a b s t r a c tConcretes with a high thermal energy storage capacity were fabricated by mixing microencapsulated phase change materials (MPCM) into Portland cement concrete (PCC) and geopolymer concrete (GPC). The effect of MPCM on thermal performance and compressive strength of PCC and GPC were investigated. It was found that the replacement of sand by MPCM resulted in lower thermal conductivity and higher thermal energy storage, while the specific heat capacity of concrete remained practically stable when the phase change material (PCM) was in the liquid or solid phase. Furthermore, the thermal conductivity of GPC as function of MPCM concentration was reduced at a higher rate than that of PCC. The power consumption needed to stabilize a simulated indoor temperature of 23°C was reduced after the addition of MPCM. GPC exhibited better energy saving properties than PCC at the same conditions. A significant loss in compressive strength was observed due to the addition of MPCM to concrete. However, the compressive strength still satisfies the mechanical European regulation (EN 206-1, compressive strength class C20/25) for concrete applications. Finally, MPCM-concrete provided a good thermal stability after subjecting the samples to 100 thermal cycles at high heating/cooling rates.

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The main purpose of this paper is to determine how the torrefaction influences the pelletability of birch (hardwood) and spruce (softwood). Woods were torrefied at two different temperatures (225 and 275 °C) for 30 min. Energy loss (EL) and weight loss (WL), higher heating value (HHV), moisture uptake, water activity (a w), and particle size distribution of raw and torrefied woods were determined to characterize the materials before pelleting and to see how torrefaction affects physical properties of wood. The impact of biomass type, temperature, and compacting pressure on pellet strength and compressibility of raw and torrefied wood was investigated using a single pellet press method. Pellets were produced at three different temperatures (60, 120, and 180 °C) and eight different compacting pressures (5, 10, 20, 40, 80, 160, 240, and 300 MPa). Torrefaction at 275 °C significantly increased the HHV of both types of wood, in contrast to torrefaction at 225 °C. Compressing pressure and pelleting temperature had a significant positive impact on the material compressibility and strength. The strongest pellets were produced from raw spruce (68.62 ± 1.69 N/mm) and birch torrefied at 275 °C (86.34 ± 3.33 N/mm). Compression strength and density of the pellets were strongly correlated following a power low trend (R 2 > 0.98). Torrefied material required higher force for pellet discharge because of the higher friction generated on the pellet surface–die area.

Farming of Atlantic salmon has grown rapidly from its start in the early 1970s until today, with production approaching two million tonnes. Sea cages are the dominant production system for the ongrowing stage of salmon farming. It represents an effective production system with lower investment and running costs than land-based systems. The development and improvement of the sea cage farming system has been one of the most important factors for the growth of the salmon farming industry. However, during recent years certain problems related to their placement in the open marine environment have proved highly challenging, increasing operating costs and impacting on industry public relations. The problems are mainly due to parasites, diseases and escape of fish. In this article, emerging technical solutions for solving those problems are described.

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