Photo: Flickr, CC
Pollution MachinesBig cargo ships are basically air pollution machines. Most of them have very dirty engines, burning the dirtiest kinds of fuel, and doing so in mostly unregulated waters. It's no wonder that by some estimates just 1 cargo ships produces as much air pollution as millions of cars. What can be a done? A few things, one of them involving putting water in the fuel. Yes, it sounds counter-intuitive, but it just might work. Read on for the details.
Photo: Flickr, CC
First, the Problem
"Research by James Corbett of the University of Delaware estimates that soot from ships' diesels contributes to 60,000 deaths from heart and lung disease every year." And that's just the deaths; there are also all kinds of health problems that don't cause death, the loss of productivity and material damage, and the damage to animals and plants.
The (Potential) Solution
What creates most of the air pollution is incomplete combustion. For example, the carbon in the fuel ends up combining with nitrogen instead of oxygen.
Though it sounds bizarre, mixing water into the fuel helps it to burn better. The heat of combustion breaks water molecules up. The resulting hydrogen atoms help to split hydrocarbon molecules, making them more combustible, while the oxygen released goes on to combine with the carbon, ensuring that more of it burns. [...]
His answer is to use a surfactant. [...] a mixture of oleic acid (a fatty acid found in various vegetable oils) and nitrogen-containing compounds called amines. This mixture dissolves readily in diesel fuel and binds water to it without any need for stirring. The water droplets themselves can be as small as a nanometre (a billionth of a metre) across. That they are so small helps stabilise the emulsion. The result is, in effect, a liquid sponge, and means the mixture can be stored indefinitely, like ordinary diesel, without risk of separation.
The result, when it is burned, is the near-complete abolition of soot, and a reduction of up to 80% in nitrogen-oxide emissions. The surfactant itself also burns without creating emissions beyond water, carbon dioxide and nitrogen.
80% without having to change all the engines out there would be fantastic! Let's hope that if it works well in tests, that it will be deployed rapidly. But it's still just a step along the way. The real goal is to ship goods without using fossil fuels at all.
More on Air Pollution
The Port of NY/NJ Will Replace Dirty Old Diesel Trucks to Slash Air Pollution
EPA Wants to Clean Up Large Ocean-Going Ships
"Just 15 of the world's biggest ships may now emit as much pollution as all the world's 760m cars"