oa Innovative Solutions for Sulphur in Qatar

The estimated sulphur output from Qatar is around 4 Mtpa by 2012, primarily from gas processing operations(Sulphur magazine, March/April 2009). Shell is using novel technologies to utilize sulphur in various applications such as concrete (Shell Thiocrete*), asphalt (Shell Thiopave*) and fertilizers (Shell Thiogro*). The sulphur utilization programme in Qatar Shell Research and Technology Centre is part of a global research and development effort to develop Shell's sulphur concrete and sulphur modified asphalt technologies, with particular emphasis on the needs of the Gulf region. Shell's innovative sulphur concrete technology has the potential to take sulphur concrete from use in niche applications such as chemical flooring to more mainstream applications such as garden products, road construction products (e.g. pavers and traffic barriers) and marine products. This is because the relatively low cost of the modification technology allows sulphur concrete to be considered in applications previously covered only by Portland cement. The first field trial of sulphur concrete in Qatar is a 16 square metre area of sulphur concrete tiles in the Pearl GTL Worker's Village, Ras Laffan Industrial City, Qatar, laid in May 2008. Laboratory results showed that the bending strength of all the sulphur concrete mixtures was greater than the strength of the cement concrete. Moreover, the water absorption of the sulphur concrete tiles was lower than that of the cement concrete tiles. Shell's sulphur-modified asphalt is a technology developed by Shell Sulphur Solutions in 2003, enabling a portion of the bitumen in an asphalt mix to be replaced by modified sulphur, resulting in a pavement that has enhanced mechanical properties such as increased stiffness and significantly reduced permanent deformation. A trial two-lane section of roadway of asphalt mix containing sections of Shell Thiopave and conventional asphalt mixture was constructed in October 2007 at Pearl GTL Worker's Village. The results of the field monitoring study showed that the total road section (sulphur-modified asphalt and conventional mixture) was free of any moderate or major distresses. Industrial hygiene monitoring during laying operations showed that SO2 and H2S emissions remain below the maximum limits when the temperature is controlled than 1450C.The laboratory characterization showed that the sulphur-modified asphalt mixture exhibited better resistance to permanent deformation and higher stiffness than the conventional mixture.