Background Emissions of volatile organic compounds (VOCs) and related odour problems are an important environmental problem. VOCs present a specific health and safety issue in affected workplaces as well as both a nuisance and a health-risk factor in the surrounding communities. Mechanical and semi-mechanical pulp production is a notable source of VOC emissions. According to the European Commission “Reference Document,” about 1 kg are emitted per tonne of pulp with the main sources being the evacuation of air from wood-chip washing and the condensation of steam contaminated with volatile wood components. Furthermore, pulping process conditions are characterised by fumes with high humidity, varying VOC concentrations, low oxygen content, possible sulphur compounds and large air-flows. The industry therefore presents particular challenges. There are several technologies that are currently used to achieve VOC abatement in different contexts. These show a wide range of approaches from end-of-the pipe to clean-technology solutions. However, one problem with this reality is that solutions cannot be compared easily and regulatory requirements differ greatly regarding specific applications. Objectives The VOCless pulping project aims to integrate the best components of existing VOC-abatement technologies into one integrated process for control and monitoring of VOC generation in the mechanical and semi-mechanical pulp production industry. The project planned to take an approach focused on end-of-pipe technology, since the source of the VOCs from the pulping process is natural. It sought to demonstrate the economic and technical viability of an abatement system that would reduce the volume of VOC emissions in typical mechanical and semi-mechanical pulp production by 90-95 % as well as effectively eliminating the odour problem. The difficult conditions in the industry were to be overcome by developing a “hybrid VOC abatement system”, possibly involving several technologies, including pre-filtering, VOC incinerator, bio-filter and condensation. The performance of the hybrid would be optimised through experimentation and the integration of special features to increase its reliability and efficiency and allow self-control and monitoring. Results The VOCless pulping project developed two technologies - one catalytic and one biological - to abate volatile organic compounds (VOCs) from mechanical pulping processes. It demonstrated that abatement rates of around 90% of VOCs are possible and that emission densities of VOCs could thus be reduced to 20-40 mg C/m3, much below the current general limits of 50 mg C/m3. The project worked initially to clarify the problem being faced. The taxonomy of mechanical, thermo-mechanical and chemico-thermo-mechanical pulping processes and their respective VOC emissions were investigated through measurements and literature survey. Current emission-abatement techniques were studied and the needs of the integrated system specified. Measurement of VOC emissions was a demanding task due to the large number of exhausts found from different stages of the pulping process. According to the project measurements, the specific airborne VOC emissions per tonne of pulp were around 0.03 kg in Italy and 0.41 kg in Finland. The type of wood used in pulping, whether from coniferous trees - Finland - or from broadleaf trees - Italy - seemed a more significant factor than the production process itself. At least the same amounts of VOC emissions were present in waste waters. Using the results of this investigation, two abatement processes were designed to tackle the VOC emissions. The first was based on an incinerator and the second on bio-technology. Specific features were developed for application in these processes, such as oxygen enrichment, automation, catalysts, bio-culture and pre-filtering. The team built the two pilot treatment systems in standard transportable containers. The catalytic system was tested in simulations at a plant in Finland, reaching a cleaning efficiency of 82-94 % and reducing VOC concentrations below 20 mg/m3. The bio-filter system was taken to Italy for testing, achieving a cleaning efficiency of 83 %. VOC concentrations in the clean gas after the bio-filter pilot plant were under 10 mgC/m3. The results allowed the design of a full-scale hybrid VOC-abatement system. The transferability and reproduction potential of this technology is high. Its widespread application would only involve marginal costs of 0.3-3.3 €/tonne of pulp - depending on the process - and could reduce total VOC emissions in Europe by about 6 000 tonnes. The technology could serve as a best-available-technology (BAT) guideline for developing stricter controls on VOC emissions. Further information on the project can be found in the project's layman report and After-LIFE Communication Plan (see "Read more" section).