BS-VI can be used in older vehicles as well
Business Line, Delhi   24-Mar-2020

While a clear and transparent policy framework with stipulated time targets laid the foundation, concerted execution by oil marketing companies (OMCs) and auto-makers galvanised the entire journey through upgradation of fuel quality and engine technologies respectively,” said Dr SSV Ramakumar, Director (Research & Development), IndianOil.

In conversation with BusinessLine, Ramakumar said, “As I am speaking with you, at IndianOil, certification of BS-VI fuel quality at all its terminals, depots and nozzles (of more than 27,500 fuel stations) has been completed, barring a very few number of outlets in Leh & Ladakh. I am sure other Oil Marketing Companies are also exactly on the same page.” Excerpts:


How difficult was the task to upgrade refineries, given the stringent deadline?

BS-VI is an ultra-clean fuel with stringent fuel quality parameters — sulphur content is 10 parts per million (ppm) — which will permit the use of advanced after-treatment devices (ATDs) required for reducing harmful exhaust emissions like CO, HC, NOx and particulate matter.

The upgradation of the refineries to achieve this fuel was a massive exercise, both in terms of technology and capital investment. A major technology involved is deep desulphurisation of both gasoline and diesel streams. As desulphurisation is essentially done through hydrogen, each refinery had to go for massive revamp/creation of additional hydrogen generation units.

While monetary investment is humongous, availability of requisite vendors for fabrication and construction to meet the stringent time targets was a severe strain on refinery operational expenditure in terms of hydrogen consumption, catalyst change, increased fuel and losses because of more secondary refinery units and space to carve out new process units in land-locked refineries.

The new BS-VI emission standards, combined with fuel economy regulations, call for a new set of lubricants used in both petrol and diesel-driven vehicles. Catalytic converter compatibility is the major driving force in upgrading lubricant formulations, which will ensure sustained emission reduction capabilities and fuel economy while delivering regular lubricant functions.

All the OMCs, who are also the sellers of lubricants, have upgraded their product portfolio and today these new-gen lubricants are readily and easily available in the market.


Can BS-VI fuels be used in non-BS-VI vehicles?

There has been much speculation on the compatibility of existing vehicles with new fuels. It is fully safe to use BS-VI fuels in all categories and models of older vehicles.

Studies have revealed that there is absolutely no issue with the use of BS-VI fuels in existing BS-IV or older vehicles.

Critical properties of diesel fuel related to engine durability, such as distillation, lubricity, are maintained as in BS-IV levels.

The use of BS-VI fuels in existing vehicles will lead to marginal emission benefits. Since the sulphur levels in this fuel are lower, the particulate matter emissions from diesel vehicles are expected to decrease marginally, as the sulphur compounds in the exhaust act as a precursor for particulate formation.

Studies indicate that the particulate emissions from old vehicles can reduce up to 20 per cent with the use of BS-VI fuels.

Further, the reduction in fuel sulphur can also marginally improve the efficiency of catalytic converters fitted in the old vehicles.

Another feature of BS-VI fuels that may reduce particulate emissions is the concentration of some organic chemicals such as poly aromatic hydrocarbons (PAH), which have been reduced from BS-IV levels. For the same reason, the carcinogenicity of vehicle exhaust emissions is also slated to be reduced with BS-VI fuels.