New process offers hope for grounded KSRTC biodiesel buses

All Karnataka State Road Transport Corporation (KSRTC) buses running on biodiesel are now grounded. Reason: Fuel procurement problems.

But what if a fuel plant comes up right here with tonnes of used, redundant cooking oil supplied by thousands of hotels and restaurants in the city as raw material?

The city-based Mahatma Gandhi Institute of Rural Energy and Development (MGRIED) and Hotel Taj Vivanta showed a way out recently. Under a deal inked on World Environment Day, the hotel will supply 400 litres of used cooking oil every month to MGRIED’s biodiesel plant.

Could this model be replicated by KSRTC, which had proposed to build its own plant? Waste vegetable oils and animal fat besides other raw material such as palm sterene are used to make biodiesel. Far less polluting than fossil fuel, biodiesel is also cheaper than high speed diesel.

KSRTC had launched 11 bio-diesel buses in October, 2015, 10 of them run on Blend 20 (20% of biodiesel blended with diesel), without any modifications to the diesel engine, and one on Blend 100. The fuel was supplied from a plant in Rajahmundry, Andhra Pradesh, about 800 km away Bengaluru. However, the entire fleet was grounded in December 2016 as the supply stopped. Fresh tenders are being floated to find a new supplier.

Through a process called transesterification, the discarded cooking oil is turned into a useful raw material. As MGRIED executive director T V Mohandas explained, the process uses sodium hydroxide and methanol to produce bio-diesel, proven to be non-toxic and biodegradable. It emits lesser carbon-dioxide than fossil fuels.

The institute’s plant has a capacity to produce 50 litres of biodiesel daily. The fuel is used to operate a minibus and jeep, besides for research in its laboratories. Bengaluru has another small biodiesel plant on the GKVK campus with a daily capacity of 100 litres.

Making available tonnes of redundant vegetable oil from hotels across Bengaluru for bio-diesel production through appropriate channels could be a potential game-changer, indicated Mohandas. The waste oil from hotels currently finds its way to footpath food vendors.

However, reusing the oil is a health hazard. Experts say the unsaturated fatty acids get into the human system leading to complications.
DH News Service