Effects of White-Rot Fungi Composting on Wood Powder-Chicken Manure Mixture

[ Objective] To explore the possibility of treating livestock manure with white-rot fungi. [Method] The wood powder-chicken manure mixture was respectively composted by three kinds of white-rot fungi, the weight of lignin, cellulose, protein, fat, ash and crude polysaccharide as well as the mycelial growth was determined during this process. [ Result] The mixture was better composted with white-rot fungi than the control. The best effect was achieved in P. ostreatus composting group. In this group, the rate of weight reduction, lignin degradation and cellulose degradation were respectively 15.68% （6.79 times as great as that of the control group）, 39.92% （6.54 times as great as that of the control group） and 32.26% （2.77 times as great as that of the control group）. The weight of protein and fat were increased by 31.68% and 146.58%, respectively. The content of crude polysaccharide was 2.43%. No crude polysaccharide was detected, and the weight of protein and fat decreased by 21.96% and 70.99%, respectively. [ Conclusion] It is feasible to compost livestock and poultry manure with white-rot fungi.

Dynamic simulation and experimental study of the effect of one-dimensional vibration on the packing of wood powder particles

In the industry of production of high-density fiberboards without adhesive,applying vibration to the particle packing system before pressing and molding is an effective way to improve the uniformity of particle packing and reduce porosity.In this work,physical experiments combined with numerical simulations are used to systematically investigate the packing structure behavior of wood powder particles under different vibration conditions.Macroscopic and microscopic properties such as porosity,coordination number,radial distribution function,and contacts are characterized and analyzed.The results indicate that when the vibration frequency is 72 Hz and the vibration amplitude is 1 mm,the porosity of wood powder particles closely packed is minimized.The results of the Discrete Element Method show that the distribution of the coordination number is approximately normal.As the vibration conditions change,the packing structure becomes tighter,but the main peak of the radial distribution function becomes blurred or even disappears.Vibration does not significantly change the type of contact in the packing structure.The conclusions can provide more comprehensive vibration conditions and microscopic theories for the uniform spreading of wood powder particles before pressing,ensuring that the finished panels have excellent mechanical and physical properties.

Experimental Study of Influence of Fuel Ratio on Combustion Characteristics of Diesel-Wetted Wood Powder

In this study, experiments were conducted to examine the influence of the fuel ratio(i.e., the ratio of diesel mass to wood powder mass) on the combustion characteristics of diesel-wetted wood powder, in which 0# diesel and poplar wood powder were used and well mixed. The fuel ratios were set to 0, 0.5, 1.0, 1.5, and 2.0. Fire behaviors, temperature distributions, mass loss rates, and CO concentrations were measured and analyzed. The results showed that because of the coupled effect of evaporation and the capillary force, the ignition point of diesel-wetted wood powder(less than 3°C) dropped dramatically as compared with that of pure wood powder(higher than 280°C) and pure diesel(higher than 107°C). At the early stage of combustion, diesel is lifted upwards by the capillary force, increasing both the concentration of diesel vapor and the temperature at the surface. When the surface temperature reaches that of the pyrolysis of wood powder, considerable pyrolysis gas emerges and combusts. As the flammable gas is consumed gradually, carbon combusts prominently when plenty of oxygen diffuses to its surface. Regarding the influence of the fuel ratio, the results showed that in cases with lower fuel ratios, the combustion was not self-sustainable. When the fuel ratio was relatively high, the temperature at the flame center was lower owing to incomplete combustion. More CO could be found in cases with higher fuel ratios in the early and late stages of combustion. The results could help to improve knowledge regarding combustion of fuel-wetted wood powder.

Dynamic Mechanical Properties of Wood Powder /Polypropylene Composites

The dynamic mechanical properties of wood powder/polypropylene composites with different wood content treated and untreated with the compatibilizer have been studied. It has been found that addition of wood powders and the compatibilizer can both improve the viscoelasticity of composites. Glass transition temperature (Tg) of appropriate wood powder-filled composites decreased. The value for the storage modulus (G') increased gradually with increasing wood powder content. The addition of the compatibiliz...

