木材干燥的国内外现状与发展趋势

阐述了常规蒸汽（热风）干燥、除湿（热泵）干燥、真空干燥、微波与高频干燥等各种木材干燥技术的国内外现状以及我国木材干燥技术与国际水平的差距；介绍了国内外木材干燥的理论研究动态；指出了今后木材干燥技术的发展趋势。     

木材微波干燥的应用与研究动态

分析了木材微波干燥的机理和优点，介绍了国内外木材微波干燥的研究与应用情况，指出木材微波干燥是一项具有广阔发展前景的新技术。建议今后加强木材微波干燥理论、干燥设备、干燥工艺、微波联合干燥技术等的研究工作。     

我国微波干燥技术应用研究进展

阐述了微波干燥技术的特点,对我国微波干燥技术在食品工业、材料化工、医药工业、矿产开采业、陶瓷工业、实验室分析、湿天然橡胶加工等方面的应用研究现状进行了综述：特别是对我国微波干燥技术在取代传统的燃烧柴油、燃烧煤、燃烧木材等方式为手段产生的热空气为介质,干燥湿天然橡胶的研究进展进行了详细阐述;同时对我国微波干燥技术的应用前景尤其在湿天然橡胶干燥加工中的应用前景进行了展望,并对我国微波干燥技术目前存在的问题及究方向作了预测分析。     

过热蒸汽干燥技术的研究进展

过热蒸汽干燥技术具有安全、节能、环保等诸多优点,越来越受到广泛关注。对过热蒸汽干燥技术进行了简介,分析了其优缺点。总结了过热蒸汽干燥的理论研究进展,并对过热蒸汽干燥技术在食品、木材、纸张、污泥和和褐煤等物料的应用现状进行了综合评述。总而言之,过热蒸汽干燥技术是一种先进的干燥技术,具有广阔的应用前景。     

《实用木材干燥技术》出版发行

《实用木材干燥技术》由我国木材干燥技术专家、北京林业大学张璧光教授主编，高建民、伊松林、周永东副主编。     

木材干燥基准的研究现状及展望

木材干燥基准是控制木材干燥过程中干燥介质的参数表。介绍了木材干燥基准的重要意义、类别、制定方法、研究现状等方面内容，指出了未来干燥基准的研究方向。     

2006年《干燥技术与设备》第4卷分类总目次

国外技术介绍日本干燥技术的最新进展李占勇,小林敬幸(1)专题综述木材干燥的国内外现状与发展趋势张璧光,谢拥群(1)我国木材干燥学术交流活动纪实朱政贤(2)第十四届国际干燥学术会议(IDS2004)简介曹崇文(3)中国干燥技术现状及发展趋势史勇春,柴本银(3)真空干燥设备的国内外发展动态徐成海,张世伟,赵雨霞,王喜鹏(4)固体干燥的物理解释和建模综述王维,陈国华(4)实用技术木材纤维板管道气流干燥系统的流体力学分析王旭(1)缓控释复合肥的包衣技术与设备邹龙贵(1)市场分析我国轻质碳酸钙应用的市场前景张春月,陈英军,韩恒朝(1)试验与研究真空油…     

移动式相变储热木材太阳能干燥装置的理论设计

针对木材太阳能干燥间歇性的不足以及传统太阳能储热采用混凝土、天然沸石等通过显热的方式储热体积大、热效率低的缺点,该文进行了移动式相变储热木材太阳能干燥装置的理论设计,并在此基础上完成了实际研制过程。该装置主要包括热管真空太阳能空气集热系统,石蜡相变储热系统,干燥系统,自动控制系统四个部分。该设计不仅能为相变储热式太阳能干燥装置的研制提供理论依据,更重要的是后续实验得出的规律可为进一步开展太阳能干燥技术的研究和工业化应用提供实验指导。     

