Pirelli Researching the Use of Rice Husk Ash in Tyre Compounds

From an ecological point of view, the new Pirelli Cinturato P7 offers three headline benefits – a CO2 emission reduction of up to 4 grams per kilometre driven, 30 per cent lower noise emissions and a 4 per cent fuel saving. Pirelli’s clincher (particularly aimed at current and potential OE customers) is that it is already in position to meet the targets set by the new EU regulations that are due to take effect from 2011 and that it does this without compromising on wet or dry performance. However, none of this explains how the company is able to achieve these goals.

In mid-February, Pirelli gave details of how its 2009 – 2011 industrial plan means the company will have an increasingly “green” focus. In particular Pirelli committed to developing a series of new materials that for use in tyre compounds. One particular silica rich material is rice husk ash (RHA). Pirelli is already (as far as the technological requirements are concerned) in a position to use this material in tyre production this year. However, the material is currently the subject of a large scale viability study focusing on the availability of the kind of tonnages needed for tyre industral scale tyre manufacturing. Tyres & Accessories understands that Pirelli already has research and development teams in place in Brazil and the areas surround Milan, which just happen to be some of the best rice production areas in the world.

Rice Husk Ash has a number of benefits in terms of tyre production. Firstly, it is said to be considerably less costly (both financially and environmentally) as it is produced as a by-product in industrial-scale rice preparation. Here’s an example what this means: for every 1000 kg of paddy that is milled about of 220 kilos (22 per cent) of rice husk is produced, the rest is rice and bran. Rice producers commonly use this as fuel for furnaces used in the parboiling process necessary for the kind of easy cook rice that is so popular. The 55 kilos of ash that remain after the firing process are said to offer 85 – 95 per cent amorphous silica.

This also means that unlike bio-diesel there aren’t any ethical or philosophical dilemmas attached to this bio-product’s development – no food production space is being taken up for an industrial product. However, from the tyre industry’s perspective, perhaps the best benefit is in its wet grip/rolling resistance characteristics. While the product itself is mostly silica, RHA is said to offer marginally better performance in than the expensively and less environmentally produced silica tyre manufacturers currently use.

Tyre scrappage scheme

Pirelli also launched a tyre scrappage campaign in the Italian market. The self-funded scheme includes a fuel purchase contribution for anyone deciding to replace their tyres with an eco-compatible product. Pirelli’s scrappage scheme, something of a first in the tyre business, aims to sustain demand at a difficult time for the economy and stimulate the use of low environmental impact products for each segment of the automobile market, promoting substitution of tyres that are worn out beyond legal limits (equal to 1.6 millimetres of residual tread), in order to favour road safety.

The initiative was presented in Rome on 26 March by Pirelli chairman Marco Tronchetti Provera and Pirelli Tyre CEO Francesco Gori, at an event attended by Altero Matteoli, Minister for Infrastructure and Transportation, Adolfo Urso, Undersecretary for Economic Development and International Trade, Mario Valducci, chairman of the Transportation, Post and Telecommunications Commission of the Chamber of Deputies, and Andrea Mondello, Chairman of Unioncamere.