The aim of this study was to characterize two types of cellulosic fibers obtained from bleached wood pulp and unbleached recycled waste paper with different cellulose content(from 47.4 percent up to 82 percent),to com...The aim of this study was to characterize two types of cellulosic fibers obtained from bleached wood pulp and unbleached recycled waste paper with different cellulose content(from 47.4 percent up to 82 percent),to compare and to analyze the potential use of the recycled fibers for building application,such as plastering mortar.Changes in the chemical composition,cellulose crystallinity and degree of polymerization of the fibers were found.The recycled fibers of lower quality showed heterogeneity in the fiber sizes(width and length),and they had greater surface roughness in comparison to high purity wood pulp samples.The high purity fibers(cellulose content>80.0 percent)had greater crystallinity and more homogeneous and smooth surfaces than the recycled fibers.The presence of calcite and kaolinite in all of the recycled cellulosic fibers samples was confirmed,whereas only one wood pulp sample contained calcite.The influence of the chemical composition was reflected in the fiber density values.Changes in the chemical composition and cellulose structure of the fibers affected the specific surface area,porosity and thermo physical properties of the fibers.More favorable values of thermal conductivity were reached for the recycled fibers than for the wood pulp samples.Testing the suitability of the recycled fibers with inorganic impurities originating from the paper-making processes for their use as fillers in plastering mortars(0.5 wt.%fiber content of the total weight of the filler and binder)confirmed their application by achieving a compressive strength value of 28 day-cured fiber-cement mortar required by the standard as well as by measured more favorable value of capillary water absorption coefficient.展开更多
Waste pulp(WP)is a typical byproduct of paper industry,and Chemical-looping gasification(CLG)as a recently developed technology is highly suited to dispose high-volatile wastes like WP.In order to make a high-efficien...Waste pulp(WP)is a typical byproduct of paper industry,and Chemical-looping gasification(CLG)as a recently developed technology is highly suited to dispose high-volatile wastes like WP.In order to make a high-efficiency oxygen carrier(OC)for CLG of WP,the Ni-containing electroplating sludge(NES)was used as the matrix and NiO modification was performed to enhance the hydrogen production in CLG.These resulted in a potentially high-efficiency OC denoted as NNES.Testing CLG of WP was in a fixed-bed reactor at 850℃by adopting NNES as the OC,injecting 2.4 mL/g(WP)water,and keeping a mass ratio of 1.0 between OC to WP.It produced 1.73 Nm^(3)/kg syngas that has an LHV of 11.9 MJ/Nm^(3)and a H_(2)/CO ratio of 3.63.In 10 redox cycles,the syngas yield did not have obvious decrease,but a certain reduction in the activity of NNES was observed.Characterization of the spent NNES revealed that it is the Ni agglomeration and inert silicate generation which reduced the activity of NNES.展开更多
面对禁废令实施后,箱纸板行业日益缺少优质纤维原料的行业痛点问题,以食品加工废弃物槟榔果壳作为原料,系统性分析其作为纤维原料的应用潜力。当选择用烧碱法制浆(用碱量18%,N a2O计),保温1.5 h时,浆料得率都在40%以上,细浆得率最高达87...面对禁废令实施后,箱纸板行业日益缺少优质纤维原料的行业痛点问题,以食品加工废弃物槟榔果壳作为原料,系统性分析其作为纤维原料的应用潜力。当选择用烧碱法制浆(用碱量18%,N a2O计),保温1.5 h时,浆料得率都在40%以上,细浆得率最高达87.9%。电子显微镜观察到槟榔果壳在煮浆后杂细胞变少,纤维表面粗糙度增加;当槟榔果壳浆质量占比10%时,得到的包装纸强度最大:耐破指数1.97 k P a.m^(2)/g、抗张指数34.21 N.m/g、撕裂指数6.5 m N.m^(2)/g、耐折度12次,且实验数据表明槟榔果壳浆占比在20%以内时,配抄纸张物理性能均满足国家箱纸板标准。展开更多
基金by the Slovak Scientific Grant Agency VEGA[Grant Nos.1/0277/15 and 1/0222/19]the Project Institute of Clean Technologies for Mining and Utilization of Raw Materials for Energy Use[Grant No.LO1406].
文摘The aim of this study was to characterize two types of cellulosic fibers obtained from bleached wood pulp and unbleached recycled waste paper with different cellulose content(from 47.4 percent up to 82 percent),to compare and to analyze the potential use of the recycled fibers for building application,such as plastering mortar.Changes in the chemical composition,cellulose crystallinity and degree of polymerization of the fibers were found.The recycled fibers of lower quality showed heterogeneity in the fiber sizes(width and length),and they had greater surface roughness in comparison to high purity wood pulp samples.The high purity fibers(cellulose content>80.0 percent)had greater crystallinity and more homogeneous and smooth surfaces than the recycled fibers.The presence of calcite and kaolinite in all of the recycled cellulosic fibers samples was confirmed,whereas only one wood pulp sample contained calcite.The influence of the chemical composition was reflected in the fiber density values.Changes in the chemical composition and cellulose structure of the fibers affected the specific surface area,porosity and thermo physical properties of the fibers.More favorable values of thermal conductivity were reached for the recycled fibers than for the wood pulp samples.Testing the suitability of the recycled fibers with inorganic impurities originating from the paper-making processes for their use as fillers in plastering mortars(0.5 wt.%fiber content of the total weight of the filler and binder)confirmed their application by achieving a compressive strength value of 28 day-cured fiber-cement mortar required by the standard as well as by measured more favorable value of capillary water absorption coefficient.
基金supported by the Key-Area Research and Development Program of GuangDong Province[2020B1111380001]Guangdong Basic and Applied Basic Research Foundation[2021B1515020068].
文摘Waste pulp(WP)is a typical byproduct of paper industry,and Chemical-looping gasification(CLG)as a recently developed technology is highly suited to dispose high-volatile wastes like WP.In order to make a high-efficiency oxygen carrier(OC)for CLG of WP,the Ni-containing electroplating sludge(NES)was used as the matrix and NiO modification was performed to enhance the hydrogen production in CLG.These resulted in a potentially high-efficiency OC denoted as NNES.Testing CLG of WP was in a fixed-bed reactor at 850℃by adopting NNES as the OC,injecting 2.4 mL/g(WP)water,and keeping a mass ratio of 1.0 between OC to WP.It produced 1.73 Nm^(3)/kg syngas that has an LHV of 11.9 MJ/Nm^(3)and a H_(2)/CO ratio of 3.63.In 10 redox cycles,the syngas yield did not have obvious decrease,but a certain reduction in the activity of NNES was observed.Characterization of the spent NNES revealed that it is the Ni agglomeration and inert silicate generation which reduced the activity of NNES.
文摘面对禁废令实施后,箱纸板行业日益缺少优质纤维原料的行业痛点问题,以食品加工废弃物槟榔果壳作为原料,系统性分析其作为纤维原料的应用潜力。当选择用烧碱法制浆(用碱量18%,N a2O计),保温1.5 h时,浆料得率都在40%以上,细浆得率最高达87.9%。电子显微镜观察到槟榔果壳在煮浆后杂细胞变少,纤维表面粗糙度增加;当槟榔果壳浆质量占比10%时,得到的包装纸强度最大:耐破指数1.97 k P a.m^(2)/g、抗张指数34.21 N.m/g、撕裂指数6.5 m N.m^(2)/g、耐折度12次,且实验数据表明槟榔果壳浆占比在20%以内时,配抄纸张物理性能均满足国家箱纸板标准。
