尿素装置蒸汽消耗控制探讨

大型尿素生产装置中,所用蒸汽除满足工艺换热要求外,还用于驱动二氧化碳压缩机汽轮机,蒸汽用量较大,对尿素成本的影响不容小觑。本文以二氧化碳汽提法尿素装置为例,探讨控制蒸汽消耗的措施。     

尿素高压洗涤器3203-C上封头修复

介绍了3203—C上封头的修复程序，重要环节的质量控制。     

尿素高压洗涤器防爆空间衬里泄漏原因及修复

认为金陵石公司化肥厂高压洗涤器E2203防爆空间衬里泄漏原因是焊缝角变形而引起的应力疲劳。通过焊接实验对衬里的可修复性进行分析，总结修复E2203防爆空间衬里的措施。     

尿素高压洗涤器上封头换衬技术要点及探讨

总结尿素高压洗涤器上封头更换衬里的要点及施工验收情况,对松衬间隙问题进行探讨,并提出了解决问题的建议。     

尿素流程高压洗涤器的模拟计算及分析

基于严格的热力学机理模型 ,对尿素工艺流程中高压洗涤器中下两段分别建立了平衡级模型 ,通过迭代求解两个模块 ,使连接两模块的中间流股收敛 ,完成了对整个洗涤器的模拟计算 ,计算结果同设计值吻合较好。针对该体系的强非理想性及数学模型的强非线性 ,提出可行的求解策略 ,算法稳定且收敛性较好。该研究为改造、优化工艺操作及单元设备结构提供了理论依据     

尿素高压系统压力的控制

分析尿素生产中影响高压系统压力的主要原因,提出了解决问题的对策。     

二氧化碳气提尿素工艺高压洗涤器防爆问题探讨

传统尿素产业,包括20世纪50年代末创建的水溶液全循环法中小型尿素装置、七八十年代引进的CO2汽提法和NH3汽提法等大型尿素装置,尾气防爆问题一直是尿素行业关注的棘手课题。     

高压洗涤器气相带液原因分析及处理措施

<正>兖矿鲁南化工有限公司尿素车间原有2套水溶液全循环尿素生产装置,后经双结构改造,增加1套CO2汽提法尿素生产装置(3#尿素装置),于2007年6月投产试车。试车后,装置运行较稳定,但在高负荷生产后波动较大,造成高压系统超压严重、低压系统波动、操作难度大,无法控制系统操作指标,多次减负荷运行,严重影响系统的产量及安全运行。1高压洗涤器气相带液对各系统的影响(1)高压洗涤器气相带液对高压系统的影     

大颗粒尿素装置中尿素粉尘洗涤器(塔)开车总结

海德鲁型大颗粒尿素装置在国内已有数套投产。天津大学为其中 5个日产 10 0 0～ 2 30 0t的大型尿素工厂配备了尿素粉尘洗涤塔 ,塔径从6m～10m共计 8台。现对这些塔器开车和生产操作数据进行总结     

尿素高压液氨泵的技术改造

河北迁安化肥股份有限公司1972年7月建成,设计生产能力为合成氨6万t／a,尿素11万t／a,安装配套3W-2BA,高压液氨泵3台,2开1备。高压液氨泵为卧式三柱塞式,柱塞直径为φ85mm,共3根,柱塞行程240mm,往返次数105次／min,泵入口压力1．7MPa,出口压力20MPa,出口排液量24m^3／h;     

文丘里洗涤器压力损失的设计计算

对国内推荐使用的计算文丘里洗涤器压力损失两种方法进行了分析,并与本文所推导的理论模型的计算值进行了对比。结果表明,推导的理论模型的计算值与实验值吻合程度优于推荐使用的计算方法,可以作为文丘里洗涤器压力损失设计计算的理论依据。     

防止高锰酸钾蒸发器“跑液”的措施

着重介绍了高锰酸钾蒸发器在蒸发过程中发生“泡液”及为何防止“跑液”的办法。     

尿素装置中压吸收塔控制系统改造

大庆石化分公司化肥厂尿素装置中压吸收塔控制系统不稳定 ,经常造成尿素低压系统波动 ,使水解系统运行不正常 ,严重地制约着尿素装置的正常生产。中压吸收塔进料系统的给料泵采用高频给料泵 ,泵出口压力 0 .1 5ＭＰａ左右 ,给料管线为2 5 4ｍｍ管线 ,相对比较细 ,在系统运行时管线振动较大。进料流量涡街测量仪表 (ＦＴ30 6)安装在距泵出口 3ｍ左右的位置 ,如图 1 (ａ)所示。表体感觉振动较大 ,显示值忽高忽低。流量控制调节阀ＦＶ30 6(风开阀 )工作不正常 ,无法满足正常调节状态 ,在调节阀正常安装时 ,即使发出全关信号 ,调节阀仍保持一定…     

以尿液为氮源的料浆法复混肥料

尿素是现有高浓度固体氮肥之一,已成为国际上主要氮肥品种,也是我国氮肥发展的主要品种,在农业推广平衡施肥的政策下,单质化肥制成复混肥料为大势所趋,既方便农民使用,又能获得较好的增产效果,更有提高养分利用率和有利生态环境的好处。国外发达国家的农用肥料中,复混肥已占施用肥料的（60～80）%,而我国大致是15%左右,为此,提高施用肥料中复混肥料的比重和充分利用以尿素为氮源的复混肥料,为广大农业和化肥工业所重视。     

