尿素旋风洗除尘工艺

阐述了旋流水洗除尘工艺回收尿素风选尾气中的尿素粉尘,对该工艺流程及旋流板设计作了较详细的介绍,并对改造效果作出评价。     

旋流板在薄膜蒸发器中的应用

我厂尿素一段薄膜蒸发器是由列管换热器和除雾器所组成。除雾器由于除雾效率低,形成夹带,造成除雾器上部填料处尿液结晶,同时也夹带到后工序设备,造成结晶和腐蚀,给生产带来不便,又除雾器结构复杂(见图1)。所以在大修时我们采用了旋流板结构。旋流板具有除雾量大、允许气速高、结构简单、不易堵塞、造价便宜,并具有较高的除雾效率。一、旋流板的设计条件及参数 1.已知条件: 除雾器直径 D=1000毫米空速 W=1.5米/秒尿素出口流量:L=1.5米~3/时 2.选取参数①径向角β为负(即叶片为外向)     

提高SNCR效率

意大利ECOSPRAY Tech-nologies将尿素喷射改为气体雾化喷射,利用750~800℃或更高温度的三次空气通入蒸发反应器内,尿素溶液通过双旋流喷头雾化喷入反应器内,雾化尿素遇热后,其附着水和结晶水快速蒸发,固态尿素遇热分解成NH3和HCNO进入催化过滤反应器内。在催化过滤反应器内,粉尘被移除,同时催化剂促进HNCO与水作用,生成NH3和CO2。气体中含有5%的NH3气体,重新喷入预热器系统内。这大幅提高了去除NOx的效率。     

Φ1200mm尿素合成塔的修理

1Φ1 200 mm尿素合成塔结构Φ1 200 mm尿素合成塔为多层包扎式结构,衬里为316 Lmod尿素级不锈钢,厚度为8 mm;第1层容器板材质为16 MnR,厚度为12 mm;盲层板和多层板材质为15 MnVR,厚度为6 mm。塔内原有3层旋流板和2层多孔板。2007年,为提高CO2转化率、减少物料返混,增设了13层GC型塔板,现共有18层塔板。2存在的问题该尿素合成塔自投运以来,严格按工艺指标进行操作;并按规定定期检验,每次检验后均对衬里出现的缺陷进行了修复,衬里使用良好,没有出     

旋流在气流床气化炉中的应用

在气流床气化炉内高温高压的环境下,气固混合是影响气化炉效率的重要因素,而旋流在强化气固混合方面已在燃烧中得到广泛使用,文中综述了旋流在气流床气化炉中的应用。首先介绍了旋流的数学描述,包括旋流的概念,旋流N-S方程的表示方法以及其解析解,旋流的解析解均是在一定假设前提下得到的,具有一定的局限性;其次,介绍了旋流的特性和生成方式,主要通过切向入口、旋流叶片和机械旋转引入旋流;然后介绍了旋流在气化炉中的应用,包括喷嘴旋流和炉膛旋流2种,并结合具体结构展示了旋流的作用,主要有增强混合和便于排渣;最后对旋流在气化炉中的应用进行了总结和展望。     

海藻液增效尿素的研究开发

以海带等藻类植物为原料,利用大肠杆菌基因工程菌生物发酵制备海藻液增效剂。将提纯浓缩的海藻液增效剂与熔融的尿液按一定比例,在高塔旋流喷射器中喷洒成雾状,在下落过程中均匀混合,形成包含海藻液增效剂的尿素颗粒。     

旋流燃烧器发展历史及国外典型旋流燃烧器

介绍了旋流燃烧器的发展历史和传统旋流燃烧器、分级燃烧式旋流燃烧器、低NOx旋流燃烧器的结构及原理。对国外的典型旋流燃烧器结构及特点进行了详细的介绍,并指出了在应用中存在的问题,对开发国产新型低NOx煤粉燃烧器提出了一些建议。     

