2 500t/d水泥生产线窑尾电收尘器改造

近几年来随着国家对新型干法水泥生产环保要求的不断提高,<水泥工业大气污染物排放标准>明确规定."到2010年1月1日起,现有的水泥生产线窑尾粉尘排放浓度低于50mg.Nm3.对水泥窑尾粉尘排放浓度作了严格的要求,规定现有的水泥窑电收尘器做到在生产工艺波动的情况下仍能正常运转,禁止非正常排放.如何能达到新标准要求,是电收尘器亟待解决的问题.     

收尘器技术进展

发达国家新型干法预分解生产工艺、大型水泥设备、自动化装备及各种配备件的研制情况与最新动态,一直为我国水泥界人士所关注。他山之石,可以攻玉,从2003年起,本刊将“国际视窗”作为常设重点栏目,每期拿出一定篇幅,及时介绍国外水泥行业的焦点、热点,报道各大水泥公司科研设计成果,尤其是实用性强的新工艺、新装备,以满足读者了解、掌握国外同行技术装备进展的需求。我们欢迎各单位和众多读者与《中国水泥》杂志社联系,“点菜下单”。我们将尽其所能,刊出相关文章与信息;同时也欢迎广大作者能提供稿件,共同为我国水泥工业现代化作出贡献。     

窑尾收尘器技术经济分析

1 窑头、窑尾除尘器方案 随着新标准的出台,人们对新型干法水泥熟料生产线水泥窑尾使用电收尘器还是袋收尘器更加关注.鉴于过去一些水泥厂窑尾电收尘器排放浓度(标准状况)大都超过50 mg/m3,一些人的印象中,窑尾使用电收尘器达不到新标准的排放要求.实际上,电收尘器在设计、制造、安装、使用得当的情况下,完全能满足新标准的要求.如合肥水泥研究设计院应用在国投海南水泥有限公司2 500t/d新型干法水泥熟料生产线窑尾、窑头电收尘器的出口排放浓度(标准状况)分别为42.5 mg/m3,26.6 mg/m3;     

我厂立式电收尘器的改造

０前言我厂有４条３．０m×８８．６５m湿法窑水泥生产线,窑尾均配有４０m２立式电除尘器。立式电除尘器大多应用于老式水泥回转窑的窑尾,因技术和管理等原因,除尘效率难以大幅度地提高,除尘器出口粉尘排放浓度长期不能达到国家环保要求。一些水泥厂已将立式电除尘器改造成为卧式电除尘器,但目前国内仍有数十台设备在使用。本文就我厂对立式除尘器实施成功改造的经验作一介绍。１立式电除尘器存在问题我厂立式电除尘器运行故障统计见表１,运用中存在的主要问题,则主要有下述方面。（１）电除尘器的原星形阴极线不易张紧（其采用的是…     

电收尘器处理窑尾废气技术

在当今世界,除了北美地区,水泥回转窑窑尾废气处理系统中传统的除尘方法都是采用电收尘器。国内多数企业使用电收尘器的历史较长,经验较多,都很适应。特别是在湿法窑和半干法窑窑尾废气处理系统中使用电收尘器时除尘效果很好,且易操作。但是在实际应用中,往往遇到许多技术问题,特别是新型干法悬浮预热窑窑尾废气的工艺参数,诸如烟气量、烟气化学成分、含尘浓度、粉尘比电阻等值经常波动较大,给电收尘器的操作使用带来一些麻烦,许多用户尤其一些中小厂家还没有完全掌握这门技术,其运行效果不尽人意,不能达标。笔者将多年积累的这方面的设计和…     

电--袋收尘器的开发和应用

1电—袋收尘器的开发电收尘器是利用粉尘颗粒在电场中荷电并在电场力作用下向收尘极运动的原理实现烟气净化的。在一般情况下,当粉尘的物理、化学性能都适合时,电收尘器可达到很高的收尘效率,所以,它是目前广泛应用的一种收尘设备,但它也存在一些不足。首先,收尘器的收尘效率受粉尘性能和烟气条件影响很大。例如:我们曾在1台立窑电收尘器上进行实验,当窑处于浅暗火操作,烟气温度为70～80℃时,电收尘器工作正常,目测烟囱看不到烟。但当窑处于深暗火操作,烟气温度降至45～60℃时,电收尘器虽仍工作在40～50kV,但烟囱浓烟滚滚,其排放浓度与电收…     

一种新型的袋收尘器控制方法

在国家对环境保护日益严格要求的今天,收尘器的正常运转是保证新型干法水泥生产线能否正常生产的一个重要因素,也是关键主机设备之一。一般来说,当前水泥工业使用的收尘器有电收尘器和袋收尘器两种,而袋收尘器相对于电收尘器又有以下一些优点：1．能处理温度高、湿度大的粉尘烟气;2．长期工作稳定可靠;3．除尘效率高,维修及换袋也比较方便;4．能量消耗低,     

GZ-SM布袋收尘器

根据资料介绍,我国近一半的防污染设施不能正常运转,难以发挥应有的投资效益和环境效益;国内水泥企业现在安装使用的回转反吹扁袋收尘器有1/3报废,有1/3排放不达标,只有1/3正常运行。特别是在高湿环境下,各种布袋收尘器结露严重,不能正常使用。     

