300MW机组循环水系统改造

循环水系统是火力发电厂的重要辅机系统,也是厂用电的消耗大户,其耗电量约占机组发电总量的1%~1.5%[1]。为保证凝汽器冷却需求,循环水泵容量一般都具有较大的裕度。为了合理利用循环水泵的出力,节能降耗,三河电厂通过对设备和控制逻辑的改进,实现了循环水系统的母管制运行。改造后的运行实践证明,循环水母管制运行降低了辅机能耗,兼顾了机组的安全,具有一定的优越性。     

重质糠醛精制装置循环水系统的优化

针对重质糠醛精制装置循环水冷却器的结构特性和生产中环水冷却器管束结垢等问题,依据炼油分部对水冷却器防止管束腐蚀及结垢的最低流速要求,核算出该装置的最小用水量和相应水冷器的阀门开度,对该装置的循环水的使用提出优化措施,在一定的程度上解决循环水引起水冷却器管束结垢等问题。     

PLC与变频器在工业循环水系统中的应用

针对工业循环水处理系统的控制要求,利用PLC、变频器和三菱的其他工控器件对工业循环水处理系统进行自动化改造,采用PID策略对系统的各种模拟量进行实时控制,实现了工业循环水处理系统的优化控制、优化运行和优化管理,能适应大多数工业水循环处理需求,具有广泛的应用价值.     

浅谈火力发电厂循环水泵电机系统节电

根据我国火力发电厂循环水泵电机系统节约用电的现状,结合实例有针对性地对大型火力发电厂节约循环水泵电机系统用电的设计方案进行优化,从而提高火力发电厂建设运行期间的综合经济效益.     

高速线材轧钢生产线浊循环水的净化研究

对于高速线材轧钢生产线的浊循环水的净化来说,几种水处理剂的净化效果各异。研究表明,使用改性OBT处理循环水,当用量为0.008mg/L时,水中悬浮物和油的含量都达到设计指标;与传统的水处理剂相比,其具有高效、无毒的优点。     

建立校园循环水系统的可行性分析

研究了人员集中活动的校园在循环水使用方面的实践和探索,包括实例分析、资金预测和工况设计等具体细节.     

空压站循环水系统扩能改造

中心空压站淘汰6台活塞式空压机,更新为4台ZH7000-6-8型离心式空压机和2台GA250W-7.5型螺杆式空压机,新设备较老设备最大需循环水量增加约3倍,原循环水系统的供水设备、供水管道、储水能力均不能满足新设备的需求,必须进行扩能改造才能保证更新后设备正常运行。若不扩能需采用自来水直排冷却方式对更换后空压机设备进行冷却降温,才能保证更换后空压机设备的运行,采用自来水直排冷却方式,每年将白白扔掉自来水39.6万吨,水费213.84万元,而且造成水资源的极大浪费。所以无论从经济效益还是社会效益考量,现有循环水系统扩能改造势在必行。     

汽轮机低真空运行循环水供热改造技术研究

汽轮机低真空运行时,从锅炉获得热量的过热蒸汽,汽机在纯凝汽式运行时,只能利用这部分热量的27%左右,而近70%的热量由于循环水带走。经过循环水供热改造技术,可大量节约能源,经济效益十分可观。     

热电厂锅炉冲灰除渣循环水控制系统设计与应用

针对锅炉冲灰除渣循环水处理系统的生产工艺,分析了控制系统的技术特点,构建了基于PLC技术的控制系统设计方案;根据冲渣循环水pH值变化和波动特点,提出了基于模糊PID技术的控制方案;对系统传感器的配置、检测点的位置和取源部件的安装方式进行了详细阐述,并在仿真分析的基础上,将其投入实际控制运行,达到了较好生产使用效果。     

火电厂循环水钢管的程序计算

利用程序对循环水钢管进行稳定性计算、刚度计算、强度计算,不但克服了手工计算繁琐、容易出错等缺点,而且更能适应未来大机组发展的需要,具有很好的应用前景。     

给水过滤器反冲洗水浑浊特性的测定与分析

采用光学浊度仪对气浮过滤池滤料反冲洗水浊度进行实测,得到了整个滤池各滤格反冲洗水浊度的实验数据,对实验数据进行分析,绘出了反冲洗水浊度随时间变化的基本规律曲线.通过对实验数据和浊度变化曲线分析,获得了过滤池正常运行时反冲洗水的最高浊度、最低浊度及其浊度随时间变化的基本规律,同时弄清了出现最高浊度和最低浊度的滤格在滤池中所处的位置,进一步掌握了气浮过滤池运行过程中的过滤特性和反冲洗水的浊度变化情况,为反冲洗水回用方案的进一步研究提供了可靠的试验数据.     