Analysis on Volatiles Release Behavior of Poplar Wood Powder at Different Temperature by TD-GC/MS and Environmental Protection Evaluation

The volatiles release behavior of poplar powder has been studied by TD-GC/MS online technique at different temperatures.The results show that the proportion of main harmful components was higher than that of beneficial in the volatiles of poplar powder at 40℃ and 90℃,the harmful components was 1.7 times higher than beneficial components. The proportions of main beneficial and harmful components were equivalent at 60℃,while the main beneficial components was 5.42 times higher than that of harmful.Taking poplar wood powder as substrate to prepare wood powder-based composites by high-pressure no-gel molding compaction between the temperature of lignin softening point and wood materials carbonization(about 150-180℃) can present a satisfactory environmental friendliness.

Toughening wood/polypropylene composites with polyethylene octene elastomer (POE)

Polyethylene octene elastomer (POE) as impact modifier was incorporated into wood/polypropylene composites (WPC) to enhance the impact strength of the composite. Two extruding routes, i.e. direct extruding route and two-stage extruding route, were adopted to produce Wood Powder/PP/POE ternary composites. The mechanical and dynamic mechanical analysis (DMA) properties of the composites were investigated. The results showed that the addition of POE can increase the impact strength of the composites, and the composites produced via two-stage extruding route showed superior mechanical properties. The results of the DMA confirmed the mechanical tests.

Wood/Cu混合粉末温压成形致密化过程数值模拟

基于木粉和电解铜粉混合粉末(Wood/Cu粉末)的模压成形试验数据,借助有限元法分析成形压力对Wood/Cu压坯密度的影响,并通过理论计算与试验检测验证相结合的方法对成形压力与压坯密度的关系进行回归分析。结果表明,Shima模型特别适合于Wood/Cu混合粉末常温成形过程的数值模拟,模拟结果与试验结果一致;但在温压成形工艺条件下的模拟结果与试验结果存在明显偏差。通过理论计算、试验检测与分析修正获得的Wood/Cu粉末温压成形"压力-密度"模型由理论方程与修正项组成,对于金属化木质材料及其制品的开发具有实际指导意义。

Development and Evaluation of an All Weather-Type Solar Drying House to Make for Wood Pellet Material

To suppress the global environment pollutions, we tried to develop a new-type solar drying house by improving a typical agricultural green-house, so that an all weather-type solar drying house was invented ultimately. This house is capable to dry raw wood materials (Ogako) into suitable moisture content (Mc) to make a wood pellet. The all weather-type solar Ogako drying house is covered with a triple transparent film, and an open/close free-type shield sheet is spread along with house’s inner surface with a small space, which is opened when solar radiation is incident on the house in daytime and closed to prevent heat loss from the house while out of sun shining in night. Inside of the all weather-type solar Ogako drying house, there are four belt-conveyors over which four top radiation panels are hanged, and on which four Ogako agitators are touched, a turn-table, two hoppers, four small fans, and besides, a floor heating is molded in concrete floor. Also on the north wall outside the house, two insulated cylinders (chimney) are stood up vertically to exhaust inside moist air passively. Then, to make clearly the operation performance of the house, the drying tests for the proof examination were conducted nineteen times at first test site in Ashoro where is located east-central part of Hokkaido, Japan. As a result of the drying test for the proof examination, it was made clear that the all weather-type solar Ogako drying house is practically useful as a supplementary apparatus to produce the dried Ogako, and consequently to suppress CO2 exhaustion.

