硫化供水水泵负荷平衡控制

为控制硫化供水压力波动范围．开始采用2台同型号水泵单独变频控制方式。实验后，在某种情况下易造成1台水泵汽化。后改用负荷平衡控制方案，使系统有自动、手动、半自动3种运行方式，备用泵可以自动根据负荷启停，也可手动启停。经过年多的运行．压力控制理想．减轻了工人劳动强度。并对系统操作中应注意的几个问题进行了说明。     

变频调速在恒压供水系统的应用

本文以达拉特发电厂水场工业供水系统变频改造为例,介绍了一种替代压力水罐供水的基于PLC和变频调速器的恒压供水系统的结构和工作原理。该系统采用变频调速方式自动完成泵组软启动并自动调节水泵电机转速,使水压平稳过渡。通过PLC控制系统实现自动加、减水泵,并采用"先启先停"的控制方式实现水泵无冲击切换。当变频器故障或系统断电时,系统可切换至手动运行方式,保证不间断供水。采用软、硬件备用和钟控方式,使各水泵进行轮休,延长了设备的使用寿命。     

变频调速在神华准能电厂的应用

通过介绍变频调速的方法和节能原理,分析了风机、水泵等的节能情况,应用变频调速技术,通过对辅机系统进行改造,能够提高发电厂经济效益,从而提高火力发电厂的竞争力。     

高压变频调速系统在水泥回转窑尾风机中的应用

本文介绍了Harsvert-VA 06/130型高压变频调速系统在某水泥企业2000t/d水泥线回转窑尾风机电动机变频调速改造中的应用,阐述了高压变频调速系统的原理及改造后的运行情况。系统改造运行后节能效果明显,调速性能得到提高。     

加压泵房水泵变频器改造及应用

应用变频改造技术对加压泵房水泵进行改造.介绍变频调速恒压供水控制系统压力控制原理、水泵变频器改造及实际应用效果.     

给水泵液力偶合器在工作中的问题分析

我厂3台200MW机组的锅炉给水系统给水均由给水泵供给。3台机的每台机组的给水泵设置为2台调速给水泵,3台机组的锅炉给水由给水泵定期轮换运行给水。由于液力偶合器是调速给水泵的主要设备,所以液力偶合器的运转稳定对给水泵的节能和安全运行起着关键作用。     

风机,水泵变频调速——节能技改的有效途径

介绍了交流变频调技术的主要特点与风机，水泵调速节能的原理和计算方法，结合实例叙述了对长期变工况运行的风机，水泵进行变频改造的必要性和显著节能降耗效益，提出了开展变频改造工作的应注意事项。     

无极绳绞车变频调速控制系统的设计

针对无极绳运行绞车在实际运行过程中存在启停阶段对系统冲击力大、掉道事故发生等现象,本文在对无极绳绞车组成及现状研究的基础上,提出将全液压调速+变频调速相结合的调速方式,其中全液压调速采用模糊控制策略,变频调速采用PID控制器,最后经过反复试验确定各个控制策略的系数。     

基于耦合补偿的矢量变频驱动带式输送机的功率平衡控制策略

针对矢量变频驱动的带式输送机在运行过程中出现的功率不平衡问题,对三相异步电动机的变频调速过程进行了系统的理论分析,提出了一种基于耦合补偿的电机功率平衡控制策略。建立了双电机矢量变频驱动的功率平衡控制系统,同时依据系统模型利用Matlab平台进行了仿真测试。结果表明:无论是在系统进入稳态或者是在启停、调速、负载变化的动态过程中,耦合补偿控制均能够保证电机之间的输出功率平均分配,具有较好的抗干扰性和同步性。     

变频技术在水厂泵房电机上的应用

分析了巴陵石化有限公司对供水车间7#供水泵的低压电机进行变频改造的原因，介绍了实现变频调速控制的方法。实施变频改造后，运行效果安全稳定，取得了较明显的经济效益和社会效益。     

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