Ultrasonic bioleaching of Ni, Cu, and Co from sulfide ores: process intensification and efficiency optimization

Proposed research method intensification of heat exchange in biogas reactions using alternative energy sources. The distribution of active and passive methods of heat exchange intensification is determined. The three most effective methods of heat exchange intensification are identified: the method of flow turbulence in the adjacent areas, based on purposeful artificial creation of small dry wall zones, which is the source of additional flow turbulence; the method of flow winding inside the twisted oval tubes and at longitudinal and transverse winding of tightly packed beams and tubes; the method of controlled break-out of the boundary layer at transverse tubulars by creating turboblicators on them. It is determined that in practice the most effective is the use of combined methods of intensification. The important conditions for choosing the method of heat exchange intensification are: the amount of permissible energy costs for heat exchange intensification and the type of energy available for this energy; the task of heat exchange intensification in a particular class of equipment; the technological capacity of equipment with heat exchange intensification, availability at purchase and durability in operation of equipment; the nature of distribution, structure of thermal flows and temperature fields, in which there is a need for intensification of heat exchange. The main indicator of intensification of the heat exchange process in the equipment is found – the efficiency of the process, that is, the process should be economically profitable. From the above it appears that the intensification of heat exchange can’t be considered isolated from the necessary energy costs. The determining criterion of optimization is the efficiency of the heat exchange process at a given level of energy consumption at transfer of the working environment through the equipment. Heat exchange intensification during use of gaseous working environments is of particular importance, for which characteristic reduction of intensity of heat exchange processes and high energy consumption for removal of supports at pumping of gases is characteristic. Tasks of heat exchange intensification are usually set: to reduce the size and weight of heat exchange devices; to decrease the temperature pressure, i.e. to decrease the temperature of the walls at the given temperature of heat carrier or to increase the temperature of heat carrier at the given temperature of walls. Reduction of thickness of heat transfer wall and increase of its thermal conductivity, as well as prevention waste contamination on the wall is an obvious method of intensification of heat exchange.

Приведены результаты лабораторных исследований на обогатимость серебро-полиметаллических руд месторождения Гольцовое флотационным методом обогащения на Омсукчанской обогатительной фабрике. Представлены результаты ситового анализа отвальных хвостов экспериментальной пробы МТП 101 (7577-и), которые свидетельствуют о том, что большое количество серебра (123г/т) теряется в классе крупности 0,040мм (выход 50,25). По результатам минералогического анализа установлено, что основные потери благородного металла связаны с его тонкой вкрапленностью в оксидах, сульфидах и силикатной породе. Основные минералы серебра акантит и полибазит, в классе 0,040мм кюстелит. Экспериментальные исследования проводились в два этапа. Цель первого этапа выявить степень влияния тонины помола в питании флотации (при содержании готового класса 0,074мм в диапазоне 60-95) на извлечение серебра при различных расходах бутилового ксантогената калия (50, 150, 300г/т). Цель второго этапа оценка эффективности применения сульфидизации при различном расходе сернистого натрия Na2S9H2O (50, 150, 200, 450, 750г/т 1-ного водного раствора) в условиях оптимального реагентного режима, установленного на первом этапе исследований. Представлены результаты опытов по определению оптимальной тонины помола и исследований на обогатимость серебро-полиметаллической руды при использовании сернистого натрия в качестве сульфидизатора. Дана оценка эффективности применения процесса сульфидизации. Установлены следующие экспериментальные зависимости извлечения серебра: от степени измельчения и расхода бутилового ксантогената калия от изменения степени тонины помола и расхода сернистого натрия (при расходе бутилового ксантогената калия 150г/т) от степени помола при оптимальном расходе сернистого натрия 150г/т и бутилового ксантогената калия 300г/т. Дана сравнительная оценка изменения показателя извлечения серебра от степени тонины помола до и после добавок сернистого натрия (расход собирателя 150г/т). Приведены математические модели, описывающие зависимость извлечения серебра от технологических параметров, позволяющие управлять процессом флотации труднообогатимого сырья с большим количеством первичных шламов и склонностью руды к ошламованию при измельчении и обогащении (вторичные шламы). Экспериментально установлен оптимальный расход флотационных реагентов: сернистого натрия 150г/т, бутилового ксантогената калия 300г/т при рациональной тонине помола (содержание готового класса 0,074мм в питании флотации 85-95). Абсолютное извлечение серебра из руды серебро-полиметаллического месторождения Гольцовое по сравнению с технологическими показателями Омсукчанской обогатительной фабрики, перерабатывающей руды месторождения Гольцовое по стандартному режиму, повысилось на 14,1 (с 70,7 до 84,8) при выходе концентрата 9,09 за счет интенсификации извлечения серебросодержащих полуокисленных сульфидов с пониженной флотоактивностью и компенсации высокой поглотительной способности тонких частиц. Количество серебра в классе крупности 0,040мм в пробе МПТ 101 (7698-и) после использования сульфидизации составило 83г/т при выходе 72,01, что свидетельствует об эффективности процесса. Потери серебра с хвостами обогащения уменьшились на 40г/т (32,52). Это доказывает возможность переработки серебро-полиметаллических руд месторождения Гольцовое без шихтовки.

