Volume 16 Issue 1

Fine paper mill sludge (FPMS) disposal has emerged as a problem since the dumping of FPMS was banned. This study investigated the effects of adding a refined recovered lubricating oil (ion-refined oil) to FPMS pellets to increase its heating value and combustion time and decrease ash content and ignition time. Fuel pellets were prepared in three conditions, C-1, C-2, and C-3. In C-1, ion-refined oil was added to FPMS to examine its burning capability. In C-2, two types of pellets were produced mixing sawdust and FPMS ratios of 25:75 and 50:50. A ratio of 50:50 was selected for C-3, to which the ion-refined oil was added in different ratios. The quality of the energy fuel pellets was determined using proximate and ultimate analyses, except for chlorine content, which was determined through liquid ion chromatography. The properties of fuel pellets were determined and compared with national standards. It was confirmed that the results for pellets at a ratio of 50:50 with 10% and 15% ion-refined oil were acceptable, because these results were comparatively similar to the standards. Finally, it was concluded that ion-refined oil was an effective additive to FPMS to increase the heating value for energy demand and lower the ash content.

For thermal comfort and energy-saving performance, a floor-heating method is superior to conventional heating modes, e.g., radiator, fan coil, etc. The floor-heating method has been developed to be a primary indoor heating form. Wood is the most common floor surface material. Due to the anisotropy of wood, it is difficult to obtain a general theoretical formula for its thermal physical properties. In this paper, intelligent algorithms were adopted to predict thermal conductivities of wood. First, the study elaborated frequently used testing methods of thermal conductivity. Next, 130 types of common wood species were measured to form a database of thermal properties. With this database, intelligent algorithms were used to make predictions. For the thermal conductivity predictions that were conducted with support vector machine, the degree of fit between the predicted results and the measured results was not less than 0.87 (k-fold validation). This study validated the feasibility of the usage of the intelligent algorithm for the research and prediction of the thermal conductivities of wood.

Various information systems have been implemented in most of the customized panel furniture companies in China, resulting in increased production difficulty and informational isolation. Enterprises need to adopt more systematic, scientific, and information-based methods to guide the production on the shop floor. Packaging optimization is important because it promotes sustainable development in furniture enterprise. Through the examination of the packaging process in customized panel furniture companies, this study investigated the bottleneck problems of the packaging process, which are predominantly focused on the calculation of the optimal packaging scheme and the upgrade of information systems. After exploring the theories and methods to solve the existing bottleneck problems, the heuristic algorithm was applied to obtain the optimal packaging schemes and complete the upgrade of packaging process information system. Based on the intelligent packaging software in company A, the Taguchi method was applied to find the best optimization parameters, which was proven effective in comparison with the original packaging solution. The number of packaging was decreased by 3.0%, and the amount of packaging corrugated paper decreased by 12.4. The packaging efficiency represented by the total packaging time showed a significant improvement despite the unit packaging time having increased by 2.0%.

This study was conducted on crude enzyme from the novel strain Acanthophysium sp. KMF001 using a mediator (surfactant). The surfactant was applied to the steam-exploded pretreated domestic wood biomass, and response surface methodology (RSM) was conducted to determine the optimum conditions for saccharification using the optimum substrate concentration, enzyme concentration, and surfactant concentration. Steam-explosion of Korean oak (25 kgf/cm2) for 7 min showed a maximum-predicted saccharification of approximately 99.9% at 7.0% substrate concentration, 37.5 FPU (filter paper units) enzyme concentration, and 475.8 mg/g-glucan surfactant (polysorbate 80) concentration. Steam-explosion of red pine (25 kgf/cm2) for 7 min revealed a maximum prediction saccharification rate of approximately 58.7% at 6.5% substrate concentration, 36.3 FPU enzyme concentration, and 330.3 mg/g-glucan surfactant (polysorbate 80) concentration. The extents of saccharification of Korean oak (99.9%) and pine (58.7%) demonstrated the high applicability of the crude enzyme from Acanthophysium sp. KMF001.

The aim of this work was to develop sustainable composites based on natural rubber (NR) and tea waste (TW) composites. The main concern was the compatibility mismatch between NR and TW. The presence of polar groups in the TW contributes to the weak interaction between relatively hydrophobic NR and TW. Therefore, silane coupling agent was introduced to enhance the properties of the composites. Treating the TW by silane coupling agent greatly influenced the overall properties of the composites. It speeded up the curing process due to its ability to reduce possible adsorption of accelerator by TW. Better interaction between TW and rubber matrix was clearly observed as evidenced by the maximum torque (MH) and tensile properties of the composites. Such findings can be verified by the Qf/Qg values, indicating better rubber-filler interaction when silane was used. Moreover, scanning electron microscope (SEM) images also provided some evidence related to the tensile properties observed. It can be concluded that the new composite based on NR and TW was successfully prepared with the contribution of a silane coupling agent.

