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1.
Environ Sci Pollut Res Int ; 30(32): 78793-78801, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37273053

RESUMO

The greenhouse gas (GHG) footprints of oriented strand boards (OSB) have been gaining growing concern. China is one of the largest manufacturers and traders of OSB in the world. However, little data are available concerning the GHG footprint of Chinese OSB production. The purpose of this study is to quantify and compare the GHG footprints of three types of OSB produced in China. Cradle-to-gate GHG footprints assessment models were built for OSB according to PAS 2050 guidelines. The results showed that the cradle-to-gate GHG footprints of OSB/2, OSB/3, and OSB/4 were 142.7 kg CO2 e/m3, 173.2 kg CO2 e/m3, and 374.2 kg CO2 e/m3, respectively. Raw material acquisition was the largest contributor to GHG footprint for three types of OSB (52.6~57.6%), followed by the production process of OSB (25.6~27.3%) and transportation (15.3~20.1%). The consumption of wood, MDI, electricity, and the transportation of wood were main emission hotspots in Chinese OSB production. Ultimately, four feasible GHG emission reduction measures were put forward from the perspective of reducing the usage of wood and MDI adhesive, decreasing the electricity consumption, and shortening the transport distance of wood.


Assuntos
Gases de Efeito Estufa , Gases de Efeito Estufa/análise , Pegada de Carbono , Dióxido de Carbono/análise , Madeira/química , China , Efeito Estufa
2.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(1): 55-9, 2016 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-27228740

RESUMO

The biomass to plastic ratio in wood plastic composites (WPCs) greatly affects the physical and mechanical properties and price. Fast and accurate evaluation of the biomass to plastic ratio is important for the further development of WPCs. Quantitative analysis of the WPC main composition currently relies primarily on thermo-analytical methods. However, these methods have some inherent disadvantages, including time-consuming, high analytical errors and sophisticated, which severely limits the applications of these techniques. Therefore, in this study, Fourier Transform Infrared (FTIR) spectroscopy in combination with partial least square (PLS) has been used for rapid prediction of bamboo and polypropylene (PP) content in bamboo/PP composites. The bamboo powders were used as filler after being dried at 105 degrees C for 24 h. PP was used as matrix materials, and some chemical regents were used as additives. Then 42 WPC samples with different ratios of bamboo and PP were prepared by the methods of extrusion. FTIR spectral data of 42 WPC samples were collected by means of KBr pellets technique. The model for bamboo and PP content prediction was developed by PLS-2 and full cross validation. Results of internal cross validation showed that the first derivative spectra in the range of 1 800-800 cm(-1) corrected by standard normal variate (SNV) yielded the optimal model. For both bamboo and PP calibration, the coefficients of determination (R2) were 0.955. The standard errors of calibration (SEC) were 1.872 for bamboo content and 1.848 for PP content, respectively. For both bamboo and PP validation, the R2 values were 0.950. The standard errors of cross validation (SECV) were 1.927 for bamboo content and 1.950 for PP content, respectively. And the ratios of performance to deviation (RPD) were 4.45 for both biomass and PP examinations. The results of external validation showed that the relative prediction deviations for both biomass and PP contents were lower than ± 6%. FTIR combined with PLS can be used for rapid and accurate determination of bamboo and PP content in bamboo/PP composites.

3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(6): 1546-50, 2015 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-26601364

RESUMO

The ratio of wood and plastic in Wood Plastic Composites (WPCss) influences quality and price, but traditional thermochemical methods cannot rapidly and accurately quantify the ratio of wood/PP in WPCss. This paper was addressed to investigate the feasibility of quantifying the wood flour content and plastic content in WPCss by Fourier Transform Infrared (FTIR) spectroscopy. With Chinese fir, polypropylene (PP) and other additives as raw materials, 13 WPCs samples with different wood flour contents, ranging from 9.8% to 61.5%, were prepared by modifying wood flour, mixing materials and extrusion pelletizing. The samples were analyzed by FTIR with the KBr pellets technique. The absorption peaks of WPCss at 1059, 1 033 and 1 740 cm(-1) are considered as characteristic of Chinese fir, and the absorption peaks at 1 377, 2 839 and 841 cm(-1) are typical of PP by comparing the spectra of WPCss with that of Chinese fir, PP and other additives. The relationship between the wood flour content, PP content in WPCss and their characteristic IR peaks height ratio was established. The results show that there is a strong linear correlation between the wood flour content in WPCss and I1 059/l 1 377/I1 033, /I1377, R2 are 0.992 and 0.993 respectively; there is a high linear correlation between the PP content in WPCss and I1 377/I1 740, I2 839 /I1 740 R2 are 0.985 and 0.981, respectively. Quantitative methods of the wood flour content and PP content in WPCss by FTIR were developed, the predictive equations of the wood flour content in WPCss are y = 53.297x-9. 107 and y = 55.922x-10.238, the predictive equations of the PP content in WPCss are y = 6.828 5x+5.403 6 and y = 8.719 7x+3.295 8. The results of the accuracy test and precision test show that the method has strong repeatability and high accuracy. The average prediction relative deviations of the wood flour content and PP content in WPCss are about 5%. The prediction accuracy has been improved remarkably, compared to thermochemical methods. More importantly, FTIR is more easy-handing. This experiment may provide a simple, rapid and accurate method for quantification of wood flour and PP in Chinese fir/PP composites.

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