Effects of Different Flue-curing Barns on Aroma Quality of Upper Flue-cured Tobacco Leaves of K326

[Objective] This study was conducted to compare the aroma quality of up-per leaves of K326 flue-cured in different barns, and provide theoretical references for the development and optimization of bulk curing barn and the supporting tech-niques. [Method] The upper leaves of K326 were flue-cured in a commonness barn, a four-shelf bulk curing barn and a three-shelf bulk curing barn separately, and then the contents of aroma components and taste quality indices of the finished leaves were measured and compared. [Result] The contents of total aroma components, chromoplast pigment degradation products, phenylalanine aroma components and neophytadiene showed no significant differences in the leaves flue-cured in four-shelf bulk curing barn and commonness barn, but were significantly or very significantly higher than those in the leaves flue-cured in three-shelf bulk curing barn. The con-tents of carotenoid degradation products, Mail ard reaction products, cembranes aro-ma components and total aroma components （except neophytadiene） showed no significant difference among the three treatments. The results of sensory evaluation revealed that the sensory taste of the leaves flue-cured in four-shelf bulk curing barn was the best, as the finished leaves had rich, delicate aroma, comfortable and clean aftertaste. The leaves flue-cured in commonness barn was better than those flue-cured in three-shelf bulk curing barn in aroma quality, amount and aftertaste. [Conclusion] The four-shelf bulk curing barn had a large volume for tobacco leaf processing, but a similar baking environment to the commonness barn, which is conducive to the formation and accumulation of aroma components, so the finished leaves had similar appearance and quality with those flue-cured in commonness barn. The upper flue-cured leaves in three-shelf bulk curing bran had poorer quality than those flue-cured in the other two barns.

Application of Polyurethane Curing Barn in Flue-cured Tobacco Production

[ Objective] This study aimed to investigate the curing performance of polyurethane curing barn and reduce the cost of tobacco leaf flue-curing. [ Meth- odl The temperature control effect, curing effect and curing cost of polyurethane curing barn and traditional bulk curing barn were analyzed and compared. [ Re- suit] The results showed that there were no significant differences in curing performance between two types of curing barns. Horizontal temperature differences in- creased slightly as the temperature rose. Specifically, horizontal temperature differences between each layer ranged from 0.2 ~C to 0.5 ~. Both two types of curing barns exhibited uniform air distribution. Polyurethane curing barn exhibited stable vertical temperature differences. Both two types of curing barns presented good curing effects with slight differences. Polyurethane curing barn exhibited higher economic benefits, lower coal cost, lower electricity cost, lower labor cost and lon- ger service life than traditional bulk curing barn, but its construction cost was higher. [ Conclusion] Polyurethane curing barn exhibits better curing performance with ~ood application prospects.

Study on Curing Effect and the Waste Heat Recovering Equipment Design of Flue Gas of Bulk Curing Barn

In order to realize tobacco curing with energy saving and emission reduc- ing and lower cost, the waste heat recovering equipment was designed and built on blowing-upward type bulk curing barn. The comparative experiment of tobacco leaf curing was conducted between a bulk curing barn with waste heat of flue gas and conventional bulk curing barn. The results showed that the effect of saving coal in bulk curing barn with waste heat of flue gas was obvious than the contrast. The coal consumption quantity was 1.531 kg per kg of dry tobacco leaf. The saving coal in bulk curing barn with use waste heat of flue gas was 0.181 kg per kg of dry tobacco leaf than the contrast and saving coal rate was 10.57%. The electricity consumption quantity was 0.593 kWh per kg of dry tobacco leaf. The saving elec- tricity quantity in bulk curing barn with use waste heat of flue gas was 0.022 kWh/kg and the saving electricity rate was 3.58% than the contrast. The saving curing cost was 0.158 yuan per kg of dry tobacco leaf and saving cost rate 9.09% in bulk cur- ing barn with use waste heat of flue gas than the contrast. The appearance quality, grade structure and primary chemical composition had no significant difference be- tween bulk curing barn with use waste heat of flue gas and the contrast.

Analysis of Sulfur Dioxide Concentration Around Bulk Curing Barn Group

This study was conducted to analyze the spatial distribution of SO2 mass concentration around baking barn groups. A bulk curing barn group was selected as monitoring object, and SO2 concentration around it was monitored for 2 years. The results showed that the SO2 mass concentration within 30-130 m from the baking barn group exceeded the standard, and with the ground as reference, the SO2 mass concentration at the position 0.9-2.1 m from the ground exceeded the stan- dard. According to the limit value of the SO2 mass concentration for sensitive crops, the SO2 mass concentrations over the standard were concentrated within the range of 200-300 m. On the basis of establishment of ＂sulfur control＂, ＂sulfur reduction＂ and ＂sulfur avoiding＂ system, the SO2 emission status of baking barn groups could be improved from the conversion of heat supply method, the utilization of clean en- ergy and adjustment of crop sensitive period and sensitive area.

