Process integration design methods for water conservation and wastewater reduction in industry

This three part series of papers addresses operational techniques for applying mass integration principles to design in industry with special focus on water conservation and wastewater reduction. Part 1 covers design techniques for any number of wastewater streams containing a single contaminant. The technique comprises a two stage graphical approach. In the first stage, the water pinch diagram is used to identify key design targets (such as the minimum freshwater requirement of the studied system, the amount of achievable water recycling and reuse and the water quality concentration bottleneck) for the industrial process of interest. Key practical insights provided by the water pinch diagram are discussed. In the second stage, source–sink mapping diagrams are used to identify the water recycling and reuse network, and any alternative networks, that achieve the identified targets. A case study is included to illustrate the proposed methodology. Electronic Publication     

Process integration design methods for water conservation and wastewater reduction in industry

This paper is part 2 of a three-part series of papers addressing operational techniques for applying mass integration design in industry with special focus on water conservation and wastewater reduction. This paper presents a design technique for any number of wastewater streams containing multiple contaminants. The technique comprises a single non-linear optimization program to minimize the wastewater discharged (or maximize the amount of recycled wastewater). This program is developed based on general water allocation principles and uses the transshipment model theory to allow the "shipment" of wastewater (referred to as "sources" or "warehouses") to process water users (referred to as "sinks", "demands" or "customers"). A detailed case study of industrial significance, highlighting land treatment technology, is included to illustrate the proposed methodology and various process scenarios are evaluated within this case study to demonstrate the general applicability of the proposed optimization program.     

On the use of graphical analysis for the design of batch water networks

This paper presents a series of graphical analyses for the design of batch water networks to process systems characterized by fixed flow rate operations. Water integration is carried out by exploiting all water reuse opportunities, with which both freshwater consumption and wastewater generation can be reduced at the same time. Throughout the analyzing procedure, the minimum freshwater consumption is first identified. Under the already set freshwater target, the follow-up analyses are continued to cut down the number of storage tanks for the simplification of the network complexity. The resultant network structure is finally obtained with the corresponding storage policy. After water integration to the literature case study, more than 54 and 63% of savings in freshwater, with more than 61 and 72% of reductions in wastewater are reported for the single and cyclic batch productions, respectively, compared to the base case without water reuse.     

Modified fully utilized design (MFUD) method for stress and displacement constraints

The traditional fully stressed method performs satisfactorily for stress-limited structural design. When this method is extended to include displacement limitations in addition to stress constraints, it is known as the Fully Utilized Design (FUD). Typically, the FUD produces an overdesign, which is the primary limitation of this otherwise elegant method. We have modified FUD in an attempt to alleviate the limitation. This new method, called the Modified Fully Utilized Design (MFUD) method, has been tested successfully on a number of problems that were subjected to multiple loads and had both stress and displacement constraints. The solutions obtained with MFUD compare favourably with the optimum results that can be generated by using non-linear mathematical programming techniques. The MFUD method appears to have alleviated the overdesign condition and offers the simplicity of a direct, fully stressed type of design method that is distinctly different from optimization and optimality criteria formulations. The MFUD method is being developed for practicing engineers who favour traditional design methods rather than methods based on advanced calculus and non-linear mathematical programming techniques. The Integrated Force Method (IFM) was found to be the appropriate analysis tool in the development of the MFUD method. In this paper, the MFUD method and its optimality are examined along with a number of illustrative examples. © 1998 This paper was produced under the auspices of the U.S. Government and it is therefore not subject to copyright in the U.S.     

超滤膜法城市污水深度处理中水回用中试试验研究

以高碑店污水处理厂二级出水为处理对象，建立日产中水500t的超滤中试试验装置，研究膜法城市污水深度处理中水回用的工艺和操作条件，考察所能达到的技术经济指标，掌握放大规律，为万吨级工业装置和系统的设计提供基础数据．试验装置连续运行了约2500h，膜性能稳定，产水水质达到生活杂用水标准(CJ．25．1—89)。     