加工因素对HDPE基木塑复合材料静曲强度的影响

为了研究木塑复合材料加工因素对复合材料力学性能的影响,采用正交实验法以静曲强度为评价标准,利用极差分析和方差分析法分析了螺杆转速、造粒温度、偶联剂质量分数和木粉含量等加工因素对力学指标静曲强度影响的顺序及各因素的最佳水平,确定了木塑复合材料静曲强度的各加工因素的最佳参数组合;系统地分析了各加工参数对木塑复合材料力学性能指标静曲强度的影响。结果表明,影响木塑复合材料静曲强度的主要加工因素由大到小依次为偶联剂质量分数>木粉含量>转速>造粒温度;得到最佳静曲强度的加工因素参数组合为转速150 r/min、造粒温度145℃、偶联剂质量分数为5%、木粉含量为60%;木粉含量及偶联剂质量分数对材料的静曲强度具有显著性影响,转速和造粒温度对材料静曲强度影响的显著性较低,其中,随着偶联剂含量的增加,静曲强度呈明显上升的趋势;当木粉含量从30%增大至70%时,材料的静曲强度呈先增加后减小的趋势。

Chemical characterization of smoke from the production process of wood-plastic composites

The chemical composition of unpleasant smell, emitted from the production process of wood-plastic composites using Manchurian ash sawdust （Fraxinus mandschurica Rupr.） and polypropylene powder as the raw material, was investigated. Wood sawdust and polypropylene powder were subjected to heat treatment to 290℃ during 8 min （the conditions were similar to those employed on an industrial scale）. The emitted compounds were collected and analyzed by gas chromatography-mass spectrometry （GC-MS）. The analytical results showed that the unpleasant smell was emitted from the pyrogenation of wood sawdust rather than from the polypropylene powder. Nine types of compounds （hydrocarbons, ethers, phenols, aldehydes, ketones, alcohols, acids and their derivatives, furan and its derivatives, and nitrogen-containing compounds） were collected in the gas phase during heating. Among those 126 components detected by GC-MS, 112 compounds were identified.

高性能TEMPO功能化木粉-聚乙烯醇/锂铝水滑石复合材料的制备及性能

【目的】探究聚乙烯醇/锂铝水滑石(PVA/LDH)分散液对巴沙木加工剩余物理化性能的影响,为构建高性能木质复合材料提供理论依据,实现木材加工剩余物的高值化利用。【方法】受天然贝壳“砖-泥”有序结构启发,以巴沙木加工剩余物(木粉)为主要原料,经脱木素和氧化改性,获得2,2,6,6-四甲基哌啶-1-氧自由基(TEMPO)功能化改性木粉(T-WP),向其中加入不同比例PVA/LDH分散液,通过真空抽滤自组装过程将无机纳米片水滑石插层,构建天然有机聚合物与无机纳米片复合的高性能新型木质层状复合材料,基于FTIR、XPS、Zeta电位、力学性能等测试与分析,探究各组分间的相互作用及机械性能协同增强机制。【结果】1)木粉粒径100目时,纯T-WP薄膜的力学拉伸强度和韧性最大,分别为(225.25±0.82)MPa和(5.18±0.36)MJ·m^(-3)。2)PVA/LDH纳米片体系在T-WP上成功插层,并与T-WP分子链上的含氧官能团形成氢键、静电相互作用以及共价交联作用。3)对不同PVA/LDH添加量的T-WP-PVA/LDH复合材料进行力学性能分析,PVA/LDH添加量为20 wt%时,T-WP-PVA/LDH复合材料的拉伸强度和杨氏模量最大,分别为(287.29±4.91)MPa和(14.21±2.60)GPa,是纯T-WP的1.28和2.40倍。4)在相对湿度90%、温度25℃条件下放置16 h,T-WP-PVA/LDH复合材料的吸湿率为45.43%,力学拉伸强度为105.40 MPa;在湿润土壤中,T-WP-PVA/LDH复合材料表现出较好的可生物降解特性。【结论】T-WP-PVA/LDH仿生层状复合材料中,T-WP分子链上的活性含氧基团与PVA/LDH体系形成氢键、静电相互作用以及Al—O—C共价交联作用,构建协同增强体系,赋予T-WP-PVA/LDH复合材料优异的力学性能。木质层状复合材料优异的特性使其在包装、地膜、一次性餐盒等领域具有广泛应用前景,有望替代部分聚乙烯、聚丙烯等石油基产品。