燃烧器头部旋流器旋流槽加工误差分析及工艺改进

<正>在燃烧器的结构中,头部旋流器旋流槽的大小对出风量、风速以及火焰长度有直接的影响,但是在实际的旋流槽加工中,由于多方面的影响,旋流槽宽度误差较大,本文就实际的旋流槽加工工艺进行了实验分析,并对工艺计算方式进行了优化,大幅提高了旋流槽加工精度。1加工误差的问题描述典型头部旋流槽加工图如图1所示。在前期加工过程中,旋流槽的误差形式表现为:梯形截面的上口符合尺寸、下口超差,超差值在0.8~1mm     

催化裂化沉降器新型高效旋流快分器内气固两相流动

用CFX软件对催化裂化沉降器新型旋流快分器的气相流场进行了三维模拟,湍流模型采用雷诺应力输运方程模型.计算结果与用五孔探针测试的气相流场实验结果吻合很好.采用离散轨道模型对该旋流快分器内颗粒的运动情况进行了计算,并由此估算了旋流快分器的分级效率和总分离效率.模拟结果表明：该新型旋流头可消除现有旋流头喷出口附近的短路流,更有利于提高旋流快分器的效率.两种结构形式的旋流快分器分离效率的计算对比说明：在旋流头处加入一个内构件,是很有价值的改进.     

旋流板塔在涂装废气除尘除雾方面的应用开发

在前人对旋流板分离技术的研究和应用基础上,提出将旋流板塔应用在涂装废气除尘、除雾处理当中;通过流体力学计算软件对选取的9种旋流板参数的塔体模型进行数值模拟研究,分析出旋流板结构参数对旋流板塔分离性能的影响规律,优化结构参数并根据实际工况进行数值模拟,缩短设计开发周期和节省费用。从样机的实际运行状况来看,该旋流板塔能较好地解决了目前存在的问题,同时说明CFD模拟结果对旋流板塔的设计和优化具有一定的理论指导意义。     

旋风分离技术研究进展(英文)

Centered on the techniques and industrial applications of the reinforced cyclonic separation process,its principles and mechanism for separation of ions,molecules and their aggregates using polydisperse droplets are discussed generally;the characteristics and influential factors of fish-hook phenomenon of the grade efficiency curve in cyclonic separation for both gas and liquid are analyzed;and the influence of shear force on particle behavior(or that of particle swarm) is also summarized.A novel idea for cyclonic separation is presented here:enhancing the cyclonic separation process of ions,molecules and their aggregates with monodisperse microspheres and their surface grafting,rearranging the distribution of particles by size using centrifugal field,reinforcing the cyclonic separation performance with orderly arranged particle swarm.Also the investigation of the shortcut flow,recirculation flow,the asymmetric structure and non-linear characteristics of the cyclonic flow field with a combined method of Volumetric 3-component Velocimetry(V3V) and Phase-Doppler Particle Anemometer(PDPA) are elaborated.It is recommended to develop new systems for the separation of heterogeneous phases with cyclonic technology,in accordance with the capture and reuse of CO 2,methanol to olefins(MTO) process,coal transfer,and the exploitation of oil shale.     

影响旋流微泡浮选柱工作的因素分析

介绍了旋流微泡浮选柱的工作原理及结构,分析了影响其工作的各主要因素,为更好的使用旋流微泡浮选柱提供依据。     

振动载体旋流干燥机在阻燃剂干燥上的应用

介绍了振动载体旋流干燥机的结构、原理、对阻燃剂干燥的新工艺,并对其干燥机理进行了分析,给出了该机干燥的实用例。     

旋流管式车辆空气滤清器过滤技术研究

针对旋流管式空气滤清器作为车辆的空气预滤器,在发动机部分负荷下存在旋流管过滤效率低的情况,提出了两种提高旋流管在发动机非设计工况时过滤效率的技术措施:预滤器进气自适应调节技术和抽尘自适应调节技术。通过利用这两种自动调节技术,使旋流管式预滤器在发动机的全工况范围内都工作在设计范围以内,进而保证高效过滤,解决车辆在非设计工况时因为预滤器的过滤效率低而造成的发动机空气滤清器维护保养周期短,影响动力性等问题。     

An experimental study of copper sulfide flotation in a packed cyclonic–static microbubble flotation column

