采用简化计算公式进行格子体设计

详细阐述了玻璃熔窑蓄热室格子体设计的思路。指出了玻璃熔窑炉膛内的火焰温度和炉壁温度的关系,助燃空气的预热温度和排出烟气的温度是互相锁定的关系,达到助燃空气预热温度是蓄热室格子体设计的目标。重点介绍了格子体设计的简化计算公式,以及国投线500 t/d浮法玻璃熔窑蓄热室按简化计算公式进行格子体设计的情况。还采用TECO经验公式对计算结果进行了对比分析。     

1000t/d级特大吨位浮法玻璃熔窑设计

介绍了千吨级特大吨位浮法玻璃熔窑的四大经济技术指标的设计思路,对千吨级玻璃熔窑主窑体、小炉、蓄热室等各部位窑体结构,以及熔化区炉膛火焰空间容积热负荷与玻璃液面受热强度进行了计算,并根据设计出的格子体参数,对助燃空气能够达到的预热温度和格子体热平衡进行了计算。     

玻璃熔窑蓄热室筒形、条形、十字形格子砖的应用对比

以新建1000t/d浮法玻璃熔窑为例,分别计算了典型的筒形砖、条形砖、十字形砖格子体的相关数据。这些数据包括:蓄热室腔道平面尺寸、单侧蓄热室的格子孔数量、助燃空气和烟气在格子孔内的流速、格子体上下部的传热系数、全窑格子体的总传热系数、需要的格子体换热面积、格子体高度、全窑格子砖的重量。最后对三种类型格子砖的优缺点及使用性能进行了分析对比。     

浅析浮法玻璃熔窑蓄热室的设计技术

１－引言蓄热室设计涉及到熔窑的规模、熔窑的燃烧控制、蓄热室的结构、格子体材料的配备等多方面因素,在熔窑设计中占有重要的地位,它的设计水平直接关系到熔窑的寿命、能耗、玻璃的熔化质量等。浮法玻璃熔窑蓄热室应具有如下特点：（１）消除蓄热室内格子体的过冷点和过热点,使预热空气温度均匀;（２）能灵活调节烟气和助燃空气在蓄热室内的进出;（３）能满足助燃空气预热到较高温度的要求;（４）能合理控制熔窑的燃烧;（５）蓄热室的表面散热小;（６）蓄热室在本窑期内不更换格子体。２－蓄热室的设计技术２－１采用“前置式”箱…     

换火周期与熔窑火焰温度波动

在熔窑换火周期内，随着格子体温度的降低，预热空气温度和火焰温度随之降低，通过分析李赫特式格子体蓄热室热交换，计算出格子体体积、换火周期与预热空气温度和火焰温度波动值之间的对应关系，结论指出，要使火焰温度稳定，除了格子体应有足够大的体积，还应该有恰当的换火周期。     

国外700t/d浮法玻璃熔窑的窑体尺寸和蓄热室参数

以pilkenton公司在欧洲建造的700 t/d浮法玻璃熔窑为例,采用反推算法分析判断其熔窑的主体结构尺寸和蓄热室格子体的参数。对其蓄热室参数的腔道尺寸、助燃空气预热温度、排烟温度情况进行了详细的分析推算。     

硅酸钠熔制与熔窑技术问条（四）

换火是将燃烧所需要的空气，煤气分别轮流送入两边的空气，煤气蓄热室预热，将废气轮流通过两边蓄热室加热格子砖，当废气从小炉排出，通过蓄热室中的格子砖孔道时，将它的一部分热量传递给格子砖而使其加热，换向以后，从燃烧用的空气和煤气流过这些已加热的格子砖，吸阴砖所蓄蓄积热量的一部分而提高了自身的温度，这样在蓄热室中交替地流过废气和空气或煤气，以格子砖作为中间媒介进行热交换，就可利用废气的热量以完成空气和煤气的预热过程，为了稳定焙化温度，不让格子砖上部温度过高（不超过上部格子体选材所允许的工作温度），少格子砖耐火材料的烧损，同时具有良好的换热效果，一般每间隔20－30分钟换向一次，在换向行程中，交换器有短时间的中立，为减少煤气浪费和影响窑内温度，要求换火操作行程时间越短越好。     

玻璃池窑内助燃空气增湿处理的应用研究

以一座熔化面积为16.5m~2的蓄热式马蹄焰池窑为例,通过计算说明:在其它条件不变的情况下,对助燃空气进行增湿处理后,助燃空气预热温度提高了60℃,节油率达60%,每年可节约重油100t.要求是稍增加烟囱的高度和增加一套调节、控制汽量的装备;表明对助燃空气增温处理是一项合理可行的节能措施.     