Existing Problems of Intensive Curing Barn and Optimization Analysis

Intensive curing barn is an important component of flue-cured tobacco pro-duction in China, with progress made. However, problems stil exist, such as lower heat energy utilization efficiency and slow equipment update. In the research, opti-mization ways of tobacco barn were analyzed in flue-cured tobacco production re-gions, and assessment was made on improvement effects, in order to provide refer-ences for highly-efficient and low-carbon development of curing barn.

Doing a Good Job in Inspection and Maintenance of Facilities and Equipments in Bulk Curing Barn

Due to the limited management funds and insufficient management efforts,curing barns in traditional tobacco area are outdated and equipments are seriously damaged,which affects the normal operation and increases the maintenance cost of bulk curing barns,bringing adverse effects on tobacco leaf curing in the coming year and the sustainable development of tobacco industry in the future.To ensure the normal operation of curing barns and effectively prolong the service life of curing barns during tobacco leaf curing,we should do a good job in the publicity of management and maintenance,improve the system of management and maintenance,raise funds for management and maintenance,inspect facilities and equipments,carefully maintain equipments in curing barn and strictly perform examination and inspection.

改良热泵密集烤房烘烤工艺及其效果分析

为进一步利用热泵密集烤房优势,解决热泵密集烤房与现有工艺不匹配、初烤烟叶化学成分提升不明显等问题,对传统三段式烘烤工艺进行改良,对初烤烟叶的主要化学成分、石油醚提取物、多酚类物质、香气代谢产物及评吸质量进行分析。结果表明:与传统三段式烘烤工艺相比,可变频密集烤房采用改良三段式烘烤工艺后效果较好,其初烤烟叶化学成分赋值提高8.9%,淀粉含量下降20.0%,中性致香物质含量提高0.7%,多酚类物质含量提高49.4%,评吸得分提高6.2%。说明改良三段式烘烤工艺可促进烟叶香气代谢产物的积累和化学质量、评吸质量的提高。综合分析,改良后的三段式烘烤工艺能够有效提升热泵密集烤房初烤烟叶质量,有较好的实用价值。

变容积密集烤房的CFD分析与试验研究

为保障密集烤房装烟密度,降低烘烤的能源消耗,研发一套适用于密集烤房的变容积系统。在完成变容积装置的设计后,基于CFD方法模拟分析装置与烟叶的不同距离对烤房内部气体分布均匀性的影响。通过烘烤试验获取实际烘烤数据,对模拟值加以验证。试验结果表明:当隔板与烟叶距离为0 cm时,流速不均匀系数Kv为0.40,温度不均匀系数Kt为0.41,距离为10 cm时,Kv=0.41,Kt=0.43;距离为20 cm时,Kv=0.42,Kt=0.49。装烟区9个测量点的温度模拟值与实测值基本吻合,误差在6%以内。变容积烤房在装烟量为一半时,相比常规烤房的燃料消耗可节约13.4%。研究结果表明:当隔板与烟叶距离为0 cm时烤房内部的气体分布最均匀;CFD模型与数值模拟结果具有可靠性;变容积装置具有较好的保温效果,可保证装烟密度,降低烤烟能耗。

不同新能源类型密集烤房烘烤效果研究

通过烘烤试验对比,从烤房建造成本、运行参数、烘烤能耗用工、控温精度、烤后烟叶外观质量、化学成分、经济效益等方面探索内置式生物质烤房、密闭式热泵烤房、光伏一体化烤房的烘烤效果,旨在筛选曲靖烟区最适宜的烤房类型,并为烟草行业的绿色可持续发展提供理论依据。结果表明,密闭式热泵烤房烘烤能耗和用工成本较低,控温精度、烤后烟叶质量、经济效益较好,是目前最适宜曲靖烟区的烤房类型;光伏一体化烤房建造成本高昂,且烘烤效果表现一般,目前推广难度较大,但可作为未来烤房的发展方向;内置式生物质烤房建设使用门槛较低,可在生物质颗粒供方市场成熟和电力配套设施不齐全的烟区加以应用。