光热材料-木材太阳能驱动界面蒸发器研究进展

【目的】通过研究太阳能驱动界面蒸发技术,更好地实现该技术在解决淡水资源短缺方面的应用。【进展】总结太阳能界面蒸发技术的工作原理、光热材料、蒸发器基体等;概括光热材料-木材蒸发器的结构设计;着重综述使用碳基材料、金属纳米材料、半导体、有机聚合物等光热材料结合木材的蒸发器的系列研究结果。【前景】认为太阳能界面蒸发器可以充分利用光能,是一种替代传统海水淡化获取清洁淡水的很有前途的方法;碳基材料、金属纳米材料、半导体和有机聚合物是常用的高效光热转换光热材料;利用木材本身的优异性能进行结构与功能设计,可以改善水传输效率低及耐久性差等不足;基于光热材料-木材的太阳能界面蒸发技术,为制备洁净水和解决淡水资源匮乏问题提供了新思路。建议不断研发新型光热转换材料,以获得高光热转换效率的多功能性木材基太阳能蒸发器,并降低材料的制备成本以及制备难度;进一步研究并明确传热和传质机制,控制木材的多孔网络以匹配水的相变和蒸汽扩散的速率;尝试将小木块组装成大木板蒸发器,以提高蒸发器的可扩展性。

牡蛎壳粉-木醋液促进市政污泥好氧发酵的腐殖化

为提高市政污泥传统好氧发酵产品的肥效,该文以市政污泥为原料、稻壳为辅料,通过添加物料总质量15%的牡蛎壳粉(OS组)、添加2%的木醋液(WV组)及联合添加15%的牡蛎壳粉+2%的木醋液(OS-WV组),探究牡蛎壳粉联合木醋液对市政污泥好氧发酵腐殖化进程及其产物肥效的影响。结果表明,OS-WV组可优化堆体理化性质并提高氮磷养分,发酵结束时,OS-WV组发酵产物的TN、NH_(4)^(+)-N、NO_(3)^(-)-N、TP、Olsen-P分别达到19.15、0.025、0.43、23.89、1.74 mg/g,显著高于其他实验组;OS-WV组堆体的腐殖化程度更高,胡敏素(HU)向胡敏酸(HA)和富里酸(FA)转化的强度更大。傅里叶红外光谱结果分析表明,联用牡蛎壳粉和木醋液可促使堆体中多糖类物质降解,增加芳构化程度,从而强化了腐殖化过程;三维荧光光谱分析表明,牡蛎壳粉和木醋液在促进生成高分子量和结构复杂的腐殖质(HS)组分方面具有协同作用;经过为期40 d的小白菜盆栽实验,验证了OS-WV组发酵产物的植物促生长效果最佳。15%牡蛎壳粉联合2%木醋液施用于市政污泥好氧发酵堆体,可促进堆体腐殖化进程并提高发酵产物的肥效。

多孔木材用高透抗塌陷聚氨酯涂料的制备及应用研究

为研制一种多孔木材用高透抗塌陷聚氨酯涂料,通过合成羟值为168 mgKOH/g的高羟值醇酸树脂,并搭配折光率与醇酸树脂相近的聚乙烯微蜡颗粒粉,再与TDI-TMP、TDI固化剂制备成聚氨酯涂料。探究了醇酸树脂羟值、氰羟比[n(—NCO)∶n(—OH)]对涂层抗塌陷性的影响,以及不同填充粉的选择和用量对涂层性能的影响。结果表明:随着羟值从105 mgKOH/g逐步提升到168 mgKOH/g,或氰羟比从0.6∶1递增到1.4∶1时,涂层的硬度和耐溶剂溶胀性程度均会递增。使用微蜡粉代替常规滑石粉和透明粉,提高了填充性且兼顾很好的光线穿透性。经检测和应用证明,该聚氨酯涂料成膜后涂层透明性好,常温干燥24 h无气味,2周基本不塌陷,干燥时间短,具有颗粒效果。该涂料填充性好、通透性高,可以应用于非洲多孔木材中,提高非洲木材的使用率和满足质量要求。

