America

Monday, April 07, 2014

Energy Wars: Fuel From the Sea



What's cooler than an "electromagnetic weapon at sea?" How about converting seawater to fuel?

Those wild and crazy Naval Research Lab folks and some Navy Reserve help have found way to convert sea water into hydrocarbon fuel. Proof of concept including fueling a model airplane for a test flight, as set out in "Scale Model WWII Craft Takes Flight With Fuel From the Sea Concept":
Navy researchers at the U.S. Naval Research Laboratory (NRL), Materials Science and Technology Division, demonstrate proof-of-concept of novel NRL technologies developed for the recovery of carbon dioxide (CO2) and hydrogen (H2) from seawater and conversion to a liquid hydrocarbon fuel.


Fueled by a liquid hydrocarbon—a component of NRL's novel gas-to-liquid (GTL) process that uses CO2 and H2 as feedstock—the research team demonstrated sustained flight of a radio-controlled (RC) P-51 replica of the legendary Red Tail Squadron, powered by an off-the-shelf (OTS) and unmodified two-stroke internal combustion engine.

Using an innovative and proprietary NRL electrolytic cation exchange module (E-CEM), both dissolved and bound CO2 are removed from seawater at 92 percent efficiency by re-equilibrating carbonate and bicarbonate to CO2 and simultaneously producing H2. The gases are then converted to liquid hydrocarbons by a metal catalyst in a reactor system.

"In close collaboration with the Office of Naval Research P38 Naval Reserve program, NRL has developed a game changing technology for extracting, simultaneously, CO2 and H2 from seawater," said Dr. Heather Willauer, NRL research chemist. "This is the first time technology of this nature has been demonstrated with the potential for transition, from the laboratory, to full-scale commercial implementation."

CO2 in the air and in seawater is an abundant carbon resource, but the concentration in the ocean (100 milligrams per liter [mg/L]) is about 140 times greater than that in air, and 1/3 the concentration of CO2 from a stack gas (296 mg/L). Two to three percent of the CO2 in seawater is dissolved CO2 gas in the form of carbonic acid, one percent is carbonate, and the remaining 96 to 97 percent is bound in bicarbonate.

NRL has made significant advances in the development of a gas-to-liquids (GTL) synthesis process to convert CO2 and H2 from seawater to a fuel-like fraction of C9-C16 molecules. In the first patented step, an iron-based catalyst has been developed that can achieve CO2 conversion levels up to 60 percent and decrease unwanted methane production in favor of longer-chain unsaturated hydrocarbons (olefins). These value-added hydrocarbons from this process serve as building blocks for the production of industrial chemicals and designer fuels.

In the second step these olefins can be converted to compounds of a higher molecular using controlled polymerization. The resulting liquid contains hydrocarbon molecules in the carbon range, C9-C16, suitable for use a possible renewable replacement for petroleum based jet fuel.

The predicted cost of jet fuel using these technologies is in the range of $3-$6 per gallon, and with sufficient funding and partnerships, this approach could be commercially viable within the next seven to ten years. Pursuing remote land-based options would be the first step towards a future sea-based solution.

The minimum modular carbon capture and fuel synthesis unit is envisioned to be scaled-up by the addition individual E-CEM modules and reactor tubes to meet fuel demands.

NRL operates a lab-scale fixed-bed catalytic reactor system and the outputs of this prototype unit have confirmed the presence of the required C9-C16 molecules in the liquid. This lab-scale system is the first step towards transitioning the NRL technology into commercial modular reactor units that may be scaled-up by increasing the length and number of reactors.

The process efficiencies and the capability to simultaneously produce large quantities of H2, and process the seawater without the need for additional chemicals or pollutants, has made these technologies far superior to previously developed and tested membrane and ion exchange technologies for recovery of CO2 from seawater or air.
- See more at: http://www.nrl.navy.mil/media/news-releases/2014/scale-model-wwii-craft-takes-flight-with-fuel-from-the-sea-concept#sthash.2gphEDJC.dpuf
So, let's see - with a large enough ship with a large enough plant on it, you could fuel the gas turbine powered fleet and its aircraft for . . .

Ashore? Making fuel from seawater? Why that's enough to help everyone with ocean access toward energy independence . . . I assume a small nuclear power plant could provide the energy to drive this process . . .

More from Physics.org. Might help with countering ocean acidification, too.

And about this from India's Economic Times "game changer" :
The development of a liquid hydrocarbon fuel is being hailed as "a game-changer" because it would signficantly shorten the supply chain, a weak link that makes any force easier to attack.

The US has a fleet of 15 military oil tankers, and only aircraft carriers and some submarines are equipped with nuclear propulsion.

All other vessels must frequently abandon their mission for a few hours to navigate in parallel with the tanker, a delicate operation, especially in bad weather.
***
Dr Heather Willauer, an research chemist who has spent nearly a decade on the project, can hardly hide her enthusiasm.

"For the first time we've been able to develop a technology to get CO2 and hydrogen from seawater simultaneously, that's a big breakthrough," she said, adding that the fuel "doesn't look or smell very different."

Now that they have demonstrated it can work, the next step is to produce it in industrial quantities. But before that, in partnership with several universities, the experts want to improve the amount of CO2 and hydrogen they can capture.

"We've demonstrated the feasibility, we want to improve the process efficiency," explained Willauer.
Way, way cool.


No comments:

Post a Comment