中控操作岗位容易忽视的细节

<正>中控操作岗位是水泥企业的关键岗位之一,操作员不仅要在安全生产的前提下完成公司下达的各项生产任务,还要最大程度地给企业节约生产成本。笔者总结自身十年中控操作经验,通过案例说明一些中控操作容易忽视的细节,及其对生产和安全的影响。1安全培训的重要性笔者于2003年3月进入公司,经过公司、分厂和工段的各项培训后于3月底跟师傅倒班巡检生料磨,经过一段时间的学习掌握了一定的故障处理能力。某     

浅谈中控操作员必备的素质

中控室作为水泥生产线的机要部门,中控操作人员的素质有着举足轻重的影响。中控操作人员需加强责任心的培养,同时要有良好而稳定的心理素质。在操作中除知道怎么做,还需要知道为什么要这么做,必须弄明白操作的原理。对操作参数需要根据具体情况采取灵活策略,应多注意观察系统参数,及时准确地判断并处理问题。工作中需勤下现场检查,发现问题和解决问题。中控操作应追求降低系统能耗,对中控操作员的评价应着重于问题的解决能力和对问题的预见能力。     

一次生料磨饱磨造成的出磨斜槽堵塞的事故处理

中控操作是一个细心活、责任活、技术活,要低能耗高产量地实现"均衡稳定"生产的终极目标,离不开中控操作员优良的操作习惯、一流的操作技能、灵活有效的技术手段。     

DCS系统故障中控窑系统操作预案

我公司10000t／d生产线的DCS控制系统于2010年6月出现故障,最后造成停窑。本文介绍DCS出现故障时中控对窑系统的操作预案。     

《水泥中控操作员》即将出版

<正>由重庆电子工程职业学院建筑与材料工程系教授赵晓东主编的《水泥中控操作员》一书将于2014年春出版。该书比较详细地介绍了新型干法水泥企业的生产工艺流程、主要设备、热工仪表及自动控制、主要控制参数、正常开车及停车、紧急停车、正常操作控制、常见生产故障及处理等方面的知识技能。《水泥中控操作员》是继《水泥新型干法中控室操作手册》之后的又一本关于水泥生产中控操作方面的公开出版的书     

浅谈中控操作画面信号的设置

中控操作画面与信号的设置包括操作画面的绘制、趋势图的设定、报警参数的设置,及建立和加强必要的连锁关系等等。中控操作画面信号的设置是否合理和科学,关系到中控操作员对整个系统工况的正确判断和把握。因此要求中控操作画面形式和使用逻辑简洁明了,而且每一时刻、某一时段的运行状况和运行参数都需有详实的记录,便于查阅、对比和分析。     

循环水泵自动控制改造

我公司5 000 t/d生产线主要机械设备大多靠循环水来实现降温冷却,循环水泵房有两台额定流量300 m³/h、额定功率45 kW、扬程40 m的水泵。生产过程中1#泵运行,2#泵备用,现场有本地和远程转换开关,均可实现本地和远程控制。主管道上安装有流量计和压力表,岗位员工按时巡检查看,确保流量保持在240 m³/h以上,压力保持在0.25 MPa以上。若水泵跳停后在中控操作画面有故障报警信息,中控操作员发现信息后通知岗位员工巡检处理。     

不停窑处理篦冷机高温段故障的实践

2011年1月7日,我公司5 000t/d生产线在高温段篦床停机43min,窑系统没有止料停产的情况下,顺利完成了篦冷机高温段液压缸的更换。此次不止料处理故障中,中控操作的重点是不能将一段篦床压死,不能诱发其他事故,尽可能维持窑系统以较高的产量运转。     

水泥生产事故处理预案在中控操作中的实践

安全生产、文明生产事关劳动者的生命和健康,任何人都没有理由掉以轻心。由于生产过程中存在着可能发生突发性重大设备事故和工艺事故的危险,每个企业都应该尽早地建立事故应急处理预案,防止事故进一步扩大。特别是在新型干法水泥生产线的中控操作中,建立事故应急处理预案意义更加明显。因为中控是现代化水泥企业生产正常运营时的产、质量载体和责任者,履行着开停、运行监控和调整控制的职责;中控操作员相当于“大脑”。     

