ADAPTIVE POLE-PLACEMENT CONTROL OF A CONTINUOUS POLYMERIZATION REACTOR

A simulation of the polymerization of methylmethacrylate in a CSTR is adaptively controlled by two types of pole-placement algorithms. The strongly nonlinear polymerization process, exhibiting multiple steady states, presents difficult control problems for conventional feedback controllers. The performance of an adaptive explicit SISO controller and that of an adaptive implicit multivariable controller are compared and evaluated as applied to this process. The plant is identified by a recursive least squares estimator. Modifications made to the estimation algorithm help to maintain adequate closed-loop results. A simple warm-up procedure is introduced that successfully initializes the controller and estimator during plant start-up. Good servo and regulatory control are achieved by both pole-placement schemes.     

一种基于自适应回归核函数的污水处理能耗模型

针对污水处理过程能耗模型难以建立的问题,提出了一种基于自适应回归核函数的建模方法。通过分析污水处理过程的运行特点,构建能耗与运行过程变量之间的关系,得到一种基于过程变量的能耗模型表达;同时利用梯度下降算法对能耗模型参数进行自适应调整,提高模型精度。最后,将设计的能耗模型应用于污水处理过程基准仿真平台BSM1和实际污水处理厂,实验结果表明该模型能够根据污水处理过程变量实时获得污水处理过程的能耗,具有较好的自适应特性和较高的精度。     

基于多策略自适应差分进化算法的污水处理过程多目标优化控制

针对污水处理过程中的能耗过高和出水水质不达标等问题,提出一种基于多策略自适应差分进化算法的污水处理过程多目标优化控制方法。首先,在常规跟踪控制结构的基础上,增加对第3、4单元溶解氧浓度的跟踪控制,扩大了能耗和出水水质的优化调节范围。然后,设计一种多策略自适应差分进化算法（MSADE）,该算法采用多策略融合变异和排序优选方法,选取合适的变异策略和较优的随机个体引导种群变异,并根据进化过程信息自适应地更新交叉率,以提升算法的收敛性和pareto解的多样性。最后,将MSADE算法与PID控制器相结合,并构建以能耗和出水水质为优化目标的多目标优化问题,实现对溶解氧和硝态氮浓度设定值的动态寻优和跟踪控制。基于国际基准仿真平台BSM1进行验证,结果表明所提的多目标优化控制方法能有效降低污水处理过程的能耗并提升出水水质。     

Combined Physicochemical Treatment of Textile and Mixed Industrial Wastewater

Wastewaters derived from a textile factory and an industrial park were subjected to treatment with ferric chloride coagulation; ozonation; ferric chloride pre-coagulation/Fenton-based process/lime post-coagulation; Fenton-based process/lime post-coagulation; and ferric chloride pre-coagulation/ozonation. Schemes with the Fenton-based process proved the most efficient for treatment of both wastewater samples. The characteristics of wastewater samples treated by a Fenton-based process at H₂O₂/COD weight ratio 0.5:1 complied with the discharge limits stated by regulations for wastewater directed to local sewerage. The Fenton-based process/lime post-coagulation scheme proved more efficient than ferric chloride pre-coagulation/Fenton-based process/lime post-coagulation system. The increase of H₂O₂/COD weight ratio to 2:1 resulted in 5 and 10% of residual COD and DOC, respectively. All studied processes and combined physicochemical treatment schemes, except single ozonation, resulted in toxicity reduction and biodegradability improvement in both wastewater samples. The operational costs of applied treatment schemes were calculated and indicated the Fenton-based process schemes as the most feasible and cost-effective.     

ADAPTIVE CONTROL OF A HEAT EXCHANGER USING FUNCTION BLOCKS

Many adaptive control strategies require on-line identification, which implies that a digital computer is needed for implementation. The objective of the work presented in this paper is to demonstrate that adaptive process control can be accomplished by combining relatively simple digital control algorithms called function blocks. These function blocks are easily implemented in low-level microprocessor-based digital controllers without requiring a computer. The feasibility of these methods is illustrated through an industrial heat exchanger control example, and the performance benefits of this adaptive approach are illustrated by means of simulation results.     