Experimental and Theoretical Investigation of Droplet Dispersion in Venturi Scrubbers with Axial Liquid Injection

Droplet dispersion in a Venturi scrubber with axial liquid injection was investigated both experimentally and theoretically. The main objective of this study was to develop a mathematical model to predict droplet dispersion in a Venturi scrubber with axial liquid injection. The effects of the Peclet number and droplet size distribution on droplet dispersion were studied using the developed model. Sampling of the droplets was carried out, isokinetically, in 16 positions at the end of the throat section. The experimental data were used to find the parameters of the developed model, such as the Peclet number. From the results of this study, it was found that the Peclet number was not constant across the cross section of the scrubber channel. In order to achieve a better agreement between the results of the model and the experimental data, it was required to consider Peclet number variations across the Venturi channel. It was also revealed that the parameter representing the width of the Rosin‐Rammler distribution of droplet size could not be considered constant and it was influenced significantly by the operating parameters such as liquid flow rate and gas velocity.     

Trickle Bed Wetting Factors From Pressure Drop And Liquid Holdup Measurements

In this work, solid-liquid wetting factors were determined from liquid holdup and pressure drop measurements according to the model proposed by Pironti et al. for different air-liquid systems: distilled water and CMC solutions at viscosity values of 3, 6, 9, and 12 mPa.s. The experiments were carried out at atmospheric conditions in a column of 10.2 cm internal diameter and 2 m high, packed with a cylindrical material. The superficial mass velocities varied from 0.67 to 18.6 kg/m 2 s for liquid flow and from 0.024 to 0.31 kg/m 2 s for gas flow. Under these operating conditions, regime of continuous gas flow was observed. The wetting factors obtained were in agreement with those reported by other methods, which allow us to confirm that the model used in this work is applicable to fluids of different properties at low gas velocities.     

Trickle Bed Wetting Factors From Pressure Drop And Liquid Holdup Measurements

In this work, solid-liquid wetting factors were determined from liquid holdup and pressure drop measurements according to the model proposed by Pironti et al. for different air-liquid systems: distilled water and CMC solutions at viscosity values of 3, 6, 9, and 12 mPa.s. The experiments were carried out at atmospheric conditions in a column of 10.2 cm internal diameter and 2 m high, packed with a cylindrical material. The superficial mass velocities varied from 0.67 to 18.6 kg/m 2 s for liquid flow and from 0.024 to 0.31 kg/m 2 s for gas flow. Under these operating conditions, regime of continuous gas flow was observed. The wetting factors obtained were in agreement with those reported by other methods, which allow us to confirm that the model used in this work is applicable to fluids of different properties at low gas velocities.     

Liquid Consumption of Wetted Wall Bioaerosol Sampling Cyclones: Characterization and Control

Advances in microfluidic, lab on chip, and other near-real-time biological identification technologies have driven the desire to concentrate bioaerosols into hydrosol sample volumes on the order of tens of microliters (μL). However, typical wet biological aerosol collector outputs are an order or two of magnitude above this goal. The ultimate success of bioaerosol collectors and biological identifiers requires an effective coupling at the macro-to-micro interface. Liquid collection performance was studied experimentally for a family of dynamically scaled wetted wall bioaerosol sampling cyclones (WWC's). Steady-state liquid collection rates and system response times were measured for a range of environmental conditions (temperatures from 10°C to 50°C and relative humidities from 10% to 90%), liquid input rates, and WWC airflow configurations. A critical liquid input rate parameter was discovered that collapsed all experimental data to self-similar empirical performance correlations. A system algorithm was then developed from empirical correlations to provide control over the liquid output rate and resulting concentration factor for a cyclone with an airflow rate of 100 L/min. Desired liquid output rates of 25 to 50 μL/min were maintained while sampling outdoor air over diurnal ranges of environmental conditions. These flow rates are associated with concentration factors on the order of 1,000,000 to 2,000,000 and liquid outputs that are a steady stream of 10 to 30 drops/min of 7 to 10 μL droplets. These developments should allow wetted wall cyclones to be effectively coupled to advanced biological identification systems.     

尿素界区高压系统调节阀技术改造

我厂尿素装置采用意大利斯纳姆氨气提尿素生产工艺。其生产特点是高温、高压、强腐蚀、易结晶。由于强烈的冲刷及腐蚀作用 ,时常出现调节阀损坏现象。特别是高压系统的调节阀 ,事故多、寿命短、处理过程复杂并且时间较长 ,严重威胁着尿素装置的长周期运行。多年来 ,我们针对不同的事故现象分别进行分析研究 ,找到一些解决问题的具体方法 ,并对部分调节阀进行实施 ,效果良好 ,为尿素装置的安全、稳定运行排除了障碍。1　尿素合成塔出口控制阀1 .1　故障分析HV - 0 92 0 3是尿素合成塔出口尿液的控制阀 ,为高压蝶阀 ,自开车以来 ,连续多次发…