膜吸收法烟气同时脱硫脱硝试验研究

采用自行研制的新型错流式气-液膜接触器,以NaClO2海水溶液为吸收液,分别以NaHCO3/Ca(OH)2/Ca(ClO)2为添加剂,对电厂燃煤烟气开展膜吸收法烟气同时脱硫脱硝现场试验研究.考察了吸收液流量、浓度、活化时间、初始pH以及烟气流量、SO2浓度等因素对脱硫脱硝效果的影响.试验表明:增大吸收液流量和浓度,NOx和SO2脱除率升高;延长吸收液活化时间,增大烟气流量,脱硫脱硝率略有降低;吸收液初始pH升高,脱硫率几乎不变,而脱硝率却略有降低;随着SO2浓度增大,脱硝率出现极值点;另外,添加剂NaHCO3/Ca(OH)2/Ca(ClO)2对NaClO2氧化吸收NOx和SO2均有增强作用.采用膜气体吸收技术,可实现烟气同时脱硫脱硝,具有一定应用潜力.     

镁法烟气脱硫工艺烟尘浓度超标原因分析及控制措施研究

针对镁法烟气脱硫工艺在实际使用中常常出现脱硫后烟尘浓度高于脱硫前甚至超标的情况,通过以两台130t/h热电锅炉脱硫后烟尘实际测试,分析滤筒中烟尘电导率(EC)、镁离子和硫酸根离子浓度.结果表明:随着烟气中烟尘浓度的增加,EC、SO42-和Mg2+浓度均相应增加,且呈显著正相关关系,证明脱硫液随烟气迁移是脱硫后烟尘浓度增加的重要原因之一.     

燃煤电厂脱硫技术机理分析

SO2的排放直接影响到环境,危害人类的健康,而燃煤电厂的SO2排放量一直是我国大气污染的主要来源,因此,对燃煤电厂进行脱硫意义重大。本文首先对燃煤电厂烟气脱硫的现状进行了概述,对燃煤电厂脱硫技术尤其是石灰石-石膏湿法脱硫技术进行了详细探讨,对烟气脱硫技术发展中应注意的问题提出了一些看法,最后对烟气脱硫技术的发展前景进行了展望。     

浅谈两段式煤气发生炉脱硫方法

大气中的SO2与降水溶合形成酸雨，严重破坏生态环境和危害人体健康，加大癌症发病率，甚至影响人类基因造成遗传疾病。削减二氧化硫的排放量，控制大气二氧化硫污染、保护大气环境质量，是目前及未来相当长时间内我国环境保护的重课题之一。由于公司使用的是烟煤制作煤气供焙烧炉和熔盐炉使用，为有效减少烟气中SO2排放量，公司采用在煤气出口处加装脱硫装置，使用湿法脱硫与干法脱硫装置相结合的方法，脱除煤气中H2S从而有效减少烟气中SO2排放量。     

烧结烟气氨法脱硫控制系统应用实例

我国钢铁冶炼工序中烧结工艺产生的烟气含有大量二氧化硫,是大气的主要污染源。烧结烟气的治理成为钢铁工业SO2减排的重点。近年,国家环保对烧结机烟气排放要求也日益严格,烧结烟气脱硫是钢铁业减排SO2的主要途径。氨法脱硫工艺是一种全新的烧结脱硫工艺,它不仅能有效地脱除烟气中的二氧化硫,而且符合国家节能减排的要求。而自动控制系统在氨法脱硫工艺中起到举足轻重的作用。接下来,本文将对烧结烟气氨法脱硫控制系统进行详细分析。     

海水烟气脱硫膜吸收单元及工艺研究

以海水作为吸收剂,采用自行研制的中空纤维管式膜接触器作为吸收单元,进行膜吸收法海水烟气脱硫过程模拟试验研究.考察膜接触器结构、膜填充密度、膜吸收单元工艺方式、模拟烟气SO2浓度、温度、气液流量等因素对脱硫效率的影响.结果表明,提高烟气温度、海水流量、膜接触器内气液分布均匀程度、气液相有效接触面积、增加膜吸收级数,均有利于提高脱硫率;烟气流量及SO2浓度的增大不利于SO2的脱除;烟气流经管程的气液流程方式利于提高脱硫率,但是气阻大,进气压力高,工程化应用难以实现.提高膜材料传质特性和优化设计膜接触器结构是提高膜吸收法烟气脱硫效率的根本途径.     

