Breaking the shackles of oil

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Another way The Indian government can cut down on its oil bill by using methanol and DME, Photo: AFP
Another way The Indian government can cut down on its oil bill by using methanol and DME. Photo: AFP

For India, ISIS’ attack on Iraq could not have come at a worse time. The Indian economy has been in a tailspin for four years. The Narendra Modi government has come to power on the promise of reviving economic growth. But before it has even had time to settle down, events in the Middle East — over which India has no control — have begun to make it harder by the day for Modi to redeem his promise to the people.

ISIS’ attack has been met with only dithering responses from the western powers that made it possible. The prospect of a prolonged struggle has already pushed oil prices up by $4-7 a barrel. The exchange rate for the rupee is sagging once more, and the two developments together will inevitably push up the cost-of-living index. This will give a fresh lease of life to those who insist that bringing inflation down must take precedence over reviving growth, so interest rates must remain high and money supply tight.

India may overcome this challenge as it has overcome others. But with jihadi Islamists on the rampage, this is not the last oil shock it is likely to face. The question that Modi, and indeed all of us, need to ask ourselves is this: How long can a country that is home to one-sixth of the world allow its future to be controlled by events that it cannot control?

This question would have been rhetorical had there been any other source of transport fuels. But ethanol, the only alternative that the world is using today, has proved a non-starter. Thirty five years after Brazil first began blending it with petrol, the countries that tried to follow suit have learned that ethanol can never make more than a minor dent in their dependence on imported oil and gas, and that it can only do that at a prohibitive human and political cost. This is because ethanol has been successfully produced only from food crops like sugar, corn and soya beans. A much-touted alternative — cellulosic ethanol — to be made by fermenting the fibrous matter in biomass, has so far proved a resounding failure.

In India, ethanol has even less of a future because we have no food crops to spare. The ethanol we make, therefore, comes from molasses, and the liquor industry has been picking most of it up for decades. Although the UPA government mandated the blending of 5 percent of ethanol more than five years ago and raised its target to 10 percent last year, not surprisingly, the highest we have achieved so far is just 3.8 percent.

The far better and more versatile alternative to petrol is not ethanol but methanol. Methanol was first used as a transport fuel by Germany during World War II. In the 1960s, its superior flame qualities and immensely greater safety in car accidents made it the prescribed fuel for most of the major automobile races in the world, like the Indianapolis 500 and the Monaco Grand Prix. It remained so for four decades until it was partially displaced by ethanol in 2007.

Its suitability for use as car fuel was tested with varying blends of methanol and petrol for close to 15 years and two million miles of running in California between 1990 and the early 2000s. General Motors and Chrysler developed ‘flexi-fuel’ engines to run on these blends. Today, it is increasingly being adopted by China as a replacement for petrol in the form of m-85, a hybrid fuel that is made up of 85 percent methanol and 15 percent petrol.

What is better still, while ethanol can only replace petrol, the industrial process that yields methanol can also yield di-methyl ether (DME), which is an excellent substitute for diesel.

In a recently concluded study in Sweden, automaker Volvo ran 10 of its giant, 60-tonne trucks for two years on DME alone. After more than 100,000 km of use, it found that the trucks not only produced 95 percent less carbon in their exhaust, but that their engines had suffered less wear and tear than when they were run on diesel. The drivers also reported that their trucks were quieter and accelerated more quickly on DME than diesel.

Finally, DME can also replace lpg as a cooking fuel because it is a heavy condensate gas with almost exactly the same density as lpg. This would eliminate a large chunk of the oil subsidies that are weighing down the Centre’s fiscal deficit.

The technology required to produce methanol and DME from biomass is not fermentation but gasification. In gasification, organic matter is burned in an insufficient supply of oxygen. The shortage of oxygen prevents complete combustion. This reduces the output of carbon dioxide and generates carbon monoxide and hydrogen instead. These invaluable gases are the basic building blocks of the entire petrochemicals industry. They can easily be combined in the presence of catalysts to yield not only methanol and DME. What is more, taking advantage of a widely- used industrial process called the Fischer Tropsch synthesis, they can be, and are being, converted into diesel, aviation turbine fuel and petrol as well.

Several technologies for obtaining these gases ( jointly called synthesis gas) from virtually any form of biomass, and converting them into transport fuels are now fully market ready. As many as 200 plants are under construction all over the world to generate power or produce methanol, DME, bio-diesel and aviation turbine fuel from municipal solid waste via a very high temperature process called ‘plasma gasification’.

Another process, developed and patented in Sweden, is producing these from ‘black liquor’ — a carbon-rich residue of the paper pulp industry that is currently being dried and used as boiler fuel to provide process heat for the paper plant.

India’s 11 million tonnes-a-year paper industry is well aware of this process and can make a significant contribution to the replacement of petrol and diesel with methanol and DME, but will only consider doing so after the government formally includes methanol among the fuels that can be blended with gasoline and fixes a price for its purchase by the oil marketing companies.

But the sector that can free India from the shackles of imported oil is the sugar industry itself, for the bagasse left behind after crushing sugarcane is among the finest feedstocks for gasification in the world. Modern sugar mills burn it in high-pressure boilers to produce process heat. Since the heat generated is four times what they need to make sugar, the mills use the balance to generate power for sale to the state grids during the 180 days of the cane-crushing season.

Switching from boilers to gasifiers will yield several additional benefits. First, in addition to the bagasse, the sugar mills will be able to use the sugarcane leaf and waste as additional feedstock for the gasifiers. This will more than double the amount of feedstock and allow the gasifiers and biofuels plant to be run for the entire year instead of during the cane-crushing season alone. Finally, since gasification produces 50 percent more heat than combustion, the extra power they are able to generate will allow the mills to produce not only the oxygen that gasification requires, but also sufficient hydrogen to double the output of methanol or DME. All in all, at current international prices of methanol and DME, co-production will enable the sugar industry to treble, possibly quadruple its sales revenue.

Arithmetic can be tedious, but it is worth suffering a little more ennui to grasp what this single change in a single industry can mean to India’s future: All the pilot studies carried out so far have shown that a tonne of air-dried biomass can yield between 0.5 and 0.6 tonnes of methanol or about three-quarters as much of DME.

The sugar industry currently produces over 100 million tonnes of bagasse. Fed into gasifiers with an equal mass of sugarcane waste, this is capable of producing enough synthesis gas to yield 100- 120 million tonnes of methanol or 75-90 million tonnes of DME. Used in flexi-fuel engines with 15 percent of petrol, the former can meet three times India’s current consumption of petrol. The latter can meet all of its current requirement of high-speed diesel. This would only be the beginning for there are billions of tonnes of garbage, and other crop residues, waiting in the wings.

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