一起高压电机“自启动”故障的分析与处理

2020年6月10日上午10点,我公司电气人员处理水泥磨主电机油站不能中控开机故障时水泥磨突然启动运行,现场巡检人员发现磨机运行后立即联系中控,得知中控并未开启磨机,现场人员随即到磨机控制箱旁手动关停设备。此事故造成主电机油站、主减速机油站、磨头磨尾油站均未运行情况下磨机运行2 min,磨尾斜槽堵料,所幸因及时停机未造成设备损坏和人身事故。     

Modelling and optimisation of continuous catalytic regeneration process using bee colony algorithm

The continuous catalytic regeneration (CCR) reforming process optimisation leads to nonlinear programming with nonlinear quality constraints such as octane number and coke concentration on the catalytic particles. A typical CCR reforming process consists of four reactors with recycle. The reaction patterns and reactors have been mathematically modelled on a base of 12‐lumped kinetics reaction network derived from literature. The bee colony optimisation (BCO) algorithm is one of the most recent and efficient swarm intelligence‐based algorithms which simulates the foraging behaviour of honey bee colonies. The performance of the BCO algorithm in the process optimisation was compared with the genetic algorithm (GA). In the present work, BCO algorithm was used for optimising the CCR reforming process. The results show that the BCO algorithm reaches a better optimum point in a lower evaluation time and higher convergence rate with respect to the GA. © 2012 Canadian Society for Chemical Engineering     

Repetitive control of CATOFIN process

The CATOFIN process is a propane dehydrogenation process for production of propylene. It uses multiple adiabatic fixed-bed reactors where dehydrogenation and regeneration (decoking) are performed alternatively over roughly ten minutes of period for each operation. Taking advantage of the periodic operation, the present research concerns the development of a repetitive control method to improve the operation of the CATOFIN process. The controller is designed to perform feedback action during the regeneration cycle and to perform only state estimation during the dehydrogenation cycle. To improve the performance while overcoming the nonlinearity of the process, a linearized time-varying process was derived from a first-principle model and used for the controller design.     

基于高斯模型的聚乙烯过程设计与控制集成优化

聚乙烯反应过程中物流-能流剧烈交叠、反应-传递相互耦合,使得过程具有强非线性以及多重稳态。传统的顺序设计方法不能保证系统有足够的控制自由度,当存在扰动和过程参数不确定性时,仅依靠设计控制器很难提高产品质量。提出一种聚乙烯工艺稳态设计与运行控制的集成优化方案,创造性地引入Kriging高斯模型同时预测模型动态和模型不确定性。另一个重要的贡献是在聚乙烯工艺设计阶段,设计性能指标,定量描述过程稳态设计对闭环动态的影响。所提出的方法已经通过对气相聚乙烯工艺设计和运行控制的集成优化进行了验证,并在参数不确定性和扰动存在情况下仿真证实了集成优化设计方案的高效性。     

基于图模型的间歇过程误操作风险辨识

提出了一套基于图模型的建模方法,该模型以Petri网和符号有向图（SDG）为基础将模型分为上部和下部,加入操作点、控制库所、判断模块等模型元素,并结合间歇过程的特点,提出了关联变量、目标变量检查表、操作点检查表和关联变量检查表等概念。根据误开误关、过早过晚、步骤添加删除等误操作,对模型进行验证。验证结果表明,该模型解决了先前方法难以描述具体操作的缺陷,并且模型结构简单,具有整体性。不仅能够方便地描述3种不同类型的误操作,还能有效地对误操作进行风险辨识,具有一定的适用性。     

Opportunities and challenges for process control in process intensification

This is a review and position article discussing the role and prospective for process control in process intensification. Firstly, the article outlines the classical role of control in process systems, presenting an overview of control systems’ development, from basic PID control to the advanced model based hierarchical structures. Further on, the paper reviews the research articles discussing control issues of intensified process equipment, specifically of reactive distillation, divided wall distillation, simulated moving bed reactors and micro-scale systems. In the next section, the focus is on more fundamental, dynamic characteristics of selected intensified process categories, which are elucidated in several examples. The goal of this analysis is to stress to the potential challenges for control of intensified processes. More importantly, the aim of this part is to emphasize to the opportunities for control, which are associated with new actuation possibilities arising from process intensification. Finally, a new concept of process synthesis is elaborated, which is based on process intensification and actuation improvement. The concept enables integration of process operation, design and control through dynamic optimization. This simultaneous synthesis approach should provide optimal operation and more efficient control of complex intensified systems. It may also suggest innovative process solutions which are more economically and environmentally efficient and agile.     

