high temperature as possible at the atmospheric pressure. Pellet is superior in the filling efficiency to other forms of natural gas at the time of transport and storage and in fluidity at the time of loading and unloading, and stability in dissociation is examined under storing temperature. In this research, MES designed and constructed the bench-scale plant (600kg/day) for pellet formation and re-gasification. In addition, production and re-gasification properties were investigated using mixture gas pellets.

2. Development of Natural Gas Hydrate Production Plant [MHI]

NGH dehydration equipment

A collaborative study on development of NGH production plant has been conducted for two years in order to evaluate NGH as an effective gas transportation medium. Some important subjects, such as enough concentration of gas in hydrate phase and long-term storage under atmospheric pressure, were successfully achieved with efficient combination of basic and engineering results. Attractive properties of NGH were certified and further economical feasibility studies should be followed.

3. Formation of Gas Hydrate Using Micro-Bubble [JFE]

Tubular-type hydrate formation reactor

Through basic experiments using propane as a proxy gas, JFE confirmed that a tubular-type hydrate formation system by use of micro-bubbles achieved higher production rate over conventional ones. A hydrate formation experimental facility using methane was designed and constructed in order to confirm high hydrate formation rate. As the result of operation the system showed higher performance compared to conventional systems. A static-mixer is used to generate micro-bubbles, and the reactor size is 250m long with internal diameter of 16.1mm. The design flow rate of water is 0.014m3/min and the maximum gas flow rate is 1.12Nm3/min. Experimental temperature and pressure is 1〜10℃ and 8 MPa at maximum, respectively. A method to analyze hydrate formation in the tubular reactor based on the conservation equations is also presented.

4. Development of an Advanced Hydrate-production Technology for Natural-gas Storage: Devising High-performance Production Processes Taking Account of Variable Crystalline Structures of Hydrates [Keio University]
Natural gas usually forms hydrates of structure I or structure II, depending on its composition as well as on the thermodynamic conditions under which it is brought into contact with water. If a large-molecule guest substance (LMGS), typically an oily substance 0.75−0.98 nm in molecular size, is added to the gas + water system, however, a hydrate of structure H may form at a pressure lower than that for forming structure-I or structure-II hydrate in the absence of any LMGS. A research group in Keio University has demonstrated, by laboratory-scale experiments, that the rates of gas fixation in forming structure-H hydrates may substantially exceed those in forming structure-I and structure-II hydrates, depending on the selection of the LMGSs. A joint research group representing Keio University, Ishikawajima-Harima Heavy Industries Co., Ltd., and National Institute of Advanced Industrial Science and Technology is formed for, from the fiscal year of 2004 to 2005, fundamental-to-engineering studies, aiming at establishing structure-H-based technology for NGH production. Included in the research are manufacturing and testing of laboratory-scale hydrate-forming apparatuses utilizing novel gas/LMGS/water mixing schemes.

(3) DME Utilization Technologies
1. Improvement of Lubrication Property for DME Diesel Engine [MHI]
On the research in the fiscal year of 2002, the actual diesel combustion tests were conducted, and excellent performance, that is the high thermal efficiency and the low emission, was confirmed. It became clear that the durability of fuel injection pump was a real problem to keep the excellent engine performance.
In the study of the fiscal year 2003, improvement of lubrication properties for DME fuel injection pump comes to the main subject. The countermeasures for the plunger stick and wear of fuel injection system were suggested, and the limit of wear was estimated from the viewpoint of the engine performance. Additionally, engine oil samples from DME diesel were analyzed and the properties of the engine oil suitable for DME diesel engine was discussed.