Conventional energy sources are limited and non-renewable and their consumption contributes to greenhouse gas emissions. The world is in need of advanced biorefineries to meet ever growing energy demands associated with population growth and economic development. An advanced biorefinery should use renewable and sustainable (both in quality and quantity) feedstock that gives rise to higher energy gains with minimum non-renewable energy and resource consumption. Development of advanced biorefineries is currently encircled by two major issues. The first issue is to ensure adequate biofuel feedstock supplies while the second issue is to develop resource-efficient technologies for the feedstock conversion to maximize energy and economic and environmental benefits. While microalgae, microbial derived oils, and agricultural biomass and other energy crops show great potential for meeting current energy demands in a sustainable manner, process intensification and associated synergism can improve the resource utilization efficiency. Synergism of process intensification tools is important to increase energy efficiency, reduce chemical utilization and associated environmental impacts, and finally process economics.

Conventional energy sources are limited and non-renewable and their consumption contributes to greenhouse gas emissions. The world is in need of advanced biorefineries to meet ever growing energy demands associated with population growth and economic development. An advanced biorefinery should use renewable and sustainable (both in quality and quantity) feedstock that gives rise to higher energy gains with minimumnon-renewable energy and resource consumption. Development of advanced biorefineries is currently encircled by two major issues. The first issue is to ensure adequate biofuel feedstock supplies while the second issue is to develop resource-efficient technologies for the feedstock conversion to maximize energy and economic and environmental benefits. While microalgae, microbial derived oils, and agricultural biomass and other energy crops show great potential for meeting current energy demands in a sustainable manner, process intensification and associated synergism can improve the resource utilization efficiency. Synergism of process intensification tools is important to increase energy efficiency, reduce chemical utilization and associated environmental impacts, and finally process economics. Among the many process intensification methods, this commentary provides a perspective on the essential role of MWs and US and their synergy in biofuel production. Individual, sequential, and simultaneous applications of MWs and US irradiations can be utilized for process intensification of various biofuels production and selective recovery of high value bioproducts. Process related barriers, namely mass and heat transfer limitations, can be eliminated by this synergism while improving the reaction efficiency and overall process economics significantly. In this article, a brief review focused on recent developments in MW and US mediated process intensification for biofuel synthesis and associated issues in their synergism followed by a discussion on current challenges and future prospective is presented.

Background: Ethyl lactate is an environmentally benign solvent, which could substitute petrol-based volatile organic compounds (VOCs) in many applications if production costs are reduced. It is usually produced by the esterification of lactic acid with ethanol - two important chemical building blocks of biorefineries that are available at industrial scale. Reactive distillation is a promising alternative production process, which utilises process intensification to increase energy efficiency and space-time yield by enhancing the reaction kinetics. Methods: In this work, process intensification of ethyl lactate production by means of distillation was analysed with special focus on the efficient separation of water.Different setups were evaluated. The feedstock requirements were studied and the process was optimized regarding reaction kinetics in experiments on laboratory level. The preparation of anhydrous starting mixtures for ethyl lactate formation was tested in batch experiments and applied to reactive distillation. The simultaneous distillation was optimized and assessed for its energy efficiency. For this purpose, integrated reactive distillation was compared to a simple setup for distillation enhanced esterification. Results: It was found that an optimized serial setup of reactors and distillation steps can offer similar process intensification at a lower distillate rate compared to simultaneous reactive distillation and is therefore more energy efficient. Moreover, the serial setup is more flexible and straight-forward to regulate and scale-up. Conclusions: Based on the experimental results, the optimal setup and parameters of a continuous process for ethyl lactate production by distillation enhanced esterification was presented.

