中压氨气提法尿素生产技术总结

一、方案和流程我厂中型水溶液全循环法尿素生产装置设计蒸汽用量为32.7t/h,尿素产量为17.2t/h(冬季),单耗为1.9t/t.ur,蒸气耗量高。从设备耗汽量看出,一段分解加热器耗汽量最多,约占整个尿素生产系统用汽量的     

汽封汽平衡管道改造方案

因汽轮机组前、后汽封体、调节汽门、自动主汽门、汽动油泵、抽汽逆止阀各部件磨损,间隙变大,漏汽量增大,汽封加热器不能将以上各处漏汽全部抽入,容易漏入大气,造成蒸汽浪费。经改造后,机组汽平衡母管压力降低,进入汽封加热器蒸汽量减少,一方面有利于机组稳定运行;另一方面蒸汽进入换热器,凝结水回收,可降低蒸汽浪费,节约能源,降本增效。     

湿蒸汽V锥测量装置的标定及其数据分析

注汽管线内的高温高压湿蒸汽为多相流体,因此给蒸汽干度和蒸汽质量流量的在线测量带来很大的困难。为了准确计量蒸汽的量,提高能量的利用率,开展注汽管线内的蒸汽两相流计量意义重大。V锥"体积变化"式注汽锅炉蒸汽流量和干度在线测量原理,解决了在线干度的测量与控制问题。因此V锥在线测量系统精确标定十分重要。     

发挥自备热电厂现有设备出力 增设6MW纯凝机组的技术可行性分析

从锅炉的出力、汽轮机的耗汽量、外供汽量,循环水量的配置上论述了增加6 MW纯凝机组的技术可行性。     

减负荷时汽轮机排汽温度上涨原因分析

对泸天化绿源醇业公司抽汽凝汽式轮机在减负荷时出现凝汽段末级排汽温度和表冷器的真空度下降等问题进行分析,认为主要是由于进入凝汽段的蒸汽量偏多造成。并提出判断汽轮机蒸汽耗量是否偏多的方法,为生产实践提供理论依据。     

金桥热电厂过热汽温控制系统分析及优化

通过增加燃烧量前馈、主汽压力前馈、摆动燃烧器前馈和4阶惯性减温器后汽温前馈,克服了过热蒸汽温度因机组负荷变化、燃料量变化、炉膛火焰中心变化等因素造成的扰动,解决了过热蒸汽温度系统原来存在的问题,取得了良好的控制特性。     

延迟焦化冷焦过程节能减排改造

焦化装置焦炭塔大吹汽用1．0MPa蒸汽对生焦老塔进行吹汽,由于用汽量大,对热能冲击较大。．还有冷焦水消耗量与净化水的量不平衡,净化水COD较高,污水处理场处理困难,剩余大量净化水。所以提出利用汽提净化水代替1．0MPa蒸汽大吹汽工艺。通过装置实际应用,证明了此工艺可减少蒸汽耗量．降低装置能耗以及减少污水排放量,提高经济效益。     

电解液浓度与蒸发工序蒸汽定额

氯碱生产中电解碱蒸发汽耗高仍是氯碱生产中的一大课题,影响汽耗高的因素较多,其中电解液浓度波动大,蒸发系统加水无计量,余热利用不充分,热损失大等都直接影响汽耗。为便于分析汽耗高的原因,首先按三效三体二段蒸发工艺流程计算一下蒸发不同浓度电解液汽耗(不包括系统加水)并与实际蒸汽定额进行对比,找出影响汽耗高的主要因素,详细计算分述如下:     

筒式电容测试注汽井干度算法机理与实现

为研究热采注汽井沿程蒸汽参数的变化规律,采用筒式电容方法精密测量注汽井蒸汽热力学参数,分析注汽井温度、压力和蒸汽干度随井深的变化特征。构建注汽井蒸汽干度测量模型,对蒸汽干度测量模型进行数值反演,考查蒸汽干度随介电常数的变化规律,揭示了干度值随井深的增大逐渐减小。     