2. Development of Compact and High-Efficiency DME Fueled Fuel Cell (DME-FC) System [Osaka Gas Co., Ltd]

Fuel Processing Reactors (Reformer, CO Removal Reactor)

A compact and high-efficiency fuel-cell system that uses DME as fuel will be expected in the future. In the fiscal year of 2002, R&D was carried out to improve the durability and low-temperature activity of the DME reforming catalyst. In addition, an experimental DME reformer and CO remover were fabricated and their performance was evaluated to obtain engineering data. In the fiscal year of 2003, we manufactured a practical DME reforming catalyst on a trial basis, improved its durability and low-temperature activity, and evaluated its system performance by operating a 1 kW class fuel cell system with the DME reforming catalyst connected to it. Evaluation testing revealed that this system could stably produce reformed gas with 10 ppm or lower CO concentration, with a DME conversion rate of 99% or higher. Power generation testing, conducted with this system connected to a 1 kW class polymer electrolyte fuel-cell (PEFC) stack, revealed that inputting a specified amount of DME can stably output more than 1 kW of power. Market research for DME fuel cells was also conducted simultaneously.

3. Development of a Low-temperature DME Steam Reforming System for Fuel-cell Vehicles [Osaka Gas Co., Ltd]

Layout of external-heating type fuel processor

We had developed a 1 kW class reforming system for application to PEFCs that use DME as fuel, and a high-efficiency and high-selectivity copper-zinc-alumina catalyst for use in the reforming system. This study is to develop and evaluate an improved DME reforming catalyst for use in vehicle-use fuel-cell systems. All the developed components were integrated into a 5kW or 30 kW class DME reforming system, and its performance was evaluated, to establish a DME reforming catalyst and reforming system technologies for vehicle use. Two types of fuel-cell reforming systems would be evaluated under development for vehicle use: external-heating type and internal-heating type.

4. Demonstration of Low NOx Combustion Technology for DME Fueled Gas Turbine by Full Pressure Rig Test [Hitachi, Ltd.]

Multi Cluster Burner

We developed the coaxial jets cluster burner for fuel grade DME - a blend consisting primarily of DME with lesser amounts of methanol and water, which has an ignition temperature lower than the combustion air temperature. Combustion tests using full pressure test rig demonstrated that the proposed burner has high reliability, low NOx emission characteristics, high combustion efficiency, and multi-fuel flexibility through ignition to base load condition of 25MW class gas turbine.

5. Retrofit Application of DME fuel for Existing Boilers [MHI]

DME Flame

In promoting the popularization of DME, which is attracting attention as a clean fuel that can be made from natural gas, an urgent task is the early establishment of applied technology for commercial boilers that would serve as major sources of demand. The main fuels for existing domestic boilers are coal and oil, and it is expected that DME would be introduced for mixed combustion with these fuels. Accordingly, this project was for the verification of sole and mixed combustion performance of DME in large multi-burner combustion facilities, with field-testing of the requisite applied technology.

6. R&D of Heavy Duty DME Diesel Vehicle [COOP EV]
For medium- and large-sized diesel vehicles equipped with in-line fuel injection pump, four groups implemented tasks namely,
(1) Development and standardization of conversion kit for DME vehicle,
(2) Development of DME vehicle system,
(3) Optimization of fuel and development of filling system, and
(4) Establishment of voluntary standards of vehicle structure for the market application.

7. Practical Durability Fleet Test R&D of DME Vehicles [COOP EV]
We researched and developed DME vehicle, conducted fleet test on the official road as well as on the test course, and got some problems in the vehicle system.
Our aims are to look into the causes of these problems, find the countermeasures and optimize the quality of DME vehicle so as to be able to introduce it to the market. Also we developed the DME filling system by adding lubricity improver to DME to make DME fuel for automobile use. We improved its performance for the practical application. Meanwhile, we are preparing the draft of “Self-Management Standards of DME Vehicle and Its Structure,” which we will improve for effective use.

8. Technical Collaboration on the Process Development for the RIPI’s Ray OCM Technology
JOGMEC and the Research Institute of Petroleum Industry (RIPI) of Iran carried out the technical collaboration on the process development of natural gas converted into ethylene via oxidative coupling of methane (OCM) from December 2002 to June 2004. In this collaboration project, RIPI will develop the OCM fluidized bed catalysts, and JOGMEC will design the OCM fluidized bed reactor and the total process from natural gas into gasoline and evaluate the economics.

In the main results of the fiscal year of 2003, RIPI has developed the fluid OCM catalysts through four methods, and JOGMEC has developed the OCM reactor simulator.