多层钢毛滤料直接过滤处理低浊度含藻水的试验研究

针对地表水富营养化问题,采用多层钢毛滤料对低浊度含藻水进行了直接过滤的试验研究。通过改变滤速、混凝剂种类、混凝剂投加量,设计正交试验,得出多层钢毛过滤处理低浊度含藻水的最佳工艺参数。试验证明,多层钢毛滤料对低浊度含藻水有着非常好的过滤效果。     

Effect of a biological activated carbon filter on particle counts

Due to the importance of biological safety in drinking water quality and the disadvantages which exist in traditional methods of detecting typical microorganisms such as Cryptosporidium and Giardia, it is necessary to develop an alternative. Particle counts is a qualitative measurement of the amount of dissolved solids in water. The removal rate of particle counts was previously used as an indicator of the effectiveness of a biological activated carbon （BAC） filter in removing Cryptosporidium and Giardia. The particle counts in a BAC filter effluent over one operational period and the effects of BAC filter construction and operational parameters were investigated with a 10 m^3/h pilot plant. The results indicated that the maximum particle count in backwash remnant water was as high as 1296 count/ml and it needed about 1.5 h to reduce from the maximum to less than 50 count/ml. During the standard filtration period, particle counts stay constant at less than 50 count/ml for 5 d except when influenced by sand filter backwash remnant water. The removal rates of particle counts in the BAC filter are related to characteristics of the carbon. For example, a columned carbon and a sand bed removed 33.3% and 8.5% of particles, respectively, while the particle counts in effluent from a cracked BAC filter was higher than that of the influent. There is no significant difference among particle removal rates with different filtration rates. High post-ozone dosage （〉2 mg/L） plays an important role in particle count removal; when the dosage was 3 mg/L, the removal rates by carbon layers and sand beds decreased by 17.5% and increased by 9.5%, respectively, compared with a 2 mg/L dosage.     

CIC抽取滤波器的研究和设计

介绍了一种多采样率CIC抽取滤波器.研究了滤波器的原理,重点分析了设计过程中滤波器的误差.在此基础上,用一个滤波器的设计实例验证了滤波器的误差理论,并验证了CIC抽取滤波器通过采样速率变换因子R可降低滤波器的工作频率.结果表明,利用软件控制R可实现多采样率.     

Design of Maximally Flat FIR Filters Based on Explicit Formulas Combined with Optimization

A maximally flat FIR filter design method based on explicit formulas combined with simulated annealing and random search was presented. Utilizing the explicit formulas to calculate the ini- tial values, the firate-word-length FIR filter design problem was converted into optimization of the filter coefficients, An optimization method combined with local discrete random search and simulated annealing was proposed, with the result of optimum solution in the sense of Chebyshev approximation. The proposed method can simplify the design process of FIR filter and reduce the calculation burden. The simulation result indicates that the proposed method is superior to the traditional round off method and can reduce the value of the objective function to 41%～74%.     

Using chloramine as a coagulant aid in enhancing coagulation of Yellow River water in China

Considering that contaminated raw water mostly contains high Ammonia-N and a majority of water treatment plants use prechlorination process in China,efficiency of chloramines as a coagulant aid in enhancing coagulation was investigated by Jar stirring and pilot-scale tests,using Yellow River water containing high concentration of natural organic matters (NOM) and bromide in winter. The jar tests results showed that,compared with no preoxidation,preformed chloramine apparently decreased the turbidity of settled and filtered water with low dosage (2.0 mg/L),and the aid-coagulation efficiency was further enhanced with the increase of chlorine (Cl2) to Ammonia-N (N) ratio. Pilot-scale studies indicated that,in comparison to the case without pre-oxidation,the turbidity removal efficiency of flotation and filtration effluent water was significantly improved,the particle counts of filtered water were decreased 63.4%,the average rate of filter head loss was reduced 18.2%,and filter run time was prolonged 15.7%. Therefore,chloramine preoxidation may substantially enhance the particle separation efficiency.     

用动态旋叶压滤机过滤稀薄细颗粒悬浮液

介绍生产现场应用动态旋叶压滤机过滤含微量颗粒悬浮液的试验结果，分析了系统配置及操作压力等生产条件的影响及处理方法     

四步混凝法处理油田回注水的研究

实验采用四步混凝法探讨油田回注水处理剂及其工艺流程。结果表明该水处理工艺简单,水处理剂成本低,流程改动少。处理后水中的悬浮固体、总铁和含油量分别达到2.0mg/L、0.43mg/L和1.4mg/L;硫酸盐还原菌和腐生菌均为102个/mL;浊度降到0.2Ntu;平均腐蚀率降到0.037mm/a;处理后水符合油田回注水水质标准,并且水质稳定。     

三次样条插值卡尔曼滤波分光光度法同时测定NO_3~-和NO_2~-的研究

本文提出三次样条插值卡尔曼滤波分光光度法用于多组分同时测定，本法能减少实验工作量。对合成样中的ＮＯ－３和ＮＯ－２测定结果表明，此方法对不具自动扫描功能的分光光度计是有效的，且结果令人满意     

导弹控制系统设计中的弹体弹性振动问题及陷波滤波器设计

应用陷波滤波器消除了弹体弹性振动固有频率信号对控制系统的影响,给出了陷波滤波器的设计方法,仿真结果证明了设计方法的正确性.