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Sarpsborg, Norway

Zhang M.-H.,National University of Singapore | Reknes K.,Borregaard Ind. Ltd.
2nd International Conference on Sustainable Construction Materials and Technologies

This paper presents an experimental study on the effect of a newly developed modified lignosulphonate (PLS) superplasticizer on the workability retention and initial setting time of cement pastes in comparison to those of polycarboxylate (PCE) and naphthalene (SNF) superplasticizers. The workability retention was monitored by yield stress and effective viscosity of the pastes. The initial setting was determined by penetration depth in cement pastes. Different dosages of the superplasticizers were used to obtain cement pastes with yield stress < 6 Pa at 30 minutes at given water-to-cement ratios of 0.26 and 0.32. The results indicate that the paste with the PLS admixture had longer workable time and initial setting time than that with the PCE and SNF admixtures. Although the longer workable time is beneficial for hot weather concreting, the longer initial setting time of such material has to be taken into consideration where early strength development is essential. Source

Le Moigne N.,MINES ParisTech | Jardeby K.,Borregaard Ind. Ltd. | Navard P.,MINES ParisTech
Carbohydrate Polymers

Two dissolving sulphite wood pulps were treated by an enzymatic peeling protocol and the changes in terms of structure and alkaline solubility were analyzed. The enzymatic treatment leads to a fast and large decrease of degree of polymerization and of crystallinity, showing that the enzymes do not simply act on the fiber surface. The swelling and dissolution behaviour of the treated samples showed that the enzyme mixture used has two effects at short peeling times (i) a digestion of the primary wall which is seen by the near absence of ballooning and (ii) a destructive action on the inside of the fiber which is seen by the large decrease in the degree of polymerization. At long peeling times, the external walls are totally digested and the fiber structure is totally destroyed, as seen by the absence of birefringence. The alkaline solubility of the different treated samples was investigated in a NaOH 8%-water solution. As expected from thermodynamic considerations, there is a direct correlation between the solubility and the degree of polymerization. However, aside thermodynamics, the removal of the external walls and the macrostructural destructuration of the fibers are key factors in the improvement of the dissolution of wood cellulose fibers. At constant intrinsic viscosities of the cellulose materials, the alkaline solubility is almost two times higher when the external walls are removed. The macrostructural destructuration of fibers by enzymes allows a high degree of polymerization to be preserved while keeping a good alkaline solubility. © 2009 Elsevier Ltd. All rights reserved. Source

Blatny J.M.,Norwegian Defence Research Establishment FFI | Olsen J.S.,Norwegian Defence Research Establishment FFI | Andreassen O.,Norwegian Defence Research Establishment FFI | Waagen V.,Borregaard Ind. Ltd. | Reif B.A.P.,Norwegian Defence Research Establishment FFI
Proceedings of SPIE - The International Society for Optical Engineering

Two outbreaks of legionellosis occurred in the Sarpsborg/Fredrikstad region southeast of Norway in 2005 and 2008 where more than 60 exposed individuals were infected and 10 case patients died. The air scrubber at Borregaard, a wood-based chemical factory, was identified as the outbreak source. High concentration levels of Legionella species, including the etiological agent L. pneumophila SG1 was found in the aeration ponds, which belongs to Borregaard's biological treatment plant. Results showed that these ponds were able to generate Legionella-containing aerosols that were transported by the wind as such aerosols were measured up to 200 meters downwind of the pond. Our studies did not detect L. pneumophila SG1 isolates, only L. pneumophila SG4 during the air sampling measurement campaign. Furthermore, the operational conditions of the air scrubber proved to be harsh for Legionella growth as the outbreak L. pneumophila strains were not able to grow at 45°C and pH8 (conditions during the outbreaks). These results, together, lead us to suggest that the aeration pond should be regarded as the primary amplifier and disseminator of Legionella and L. pneumophila and thereby most likely being the outbreak source. © 2011 SPIE. Source

Moosavifar A.H.,Borregaard Ind. Ltd. | Sedin M.,Chalmers University of Technology | Theliander H.,Chalmers University of Technology
Nordic Pulp and Paper Research Journal

In this study, experimental results from earlier work on viscosity measurements of black liquors with different lignin contents were used to develop an empirical model describing viscosity as a function of temperature, dry content and concentration of lignin and hemicellulose. The liquors studied were taken from six different lignin extraction runs, according to the LignoBoost process, at different mills. The viscosity data was available at a wide range of temperature (40-130°C) and dry content (30-70 w/w-%): this data was used to calculate the parameters in the model. Furthermore, one of the general correlations was developed by taking the concentrations of lignin and hemicellulose into account. The results of this study showed that a much better fitting of the model could be obtained by taking the influence of the organic content in the black liquor into account. Source

Blatny J.M.,Norwegian Defence Research Establishment FFI | Fossum H.,Norwegian Defence Research Establishment FFI | Ho J.,Defence Research and Development Canada | Tutkun M.,Norwegian Defence Research Establishment FFI | And 5 more authors.
Frontiers in Bioscience - Elite

Legionella was detected in aeration ponds (biological treatment plant) at Borregaard Ind. Ltd., Norway, and in air samples harvested directly above these ponds. Since 2005, three outbreaks of legionellosis occurred within a 10 km radius from this plant. This work addresses the dispersion patterns of Legionella-containing particles by characterizing the aerosol plume emitted from these ponds (outbreak source) < 500 meters using windtunnel measurements, CFD simulations, and real-life measurements. The most abundant particles directly over the ponds were < 6 and >15 μm. The results showed that the aerosol plume remained narrow; 180 meters wide at 350 meters downwind of the ponds, and that 2 and 18 μm aerosols were mainly deposited in the vicinity of the ponds (150-200 meters). Furthermore, the maximum aerosol concentration level appeared 5-10 meters above ground level and the maximum concentration 500 meters downwind was approximately 2% of the concentration level directly above the ponds. Our study demonstrates the strength of combining modeling with real-life aerosol analyses increasing the understanding of dispersion of airborne (pathogenic) microorganisms. Source

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