基于水力空化技术的废水处理装置及设计

水力空化技术是一种新的水处理技术。本试验利用两种孔板水力空化装置对若丹明B降解进行了试验研究,试验结果表明：水力空化对若丹明B确实有降解作用。探讨和分析了两种孔板的空化数和进口压力等因素对其降解的影响作用,提出了水力空化降解与时间的规律和不同的孔板存在最佳的操作运行参数的观点。     

MBR工艺处理聚酯废水的运行管理要点

介绍了厌氧-MBR-氧化塘联合工艺用于聚酯废水处理的工艺流程和处理效果。重点探讨了工艺过程中主要构筑物的运行、控制要点。介绍了MBR池在运行管理中常见的故障,进行了原因分析,并给出排除的方法。采用该法处理聚酯废水,提高了活性污泥浓度,极大地改善了聚酯废水处理中好氧过程的效率,具有良好的经济技术可行性,处理效果持续稳定。     

ADAPTIVE CONTROL OF A HEAT EXCHANGER USING FUNCTION BLOCKS

Many adaptive control strategies require on-line identification, which implies that a digital computer is needed for implementation. The objective of the work presented in this paper is to demonstrate that adaptive process control can be accomplished by combining relatively simple digital control algorithms called function blocks. These function blocks are easily implemented in low-level microprocessor-based digital controllers without requiring a computer. The feasibility of these methods is illustrated through an industrial heat exchanger control example, and the performance benefits of this adaptive approach are illustrated by means of simulation results.     

稀土湿法冶炼废水污染治理技术与对策

简述了稀土湿法冶炼废水的来源、分类及污染物特性,重点分析了稀土湿法冶炼废水中氨氮、氟化物、盐酸、硫酸及草酸污染物的源头控制、资源综合利用与环保治理技术现状。结果表明,利用氟生产冰晶石是稀土湿法冶炼过程中氟污染治理和资源回收的有效方法;非皂化工艺是稀土分离工艺的发展方向,采用MVR蒸发工艺回收氯化铵是目前稀土氨皂化废水中高浓度氨氮污染治理的最优工艺;草酸沉淀母液的共沸蒸馏回收盐酸和草酸资源化处理工艺具有工业应用前景;“膜处理+MVR蒸发”工艺在解决稀土冶炼废水中低浓度氨氮和有机污染物治理难题上具有一定的技术优势。提出了改进生产工艺、提高资源综合利用率,实行废水的分类收集、分级回用与分质处理,开发废水的深度处理与回用工艺是实现稀土湿法冶炼废水污染物综合治理的有效途径。     

兰炭废水处理工艺技术评述

分析了兰炭废水的水质特点,介绍了兰炭废水处理的典型工艺流程,并对各种工艺技术原理和优缺点进行了分析论述。同时根据工程案例和实验结果提出了推荐意见,对兰炭废水处理的工程应用具有一定指导意义。     

基于工况识别的污水处理过程多目标优化控制

针对污水处理过程中能耗大和罚款高等问题,设计了一种基于工况识别的污水处理智能优化控制系统。为保证工况识别的准确性和实时性,利用自适应遗传算法从多种入水参数中选取参考变量,然后基于建立的历史知识库,对入水实时工况进行识别。针对能耗和罚款的多目标优化问题,基于历史知识的引导,通过智能决策的方法从 p a r e t o 解集中选出最优偏好解,并对知识库进行更新。利用国际基准仿真平台BSM1进行验证,结果表明所提方法有效利用了历史工况的最优解信息,提高了算法的收敛性,降低了计算成本,同时可将能耗和罚款控制在较低的范围。     

氯碱生产污水处理方案

介绍氯碱生产废水综合处理工艺方案、污水三级处理方案、污泥工艺处理方案。提出氯碱生产废水适合采用水解酸化+接触氧化+水解酸化+BAF工艺,三级处理适合采用人工湿地技术,污泥处理适合采用填埋工艺。提倡各氯碱企业针对废水水质特点,结合自身的生产实际,采取经济有效的处理方案。     

Membrane bioreactor technology for wastewater treatment and reuse

Treatment technology for water recycling encompasses a vast number of options. Membrane processes are regarded as key elements of advanced wastewater reclamation and reuse schemes and are included in a number of prominent schemes world-wide, e.g. for artificial groundwater recharge, indirect potable reuse as well as for industrial process water production. Membrane bioreactors (MBRs) are a promising process combination of activated sludge treatment and membrane filtration for biomass retention. This paper will provide an overview of the status of membrane bioreactor applications in municipal wastewater reclamation and reuse in Europe and will depict their potential role in promoting more sustainable water use patterns. Particular attention will be paid to the impact of MBR technology on emerging pollutants. A case study will be presented on a full-scale MBR plant for municipal wastewater which is operated by Aquafin in Belgium.     