A method using a cyclonic–static microbubble flotation column packed with fluid guiding media was proposed for improving flotation efficiency of copper sulfide. The installation of packed fluid guiding media in a cyclonic–static microbubble flotation column was for changing flow pattern in 10 the column by avoiding strong cyclonic flow in the upper region of the column, which can cause bubble-particle detachment. Therefore, the attached particles can be more likely to enter the froth zone instead of swirling in the column. The flow rectification contributed to a smaller bubble size in the column and significantly reduced the number of big bubbles with diameter above 1 mm. This scenario was caused by the damping of swirling liquid motion where bubbles tended to 15 concentrate and coalescence in the center of an eddy. The packed fluid guiding media changed the hydrodynamics in the upper column from a cyclonic flow to a gentle flow and as a result improve the column separation. The application of packed fluid guiding media can decrease the bubble-particle detachment and the flotation recovery of copper sulfide could constantly improve with the installation of packed fluid guiding media in the FCSMC column.     

预浮选式浮选柱分选细粒粉煤的实验研究

分析了传统旋流微泡浮选柱的应用现状,阐述了浮选入料性质及条件特别是入料浓度对浮选柱分选效果的影响,提出了采用预浮选式旋流微泡浮选柱分选解决高浓度细粒煤浮选的新方法,并通过试验论证了该方法的可行性,对工业现场的浮选作业具有一定的指导意义。     

Bubble size distribution in cyclonic zone of a novel flotation column

In order to investigate bubble size distribution (BSD) in the cyclonic flotation column, a series of tests were conducted to study flow velocity distribution (FVD) and BSD by using the method of particle image velocimetry (PIV). Foaming performance of the n-octyl alcohol is more applicable than both of n-butyl alcohol and terpenic oil. At different circulation volume conditions, BSD range lies in 0–800 μm, and a large number of tiny bubbles (<90 μm) are generated. Besides, the curve presents a normal distribution in 90–180 μm. With the increase in circulation volume, bubble size decreases. BSD determined by cyclonic flow effect plays a crucial role on bubble mineralization with fine particle in cyclonic zone of the flotation column.     

Sugarcane Bagasse Drying in a Cyclone: Influence of Device Geometry and Operational Parameters

Sugarcane bagasse is becoming more and more commonly used in generating electrical energy, steam, and bioethanol. Drying is important in sugarcane and other types of biomass because it can be used to improve the calorific value and overall energetic use. In this work, sugarcane bagasse was treated by drying in a cyclonic dryer. The influence of the geometry of the device (the conical part of the cyclone) and process parameters (bagasse mass flow rate and temperature) were tested. The modification on the conical part was related to two different angles and with two different inferior outlets (B). Experimental design was carried out for each geometry. The independent variables were the drying agent temperature (35 to 275°C) and the bagasse mass flow rate (0.1 × 10^?2 to 2.9 × 10^?2 kg s^?1). The air flow rate was kept constant at 7.5 × 10^?2 kg s^?1. The dependent variables were moisture reduction (MR) and average particle residence time (t_res) in the cyclonic dryer. For both cyclonic geometries, it was observed that MR was directly proportional to the temperature and inversely proportional to the bagasse mass flow rate. t_res was also inversely proportional to the bagasse mass flow rate. Decreasing B tended to increase tres and MR.     

旋流分料器的结构与性能研究

<正> 1 引言 随着循环流化床技术的日益发展,许多生产工艺均采用外部循环的方式来提高粉料成品的合格率,在这些生产工艺中(如水泥生产),一部分固体粉料要循环返回反应器,另一部分则作为成品排出循环系统.分料器是实现这一目的的关键设备.在水泥生产中,使用较多的分料装置有:安装在窑尾的溅料扬撒分料装置、溜管分料装置及输送分料装置.它们的共同特点是靠机械部件的运动来调节所分配的两路物料量之比.由于水泥生产具有高温的特点,降低了使用机械运动部件的可靠性和寿命.为此,彭新战、周勇敏等开发了气动分料器,达到了高温下无机械运动部件分料的目的,但各路调节风受到初始流化速度限制,故调节范围小,灵活性较差.本文在上述工作基础上,研究既能适应高温操作要求,又能在较大调节范围内较灵活可靠地调节分料的旋流分料器。