改善干燥质量与木材加工其它环节对低碳经济的贡献

简述了森林吸收二氧化碳的碳汇作用,着重列举了在木材加工过程中,如木材干燥、制材、木材防腐及人造板加工中废旧木材的回收利用等各个环节,如何提高木材利用率,减少森林的砍伐量,以实现木材加工过程的低碳经济。如果干燥量为10万米。的木材,原来降等损失是10％,改进木材干燥的设备和干燥工艺使降等损失减少5％,砍伐量将减少1．25万米。,那就可以多吸收2．29×10^4吨的二氧化碳,同时多放出2．02×10^4吨的氧气;制材工序若出材率提高12％,每年可以减少原木砍伐量700万m^3左右,可增加碳汇量1281万吨,多放出氧气可供1512万人所需的氧气。同样,提高我国木材防腐处理的比例、加大人造板加工中废旧木材的回收利用比例,都可以明显减少森林的砍伐量,对低碳经济做出贡献。     

木材阻燃研究及发展趋势

近年,随着我国阻燃法规的建立健全,阻燃技术的不断发展,新型的木材阻燃剂及阻燃技术不断涌现。阐述了木材的化学组成及燃烧过程、木材阻燃剂类型、阻燃机理、木材阻燃处理方法及各种处理方法的优缺点,同时介绍了国内外木材阻燃研究的发展方向,对我国木材阻燃剂工业进一步发展提出了建议。木材阻燃的发展趋势是开发一剂多效的新型复合阻燃剂,同时深入探索阻燃机理,为组合新的阻燃体系提供有效的途径,使木材阻燃研究与市场实际需求相结合,为生产实践的应用提供了理论基础。     

High‐Pressure Treatment of Wood – Combination of Mechanical and Thermal Drying in the “I/D Process”

Thermal drying of materials with internal pores is always a time‐consuming and energy‐intensive step within a production process. For chemical and pharmaceutical mass products and, in particular, for wood as an important raw material it is desirable to reduce the water content before thermal treatment by mechanical operations. The wood‐processing industry, facing a rising stress of competition, is forced more than ever to offer high‐quality products at lowest prices. Today, drying of timber is mostly done by air drying or by technical drying in kiln dryers. In any case, drying is necessary to prevent deterioration in quality by shrinkage, formation of cracks, discoloration or infestation. A new process of dewatering wood by combining mechanical and thermal means has been developed at the University of Karlsruhe. Compared to conventional drying processes, short drying times and a low residual moisture content can be achieved and, thus, energy consumption and costs can be reduced. In industrial wood drying only thermal processes (e.g., convective kiln drying, vacuum drying, etc.) have been established because so far no method has been known for removing liquid by mechanical force without significant change in wood structure. With the new I/D process chances for alternatives to conventional thermal drying or for mechanothermal applications are offered.     

Recent Research and Development in Wood Drying Technologies in China

This article reviews research and application in applied wood drying technologies in China during the last two decades. It covers four areas including texts, manuals, and standards; predrying treatments; drying techniques and equipment; and energy conservation. The predrying treatments section includes presoaking, presteaming and preheating, end coating, and warp control. Drying techniques and equipment discussed involve predrying and redrying, conventional drying, high-temperature drying, vacuum drying, dehumidification drying, and press drying. The energy conservation section describes electricity conservation and heat conservation. Finally, some suggestions and remarks are given on the past experience and perspective for future research and development.     

Recent Research and Development in Wood Drying Technologies in China

This article reviews research and application in applied wood drying technologies in China during the last two decades. It covers four areas including texts, manuals, and standards; predrying treatments; drying techniques and equipment; and energy conservation. The predrying treatments section includes presoaking, presteaming and preheating, end coating, and warp control. Drying techniques and equipment discussed involve predrying and redrying, conventional drying, high-temperature drying, vacuum drying, dehumidification drying, and press drying. The energy conservation section describes electricity conservation and heat conservation. Finally, some suggestions and remarks are given on the past experience and perspective for future research and development.     

Canadian Developments in Kiln Drying

The objective of this paper is to summarize recent trends related to industrial kiln drying with especial emphasis on the drying of softwood dimension lumber in Canada. The paper explores future trends by analyzing the current market condition and wood products requirements. The paper also summarizes current research developments in the area of kiln lumber drying that was published by Canadian universities and research institutes. This includes basic research, such as wood physics and computer simulation, and applied research, such as non-conventional drying strategies and new technologies and sensors. A last note is also included to mention a kiln supervisor tool that was developed in Canada to analyze information related to kiln performance indicators. The kiln supervisor provides important trends for mills aiming to optimize their drying processes and realize gains without substantial investments in capital and other resources.     