相容剂对聚丙烯/木粉复合材料的影响

利用相容剂对聚丙烯(PP)/木粉进行改性研究,结果表明,加入相容剂后,PP和木粉的界面相容性得到改善,颗粒引起的应力集中和产生缺陷的几率大大降低,复合材料的弯曲强度、拉伸强度、断裂伸长率、硬度、维卡软化温度、加工流动性能和冲击强度均有不同程度的提高。综合复合材料的物理性能,相容剂用量在10份左右最佳。

POE-g-MAH在木粉/PVC复合材料中的应用研究

在木粉/PVC共混体系中,POE-g-MAH的加入提高了复合材料的拉伸、冲击强度,改善了材料的外观及加工性能。通过SEM发现,POE-g-MAH的引入增强了木粉和PVC之间的界面黏接性。而CPE的加入与POE-g-MAH共同作用,进一步改善了体系的机械性能、加工性及外观。

木粉填充聚乙烯复合材料的研究

采用木粉对聚乙烯 (PE)进行改性 ,研究了树脂牌号、引发剂、接枝单体对相容剂性能的影响以及木粉的粒径、水含量及相容剂用量等因素对聚乙烯 /木粉复合材料性能的影响 ,通过SEM (扫描电镜 )对材料结构进行了表征。结果表明 :复合材料的弯曲性能随木粉用量的增加而大幅度提高 ,耐热性能也有明显改善 ,而冲击性能则迅速下降 ;木粉的粒径对复合材料弯曲性能的改善不大 ,木粉水含量对复合材料的弯曲性能则有较大影响 ;相容剂用量在10 %以上 ,可提高复合材料的弯曲性能 ,对冲击性能影响不大。

聚乳酸/木粉复合材料的结构与性能研究

以聚乳酸和杨木粉为原料制备了聚乳酸/木粉复合材料,研究了木粉处理、木粉用量对复合材料性能的影响,并对复合材料形态结构进行了观察。结果表明,与未处理木粉相比,木粉表面偶联处理使复合材料力学强度略有下降,碱处理对复合材料力学强度的提高并不明显。随木粉用量增加,复合材料的拉伸强度和弯曲强度分别在木粉质量分数为40%和20%时达到最高值,比纯聚乳酸的强度分别高出41.8%和38.6%。复合材料为假塑性流体,随木粉用量增加,剪切黏度增加。光学显微镜观察发现,未处理木粉能够均匀分散在聚乳酸基体中。

柱塞式压块机压块成形理论分析与试验研究

对锯末、秸秆等物料的压块成形原理进行了探讨与分析，研究了压模筒内物料所受轴向压应力与径向压应力之间的关系及其沿压模筒长度的分布；还推出了活动压模筒的柱塞压力与压模筒夹紧力之间的关系。本文用锯末进行了压块试验研究，得出了压块机功率、柱塞压力与饼块密度的回归关系，还验证了活动压模筒的柱塞压力与压模筒夹紧力之间的关系。

木粉对缓释化肥包膜透过能力的调控

采用48μm和150μm木粉为填料制备了聚苯乙烯/木粉复合膜,考察了木粉含量、复合膜厚、木粉粒径对复合膜透过性能的影响。结果表明,木粉可以很有效地调控聚苯乙烯膜对尿素的透过能力,复合膜对尿素的透过速度明显大于纯聚苯乙烯膜的透过速度;随着木粉含量的增加,复合膜对尿素的透过速度增加。光学显微镜观察发现,木粉中纤维状结构明显,复合膜在水中浸泡后其中木粉吸水溶胀,成为复合膜中尿素透过快速通道。