NID技术在立式旋风炉应用中存在的问题及解决方案

火力发电厂中,煤炭经过锅炉燃烧后,排出的烟气中含有大量的SO2,这部分SO2一经排放到空气中,会对环境造成严重的危害。随着社会的环保的意识的不断加强,火力发电厂的烟气脱硫工作就显得越发重要。烟气脱硫方法可分为干法,湿法及半干法脱硫,这几种脱硫方法在实际应用中各有特点和弊端。那么如何根据火力发电厂的实际情况考虑,选择一种适合的烟气脱硫方法,并且在实际应用中,通过不断地实践和摸索,及时的的发现脱硫技术和设备存在的问题并加以解决,无疑是做好烟气脱硫工作的保障。     

浅析中小型燃烧烟气脱硫技术及工艺

我国是一个燃煤大国,随着经济的快速发展煤炭消耗的不断增大,二氧化硫的大量排放致使环境污染不断加大,温室效应逐年严重,区域性大面积酸雨不断发生,如何降低二氧化硫排放量,控制二氧化硫对环境的污染、保护大气环境成为社会环境保护的重要课题。烟气脱硫是指从管道烟气或其他工业废气中除去硫氧化物SO2和SO3的相关技术和工艺,本文对几种典型的烟气脱硫技术和工艺进行了浅析。     

关于脱硫技术的可行性分析

随着环保力度的加强，保护环境、控制和降低燃煤硫污染的任务相当艰巨而迫在眉睫了。一个相当有效的控制方法是电厂烟气脱硫。我公司3台35t／h锅炉运行至今均未有脱硫装置，SO2排放量在420mg／m3左右，在当前的大形势下，务必需要安装脱硫装置。     

循环流化床锅炉烟气脱硫技术应用探析

加大力度控制燃煤电厂SO2已经成为法当务之急。本文阐明了国内外脱硫技术发展现状,阐述了国内外技术发展趋势,并对循环流化床锅炉烟气脱硫技术进行实例分析。     

Insertion of triangulated surfaces into a meccano tetrahedral discretization by means of mesh refinement and optimization procedures

In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

Flow calorimeter for enthalpy increment measurements on condensed gases

A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.     

From Industry 4.0 to Research 4.0. Development of High Performance Fibers in the Light of Digitization

We associate a variety of innovations with the term ＂Industry 4.0＂. The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di...     

Refrigerators Enter a New Era of Health Preservation Frestech initiates the establishment of China's first standard for household sterilization refrigerators

On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.……     

Roman iron and steel: A review

ABSTRACT

The production of ferrous metal increased during the Roman Late Republican period, Principate and Empire. The direct bloomery process was used to extract the metal from its ores using slag-tapping and slag-pit furnaces. The fuel was charcoal and an air blast was introduced by bellows-operated tuyères. Iron formed as a bloom, often as a spongy mass of metal, which contained impurities from the smelting process, including unreacted ore, fuel, slag and fragments from the furnace walls, while the metal was often inhomogeneous with varied carbon contents. Blooms were either smithed directly into bars or ingots or they were broken up, which also allowed the removal of gross impurities and a selection of pieces with similar properties to be made. These could then be forge-welded together and formed into characteristically shaped ingots. Making steel in the furnace seems to have been achieved: it depended on the ore and the furnace and conditions within it. Surface carburization was also carried out. Iron and steel were used extensively in construction and for tools and weapons. Fire welding was often used to add pieces of steel to make the edges of tools and weapons, which could be heat-treated by quenching to harden them.     

Optimum-Simulation von Ernteprozessen

Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.     

A study of centrifugal cast high boron high speed steel

In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M₂(B,C), (W,Mo)₂(B,C), M₃(B,C), M₂₃(B,C)₆ type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm². The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K₁ mill housing of bar mill.     

Thixotropy of Systems with Shear Thinning and Plastic Flow Behavior

The definition of the thixotropy is a decrease in viscosity with time in shear and a subsequent recovery of viscosity after the shear deformation is removed.We ...