It all started with the initiation and acquisition  of several research projects which had the measurement, better understanding and lastly control of diesel particles as target. Over the years this very successful consortium has gained invaluable knowledge on all technical aspects of this topic. Especially applicability of exhaust treatment, engine improvement, and maintenance or ventilation management has been in the focus, always under the specific aspects of underground mining.

Every year in fall a several days conference is performed, up to now always in Toronto, Ontario, as the initiative to this model-project came mainly from mining in that region.

This year the conference again had 100+ participants from Canada and the US, but also from abroad. A short report by a participant is meant to the news about this very valuable international meeting.

MDEC 2010 started with a pre-conference field trip to a US-engine manufacturer “across the border”, which was followed by a day of workshops on modern clean engine technology and the use of biodiesel fuel.

The conference itself was initiated with a keynote address by Dirk Dahmann, IGF BG RCI, member of ISSA Mining, who gave an overview about current developments on a more international scale. Beside the particulates (“soot”) also gaseous components of diesel exhaust like nitrogen oxides will draw attention in future because of their possible health effects.

Section 1 then dealt with health effects. The speakers refreshed the current knowledge and cross referenced particle effects of diesel soot with modern developments in the fields of ultrafine particles (“nano-particles”). Though during the last years lung cancer used to be the main endpoint causing concern when exposure towards diesel exhaust was regarded, the possible cardiovascular effects do need attention as well.

Session 2 dealt with a specific topic, where MDEC was able to generate invaluable experience for the mining industry: field-testing of diesel exhaust aftertreatment devices. MDEC has always looked beyond the pure test stand investigation of the respective systems, as underground mining conditions tend to be much more demanding and “rough” compared to what surface use has to experience. Joe Stachulak of Vale, Sudbury, gave an impressive presentation on the successful application of a modern exhaust treatment system (Mann & Hummel), which was not only able to reduce particles but did also do this by NOT increasing the nitrogen dioxide concentrations in the exhaust. This exhaust-component is indeed generally seen as quite relevant. Other successfully field-tested systems were presented as well (e.g. RYPOS HDPF), when the retrofitting of existing machines currently still is a major topic. In this respect, the report on the first successful application of SCR (i.e. “selective catalytic reduction”) systems in mining environments was especially interesting, as these systems claims to reduce the whole of the nitrogen oxides in the exhaust (not only nitrogen dioxide).

In session 3 alternative power supply for underground engines was discussed. A quite advanced hybrid-loader was presented as well as the possibilities of the widespread use of electric trucks and natural gas as fuel.

The second day of the conference again dealt with aftertreatment systems in session 4 a general overview on the use of non-platinum-metal catalysts, especially vanadium pentoxide was given and  comprehensive test of several diesel oxidation catalysts was reported. Particular attention was drawn by PURItec who also reported the successful test of their exhaust treatment system being able not only to reduce particles but also NO₂  and in addition to some extent also the complete nitrogen oxide content in the exhaust. DCL then gave a presentation on their “partial” particle filter systems.

In session 5 the role of ventilation and monitoring was discussed. Here especially an Australian proposal (MicroCAD Australia Pty Ltd) drew attention, where based on simple and reproducible engine loading conditions under field conditions, a direct reading system for particles was introduced, which allows for the monitoring of the conditions and maintenance requirements of individual engines. A similar proposal from Vale, Sudbury, was based on the gaseous exhaust components. Finally, a very ambitious project for planning and execution of a novel ventilation concept based on air quality measurements (“ventilation on demand”) was discussed.

In session 6 general aspects of emission reduction were discussed. Aleksandar Bugarski of NIOSH, USA, discussed the role of particle loading in the performance of particle filters (disposable and regenerable). A second presentation focused on the role of individual miners’ behavior in causing high or low exposure and finally light was shed on the possibilities of emission reduction by simply lowering the weight of cars and other vehicles.

The last half day of the conference was dedicated to an intense round table discussion on Emissions Reduction & Alternative Technologies and secondly on low-emission modern engines and alternative power. As was done in this years’ conference the results of that round table discussion shall be reviewed in MDEC 2011.

As a summary MDEC can be recommended for all those mining specialists, who are involved in the use of diesel equipment underground and who are concerned about the hazards caused by the exhaust for miners’ health. ISSA Mining was shortly presented at the conference and in future a cooperation shall be considered. Read more about this on this website: www.mdec.ca.

Dirk Dahmann, IGF - BG RCI