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.

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.

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。

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。

可变频热泵密集烤房烟叶烘烤性能及效益分析

为解决传统密集烤房存在的问题,为变频热泵密集烤房在烟叶烘烤上的应用提供参考,设置加装变频风机的空气能热泵烤房、普通空气能热泵烤房、加装变频风机的传统燃煤密集型烤房和普通传统燃煤密集烤房4种处理,对不同类型烤房的烘烤性能与烟叶烘烤效益进行比较分析。结果表明:可变频热泵密集烤房烘烤的烟叶内在化学成分比例较好,淀粉含量显著低于其他3组处理;各处理中以可变频热泵密集烤房成本最低(887.96元/房),且烤后烟叶感官质量及评吸结果显著优于其他处理。综合分析,可变频热泵密集烤房在烟叶烘烤实用性上具有突出优势,能够有效提高烟叶烘烤质量和收益。

滇南丘陵烟区2种烘烤工艺应用效果对比研究

为进一步优化滇南丘陵某烟叶主产区烘烤工艺,采用对比烘烤试验,分析该烟区密集烤房常用的“三段十点烘烤工艺”(工艺A)和“三段六步烘烤工艺”(工艺B)2种烘烤工艺烤后烟叶的经济性状、烤坏烟数量及比例。结果表明:同等条件下工艺B能够明显减少挂灰烟、黑糟烟和级外烟数量,烘烤损失更低;对于上部烟叶,工艺B较工艺A烤后烟叶的均价提高0.5元·kg^(-1),增效较为明显。工艺A受普通烤房烘烤和三层密集烤房的烘烤技术影响较大,变黄期以“低温保湿变黄”策略为主,低温变黄时间偏长、排湿较少(小),整个烘烤过程设置的温度点较多,变黄期和定色期各相邻阶段的干球温度差异、目标任务差异相对较小,对操作人员判定烟叶变化是否达到目标、准确把握转火时机有较高技术要求,操控难度相对偏大。工艺B特点是高温变黄、低温定色、边变黄边排湿,慢升温,针对四层密集烤房上下层温差偏大的实际,干球38℃以前的低温变黄时间较短,以38℃为顶层烟叶主变黄温度,以42℃为底层烟叶主变黄温度,同时在42℃阶段提高了烟叶失水程度(顶层勾尖卷边、底层凋萎塌架),相对更有利于避免定色前期棕色化反应的发生。综上,相较于“三段十点烘烤工艺”(工艺A),“三段六步烘烤工艺”(工艺B)更加适用于滇南丘陵某烟叶主产区鲜烟叶烘烤特性、四层密集烤房性能特点,但要结合当年气候和鲜烟叶素质差异灵活操作。

基于积温积湿与聚类分析的密集烤房温湿度时空分布特征研究

为了明确密集烤房烟叶烘烤过程中的温湿度时空分布规律,提高烟叶烘烤效果,本研究采用密集烤房温湿度自动精准监测系统获取不同部位烟叶烘烤过程中烤房的环境参数,进行聚类分析和精准分类。结果表明,不同部位烟叶烘烤时,密集烤房内温湿度时空分布规律有一定差异。根据不同区域积温、积湿等情况,在下部叶、中部叶和上部叶烘烤过程中,可分别将密集烤房装烟室划分为3类、3类和4类区域,不同素质的鲜烟叶可与相应的区域进行精准匹配。

衡阳烟区上部烟叶不同装烟方式烘烤效益比较

[目的]探索适合衡阳本地上部烟叶的最佳烘烤方式。[方法]以云烟87为试验材料,对比分析常规挂杆烘烤、梳式烟夹烘烤、带茎烘烤3种密集烤房装烟方式对上部烟叶烘烤成本、烘烤效益及烤后质量的影响。[结果]与常规挂杆装烟方式相比,烘烤成本烟夹装烟方式有所下降,带茎烘烤反而增加;烤后质量方面,烟夹烘烤与挂杆烘烤基本持平,带茎烘烤提升明显,内在化学成分协调性最优;综合效益烟夹烘烤与带茎烘烤均有所提高,以带茎烘烤最优。[结论]带茎烘烤有利于提高衡阳烟区烤烟上部烟叶的质量,改善上部烟叶的可用性,提高烟农收益,具有较大的推广价值。

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。

密集烤房不同装烟方式对烟叶质量及效益的影响

为优化密集烤房装烟方式,充分发挥烤烟密集烘烤的优势,对散叶烘烤、烟夹持烟、烟竿编烟3种装烟方式烤后烟叶的外观质量、评吸质量、经济性状及烘烤能耗成本进行了比较研究。结果表明,烟夹持烟烤后烟叶橘黄烟比例比烟竿编烟烘烤高11.11%,散叶烘烤的杂色烟比例明显低于烟夹持烟和烟竿编烟;散叶烘烤和烟夹持烟烤后烟叶的评吸质量均优于烟竿编烟;散叶烘烤烟叶的中上等烟比例和均价最高;烟夹持烟烘烤的耗煤、耗电成本最低。综合烤后烟叶的经济性状和能耗成本,以烟夹持烟的效益最好。因此,在其他烘烤设施和烘烤技术配套的前提下,烟夹持烟可以替代传统的烟竿编烟;散叶烘烤是密集烤房装烟方式的发展方向之一。

热泵型烟叶自控密集烤房的应用研究

对热泵型烟叶自控密集烤房与普通烤房的性能及其所烤烟叶的品质进行了对比试验。结果表明,热泵型烟叶自控密集烤房性能较好,平面温差和垂直温差较小,风速适宜,通风排湿顺畅,烤房的能耗及用工减少;所烤烟叶颜色加深且色度均匀,平衡含水率和填充值适宜,出丝率高,化学成分间比例协调,香气质好,香气量足;说明热泵型烟叶自控密集烤房较普通烤房显著提高了烟叶的烘烤质量。

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。

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。

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。

“8点式精准密集烘烤工艺”的创新集成与应用

为了改善和提高密集烘烤烟叶质量,通过系统研究优化创新集成了"8点式精准密集烘烤工艺"。该工艺包括38、40、42、45、47、50、54和68℃等8个关键温度点及相应技术参数。烘烤时可使烟叶变黄和失水协调,有利于色素、淀粉、蛋白质等物质的降解转化及香气物质的形成和积累,烤后烟叶橘黄烟比例、上等烟比例和均价明显提高,杂色烟、青烟等下低等烟明显减少,评吸质量明显改善。通过推广应用,已取得了良好的经济效益和社会效益,具有良好的推广应用前景。