Aggregate nonparametric safety analysis of traffic zones

Exploring the significant variables related to specific types of crashes is vitally important in the planning stage of a transportation network. This paper aims to identify and examine important variables associated with total crashes and severe crashes per traffic analysis zone (TAZ) in four counties of the state of Florida by applying nonparametric statistical techniques such as data mining and random forest. The intention of investigating these factors in such aggregate level analysis is to incorporate proactive safety measures in transportation planning. Total and severe crashes per TAZ were modeled to provide predictive decision trees. The variables which carried higher weight of importance for total crashes per TAZ were – total number of intersections per TAZ, airport trip productions, light truck productions, and total roadway segment length with 35 mph posted speed limit. The other significant variables identified for total crashes were total roadway length with 15 mph posted speed limit, total roadway length with 65 mph posted speed limit, and non-home based work productions. For severe crashes, total number of intersections per TAZ, light truck productions, total roadway length with 35 mph posted speed limit, and total roadway length with 65 mph posted speed limit were among the significant variables. These variables were further verified and supported by the random forest results.     

Design and topology/shape structural optimisation for additively manufactured cold sprayed components

Integrating advanced structural optimisation, such as topology optimisation (TO), with additive manufacturing (AM) allows design and fabrication of extremely efficient and effective components. Such integration is challenging because characteristics can vary from process to process. In this paper, designing and optimising a part for the cold spray AM process is demonstrated. Cold spray process characteristics and constraints are enforced throughout. The analysis shows a tradeoff between stress and mass, but the combined process delivers a structure at much lower stress (up to 3X reduction in peak stress in a case study) with the capability to be much lighter than the original part (case study: 20% reduction in weight). The general approach to specifying design guidelines, interpreting TO results, and applying other structural optimisation methods is directly applicable to many AM processes – and especially other spray deposition techniques – in addition to cold spray.     

OPTIMIZATION OF A WATER RESOURCES SYSTEM BY NON-LINEAR PROGRAMMING

Optimization of a water resources system necessarily must appropriately mesh the modeling of the system with the optimization technique used. If the system model is linear, many effective optimization techniques exist. But if the model is non-linear in the objective function and/or constraints, very few effective optimization methods exist. This paper describes how a water resources system, including both water quantity and water quality, can be modeled to form a non-linear programming problem. The latter is solved by two techniques: (a) a Generalized Reduced Gradient method, and (b) a conjugate gradient projection method. The relationship between the model and the formulation of the non-linear programming problem is discussed, and computational experience with each of the algorithms is described.     

Rapid, State-of-the-Art Techniques for the Detection of Toxic Chemical Adulterants in Water Systems

Recent events have heightened awareness concerning potential hazardous threats to U.S. populace. The causes of concern include a possible contamination of water systems through harmful chemical agents resulting in sickness or death among consumers. To forestall the consequences of high-risk chemical contaminants that can potentially pollute our water resources, swift intervening measures need to be taken as a first line of defense. This aspect of environmental protection involves the design, testing, and installation of detection devices that protect U.S. water supply systems from toxic chemicals. These sensing devices are based on physical, chemical, biological, and radiological methods of detection. Traditional analytical tools are rather cumbersome, time-consuming, and expensive to operate. On the other hand, contemporary trends in the fight against toxic chemical threats to domestic and industrial water facilities comprise of sensors designed to achieve rapid, highly sensitive, and cost-effective detection, and intervention. This paper samples the state-of-the-art in detection techniques for toxic chemical antagonists with emphasis on heavy metals and cyanide compounds that can be potentially deleterious to U.S. water systems. The goal is to identify rapid, realistic and reliable methods, as early warning systems, to mitigate the effects of toxicants in water systems.     

Recycling of bleach plant effluent of an Indian paper mill using water cascade analysis technique

A systematic approach to optimizing water network has traditionally been utilized to examine and plan water conservation in industrial processes. In the present case study, water cascade analysis was used to analyze and optimize the water network of a bleaching section of an Indian paper mill. Water system integration can minimize both the freshwater consumption and wastewater discharge of a paper mill. Three limiting constraints, i.e., Chemical oxygen demand, Total dissolved solids, and Adsorbable organic halides (AOX), were considered for the study; after analysis, AOX was found to be a critical limiting constraint. A nearest neighbor algorithm (NNA) was used to distribute the fresh water and recycled water among the plant operations. After the application of WCA and NNA in the bleaching section, 41.75% of fresh water consumption and 70.67% of wastewater generation could be reduced.     