移动式烤房关键参数及配套烟叶烘烤工艺优化

【目的】探究移动式烤房关键参数及配套烘烤工艺,为移动式烤房的推广应用提供理论依据。【方法】设计建造6个不同材质、规格和能源类型的移动式烤房,筛选综合性能最佳的移动式烤房;以传统密集烤房烘烤工艺为对照组,设3个不同的移动式烤房烘烤工艺处理组,分析不同烘烤工艺对烤后烟叶经济性状、感官质量和生化指标的影响,筛选最优移动式烤房配套烘烤工艺;对筛选出的最佳移动式烤房与传统密集烤房进行烘烤效果比较。【结果】以聚氨酯材料建造并采用U型包边方式的生物质烤房综合性能最佳,保温性较好。与传统密集烤房烘烤工艺相比,采用最优移动式烤房配套烘烤工艺的烤后烟叶上等烟比例显著提高15.8%(P<0.05,下同),均价显著提升4.2元/kg,香气物质总量显著提高37.29%,蛋白质含量显著降低5.46%,而氨基酸含量显著提高10.61%;同时,在最优移动式烤房配套烘烤工艺下,烤后烟叶的感官质量评价总分达82.1分,较传统密集烤房烘烤工艺显著提高。与传统密集烤房相比,移动式烤房的烘烤成本显著降低18.75%,烤后烟叶的上等烟比例显著提高87.50%,青杂率显著降低26.67%,感官质量评价总分显著提高0.6分。【结论】采用聚氨酯材料建造的移动式烤房安装便捷且综合性能最佳,采用优化后的移动式烤房配套烘烤工艺能促进烟叶内在物质转化,提高烤后烟叶感官质量,有效改善烟叶内在质量。相较于传统密集烤房,移动式烤房能在提高烟叶品质的基础上降低烘烤成本,具有良好的推广应用前景。

广东烟区内置式颗粒燃烧烤房示范与应用

为验证内置式颗粒燃烧密集烤房的性能和烟叶烘烤效果,使用内置式生物质燃烧机烤房、外置式生物质燃烧机烤房2种不同类型燃烧机烤房在同一烘烤工艺进行对比试验研究,并与传统燃煤烤房进行对照,从能耗成本、烤后烟叶外观质量、烟叶内在质量等方面对其使用效果进行分析。结果表明内置式生物质燃烧机烤房在烘烤成本、烘烤质量、经济效益、减工降本等方面都要优于燃煤烤房,与外置式生物质燃烧机烤房原理类似。内置式生物质燃烧烤房和外置式生物质燃烧烤房设备均为烟叶烘烤加热设备,在对原有密集烤房燃烧室进行小面积改造的情况下,即可替代燃煤进行生物质颗粒燃烧,自动供热烘烤烟叶。使用生物质燃料燃烧供热,试验烘烤成本稍高于燃煤烤房,但用工成本有相应减少,燃料较易获取,升温能够满足烟叶烘烤需要,污染小,属于国家鼓励推广的低污染能源,在新建新能源烤房中有较好的推广前景。

密集烤房排湿余热回收系统性能研究

针对密集烤房开式排湿造成的能源浪费问题,设计了一种利用重力热管的排湿余热回收系统。通过烘烤试验研究,得到了排湿气流的状态参数和燃料消耗量。结果表明,密集烤房排湿余热回收系统的平均显热效率为36.61%,平均全热效率为15.97%;与对照烤房相比,每公斤干烟可节约燃料0.22kg,节能率达到9.11%,该系统具有良好的工程应用价值。

密集烤房研究进展与展望

阐述了国内外密集烤房及其设备发展演变的历程,并就密集烤房与普通烤房对烘烤环境、烘烤过程中烟叶的变化和烤后烟叶品质的影响进行对比分析,在此基础上分析了造成目前密集烘烤烟叶外观质量降低、光滑烟形成、香气降低的原因,总结了密集烘烤的优缺点与特殊性,认为密集烤房将成为我国烘烤设备发展的必然趋势。

普通标准化烤房改造为密集式烤房适宜装烟密度研究

将标准化气流上升式普通烤房（2．7m×2．7m）改造为密集式烤房，按几种不同的编烟方式和竿距组合装烟进行烘烤，并分析烤后烟叶的内外品质，结果表明，普通1．5m长的烟竿，烟叶每束3片捆绑，每竿50束捆绑，竿距14-16cm效果较好。

