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Much research has been focused on maintaining stable humidity conditions in buildings housing heritage collections while reducing energy use. Moisture buffering by collections themselves can have a marked effect on the stabilisation of relative humidity (RH), the key parameter for preservation. Modelling of moisture transport using COMSOL Multiphysics was applied to transform three-dimensional paper and wooden objects into their one-dimensional representations, without changing the moisture uptake and release characteristics. The results were coupled to the modelling of indoor microclimate and energy consumption in collection storage spaces with the use of WUFI ® Plus software. The study revealed the crucial impact of air exchange rate of the building on the stability of indoor RH and the humidification and dehumidification loads required to maintain it. In the adequately air-tight library store, a sizeable paper collection was found to reduce the RH fluctuations from ±9% to ±6% around the yearly average and the energy consumption due to the humidification and dehumidification load by 38% when compared with the empty space, for a high-quality climate control scenario. In turn, a wooden collection, occupying a realistic fraction of a museum store was not large enough to significantly narrow down the RH variations and reduce the energy consumption. [ABSTRACT FROM AUTHOR]

Abstract: Wheat straw has been used as a pulping resource in China for many years. Wheat straw pulp (WSP) was widely used to substitute high quality chemical pulps such as those made from wood in producing writing and printing paper to reduce production cost of the resultant paper products and to improve paper smoothness without sacrificing paper strength. In this study, the process of co-refining of WSP and bleached hardwood kraft pulp (BHKP) was compared with the traditional separate refining and then blending these two pulps. The differences in refining energy consumption, the resultant pulp morphological and drainage properties, as well as the mechanical properties of the paper handsheets made of the resultant pulps were examined to explore the potential advantages of the co-refining process. The results show that the co-refining process has the potential to reduce refining energy consumption by at least 30% without affecting handsheet tensile and tear strength at a slightly lower re-wet tensile strength. [Copyright &y& Elsevier]

Abstract: The need for more rational use of water also calls for more efficient usage. An example is the production of tissue paper, where large amounts of water are discharged into the drain because its turbidity does not allow for recirculation. While this is a serious problem, even worse is the fact that the quality of such wastewater makes it difficult not only to recirculate but also to discharge due to environmental law restrictions. In this paper, electrocoagulation is proposed as a suitable technology to meet standards of water discharge, and even better, as a treatment option for removal of turbidity. Since energy consumption has been a drawback for EC applications, relevant aspects that contribute to increase it such as cell voltage and current density have been reviewed. For this purpose a systematic micro-electrolysis study combined with macro-electrolysis experiments have provided evidence that shows it is possible to achieve a turbidity removal of 92% with an energy consumption of 0.68kWh/m3. Thus, the results presented in this paper support the use of EC to obtain water of acceptable quality for reuse in the tissue paper industry. [Copyright &y& Elsevier]

• Hydropulping and selective dissolution/precipitation separate Tetrapak® constituents. • Effective separation of paper, AL and LDPE is achieved. • LDPE from inner layers exhibits properties comparable to virgin LDPE grades. Tetra Pak cartons, i.e. multilayer packaging consisting of paper, low density polyethylene (LDPE) and aluminium, are widely used as aseptic packages in the food and beverage industry. Paper can be easily recovered from this type of post-consumer beverage cartons (PCBCs) by the pulp industry. The remaining LDPE/aluminium by-product, however, cannot be easily separated to its constituents so currently it is mostly downcycled or used for energy recovery. The aim of this work is to develop an effective process that separates and recovers LDPE and aluminium of high purity and good quality from Tetra Pak cartons. To this purpose, following paper recovery by hydropulping, LDPE and aluminium are separated using a selective dissolution-precipitation (SDP) process. The recovered LDPE is characterized by FTIR spectroscopy, thermogravimetric analysis (TGA), differential scanning (DSC) and melt flow rate (MFR) measurements. The findings reveal that the SDP separation process is an effective method to recover LDPE and aluminium from PCBCs. [ABSTRACT FROM AUTHOR]