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Highlights of Japan Coal Week, 9-13 September

Over here, in Tokyo for an ExCo meeting later this week, we’ve had NEDO’s International Gasification Symposium to keep us alert after our flight out. Three of us (Geoff, Kyle and myself) came out on a Virgin Atlantic flight arriving in the morning the day before. The A340-600 plane was smooth and quiet in the front cabin.The best bit was seeing the Northern lights for the first time. The funny, angled seating arrangements that Virgin have meant annoyingly that you could hardly see out normally, but, when the seat was turned into a flat bed it, was possible to get to the window more easily by using contortions. The curtain-like aurorae changed quite rapidly and were a delight to watch, even though it was not possible to see any colour in them through the window.

All three of us looked sufficiently shifty to be picked out to have our bags searched by customs upon arrival. Fortunately, nothing nasty had been smuggled into them. The Express rail link to Tokyo from Narita airport was very clean and punctual. It’s always fun to see something a bit unusual: a nice touch was the rotating pairs of seats: with a flick of the wrist, the cleaner turned them to lock facing forwards before we climbed aboard.

By now joined by Andrew upon arrival in Tokyo, we reached the Hotel Okura. This is one of those big places with the lobby not on floor 1, but on level 5. However, confusingly, it looks as though it’s pretty much at ground level. Considering that Tokyo is pretty flat, I find that a bit strange, particularly as my room was lower, on floor 4, yet clearly miles above the lovely Japanese garden. I was told that the two alternative  breakfast restaurants were reached, respectively, by going down to level 1F, or up to level 1F (yes, 1F again) in the connected annexe. I might be a bit dim (come to think of it, a not very pleasant stranger back home not very long ago did tell me I had nothing between the ears), but I reckon anyone might find that confusing, especially after a 12 hour sleepless flight. I think the whole hotel is a real-life Escher diagram.

There was time after arrival for two of us to fit in a trip to see the Senso-ji Buddhist temple which was busy, but well worth seeing.

Senso -ji Temple, Tokyo

The symposium had four plenaries, including one from Andrew. As one would expect, his was entirely focused on what it was supposed to be on – gasification: some of the others had rather a lot of extraneous material. An oddity was the panel session, at which the results of the Japanese coal gasification programme were discussed. There were 12 (yes, really twelve) panellists, and they all presented. By the time the moderator had made his introductions and asked questions, there was actually time for only a few questions at the end of the afternoon. But that didn’t matter: I think only one was asked at the very end. Among other stuff, there was information on the oxygen-blown IGCC project with CO2 capture (CoolGen) under construction at Osaki, intended to pave the way for integrated gasification combined fuel cell cycles (IGFC). There is total commitment here to the development of coal power generation using IGFC.

The reception in the evening, hosted by NEDO, had a generous buffet banquet with limitless supplies of food. It all looked very good. Being a nuisance, as ever, I had just vegetarian items of course – but clearly all was excellent, and everyone found it good. Our colleagues from EPPEI in China arrived in time for that.

Strangely, I was fully awake all night, but apparently Andrew and Kyle were also. The next day consisted of a site visit to the 250 MWe (gross) air-blown IGCC power plant, owned by Joban Joint Power Co. Ltd, at Nakoso in Fukushima Prefecture. It was quite a long journey, but not stressful, and we were made welcome. Before arrival, there was a lunch stop, with a good spread again, at a nice hotel at Nakoso. We had videos and a presentation, and, finally went on the tour. Because we started purely on the coach, and got out at first only to look into one of the covered coal bunkers, I became a little worried that we might not be shown a lot. But after more sitting aboard the coach, we did climb some steps to a level outside the control room where the combined cycle turbine was located, although it was completely boxed in and so not visible. The heat recovery steam generator and gasifier structures were clearly identifiable close by, but we could not enter them, so that was a little disappointing, though we did go into the control room afterwards. The unit operates commercially, and was running smoothly at 240 MW (gross). The plan to add a CO2 capture pilot plant has had to be abandoned because of earthquakes. The IGCC was damaged by the major earthquake and tsunami a few years ago but was quickly repaired. Greater damage came from a subsequent earthquake but that was made good also, so it was not clear why the pilot could not be continued with. At a final gathering, I asked what the cost of the plant was: it was Y73 billion. This is roughly 730 million US dollars. For 237 MWe(net), it gives about 3100 $/kW, but construction was completed a few years ago now. It was expected that a second, larger unit would be 33% cheaper and subsequent plants cheaper again.

Our ExCo meeting in the hotel followed on Friday, with, a nice cruise around Tokyo Bay  for the dinner in the evening. During the evening, Adolf Aumüller, our retiring ExCo chairman, was presented with a bottle of whisky by Jürgen-Friedrich Hake, our new chairman. The Tokyo Bridge Gate was impressive.

Presentation to Dr Adolf Aumüller (right) by Prof Jürgen-Friedrich Hake during ExCo dinner

Tokyo Bridge Gate

The meeting continued on Saturday morning, with a visit afterwards to the super-clean Isogo USC power plant. I had never been before, but felt that I knew it, because the Unit 1 was one of the star subjects of my case studies report for the IEA in Paris some years ago. At that time, Andrew had visited it to get the data for me. A second new unit has since been added. We had a very warm welcome at this attractive power plant.

REACT desulphurisation unit at Isogo

The most striking thing about Isogo’s performance is its achieved emissions. At the time we viewed them, the indicators in the control room, for Unit 1, showed SO2 and NOx concentrations of zero, while, for unit two, they showed 3 ppm and 8 ppm, respectively. These figures are quite amazing. A few other points:

Opposed wall firing, with 4 vertical spindle mills, 8 burners per mill

Minimum load from a unit is 210 MW (using 2-3 mills out of 4)

Full load can be reached on 3 mills with supplementary oil firing

The low cost of operation and high efficiency were emphasised. The emphasis at the time of the IEA study was the high availability.

More information is in the 2007 report, obtainable free from the IEA website at: http://www.iea.org/publications/freepublications/publication/fossil-fuel-fired-power-generation.html

One of the stages of the LP turbine is to be replaced after failure of a blade; the stage has been removed. Output is still 599 MW, and efficiency is slightly reduced. The unit was off for six months before it could be returned to service. Some cooling water had reached the water-steam circuit but damage had been relatively limited due to quick action when the failure occurred.

Tomorrow, we set off for Shanghai for the Upgrading power plants workshop. Kyle will take over the blogging on that event.

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