考贝式热风炉烟道余热的利用

一、概述我厂现有33米~3高炉一座,年产钙镁磷肥6万吨,配套考贝式热风炉三座,每座热风炉总蓄热面积627米~2,每米~3高炉受热面积57米~2。由于高炉的更新扩大,热风炉总换热面积离工艺要求差距较大,使热风炉格子孔气流速度过大、格孔温度下移、拱顶温度下降、烟道排烟温度高;加之煤气发热值较低,燃烧不稳定,蓄热能力降低、送风温度下降、焦比高。为解决这个矛盾,针对我厂热风炉烟道排烟温度一般高达450～550℃(约占支出总热量的25％)的情况,为此,我厂自行设计按装了三套余热器,回收了烟道废热,用来预热助燃空气,从而提高了     

一段转化炉设置燃料油及空气预热器的经济效益

吴泾化工厂大型合成氨装置的设计中,为降低一段炉排烟温度,提高热效率,降低油耗,在一段转化炉对流段中设置了7组燃料油预热器及8组助燃空气预热器。所花投资约30万元,在满负荷情况下按27万吨氨/年计,每年可回收4000吨柴油,约4个月投资就可回收。实际运转情况是:由于原料油及氨平衡等问题,长期未能满负荷运转,平均在日产500吨左右水平。由于负荷低,对流段中的燃油及助燃空气预热器的换热面积偏大,所以物料预热后的温度都较设计值为高。燃油预热器设计值为室温至100℃,实际可达110℃;燃烧的空气过剩系数设计值为1.15,实际上由于转化炉     

Katalytische Abluftreinigung: Verfahrenstechnische Aufgaben und neue Lösungen

Catalytic air purification; Challenges and new solutions. The integration of regenerative heat exchange into the catalyst bed allows for the autothermal operation of catalytic air purification with a low content of combustible gas. Concentrations corresponding to an adiabatic temperature rise of less then 20 °C can be processed without an additional heat source; in case of higher concentratons a side stream withdrawal allows for the utilization of the total heat of combustion at the highest reactor temperature. The feedback of heat due to the integrated heat exchange gives rise to an unusual reactor behaviour. An analogy of fixed bed reactor operation with countercurrent heat exchange is used to derive simple equations for reactor design and operation. If conventional catalyst packings are replaced by monolithic catalysts, substantial reduction in pressure loss and/or packed bed volume can be obtained. The corresponding relations are briefly discussed.     

蓄热式钢包烘烤过程中包内高温低氧特性的数值模拟

为了分析入炉气体的预热温度对高温空气燃烧过程的影响,综合考虑体系的质量、动量、能量守恒以及燃烧体系的组份平衡,建立了煤气-空气双预热的三维非稳态燃烧数学模型,并以CFX4.3为计算平台,耦合流体流动、燃烧和换热过程,首次对蓄热式燃烧过程中高温低氧特性进行了数值研究,得出了在不同预热温度时,燃烧室内气体温度场和氧气浓度场分布. 结果表明, 提高气体预热温度有利于加快燃烧进程,提高燃烧室内气体的整体温度及温度均匀性,降低局部氧浓度.     

高热导率材料对蓄热室传热的影响

采用蓄热式高温空气燃烧技术代替传统塔式锌精馏炉方孔式陶土换热器技术,并对蓄热室的部分材料进行改进。用热导率较高的耐热钢小球代替部分蓄热体,并采用数值模拟对改进后的蓄热室温度分布及功率的变化进行考查。结果表明,蓄热室内温度分布的均匀性明显提高,尾部蓄热室传热效果增强。高温段向尾部偏移,有效利用了蓄热室的尾部区域,且预热空气温度得到显著提高。     

高效节能内燃烧式热管的创新设计

本文基于目前蓄热蜂窝陶瓷的发展与应用,介绍一种内燃烧式节能热管。这种设备采用分步均匀燃烧,降低氮的氧化物的排放,提高助燃空气的预热温度,相对提高了理论燃烧温度,提高了燃料热值的利用率。     

高效节能内燃烧式热管创新设计

根据目前蓄热蜂窝陶瓷的发展与运用。本文基于蓄热蜂窝陶瓷的运用,介绍一种内燃烧式节能热管,采用分步均匀燃烧降低N的氧化物的排放,提高助燃空气的预热温度,相对提高了理论燃烧温度,提高了燃料热值的利用率。     