Mathematical Modeling of Rotary Drying of Woody Biomass

Woody biomass in the form of forestry industry residues has been recognized as a promising resource for renewable energy and liquid fuels. Drying of the woody biomass is one of the key operations in development of the energy conversion technologies. Rotary drying is an effective method due to the enhanced contact between the solids and the drying medium (hot air). In this work, a mathematical model was developed to simulate the drying of the woody biomass as chips in a rotary dryer, based on energy and mass balance and transfer, experimental drying kinetics of the wood chips, and using literature correlations for the residence time. A new correlation between the theoretical maximum drying rate and the actual constant drying rate for the wood chips was obtained from the drying experiments, which was incorporated in the drying model. The model was applied both for cocurrent and countercurrent rotary dryers, and the simulation results are consistent with the observed trend. However, the accuracy of the model needs to be further investigated through experimental validation of the residence time correlation.     

褐煤干燥技术综述

褐煤在我国储量巨大,但由于褐煤含水量大,一直阻碍着褐煤的高效利用。本文介绍了褐煤干燥技术的概况,同时,重点介绍了适用于高含水褐煤的干燥技术。褐煤干燥技术对于我国清洁煤的利用是一个重要的研究领域,合适的褐煤干燥在煤化工行业有很好的前景。     

Color Changes of Birch Wood During High-Temperature Drying

In low-temperature drying, a high drying rate has been found to be adequate for silver birch (Betula pendula) and European white birch (B. pubescens) timber as far as wood colour is concerned. During high-temperature drying, however, birch timber darkens significantly if steam is used as the drying medium. The objective of this research was to study the effects of drying force (wet-bulb depression), timber thickness, and initial moisture content on the color of high-temperature-dried birch wood. The reflectance spectrum of wood was measured and transformed to the CIEL?a?b? color scale.

The increase in drying force increased the lightness and decreased the redness and the yellowness of wood. At the same time, the difference in color between the surface layer and the interior of boards increased. Increase in thickness and in initial moisture content increased the difference in color between the surface and the interior of boards. Pretreatment of timber with water soaking decreased the difference in color between the surface layer and the interior of boards when low drying force was used, but this difference was increased when high drying force was used.     

浅析热风干燥技术中的节能途径

阐述了我国碳排放现状及节能减排的紧迫感。以传统的热风炉粮食干燥的和传统的木材蒸汽干燥为例,分析了传统干燥热效率不高的主要因素,指出排气余热回收是传统干燥作业节能减排的主要途径之一,采用普通换热器、热泵及热管换热器回收排气余热,均有明显的节能效果。采用普通换热器平均节能12.4%,采用热泵平均节能40%左右,采用热管换热器居二者之间。介绍了太阳能干燥、太阳能与热泵组合干燥、热风与真空微波组合干燥、超声波与热风干燥组合等各种低碳干燥技术。建议逐渐推广用生物质能源作为干燥的热源,有利于实现低碳干燥。     

Mathematical Modeling of Kiln Drying of Softwood Timber: Model Development, Validation, and Practical Application

Mathematical modeling of wood drying is a powerful tool to better understand and quantify the effects of wood properties as well as the effects of drying and post-drying treatment conditions on drying and thus the wood drying models can be used to improve drying quality. The models that have been developed can be divided into three categories: models for drying a single board, models for drying a kiln-wide stack, and models for drying stress and deformation. The single-board drying model employs comprehensive heat and moisture mass transfer equations and can be used to investigate the influence of wood variability. The kiln-wide drying model, which is based on the transfer processes between wood and the drying medium, is able to examine the influence of drying schedules and wood properties. The stress model can predict stress development in drying and stress relief in final steam conditioning and post-kiln treatment. An integrated model can be used to optimize drying schedules and develop strategies for high-quality dried timber.