Salix holocellulose liquefaction products (SHLP) were prepared by liquefaction of the wood. A spinning solution of polyurethane (PU) and SHLP was prepared, and microspheres were obtained by electrospinning. The bonding of SHLP and PU-SHLP was characterized via FTIR. The conductivity and viscosity of spinning solution were characterized by conductivity meter and viscosity meter, respectively. The electrospun fiber morphologies were characterized by SEM. The results showed that PU was introduced into SHLP. The concentration of solution was the main factor that affected the morphology of microspheres, and the diameters of microspheres was from 0.18 to 1.18 μm. In addition, in this electrospinning system, the concentration of liquefied products in the mixed spinning solution was the major factor that affected the morphology of microfibers, and the diameters of microfibers were from 0.29 to 1.78 μm.

An absorbent hydrogel with high-permeable solution resistance was prepared by free radical polymerization and crosslinking, by the process of micro/nano cellulose grafting with acrylic acid (AA) and 2-acrylamide-2-methyl propyl sulfonic acid (AMPS). Imbibition swelling curves revealed that absorbency of the hydrogel reached 70.2, 483.9, and 436.7 g/g in 0.9 wt% sodium chloride solution, 3 wt% urea solution, and rainwater, respectively. Fourier transform infrared results confirmed that acrylic acid (AA) and 2-acrylamide-2-methyl propyl sulfonic acid (AMPS) were grafted onto the micro/nano cellulose surface and the fiber structure persisted. Analysis with a confocal laser scanning microscope showed many pores on the polymer’s surface. Roughness became larger after grafting, which was conducive to water absorption capacity. Scanning electron microscopy (SEM) results showed that the main morphology of micro/nano cellulose did not change. BET results showed the presence of mesopores and macropores, which made the absorbent hydrogel highly permeable, allowing the internal and external absorbent groups to absorb water. H NMR confirmed that the cellulose was grafted with water-absorbent groups. In addition, lamellar structure and porous network morphology showed graft reaction occurred on the surface of micro/nano cellulose. The hydrogel has potential for agriculture and forestry, including in desertified and self-irrigated areas.

Liquid water and water vapor absorption on each separate surface and all surfaces at once, as well as the oven-dry shrinkage before and after the hot-water extraction of the wood, were examined using Korean Standards. The extractives content was examined using American Society for Testing and Materials (ASTM) standards. The highest water absorption and moisture adsorption were found in the transverse sections of both unextracted and extracted wood samples. There was no change in the equilibrium moisture content (EMC) in the unextracted vs. extracted wood samples at a relative humidity (RH) of 75%. However, the EMC in the extracted sample was higher than that in the unextracted sample at a RH of 90%. Swelling per 1% moisture content remained unchanged in the radial direction before and after extraction, while it increased in the tangential direction. The linear and volumetric shrinkage, as well as the coefficient of anisotropy, considerably increased after extraction. There was no difference in the extractive content between sapwood and heartwood. In conclusion, it was confirmed that the extractives in wood considerably affect the hygroscopicity and shrinkage of Paulownia wood.

Effects were assessed for the post-culture liquid medium originating from the cultivation of microorganisms that are present in the ecosystem called symbiotic consortium bacteria and yeast (SCOBY). The effectiveness of protecting Scotch pine wood samples against decomposition caused by the fungus Coniophora puteana was evaluated. The obtained results confirmed that impregnation of wood with post-culture medium reduces the possibility of decomposition of this wood by the test fungus. The potential biocidal effect of the post-culture medium from SCOBY was attributed to the presence the substances of a potential fungicidal nature, which were synthesized in the culture medium during metabolic processes occurring in the culture. The obtained results encourage further studies on the potential use of metabolites obtained from SCOBY breeding to protect wood against biodegradation.

Flax-based activated porous carbon materials (APCs) were prepared via KOH and urea synergistic activation in the carbonization process using flax pulp as a biocompatible and eco-friendly biomass precursor. A refining process was used to pretreat the flax pulp fibers, which has been known to improve and optimize the performance of APCs. The morphological and physicochemical structures of APCs were investigated, and the results showed that APCs exhibited high specific surface area and porous microstructure. Furthermore, APCs were rationally designed as a sustainable electrode material. The APC prepared by 60 °SR (Shopper-Riegler beating degree) flax pulp, named APC-60, exhibited the highest specific capacitance of 265.8 F/g at a current density of 0.5 A/g. The specific capacitance retention at 59% remained for the APC-60 electrodes at a high current density of 10 A/g. These results suggested that the flax-based APCs could be a promising carbon-based electrode material for sustainable electrochemical energy storage.