基于“虚实”联动模式的旅游APP产品设计

At present, in the public leisure life, the instant social sharing and interaction on digital mobile terminal has become a popular way of Internet entertainment experience, and the design of the integrated service system of tourism is also developing to mobile, instant, multi-functional integration direction. The work aims to explore integration and innovation development of design on social sharing APP and comprehensive tourism service in the era of mobile leisure. The comprehensive service APP design of the tourist destination was taken as the research object. From the concept and strategy of APP product design and service design, the basis of convergence and the linkage implementation process were analyzed in combination with the user experience design and system design methods. As the APP design is based on the function extension and linkage design of tourist destination service system, it is necessary to consider how to connect the "real" format foundation during the tour process and the "virtual" user ex-perience design of the software, which is of great significance for exploring how to use the information exchange design to upgrade and transform the traditional service industry.     

Development of a MINLP model for the optimization of a large industrial water system

This paper presents the design of a large water system within the production and packaging areas of a brewery. In order to accomplish the task, mathematical models were developed based on a Mixed Integer Nonlinear Programming (MINLP) formulation from the open literature. These models enable the investigation of several integration options: a) direct water re-use between batch and semi-continuous consumers operating within the same time interval and b) regeneration re-use options, by designing and scheduling an on-site wastewater treatment system. A multilevel strategy was applied for this large-scale industrial problem, which firstly decomposes design problem into several smaller integration problems concerning water consumers within each section of the brewery. At the following level, water re-use and regeneration re-use opportunities between the brewhouse and the packaging areas were explored for each working day. Finally, the design of an integrated water system was performed over the entire working week by fixing identified intra-daily matches between sections. An optimum water integration scheme is proposed based on the results obtained.     

Radiation protection standards: their evolution from science to philosophy

The concept of applying constraints on individual sources to a small fraction of the public dose limit has been deemed inappropriate when shielding the medical X-ray sources. This represents a broad-based consensus of medical physics and radiological societies in the United States, and the report series on the shielding design for medical X-ray sources (including dental, X-ray imaging and therapeutic X ray) from the National Council on Radiation Protection and Measurements (NCRP) utilises 1 mSv y(-1) as a source control limit. In the present study, the rationale for such a conclusion is discussed, and a somewhat critical look at the current model of radiation protection of the public is made.     

Safety assessment in plant layout design using indexing approach: implementing inherent safety perspective. Part 1 - guideword applicability and method description

Layout planning plays a key role in the inherent safety performance of process plants since this design feature controls the possibility of accidental chain-events and the magnitude of possible consequences. A lack of suitable methods to promote the effective implementation of inherent safety in layout design calls for the development of new techniques and methods. In the present paper, a safety assessment approach suitable for layout design in the critical early phase is proposed. The concept of inherent safety is implemented within this safety assessment; the approach is based on an integrated assessment of inherent safety guideword applicability within the constraints typically present in layout design. Application of these guidewords is evaluated along with unit hazards and control devices to quantitatively map the safety performance of different layout options. Moreover, the economic aspects related to safety and inherent safety are evaluated by the method. Specific sub-indices are developed within the integrated safety assessment system to analyze and quantify the hazard related to domino effects. The proposed approach is quick in application, auditable and shares a common framework applicable in other phases of the design lifecycle (e.g. process design). The present work is divided in two parts: Part 1 (current paper) presents the application of inherent safety guidelines in layout design and the index method for safety assessment; Part 2 (accompanying paper) describes the domino hazard sub-index and demonstrates the proposed approach with a case study, thus evidencing the introduction of inherent safety features in layout design.     

Application of cleaner technologies in milk processing industry to improve the environmental efficiency

Changes in production processes and products that result in improvement of environmental, economic and social performance of enterprises are an important element of the overall process towards more sustainable production. The aim of this article is to demonstrate the application of cleaner production and eco-design as sustainable production tools to improve the environmental efficiency of milk processing industry. Milk processing industry is one of the largest and dynamically developing branches of industry in the world. The main impact of milk processing industry on the environment is related to energy and water consumption, and waste and wastewater generation. A number of potential solutions to improve the environmental performance of milk processing industry, to reduce energy and resources consumption are analysed: substitution of cleaning agent in the milk receiving bar for washing of milk tankers with the specialised acidic detergent, integration of the automated CIP washing system in the butter bar, implementation of water recycling system to collect warm (35?°C) water, integration of the membrane technologies for the evaporation process and the use of filtrate received during the condensation for steam generation in the boiler house. Finally, an eco-design solution for cans of milk products is presented. All these proposals have been implemented in the milk processing company.     