无霜空气源热泵系统冬季除湿性能初步实验

通过对比现有的空气源热泵空调系统的优缺点，提出了一种新型无霜空气源热泵空调系统。该热泵系统最大的新颖之处在于热交换塔实现了“一塔三用”，不仅冬季可以无霜高效运行与再生，夏季蒸发冷却后性能也有所提升。通过搭建该系统实验平台研究了溶液塔入口空气温湿度、空气流量、溶液入口温度、溶液流量、溶液质量分数对除湿性能及空气出口温度与溶液出口温度的影响，结果表明：出口空气与溶液温度随入口空气温湿度、流量、溶液温度、质量分数的升高,溶液流量的下降而升高；溶液塔的除湿效率主要受风量和溶液流量的影响，而入口空气温湿度、入口溶液温度、溶液质量分数影响很小，溶液塔的除湿量随着室外空气湿度的升高、入口溶液温度的降低、空气流量和溶液流量的升高而升高。     

Synthesis of Sinterable β-SiC Powders by a Solid Combustion Method

A solid combustion method for obtaining sinterable β-SiC powders from Si and C mixtures is described. The method is similar to the thermal explosion method in which a proper preheating of the reactive mixture enables a substantial increase in the temperature of the mixture, due to the heat of reaction, in a short time. The characteristics of the powders obtained by the method are given. Both a high chemical purity of the powders, which is due to the high temperature of synthesis, and an adequate BET surface area of the powders, obtained after vibratory milling, enable these powders to be used for producing sintered SiC materials.     

Effect of process variables on bulk development of air‐textured poly(trimethylene terephthalate) bulk continuous filaments

Bulk development of air‐textured poly(trimethylene terephthalate) (PTT) bulk continuous filaments was studied by varying two texturing parameters, yarn preheating and texturing hot air temperatures. The yarns were subsequently heat treated from 80 to 160°C. Bulk was found to go through a maximum with increasing heat‐treatment temperature because of two competing mechanisms. Upon heat treatment, the fiber shrunk and developed bulk; heat treatment also simultaneously induced structural reorganization through annealing and stabilized the fiber against shrinkage. When the later mechanism became dominant, bulk development decreased with further increase of heat‐treatment temperature. The temperature at which the maximum occurred increased when the yarn preheating or texturing air temperatures were increased. Depending on the extent of annealing and structural reorganization during yarn preheating and during texturing, fibers with equivalent bulk measured at a single temperature did not behave the same way over a range of heat‐treatment temperatures. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1011–1017, 2004     

助燃空气对乙烯裂解炉NOx排放的影响

乙烯裂解炉内复杂物理化学过程耦合模拟与优化能够满足乙烯装置对高效率、低污染和低成本的设计和操作要求，对提高乙烯工业的竞争力具有重要意义。针对简单燃烧机理难以准确预测炉膛燃烧生成NO_x浓度分布的弊端，提出了在裂解炉使用更准确的简化GRI-Mesh 3.0机理结合涡耗散概念(EDC)模型的方法，并对Sandia Flame D的燃烧过程进行计算流体力学(CFD)模拟，验证了此耦合模型的可靠性。在已建立的燃烧模型的基础上，研究了助燃空气对降低裂解炉NO排放的影响，结果表明：在满足裂解炉热效率的情况下，空气预热温度为300~600 K、过量空气系数为1.1时降低NO的效果最佳。     

Enhancement of Energy Efficiency of a Chemical Heat Pump-Assisted Convective Dryer

In earlier studies we have shown by simulation and experimental studies that the proposed chemical heat pump (CHP) unit can be used to recover waste heat from dryers and reuse it by storing and releasing heat with upgrading the temperature or by dehumidification. However, the final thermal energy production efficiency of the CHP for drying was found to be low. In this paper we present experimental results to demonstrate the potential for improved heat-recovery/storage and the heat-release/production of hot dry air for batch drying applications using the heat enhancement mode of the CHP. A new laboratory scale experimental CHP dryer system was built utilizing the calcium oxide/calcium hydroxide hydration/dehydration reversible reaction. The aim of this study is to improve the efficiencies of the heat recovery from heat source in the heat-storage step and the hot dry air production in the heat-release step of the CHP for heating up the air to around 100°C. The results of this experimental study utilizing a new reactor design showed that the shallow reactor/heat exchanger could accomplish 94% chemical heat storage and produce 100°C air at better than 75% efficiency for the reaction heat by controlling the preheating condition. The reaction conversion reached 90% in these experiments. The proposed CHP-assisted convective dryer system is found to be energy-efficient over a wide temperature range of industrial interest.