Background: Ethyl lactate is an environmentally benign solvent, which could substitute petrol-based volatile organic compounds (VOCs) in many applications if production costs are reduced. It is usually produced by the esterification of lactic acid with ethanol – two important chemical building blocks of biorefineries that are available at industrial scale. Reactive distillation is a promising alternative production process, which utilises process intensification to increase energy efficiency and space-time yield by enhancing the reaction kinetics. Methods: In this work, process intensification of ethyl lactate production by means of distillation was analysed with special focus on the efficient separation of water. The feedstock requirements were studied and the process was optimized regarding reaction kinetics in experiments on laboratory level. The preparation of anhydrous starting mixtures for ethyl lactate formation was tested in batch experiments and applied to reactive distillation. The simultaneous distillation was optimized to ensure that the by-product water was separated efficiently and the separation capacity was not limiting the reaction rate. Combined reactive distillation was compared to a serial setup of reactors and distillation steps. Results: It was found that an optimized serial setup can offer similar process intensification at a lower distillate rate compared to simultaneous reactive distillation. Conclusions: The serial setup is more flexible and straight-forward to regulate and scale-up. Based on the experimental results a continuous production process that uses process intensification to reach high ethyl lactate yield and purity was proposed.

In this paper, to improve the current efficiency in the copper electrowinning process is taken as the research objective. In the traditional production process, sulfate ion concentration, copper ion concentration and current density are carried out according to the empirical value, which cannot ensure the current efficiency to reach the optimal level. Therefore, firstly, this paper proposes a BP neural network model to improve the current efficiency according to the relationships between sulfate ion concentration, copper ion concentration, current density and the established BP neural network model is trained by using real data from the enterprise. The simulation results indicate that there is a definite error between the predicted current efficiency and corresponding to the current efficiency measured at the production site. It is proposed that the BP neural network improved by the improved PSO to further improve the prediction accuracy of the BP neural network. Simulation results indicate that the prediction error of the current efficiency is greatly reduced that meets the accuracy requirements. On the premise of guaranteeing the quality of copper electrowinning, the current density, sulfate ion concentration and copper ion concentration corresponding to the maximum current efficiency accurately predicted by this method can be respectively adjusted in real-time in the copper electrowinning process, which realizes the optimization of current efficiency in the process of copper electrowinning under the background of low carbon and environmental protection.

Automation in agricultural machinery is a crucial driver of productivity and sustainability. Some automation features like automated steering and real-time data analytics are already state-of-the-art. On the other hand, a human driver performs the optimization of the working speed manually, and the automation of this is an ongoing challenge. Process quality and process efficiency are the two main targets in this optimization. Agricultural soil tillage requires achieving both. Therefore, the correlation between process quality optimization and process efficiency is fundamental, and vice versa. The approach presented in this paper shows how the two optimization targets of efficiency and process quality can be optimized and aligned together. Optical sensors determine various parameters to describe and model the process quality. The measured machine state determines the characteristics of the interaction forces between the machine and the environment. A machine learning algorithm describes the relationships in the drivetrain. The two process targets are each predicted for different working speeds and are combined in the form of a boundary target and an optimization target to identify one optimized target speed value.