问题求解视角下工程机械产品的体验设计研究

目的 从问题求解的角度出发,构建工程机械产品的体验设计层级,探讨各层级对应的问题求解内涵。方法 通过文献研究法,梳理设计问题求解的研究脉络,奠定理论出发点,即设计问题求解方式已经从产品拓展到了体验设计。基于工程机械产品及行业的特殊性,分别从工程性思考和B2B行业视角分析工程机械问题求解的特点。借助实证案例分析方法,结合工程机械行业所涉及到的众多利益相关者,提出由用户体验(UX)、客户体验(CX)、品牌体验(BX)构成的工程机械体验设计层级,并对各层级问题求解内容及方式进行了阐释。结论 用户体验涉及到物理层的可用性问题和行为层的交互问题;客户体验关系到服务层的价值问题;品牌体验主要关注系统层的整合问题。未来工程机械产品问题求解的核心思路将是以“体验设计目标”为整体出发点。     

表面处理行业废水的治理与回用标准化探讨

直接排放表面处理废水将严重污染环境,彻底治理废水是表面处理行业生存和发展的必由之路。为了解决企业废水处理所面临的困难、规范废水治理技术、促进我国表面处理行业废水处理水平,建立完整的废水治理与回用标准体系已成为表面处理行业亟待解决的问题。阐述了建立表面处理废水治理和回用标准的必要性及标准化应遵行的原则,着重介绍了标准化体...     

Low-velocity impact-induced damage of continuous fiber-reinforced composite laminates. Part I. An FEM numerical model

A numerical model for simulating the process of low-velocity impact damage in composite laminates using the finite element method is presented in this paper, i.e. Part I of this two part series on the study of impact. In this model, the 9-node Lagrangian element of the Mindlin plate with consideration of large deformation analysis is employed. To analyze the transient response of the laminated plates, a modified Newmark time integration algorithm previously proposed by the authors is adopted here. We also proved that the impact process between a rigid ball and laminated plates is a stiff system, therefore a kind of A(α) stable method has been advocated here to solve the motion equation of the rigid ball. Furthermore, various types of damages including delamination, matrix cracking and fiber breakage, etc. and their mutual influences are modeled and investigated in detail. To overcome the difficulty of numerical oscillation or instability in the analysis of the dynamic contact problem between delaminated layers using the traditional penalty methods, we have employed dynamic spring constraints to simulate the contact effect, which are added to the numerical model by a kind of continuous penalty function. Moreover, an effective technique to calculate the strain energy release rate based on the Mindlin plate model is proposed, which can attain high precision. Finally, some techniques of adaptive analyses have been realized for improving the computational efficiency. Based on this model, a program has been developed for numerically simulating the damage process of cross-ply fiber-reinforced carbon/epoxy composite laminates under low-velocity impact load. In Part II, this numerical model will be verified by comparing with the experimental results. Also the impact damage will be investigated in detail using this numerical approach.     

A review of the ‘taguchi methods’ for off-line quality control

The Taguchi methods have recently become popular in the U.S.A following a realization of their importance in Japanese quality design. This review is an initial attempt to extract the important ideas while drawing on the ‘Western’ experience with response surface methodology and experimental design.     

Ultrapture water: More than membrane technology alone

The world market for Ultrapure water is currently estimated at around US$ 2.3 billion per annum. Specialised journals dedicated to this subject are published within the water treatment world, where “everybody” uses the term ultrapure water. However, the time when it was enough to use a reverse osmosis (RO) system followed by ion exchange to produce ultrapure water seems like a long time ago, although in fact it is only about 20 years! Today, the demand for purity comes from the semiconductor industry, which sometimes requires purities that are beyond the detection limit of existing analytical equipment. To counter this, the approach towards the production of Ultrapure water has shifted from a series of unit operations to an integrated system design. In this article, Dr Tony Franken from the Membraan Applicatie Centrum Twente (MACT) in The Netherlands gives an insight into the production of ultrapure water.