共查询到20条相似文献,搜索用时 203 毫秒
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造纸机的新型多通道烘缸 总被引:2,自引:0,他引:2
目前的造纸机烘缸大多采用虹吸管式冷凝水排出装置,由于受烘缸积水的影响,导致传统烘缸的干燥效率下降,纸页受热不均匀。基于此,介绍了对该传统结构进行改进的方法,采用多通道式冷凝排水装置,并将2种烘缸在干燥机理、传热效率和干燥设备的技术性能指标等方面进行了详细的比较,得出了多通道式烘缸干燥效率高。能耗小等优点。 相似文献
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模糊PID在卫生纸机烘缸进出口差压控制中的应用 总被引:1,自引:1,他引:0
烘缸进出口差压是表征烘缸是否积水的一个重要参数,通常处于波动状态。在实际控制中的通常做法是利用PID控制算法将其控制于一个具体的数值,但由于烘缸排水的非均匀性,导致上述控制目的难以达到。因此,本课题提出一种利用"模糊"思想来控制卫生纸机扬克烘缸进出口差压的新方法,将烘缸进出口差压分成五个区段进行模糊化,再利用模糊控制算法来调整PID控制器参数,控制扬克烘缸进汽热泵的开度,从而达到控制烘缸进出口差压的目的,使得烘缸进出口差压稳定在一个合适的范围内。通过仿真及应用表明,系统中热泵开度变化平稳,烘缸进出口差压被控制在许可范围内,烘缸能保持长期不积水状态。 相似文献
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在生产中及时判定烘缸积水的情况,并适时采取措施,排除烘缸内的冷凝水是提高洪缸单位出力,保证纸机正常生产的重要条件。高速纸机烘缸是否积水,不能单从烘缸排水管上的视镜有无流水来判定,而应根据以下几个因素综合判定。1根据第一段供缸进汽压力的变化来判断高速纸机的3段通汽一般都采用计算机控制,在工作车速、供汽压力和温度变化不大的情况下,一旦供缸积水,烘缸单位出力就会降低。为提高干燥部的干燥能力,计算机控制的第一段洪缸进汽压力会超常地提高,积水严重时,因干燥能力不足只得被迫降低车速。因此,其他条件无变化而一段… 相似文献
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介绍纸袋纸机在烘缸虹吸器改造并加装扰流棒前后烘干部性能的变化,特别是烘缸排水情况、传动电流、烘缸表面温度在改造后得到大幅改善,吨纸汽耗明显降低,干燥效率明显提高,并为大定量纸种高车速生产提供了运行条件. 相似文献
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J PISECKY 《International Journal of Dairy Technology》1985,38(2):60-64
This paper deals with developments in concentrating and drying milk products during the 1970s and to the present. These developments are characterized by:
- a considerable increase in both maximum and average capacity of milk spray dryers, as well as of total production capacity.
- a tremendous increase in the number of milk-based products being spray dried,
- upgrading the quality of products both in retention of nutritive values and tailoring of functional properties,
- a considerable improvement in the economy of production, and
- the introduction of sophisticated instrumentation through microprocessors and computer control.
The development of dryers with integrated fluid beds during that period are described in some detail. Two such types of dryer have been developed, the Compact Spray Dryer (CSD) and the Multi-stage Dryer (MSD). The integrated fluid beds in these dryers are stationary (non-vibrating) fluid beds having annular (CSD) and circular (MSD) shape, respectively, forming the base of the spray drying chambers. Apart from improved powder quality and production economy these dryers can also cope better with difficult products having high lactose and fat content.
Finally, expected future trends for further development of milk drying technology are discussed. 相似文献
- a considerable increase in both maximum and average capacity of milk spray dryers, as well as of total production capacity.
- a tremendous increase in the number of milk-based products being spray dried,
- upgrading the quality of products both in retention of nutritive values and tailoring of functional properties,
- a considerable improvement in the economy of production, and
- the introduction of sophisticated instrumentation through microprocessors and computer control.
The development of dryers with integrated fluid beds during that period are described in some detail. Two such types of dryer have been developed, the Compact Spray Dryer (CSD) and the Multi-stage Dryer (MSD). The integrated fluid beds in these dryers are stationary (non-vibrating) fluid beds having annular (CSD) and circular (MSD) shape, respectively, forming the base of the spray drying chambers. Apart from improved powder quality and production economy these dryers can also cope better with difficult products having high lactose and fat content.
Finally, expected future trends for further development of milk drying technology are discussed. 相似文献
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对造纸行业使用的钢制烘缸和铸铁烘缸的优点和缺点进行了比较.就纸机钢制烘缸的材料选择和结构设计、制造以及使用中存在的问题进行了分析.在技术方面,应该加快更新钢制烘缸技术规范的步伐,适应高车速和多品种纸机生产对烘缸性能的要求,减少钢制烘缸的制造成本,降低纸厂在钢制烘缸设计寿命期内的缸面处理费用. 相似文献
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《Food chemistry》2003,82(1):161-167
Instead of measuring the real water content, very often drying mass loss is determined. Not only water contributes to this mass loss, but all volatile materials under the applied drying conditions. On the other hand, very tightly bound water may elude detection. The mass loss by drying does therefore not necessarily correspond to the water content of the sample. To accelerate analyses, in comparison with the classical oven method, more efficient heating sources have been introduced. Infrared dryers belong to this category. This more vigorous heating tool involves a higher risk of decomposition of the sample with production of further volatile compounds. The danger of obtaining erroneous results is particularly high for heat-sensitive products, such as sugars. The objective of this work was to find parameters for the infrared drying of sugars and products with a high sugar content such that the results correspond to those determined by the Karl Fischer titration which selectively measures the water content. 相似文献
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《造纸信息》2015,(8):108-108
<正>Sun Paper tissue base paper production line put into operation successfully on June 16th,2014.The tissue base paper plant began construction in August 2013,and all of construction work was completed in November 2013.The production line began installation officially in January 2014,the key equipment of the production line Yankee dryers installed smoothly on May 16th,the production line entered into the commissioning phase. 相似文献
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介绍烘干机的工作原理 ,分析制约水刺生产线产能的重要因素 ,优化热油炉的控制算法 ,提高水刺生产线的产能。 相似文献
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干燥是挂面生产的重要工艺环节,干燥能力和能耗是产品成本的重要组成部分。本文对3种主要挂面干燥设备(隧道式、索道式、改良索道式),以及工艺的干燥能力、能耗、稳定性开展在线测试,分析了测试结果。初步结果认为,挂面干燥过程的"三阶段"划分和设计不同的干燥过程控制参数,符合节能、高效、高质量的生产目标。合理的干燥工艺和烘房结构,以及优化的干燥过程控制参数,可显著提高产量(42.91%),降低能耗(-24.56%),缩短干燥时间(-12.50%)。拟实现干燥工艺控制过程的智能化,首先应是设计合理的干燥烘房结构,确定干燥工艺的关键控制要素和关键控制点;其次是实现干燥过程温度湿度控制与挂面在线含水率测定结果的联动,以及提升挂面在线含水率监测设备的稳定性和环境耐受性。而对挂面干燥动力学、热力学的系统研究,是干燥工艺智能化的基础和前提。 相似文献