传统电除尘器到袋收尘器的升级改造

1前言 自从工业化以来,静电除尘器和袋除尘器一直是工业生产工程中普遍采用的两种高效除尘装置。在大风量,高温,高湿的工况场合,静电除尘器曾经占领着主导地位。在新的排放标准实施之前,水泥行业中的窑头篦冷机废气处理和窑尾废气处理90％已上均采用静电除尘器。随着国家对水泥工业的环保要求越来越严,尤其是水泥工业新的排放标准的贯彻实施。静电除尘器要达到新排放标准的要求,必须解决微细粉尘的捕集。     

煤粉制备系统电收尘器改为袋收尘器的实践

酒钢（集团）宏达建材有限责任公司原有700t/d窑外分解熟料生产线配备了一台中2．2m×4．4m风扫式钢球煤磨,其煤粉制备系统配用一台三电场收尘器,其设计排放浓度≤150mg／Nm^3,这完全与现行排放标准不符,并且经过多年的运转,设备损坏和老化严重,电收尘器的排放严重超标,尤其是当生产不稳定时,经常出现冒黑烟的现象。     

Electrolytes: From a Thorn Comes a Rose,and from a Rose,a Thorn

In this article we take a stroll through the metaphorical rose garden, part of the flower garden, that is electrochemical storage systems. We take a closer look at batteries as the center‐pieces – the roses – and especially at the system component of batteries, the electrolyte and its development, throughout history. Just as a rose can only develop its unique beauty when taken good care of and provided with clean water and suitable nutrients, a battery cell cannot function without its electrolyte; the seemingly trivial component that has to juggle a multitude of requirements in order to make batteries truly bloom.     

Extraction into a flow of a fluid with a velocity gradient

Unsteady extraction from a system of semi-infinite capillaries to the flow of a fluid with a linear velocity gradient is studied. An assumption that the diffusion in the flow is a quasi-steady-state process is taken to obtain a linear equation for the local mass flux from the pore space, which involves fractional derivatives with respect to time and flow coordinate. Limiting solutions for the total diffusion flux at small and large times that cover the entire time interval are found.     

Propagation of a burning front over a condensed material from a focus

Measured propagation speeds are given for the combustion front in a blind gap in a condensed substance, which are related to gap height and mean pressure. The front may propagate monotonically, which is characteristic of relatively high pressures and wide gaps, or as a result of additional burning foci arising at a certain distance from the main front. At low pressures and particularly with small gap heights, the front propagates in an unstable fashion over the surface.Moscow. Translated from Fizika Goreniya i Vzryva, Vol. 28, No. 4, pp. 49–53, July–August, 1992.     

Mesomorphic transitions in a mixture of a flexible and a semi-rigid polymer

Phase studies on a mixture of two polymers are presented, one of which is mesomorphic. We have systematically examined the influence of the molecular weight of the flexible polymer (including the oligomers) and of the semi-flexible polymer. In addition to the effect of the molecular weight, specific interactions are important for compatibility and formation of a homogeneous mesomorphic phase. The nature of this phase is demonstrated to be cholesteric and the pitch is determined.     

When is a Beam a Plate?

Formulas associated with simple beam or plate theories are used extensively in structural design, to determine You's modulus, and to determine fracture strength of brittle nonmetallic materials. The question may arise as to whether the proper ratio of beam-width-to-beam-depth is such that the bent structural element can be considered as a beam and, if not, what is the correction factor that should be used with the simple beam formula. These questions are answered for a range of structural metallic and brittle nonmetallic materials.     

Laminar flow deformation of a droplet adhering to a wall in a channel

We study the deformation of oil droplets of varying viscosity adhering to a solid, rigid wall in a rectangular channel induced by a pressure-driven, laminar flow of water. Our experimental investigation involves the systematic study of the effects of initial droplet volume, flow rate and viscosity ratio on the various modes of droplet motion and deformation; this is performed via direct visualisation of the flow in a glass cell using a high-speed camera. Our results are used to construct flow maps that delineate the critical conditions for droplet ‘sliding’, ‘crawling’ and detachment from the channel wall as a function of system parameters. Comparisons of our experimental results with numerical predictions obtained using a procedure based on the diffuse-interface method yield reasonably good agreement for certain flow regimes.     

Growth of a Bonelike Apatite Layer on a Substrate by a Biomimetic Process

A dense and uniform bonelike apatite layer was formed on a substrate by the following biomimetic method. The substrate was first placed on granular particles of CaO, SiO₂-based glass soaked in a simulated body fluid (SBF) with ion concentrations nearly equal to those of human blood plasma and then soaked in another fluid highly supersaturated with respect to the apatite. The thickness of the apatite layer increased in proportion to the soaking time in the second solution. The rate of increase in the thickness of the apatite layer increased from 0.5 to 7.0 μm/day with increasing temperature of the second solution from 10° to 60°C, increased from 0.15 to 1.7 μm/day with increasing ion concentrations of the second solution from 0.2 to 1.5 times those of the SBF, and doubled by shaking the second solution. These results indicate that the growth of the apatite layer is controlled by mass transport across the interface between the crystal and the fluid.