Operations optimization and control design for a petroleum distillation process

Process automation involves both steady-state optimization and feedback control. In this paper, the economic optimum steady-state operating conditions for a petroleum crude distillation process are determined using a tray-to-tray model. This model is used to evaluate the steady-state operation achieved with several multivariable process control designs. Only one controller design was found to result in essentially optimum steady-state operation; others deviated significantly. The method applied in this paper relies on a knowledge of the key disturbances occurring in the process; good economic performance may not be obtained should other disturbance types occur. The results demonstrate the importance of implementing the operations optimization through a control strategy which will respond properly to disturbances.     

Nonlinear model-based repetitive control of simulated moving bed process

The simulated moving bed (SMB) process, after more than 40 years of successful operation in the petro-chemical industry, has emerged as one of the most important separation processes in the pharmaceutical, fine chemical, and biotechnology fields. However, optimal operation and automatic control of the SMB process is still challenging because of its complex dynamics caused by periodic port switching and inherent nonlinearity. In this research, a novel advanced control technique for the SMB process has been proposed. In the proposed technique, regulation of both extract and raffinate purities measured at the terminal time of each switching period is performed by a nonlinear repetitive controller which utilizes the past period data as feedback information. The repetitive controller was designed on the basis of a fundamental nonlinear model of the SMB process. Through application to a numerical SMB process, it was found that the proposed control technique performs quite satisfactorily against model error as well as set point and disturbance changes.     

Model-based control of a molten carbonate fuel cell (MCFC) process

To improve availability and performance of fuel cells, the operating temperature of molten carbonate fuel cells (MCFC) stack should be strictly maintained within a specified operation range, and an efficient control technique should be employed to meet this objective. While most modern control strategies are based on process models, many existing models of MCFC are not ready to be applied in synthesis and operation of control systems. In this study, we developed an auto-regressive moving average (ARMA) model and machine learning methods of least squares support vector machine (LS-SVM), artificial neural network (ANN) and partial least squares (PLS) for the MCFC system based on input-output operating data. The ARMA model showed the best tracking performance. A model predictive control method for the operation of MCFC system was developed based on the proposed ARMA model. The control performance of the proposed MPC methods was compared with that of conventional controllers using numerical simulations performed on various process models including an MCFC process. Numerical results show that ARMA model based control provides improved control performance compared to other control methods.     

丙烯酸甲酯-甲醇-水体系逆流萃取过程的模拟

基于某丙烯酸甲酯厂甲醇萃取过程的实际运行数据与实际转盘塔的形式结构,计算了实际转盘塔的理论级数。使用Aspen Plus流程模拟软件,通过对进料组分合理的简化,建立了能够良好描述该萃取设备实际运行工况的模型,并实现了丙烯酸甲酯生产工艺中的萃取塔T303的流程模拟。结果表明,在逆流萃取级数n=3时,模拟结果与实际数据基本吻合。在所建模型基础上,研究了温度、萃取相比、理论级数等操作条件对萃取结果的影响。通过分析和比较不同条件下的模拟结果,提出了能够提高产品质量的建议,也为丙烯酸甲酯生产工艺改造与扩大生产提供了理论依据。     

Model-based design and control of a continuous drum granulation process

This paper is concerned with enhanced process design and control of a multiple-input multiple-output (MIMO) granulation process. The work is based on a first-principles mechanistic three-dimensional population balance model (3D-PBM), which has been previously validated against experiments at the laboratory-scale for various operating conditions and formulations. The main objective of this study is via a novel process design, to control and operate the granulation process under more optimal conditions. Novelty of the work lies in the usage of the validated 3D-PBM to extract suitable multiple control-loop pairings from which an overall control loop performance is qualitatively and quantitatively assessed. Results show that for most existing granulation process configurations, enhanced control-loop performance is not achieved and as a result an alternative process design strategy is necessary. The proposed design demonstrates increased efficiency in the control and operation of the granulation process, which is required for further efficient control and operation of subsequent downstream processes.