Process intensification which means the enhanced efficiency of a particular process was first brought into the limelight by Ramshaw in the year 1983. Basically, process intensification consists of finding out and using novel apparatus and techniques which can bring an increase in product yield or decrease in equipment size for a given production capacity. It can also bring about the decrease in energy consumption or reduction in waste production. Process intensification can be achieved through two different paths by the development of novel equipment or methods. The novel equipment can be further classified into (those for conducting chemical reactions) static mixer reactor, spinning disk reactors, etc., and (those which do not involve chemical reactions) static mixer reactor, compact heat exchangers, etc. Microreactor technology which is a boon nowadays enables the production of miniature components for chemical and biochemical systems that involve continuous flow systems usually comprising of two or more phases. The present work aims to review a complete status of process intensification in various fields of energy in India and abroad and their applications for the betterment of science and technology.

Iterative optimization of the economic efficiency of an industrial process within the validity area of the static plant model and its application to a Pulp Mill

The manufacturing industry is challenged by increasing costs of scarce resources, rapid change, and tight competition in global markets, and the need for efficient and sustainable process design and operating strategies. Addressing these challenges has been the focus of process intensification (PI). Polymerization processes face the additional challenge of meeting tight product specifications, which are dictated by the demands of high quality and advanced materials. Meeting these specifications requires the incorporation of complex molecular weight distribution (MWD) models based on population balances of all the polymer chains. Addressing these challenges through process intensification requires the development and application of efficient, robust, and powerful optimization strategies and modeling frameworks, leading to an essential strategy for process intensification of polymerization systems. This survey presents the development and application of novel optimization strategies for model development, p...

Drug substance purification by crystallization is a key interface in going from drug substance synthesis to final formulation and can often be a bottleneck in process efficiency. There has been increased importance in the development of continuous crystallization systems of active pharmaceutical ingredients to produce crystals with targeted physical and biopharmaceutical properties. Continuous spherical crystallization (CSC) is a process intensification technique that can address many of the present flaws (e.g., size distribution, downstream processing efficiency) of traditional crystallization systems. In this study, a novel concept and method in the field of process intensification through continuous spherical crystallization is proposed. This study is based on performing crystallization/spherical agglomeration in an oscillatory flow baffled crystallizer (OFBC). OFBCs are comparable to plug flow crystallizers (PFCs) in that they are both tubular crystallizers; however, the OFBC has periodically spaced orifice baffles with oscillatory motion overlapped on the net flow. Independent crystallization mechanisms can theoretically be achieved through spatially distributed solution, solvent, antisolvent, and bridging liquid addition, offering more control of each mechanism. However, our studies showed that the OFBC allowed for spatially distributed addition of solvents but achieving control of each mechanism individually was not attainable due to the back mixing of the system.

ABSTRACTIn this study, microwave and ultrasound extraction were selected as process intensification tools to intensify the conventional heat reflux extraction process. Process efficiency was evaluated based on total phenolic content (ascorbic acid, neochlorogenic acid, and chlorogenic acid), scavenging ability of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric (Fe3+) free radicals, and process intensification principles and domains. Highest phenolic content and antioxidant activity were achieved using microwave extraction followed by heat reflux and ultrasound extraction. Microwave extraction was selected via decision matrix as a suitable process intensification approach based on results and its ability to satisfy process intensification principles.

Opportunities for process intensification in the UK water industry: A review

Sinter ore is the raw material of the iron and steel production. A sintering production process is with high energy consumption and large CO2 emissions. It is important to achieve the green manufacturing of the sinter ore. In this paper, an optimization and control system for the carbon efficiency (OCSCE) in the green manufacturing of the sinter ore is designed from the point of view of the maximum utilization of the carbon and the best protection of environment in the sintering process. The OCSCE has three parts: the optimization for the carbon efficiency, the coordinated optimization and control for the production phases and the comprehensive performance evaluation for the carbon efficiency. The optimization for the carbon efficiency is used to optimize the state parameters. The coordinated optimization and control for the production phases is applied to optimize and control the operation parameters. The comprehensive performance evaluation for the carbon efficiency assesses whether the carbon efficiency of the whole sintering process is consistent with green manufacturing. Finally, an implementation scheme of the OCSCE is put forward for the industrial site. The results of preliminary tests show that the OCSCE is in line with the needs of the industrial site, and it will have a significant performance after the OCSCE is put into the industrial site.