CARBON CAPTURE & UTILISATION

Carbon capture and Utilisation technology may make economic sense

Carbon capture and utilisation (CCU)could be one of the best ways of combating climate change.

Passing carbon dioxide through slag left over from steel-making turns the waste product into a strong material that can be used for construction. Pumped into greenhouses, it provides a growing boost for crops. Put into tanks of algae, it can be used to make biofuels. Waste carbon dioxide can even be cleaned up to “food grade” and injected into fizzy drinks.

But these processes are rare — instead, carbon dioxide from power generation is normally simply vented into the atmosphere, where it contributes to global warming. When the gas is needed for an industrial process, it is manufactured from scratch.
The Carbon capture and utilisation (CCU) could be one of the best ways of combating climate change, by turning carbon dioxide from a waste gas into an integral part of industrial processes.

There are a few examples of the development of processes to use CO -2 to make synthetic diesel from carbon dioxide,  to manufacture cement using the carbon dioxide from power plants, and in several places around the world, algae is being cultivated that would absorb the gas and could itself then be used to make biofuels.

In  UK  where the carbon from power stations is liquefied and stored in depleted oilfields under the North Sea — but nothing into recycling carbon dioxide.

The group of researchers have developed a new class of catalysts for the conversion of CO -2 into commercially important cyclic carbonates, which can be used as electrolytes for lithium ion batteries; additives for petrol, diesel and aviation fuel; solvents; and in the production of polycarbonates and polyurethanes, and other commercial chemical processes.

Many of the processes envisaged for CCU require some energy input — but the report's authors note that this could be provided by renewable energy, especially when wind or solar plants are producing energy at times of low demand. In this way, producing fuels from CO -2 could effectively be a way of storing renewable energy in another form.

However, the costs are still high for many of the potential applications of waste CO -2— about 10 times too expensive in the case of algae, for example. Much more investment is needed to bring down the costs, and putting a sizeable price on carbon dioxide emissions would also help.

GSLV-12 Launch

GSAT-12 Launch

India notched another milestone in its space programme by successfully launching a heavy-duty rocket that placed a major communications satellite in space.

The PSLV blasted off successfully carrying the 1,410 kg GSAT-12 satellite from the spaceport. The satellite has a life span of about seven years.

With this, India added 12 more communication transponders to its space-based network.

The launch took place under a cloudy sky, with the Rs.95 crore rocket PSLV-C17 – measuring 44 metres in height and weighing 320 tonnes – soaring off into space with a roar.

It ferried the Rs.105 crore GSAT-12 having 12 extended C-band transponders – automatic receivers and transmitters for communication and broadcast of signals.

People perched atop of the nearby buildings too happily applauded as PSLV-C17 went up.

The GTO is an intermediate orbit from where normally communication satellites will be moved to its final geosynchronous orbit by firing the on-board motors.

The rocket’s navigation systems were powered by Indian-made advanced Vikram processors.

The GSAT-12 carries around 851 kg of fuel on-board to fire the motors. (A geosynchronous orbit is one directly above the earths’ equator. For an observer from the earth a satellite in geosynchronous orbit will seem motionless, stationary at one point in the sky).

The rocket placed the satellite in sub GTO with a 284 km perigee (nearest point to earth) and 22,020 km apogee (farthest point from the earth). The satellite was raised to 36,000 km apogee from 22,020 km.

The satellite will be useful for various communication services like tele-education, tele-medicine and for village resource centre.

The GSAT-12 satellite is also expected to serve the Very Small Aperture Terminal (V-SAT) sector. VSATs are used to transmit data like point of sale transactions or to provide satellite internet access.

The satellite will augment transponder capacity of Indian National Satellite (Insat) system which at present comprises of eight satellites — Insat-2E, Insat-3A, Insat-3C, Insat-3E, Insat-4A, Insat-4B (working at 50 percent capacity) Insat-4CR and GSAT-8 providing 175 transponders in the S, C, extend C and Ku bands.

The Indian space agency has leased 86 more transponders from various foreign satellites. It is estimated there is an unmet demand for 170 transponders.

ISRO used its third PSLV rocket variant – PSLV-XL – with longer strap-on motors with higher fuel capacity – to put the latest communication satellite in the space.

The other two rocket variants are the PSLV standard with 11.3 metres six strap-on motors and the PSLV Core Alone (CA) rocket without the six strap-on motors.

This is the second time ISRO has launched a rocket with this specification. The earlier one was for the Chandrayaan moon mission.

This is also only the second time ISRO is using a PSLV rocket for launching a satellite to be finally placed in geostationary orbit. The first satellite was Kalpana-1 (originally named as Metsat), a meteorological satellite launched in 2002.

The PSLV has an excellent success record since 1994, launching many Indian and foreign satellites.

ISRO planned to launch remote sensing satellite – Megha-Tropiques later this year.