Pressurized Oxy-fuel System has no Pollutants and Captures CO2

ThermoEnergy Corporation  (OTCBB:TMEN - News) is developing a pressurized oxy-fuel approach known as the ThermoEnergy Integrated Power System (TIPS) which is a process designed to produce energy (electricity, steam) from coal, with integral carbon capture as liquid CO2 and near zero air emissions. Pressurized oxy-fuel technology addresses two major issues affecting the future use of the country’s coal resource. These are:

1. Economic capture of criteria and toxic pollutants (such as mercury) from the diverse power and steam generators needed, and
2. Economic capture of CO2 from the larger power and steam generators used by utilities and large industrial facilities.

Once it is commercially deployed, TIPS will revolutionize the way the world generates energy from hydrocarbons. Based on reliable oxy-fuel chemistry, TIPS departs from the traditional oxy-fuel approach by pressurizing the entire combustion system.  Because the process operates at an elevated pressure it is able to use gas-to-liquid steam-hydroscrubbing to collect and remove pollutants, including NOx, SOx, mercury, particulates and CO2, and recover latent heat from water entrained or produced in the combustion process at efficiencies comparable to those of conventional large-scale combustion technologies. The pollutants are recovered via direct condensation and can be sold as commodity products. The pressurized oxy-fuel approach also enables CO2 to be recovered as a pressurized liquid through direct condensation. Emerging improvements to oxygen separation technology will significantly improve the economics of oxy-fuel processes.

TIPS PROCESS DESCRIPTION

TIPS process combustion takes place at pressures between 4.83 and 8.96 MPa. (700 and 1300 psia) Increasing the pressure of combustion shifts the temperature at which water, CO2 mercury and acid gases condense. The elevated pressure and condensation temperature process conditions enable the process to utilize heat transfer, mass transfer and liquid vapor equilibrium regimes well suited to capture of pollutants and CO2. Elevating the pressure enables the use of nucleate condensation at temperatures in the range of 262 to 303°C (503 to 577°F) in a heat exchanger that simultaneously recovers heat and condenses and captures pollutants. Two components of pressurized oxy-fuel technology central to achieving the twin goals of efficiency and pollution control are the air separation plant to provide oxygen under pressure, and the condensing heat exchanger to capture both pollutants and heat from the combustion gases.

Energy Efficiency Of The High-Pressure Oxygen Supply

Pressurized oxy-fuel firing of coal eliminates energy lost in the exhaust nitrogen by eliminating the nitrogen and recovers the latent heat of vaporization of both the produced and entrained water. In comparing the components of TIPS with a modern pulverized coal power plant, the capital cost of a conventional air separation plant used by TIPS is slightly less than the capital cost of the conventional desulfurizing unit for the pulverized coal plant.

The energy cost of separating air and pressurizing the oxygen is roughly 20% of the total energy contained in the coal. Therefore, improvements to air separation technology are especially significant to oxyfuel processes and fortunately new improvements are now entering commercial development. Emerging ion-transport membrane (ITM) technology is poised to revolutionize oxygen separation. DOE and major air separation companies estimate that capital and energy costs for oxygen separation plants will be reduced by roughly 35% compared to the traditional processes.

Condensing Heat Exchanger Recovers Heat And Captures Pollutants

The TIPS configuration enables one simple device, the condensing heat exchanger, to collect particulates, acid gases and mercury into a condensed phase that is roughly 2,500 to 3,500 times smaller than the volume of gas treated by conventional atmospheric pressure flue gas clean-up systems. The condensation heat transfer rates are so high that, once developed, the process may be less costly than current atmospheric pressure systems requiring particulate collection, desulfurizers, de-NOx and mercury abatement equipment.

ECONOMIC ADVANTAGES

TIPS enjoys numerous economic and environmental advantages when compared to conventional "clean coal" combustion technologies, such as the Integrated Gasification Combined Cycle (IGCC) process. TIPS is a straight-forward approach to power generation containing fewer unit operations and thus intrinsically more reliable. The economics of TIPS and IGCC are similar for a new large utility plants (excluding CO2 capture) using high-rank coal as a fuel. With CO2 as an added condition, IGCC cannot match TIPS economic performance in any category.

TIPS has superior projected economics for all other cases the company has examined including: subbituminous and lignite fuel, retrofit of existing coal plants, smaller power plants (5 to 100 MW), and industrial steam plants. TIPS provides the captured CO2 product as compressed liquid or solid (dry ice) ready for beneficial use or sequestration.

PROJECTS

In the most recent U. S. Government budgeting cycle, an aggregate of $2.3 million was authorized for TIPS research and development. ThermoEnergy is currently working with its grant collaborators to use this money to expedite the development of the technology. The Company's goals are to 1) partner with a key industry participant, 2) build a prototype facility, and 3) commercialize the TIPS process.