食品添加剂废水综合处理

通过分析食品添加剂废水成分,探讨了现有混合废水处理工艺存在的问题,提出了在现有混合废水处理工艺前增设预处理工序的方案。对混合废水通过Fenton氧化、混凝沉淀等方法进行预处理后,现有污水处理工艺可以正常运行。工艺改造后的运行结果表明:经过预处理的混合废水再经原废水站处理后,出水水质能达到工业园区废水接管标准。由于混合废水得到综合利用,废水排放量也相应减少。     

A CLUSTERED CLASS DISTRIBUTION APPROACH FOR PROCESS MONITORING AND FAULT DETECTION

Clustering algorithms have been useful for fault detection of process systems. Among many algorithms, ART2 neural networks have provided good results for fault detection and identification. In this article, a new algorithm for fault detection is proposed that is based on clustered classes from ART2 neural networks. An index for detecting changes of process state is defined, to represent differences between recent class distribution and historical class distribution. The proposed algorithm was applied to detection of state change of an industrial wastewater treatment process and was shown to be effective in detecting a change in the process.     

A CLUSTERED CLASS DISTRIBUTION APPROACH FOR PROCESS MONITORING AND FAULT DETECTION

Clustering algorithms have been useful for fault detection of process systems. Among many algorithms, ART2 neural networks have provided good results for fault detection and identification. In this article, a new algorithm for fault detection is proposed that is based on clustered classes from ART2 neural networks. An index for detecting changes of process state is defined, to represent differences between recent class distribution and historical class distribution. The proposed algorithm was applied to detection of state change of an industrial wastewater treatment process and was shown to be effective in detecting a change in the process.     

反渗透技术在碳酸钾生产废水处理中的应用

对碳酸钾生产中产生的废水进行了概述,针对目前生产情况和环保要求,经过多方面探讨,确定采用反渗透膜技术处理该废水,介绍了反渗透膜处理技术的工艺流程,详细说明了反渗透处理废水的应用经验及效果。分析了反渗透的优势与不足,提出了今后的改进设想。     

Nonlinear temperature control of a batch suspension polymerization reactor

This paper concerns nonlinear temperature control of a batch polymerization reactor where suspension polymerization of methyl methacrylate (MMA) takes place. For this purpose, four control algorithms, namely, a fix proportional‐integral (PI) controller, an adaptive proportional‐integral‐derivative (PID) controller and two globally linearizing control (GLC) schemes, one for known kinetic model (GLC‐I) and the other for unknown kinetic model (GLC‐II), are selected. The performances of these controllers are compared through simulation and real‐time studies in the presence of different levels of parameter uncertainty. The results indicate that GLCI and GLC‐II have better performances than fix PI and adaptive PID, especially in case of strong gel effect. The worst performance belongs to adaptive PID because of rapid model changes in gel effect region. GLC‐II has a simpler structure than GLC‐I and can be used without requiring the kinetic model. In implementation of GLC‐I the closed loop observer should be used because of model uncertainties.     

基于多目标粒子群算法的污水处理智能优化控制

为了满足污水处理过程出水水质排放达标的同时降低运行能耗,提出了一种基于多目标粒子群的污水处理多目标智能优化控制方法。首先,通过分析污水处理运行数据,建立了基于自适应回归核函数的污水处理能耗和出水水质模型;其次,设计出一种污水处理多目标优化方法,利用多目标粒子群优化算法同时对污水处理自适应能耗和出水水质模型进行优化,获得溶解氧和硝态氮浓度的优化设定值;最后,利用PID控制器对溶解氧和硝态氮浓度优化设定值进行跟踪控制,实现了污水处理过程的多目标优化控制。基于污水处理基准仿真平台BSM1的实验结果显示,该多目标优化控制方法不但能够保证出水水质达标,而且能有效降低污水处理过程的能耗。     

氟环唑生产废水的测定及评价

文章就氟环唑生产废水综合处理工艺流程讨论了其废水中污染物的测定方法,为工业园区氟环唑生产废水的监测方法提供了技术支持,同时通过结果分析与评价,为氟环唑生产废水达标排放提供理论依据。