双进气AQC锅炉余热发电系统特点分析*

为提高汽机主进汽温度,水泥窑头篦冷机余热发电抽风可采用多点取风以获得更高的取风温度,提高机组热经济性。本文以某海外项目设计资料为基准,从发电功率、汽耗、热耗等多方面分析了双进气AQC锅炉余热发电系统,较之于传统单进气AQC锅炉余热发电系统的特点,结果表明:双进气AQC锅炉余热发电系统可获得更高的主汽温度,从而显著提高机组发电功率,降低机组汽耗、热耗,是优化水泥窑余热发电系统的又一重要措施。     

乙烯酮(双乙烯酮)下游产品废水的治理技术

乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。     

A study of miscibility of blends of polybutadienes of varying microstructure

The miscibility of various amorphous polybutadienes with mixed microstructures of 1,4 addition units (cis, 1,4 and trans 1,4) and 1,2 addition units have been investigated. The studies here involved optical transparency, differential scanning calorimetry, and small angle light scattering. It was found that a 90 percent (cis) 1, 4 addition polybutadiene was immiscible with high (91 percent) 1,2 addition polybutadiene. Reduction of the 1,2 content to 71 percent induced an upper critical solution temperature (UCST) with the cis 1,4 polymer. Polybutadienes with 50 percent and 10 percent 1,2 contents were miscible above the crystalline melting temperature of the cis 1,4 polybutadiene. Immiscibility of the 91 percent 1,2 addition polymer was also found with a 10 percent 1,2 polybutadiene. The latter polymer also exhibits an UCST with the 71 percent 1,2 polymer. The results are used to interpret the characteristics of blends of polybutadienes of varying microstructure.     

几种乙炔加压设备性能的比较

阐述并比较了几种加压设备在乙炔加压清净过程中的性能和特点。     

粉煤灰中烧失量检测的不确定度分析

以F类粉煤灰为例,详细介绍了测定粉煤灰中烧失量的步骤、计算数学模型、影响测量不确定度的因素以及各项测量不确定度分量评定,人员、设备、材料、方法、环境都是影响测量不确定的因素。     

生物油的成分分析及物性测定

以添加FeCl2的ZnCl2-KCl混合熔盐裂解纤维素和秸秆,制得生物油。采用傅立叶变换红外光谱法和气相色谱-质谱法分析生物油的成分。结果表明,生物油中成分复杂,含有氧元素、多种有机化合物,主要包括酮类、醛类、酚类及羧酸类等。测定了20～80℃生物油的密度和粘度,发现生物油的密度与温度呈较好线性关系,而生物油的粘度均大于水的粘度,且不同熔盐体系对秸秆生物油的粘度无较大影响。     

Effect of degree of deacetylation of chitosan on the kinetics of ultrasonic degradation of chitosan

The objective of the study was to explore the effect of the degree of deacetylation (DD) of the chitosan used on the degradation rate and rate constant during ultrasonic degradation. Chitin was extracted from red shrimp process waste. Four different DD chitosans were prepared from chitin by alkali deacetylation. Those chitosans were degraded by ultrasonic radiation to different molecular weights. Changes of the molecular weight were determined by light scattering, and data of molecular weight changes were used to calculate the degradation rate and rate constant. The results were as follows: The molecular weight of chitosans decreased with an increasing ultrasonication time. The curves of the molecular weight versus the ultrasonication time were broken at 1‐h treatment. The degradation rate and rate constant of sonolysis decreased with an increasing ultrasonication time. This may be because the chances of being attacked by the cavitation energy increased with an increasing molecular weight species and may be because smaller molecular weight species have shorter relaxation times and, thus, can alleviate the sonication stress easier. However, the degradation rate and rate constant of sonolysis increased with an increasing DD of the chitosan used. This may be because the flexibilitier molecules of higher DD chitosans are more susceptible to the shear force of elongation flow generated by the cavitation field or due to the bond energy difference of acetamido and β‐1,4‐glucoside linkage or hydrogen bonds. Breakage of the β‐1,4‐glucoside linkage will result in lower molecular weight and an increasing reaction rate and rate constant. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3526–3531, 2003     

分解炉扩径的技术改造

我厂3号回转窑(Φ4m×60m)生产线在1996年年底由SP窑(产量912t/d)改为NSP窑(产量1320t/d),预分解系统为四级旋风预热器带离线式分解炉