Partners begin verification testing of Blue Tower staged reforming technology for bio-hydrogen production from sewage sludge
11 September 2012
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The HIT BusinessResearch Group intends to convert sewage sludge to hydrogen for fuel cell vehicles and stationary fuel cells. Click to enlarge. |
The Hydrogen Innovation Town (HIT) Business Research Group in Japan—including Japan Blue Energy Co., Ltd. (JBEC); Daiwa Lease Co., Ltd.; Toyota Tsusho Corporation; and Mitsui Chemicals, Inc.—has begun verification tests using sewage sludge to generate bio-hydrogen at JBEC’s Blue Tower new technology plant located at its development center in Izumo City, Shimane Prefecture.
The HIT Business Research Group is targeting the conversion of biomass (in this case, disposed sewage sludge) into hydrogen as a substitute for fossil fuels, utilizing JBEC’s proprietary Blue Tower staged reforming technology. The partners envision that the introduction of the technology to sewage treatment plants around Japan will facilitate supply of hydrogen to fuel cell vehicles (FCV) and stationary fuel cells (FC). Daiwa House Industry Co., Ltd. and Toyota Motor Corporation are participating in the group as observer members.
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The Blue Tower comprises three in-line vessels: preheater, reformer and pyrolyzer. Alumina balls serve as a heat carrier. Click to enlarge. |
The Blue Tower uses pyrolytic gasification and reforming to convert biomass to a gas with a high hydrogen concentration. The technology is based on the improvement of the original technology (“Blauer Turm”) of the German company DM2 (DM2 Verwertungstechnologien Dr. Mühlen GmbH & Co. KG).
One of the main features of the Blue Tower is its use of alumina balls as the heat carrier; the heat carrier is circulated orderly and repeatedly within the three core components of the tower: pyrolyzer, reformer and pre-heater. The heat carrier is heated by the flue gas from the combustor.
In the pyrolyzer, biomass material (woodchips, sewage sludge, etc.) is brought into contact with high temperature alumina balls to generate a biogas at about 500–600 °C. The generated pyrolysis gas is reformed at around 950 °C in the reforming section where steam is added to promote hydrogen formation via the water-gas shift reaction. Steam used in the reformer is pre-heated using hot producer gas.
Circulation of the alumina balls is highly efficient in heating core components and also effective in preventing and making controllable common plant equipment problems such as blockage caused by tar. The Blue Tower process runs uninterrupted and is completely autonomous without any external additional energy supply.
Past small scale tests have shown that the Blue Tower technology is successful in converting sewage sludge into gas with high hydrogen concentration, thereby confirming the potential of sewage sludge as a raw material of bio-hydrogen.
Through test runs at the verification plant, methodology and production of bio-hydrogen will be substantiated and followed by studies for a commercial scale bio-hydrogen production plant and a model business structure.
The economics of this are interesting.
Although the nominal price per kilogram may be higher than reforming natural gas, substantial costs are anyway incurred in treating sewage, so only the extra cost of producing hydrogen over and above the cost of treating the sewage needs to be imputed to the hydrogen.
Posted by: Davemart | 11 September 2012 at 02:34 AM
If you could kill two birds with the proverbial one stone, the energy required for treating sewage and the energy required for reforming it might be one and the same. That's a tremendous savings!
I'm not very clear on the reformation process. Does anyone have any insight on this?
Posted by: EVryman | 11 September 2012 at 05:38 AM
@EVryman;
You get way more energy from processing the sewage than it takes.
On reformation Wiki is good.
The bottom line is that if you want to run vehicles on natural gas or hydrogen, the greater efficiency of fuel cells means that you use a lot less than NG in an ICE car even after reforming and compression losses, which amoount to ~30%
Posted by: Davemart | 11 September 2012 at 06:49 AM
Looks promising. I wonder what the size of the resource is; is this a drop in the energy bucket, or could this produce a significant fraction of a nation's energy needs?
Posted by: Nick Lyons | 11 September 2012 at 07:48 AM
This is one of the applications where it makes sense to use hydrogen instead of something else. You're already starting with a chemical fuel, and hydrogen is the simplest molecule for the task of carrying energy.
If this process can use other feedstocks, such as torrefied and powdered municipal garbage, even better.
Posted by: Engineer-Poet | 11 September 2012 at 11:09 AM
@Nick:
The big one here is when they mention woodchips as a suitable source.
Novazyme argue:
"If you take just 20% of the agricultural and forest residue available in Europe, which can sustainably be taken away from the fields, you can make half of Europe's gasoline demands," he says.'
http://www.bbc.co.uk/news/business-19179419
As for sewage, or at least municipal waste, specifically:
'Poulsen and Hansen calculate that the energy potential tied up in municipal organic waste in Denmark is equivalent to 5% of the country's total energy consumption including transport. The Aalborg municipality represents about four percent of the Danish population.'
http://www.sciencedaily.com/releases/2009/11/091130103634.htm
So you might roughly think of sewage as able perhaps to power most public transport, but not private cars.
Posted by: Davemart | 11 September 2012 at 11:48 AM
Im interrested to buy sewage to put(after reformation and some specific specialized treatments) into my future hydrogen fuelcell car.
Posted by: A D | 11 September 2012 at 07:06 PM
Well from what I understand, sulfur is a major barrier to the catalysts of hydrogen reformers. I wonder how these guys plan to avoid the toxic effects of the sulfur rich sludge on the reformation process...
Posted by: EVryman | 11 September 2012 at 09:32 PM