密集烤房与普通烤房烘烤中烟叶色素和多酚含量的变化分析

为了探讨密集烤房与普通烤房烘烤过程中烟叶色素和多酚类物质含量的变化差异,测定了烘烤过程中关键温度点的色素含量、多酚氧化酶活性和多酚类物质含量。结果表明,密集烤房与普通烤房烘烤过程叶绿素总量、叶绿素a和叶绿素b含量变化差异较小。与普通烤房相比,密集烤房烘烤过程中类胡萝卜素含量总体较高;类叶比则表现出先升高后降低的变化趋势,烘烤结束时密集烤房的类叶比较高。密集烘烤过程中多酚氧化酶活性较低,多酚类物质含量较高,说明密集烘烤烤后烟叶趋于变黄充分,不易发生棕色化反应,有利于烟叶烤黄。

不同烤房烘烤过程中烟叶形态和物理特性的变化

【目的】在研究不同烤房烘烤过程中烟叶形态变化的基础上,探讨造成密集烤房烤后烟叶光滑、僵硬的原因,为优化密集烘烤工艺提供理论依据。【方法】以烟株中上部烟叶为试验材料,研究密集烤房与普通烤房烘烤过程中烟叶的形态变化,并比较烤后烟叶物理特性的差异。【结果】在密集烤房烘烤过程中,烟叶形态变化呈现出变黄期缓慢、定色期剧烈、干筋期又减缓的趋势;而在普通烤房烘烤过程中,烟叶形态变化相对平缓。密集烤房烤后烟叶各形态指标除上部烟叶纵向卷曲度外,烟叶纵向收缩率、横向收缩率、面积收缩率、厚度收缩率、横向卷曲度及中部烟叶纵向卷曲度均显著或极显著小于普通烤房的相应处理。与普通烤房相比,密集烤房烤后烟叶单叶质量、叶质重与叶片厚度较大,而含梗率、平衡含水率与拉力较小。【结论】密集烘烤条件下烟叶形态变化较小,并最终导致烟叶组织紧密及个别物理特性指标较差。

不同烘烤方式烘烤过程中烟叶表面烷烃类物质变化的研究

研究了不同烘烤方式对烘烤过程中烟叶表面烷烃类物质含量变化与损失的影响。结果表明，采用挂竿密集烤房烤后烟叶烷烃类物质总量损失最多，比烘烤前减少58．9％，损失主要发生在变黄期和干筋期；筐装密集烤房烤后烟叶烷烃类物质总量损失最少，仅比烘烤前减少13．8％，损失主要发生在干叶期（烤后72～96h）；散叶密集烤房和传统普通烤房烤后烟叶烷烃类物质总量损失居中，分别比烘烤前减少35．8％和32.3％，损失也主要发生在干筋期。因此，筐装密集烤房是解决目前挂竿密集烤房烟叶香气量损失较大的有效措施之一。

我国烤房的建设现状与发展方向

针对我国烤房建设现状,分析了当前存在的问题,展望了今后的发展方向,指出烤房建设要和现代烟草农业相结合,注重科技进步,重视节能减耗,集群化高标准建设。要尽快完善烤房建设体系,健全推广机制,为专业化烘烤的发展奠定理论基础。

热泵烤房与燃煤烤房应用效果对比研究

为探索高效、优越的烘烤方式,实现减工降本、提质增效的目标,以烤烟品种中烟100为材料,对比分析了热泵烤房和燃煤烤房在烘烤用工、能耗、烤后烟叶品质及经济性状等方面的应用效果。结果表明,与燃煤烤房相比,热泵烤房烤后烟叶颜色均匀,多橘黄色,组织结构疏松,主要化学成分比例更为协调,中上等烟比例较高,能有效减少用工费用50%以上,节省烘烤时间,平均节约烘烤成本38.36%,提升烟叶均价4.32%~7.76%,且各部位烟叶评吸质量综合评分较高,突出表现在香气质较好、香气量较足、杂气较少、刺激性较小、余味更纯净舒适。总的来讲,热泵烤房较燃煤烤房能有效地减少用工和降低成本,提高烟叶的烘烤质量。

不同烘烤方式烘烤过程中烟叶表面腺毛分泌物变化的研究

为研究不同烘烤方式对烘烤过程中烟叶表面腺毛分泌物含量变化与损失的影响,选择了传统普通烤房、挂竿密集烤房、散叶密集烤房和框装密集烤房等4种烤房类型,采用GC-MS定性,GC-FID定量的方法,分析烟叶表面腺毛分泌物含量。结果表明,挂竿密集烤房和散叶密集烤房烤后烟叶腺毛分泌物总量分别约为传统普通烤房的50%和60%,并且损失主要发生在干筋期。框装密集烤房烤后烟叶腺毛分泌物总量与传统普通烤房相当。因此,框装密集烤房是解决目前挂竿密集烤房烟叶香气量损失较大的有效措施之一。