ThermoEnergy and the University of Nevada (Reno) have successfully concluded what was the first of three federal grants designed to fast-track the development of the Company’s advanced power plant design. The subject of the work performed by the University of Nevada Reno (UNR) was conducted under the US Department of Energy’s Biomass To Energy Program. The engineering data gathered during this research program will be added to the data gathered via the remaining two grants – a $300,000 DOE grant, previous post, and a $1,500,000 grant with the Alaska Energy Agency – which will allow the Company to design a large-scale TIPS demonstration plant.

The Company, along with the EPA Grant Administrator and the Alaska Energy Agency (AEA), made the decision to allocate most of the upcoming $1.5M federal grant toward the design, building and operation of the first working prototype of a TIPS power boiler. This system will be housed at the Canadian Energy Laboratory (part of CANMET) in Ottawa. AEA recently received notification from the US EPA that the grant application has been approved and will be funded pending notification of the members the State of Alaska congressional delegation. This prototype is expected to demonstrate TIPS zero air emission capability, along with CO2 capture and provide the engineering data necessary to design and build a large-scale demonstration unit.

Alex Fassbender, SVP for Engineering and Technology Development for ThermoEnergy, presented a technical paper on the TIPS process at the recently held 30th International Technical Conference on Coal Utilization & Fuel Systems, which can be found here.

The Swedish company Vattenfall is also building a oxyfuel pilot plant as was described in a previous posts and DOE is funding two other oxyfuel projects as noted here.

ThermoEnergy Corporation, Little Rock, AR

Comments

[Thomas]

Whoaa! Wery cool!

Pressurizing the oxygen probably takes less energy than compressing the CO2 after combustion. Not least because conventional oxygen separation units operate very cold, which reduces compression power requirement.

However, as a boiler-engineer, I am curious as to how they plan to contain such large volumes of gas at such high pressure..? That would probably mandate smaller units, which is not necessarily a bad thing.

[Apriterra]

Ok so what's the reality factor on this?

Why aren'y utilites falling over themselves to get this technology rolling?

[amazingdrx]

The reality? 40% efficiency (usual maximum for steam turbine electric generation)minus the 20% for separation and pressurization of the oxygen, equals a paltry 20% efficiency for the total conversion of coal to electricity from this system.

A coal fired fuel cell/turbine system has 75% efficiency.

Why aren't utilities and government favoring this much more efficient, much more cost effective technology?

Politics and corporate corruption is why. The Alaska congressional delegation is legendary in their pork procurement proficiency. The infamous Alaskan "bridge to nowhere" cost way more than the paltry few mill spent on this boondoggle.

http://dir.salon.com/story/news/feature/2005/08/09/bridges/index_np.html

[Paul Dietz]

Pressurizing the oxygen probably takes less energy than compressing the CO2 after combustion.

Um, why? There will actually be more oxygen molecules than CO2 molecules (remember, coal contains some hydrogen), and CO2 also has stronger intermolecular attraction than O2, which will reduce the work required slightly.

Not least because conventional oxygen separation units operate very cold, which reduces compression power requirement.

That cold isn't free, and if it really helped, you could chill the CO2 as well before compressing it.

[JJ]

Ya, where's the dirt, what's the down side. This article completely ignores balanced reporting showing the good, the bad and the ugly. $2.3 million authorized for R&D is chump change if this process is so great. It seems that we should outlaw all dirty coal plants and replace them with this process. Something stinks in this process -- what it is??

[amazingdrx]

I overlooked the rankine generator for harvesting waste heat which might boost
the efficiency 20%, but it's still a long way to the 75% of the coal fuel cell with gas turbine.

And he waste heat from the fuel cell could yield another 10 to 20% with infrared PV cells added around the cells.

[mcr]

amazingdrx: "the 75% efficiency of the coal fuel cell with gas turbine."

Its actually 60%.

Which is still far more efficient (as you say - no moving parts in the fuel cell)

Don't get too carried away.

And yes - something stinks in the above - either that or I haven't read it properly.

http://www.jupiteroxygen.com
I read this a few weeks ago - another project that sounds very very very similar on first inspection.

It's always wise to describe the limitations of a technology... and this needs to be done here.

[Udo Stenzel]

No pollutants?! Are you completely nuts? How is something that, for every gigawatt-year in operation, dumps 200.000 tons of heavy metal laced dust into a pond or an open landfill considered "pollutant free"?

[Jim from The Energy Blog]

Udo-You have to assume that the operators of such plants are environmentally resposible and do not dump their solid waste into "a pond or and open landfill." I would also hope that before permitting such a plant, a plan for disposing of this waste was a condition for operation of the plant.