Process Intensification Technology Research Articles

Supergravity Technology: New Opportunity for the Advance of Electrochemical Industry

Electrochemical industries, pertaining to the production of raw materials and preparation of functional materials, are multi-interdisciplinary involving chemical engineering, metallurgy and material science. The reduction of energy consumption, the improvement of product properties and new materials are the motives for the development of electrochemical industries. The key issues are mass transfer and bubble disengagement. Supergravity as a new process intensification technology has attracted more and more attention. The intensification actions of supergravity on mass transfer and bubble disengagement are analyzed theoretically in this paper. It is confirmed that chlor-alkali electrolysis and water electrolysis can be enhanced obviously due to the rapid disengagement of gas bubbles from electrolytic system under supergravity field. The structure and properties of electrodeposited functional materials (such as metal foils, active electrode and conductive polymer) can be also adjusted. Supergravity technology is an opportunity to advance the traditional electrochemical engineering.

ChemInform Abstract: Advances in Solid‐Catalytic and Non‐Catalytic Technologies for Biodiesel Production

AbstractReview: 207 refs.

ChemInform Abstract: Microwave, Ultrasound and Ball Mill Procedures for Bio‐Waste Valorisation

AbstractReview: 66 refs.

Advanced biodiesel production technologies: novel developments

Biodiesel, i.e. a mixture of monoalkyl esters of long chain fatty acids derived from renewable biological sources such as vegetable oils has in recent years emerged as an alternative fuel for transportation sector. The conventional method of producing biodiesel is through homogeneous catalytic transesterification; however, increased production costs associated with downstream purification steps have led to the development of more cost-effective and environmental friendly technologies. These advanced production technologies involve heterogeneous or enzymatic catalysts to produce biodiesel, as well as no catalysts in supercritical conditions. Heterogeneous catalytic systems can ease the separation of biodiesel from the reaction mixture along with the possibility of catalyst recovery, potentially leading to lower production costs; enzymatic catalysts give the same advantages, but transesterification can be carried out in milder conditions and with a wider range of feedstocks. Biodiesel synthesis in supercritical conditions composes another alternative to conventional methods due to higher reaction rates, shorter reaction times, and simpler biodiesel separation steps. Nevertheless, mass transfer limitations caused by diffusion problems between phases represent an hindrance for future establishment of these technologies, calling for the development of novel methods to intensify the process. These process intensification technologies include ultrasound irradiation, microwave heating, use of co-solvents, and membrane reactors. The main focus of this review is to discuss recent advances as regards to biodiesel production technologies, devoting a special attention to the use of novel catalysts, diversified feedstocks, besides an analysis of main operational parameters of transesterification processes.

面向环境应用的超重力反应器强化技术: 从理论到工业化

Sour gaseous pollutants released from the industrial tail or flue gas are the key source leading to serious environmental pollution. To meet the newly national regulation of the ultra-low emission limitation control of those sour gaseous pollutants in China, a new process intensification technology based on the high-gravity reactor(HGR)was proposed. The intensification principles and routes of the high-gravity reactor for sour gas separation by reactive absorption were elucidated and verified from lab scale to fully industrial scale. The higher selectivity of removal of SO2, H2S and CO2 from acidic gas mixtures could be realized by high-gravity technology using its advantages of intensifying mass transfer by orders of magnitude as well as the ultra-short residence time. Thus the ultra-low emission of sulfide was guaranteed by using HGR technology. A three-in-one scale-up method, i.e. scientific experiments+mechanism model at microscale+CFD simulation at macroscale of HGR was proposed and verified by industrialization practice. The largest scale high-gravity reactor(rotor diameter 3.5 m, casing diameter 5 m, capacity for gas flowrate 20×104 Nm3/h)in the world was developed and successfully implemented in the industrialization application of desulfurization. This breakthrough technology of process intensification has been now widely accepted and applied in industries for removing SO2 from tail gas and H2S from petroleum or natural gases, as well as CO2 capture from flue gas of power plants, etc. The case studies of them were reviewed in this work.

Research Progress of High Gravity Technology and its Application Prospect in Metallurgical Extraction Reaction

High gravity technology is an efficient process intensification technology. Its applications in the chemical, materials and other industries have been relatively mature. The basic principles, characteristics and development of this technology are firstly summarized in this paper. And then, its basic theory researches and engineering applications are comprehensively analyzed. Finally, aiming at the liquid extraction problems in metallurgy industry, the application prospects and problems to be solved were put forward.

Advances in solid-catalytic and non-catalytic technologies for biodiesel production

The insecure supply of fossil fuel coerces the scientific society to keep a vision to boost investments in the renewable energy sector. Among the many renewable fuels currently available around the world, biodiesel offers an immediate impact in our energy. In fact, a huge interest in related research indicates a promising future for the biodiesel technology. Heterogeneous catalyzed production of biodiesel has emerged as a preferred route as it is environmentally benign needs no water washing and product separation is much easier. The number of well-defined catalyst complexes that are able to catalyze transesterification reactions efficiently has been significantly expanded in recent years. The activity of catalysts, specifically in application to solid acid/base catalyst in transesterification reaction depends on their structure, strength of basicity/acidity, surface area as well as the stability of catalyst. There are various process intensification technologies based on the use of alternate energy sources such as ultrasound and microwave. The latest advances in research and development related to biodiesel production is represented by non-catalytic supercritical method and focussed exclusively on these processes as forthcoming transesterification processes. The latest developments in this field featuring highly active catalyst complexes are outlined in this review. The knowledge of more extensive research on advances in biofuels will allow a deeper insight into the mechanism of these technologies toward meeting the critical energy challenges in future.

GTL FPSO—An Alternative Solution to Offshore Stranded Gas

Summary Sustained and increasing world energy demands have led to very high oil prices. In parallel, there has been a significant increase in interest in economic and environmentally sensitive solutions for the monetization of remote, stranded gas offshore. Current global natural-gas reserves total approximately 6,100 Tcf, according to US Energy Information Administration estimates. Roughly one-half of these reserves are considered to be stranded gas that is uneconomical for market delivery because of the remote location of potential markets, the lack of economic transportation and infrastructure, or the lack of conversion technology. Such regions with significant stranded-gas reserves include Northern Australia, Vietnam, and Indonesia. Gas-to-liquids (GTL) floating production, storage, and offloading (FPSO) offers an attractive new solution to monetize these remote, offshore stranded-gas fields. Products of the GTL process are clean transportation fuels ranging from diesel to jet fuel that can be readily used in the existing energy infrastructure. Although this option was considered in the past by Syntroleum and Statoil in mid-2000, a subsequent examination of this option is warranted because of recent advances in both GTL and FPSO technology. New GTL commercial plants have recently begun production in Qatar, using technologies by Sasol and Shell with the latest advances in process technologies and catalysts. Membrane- and process-intensification technologies show considerable promise in making GTL an attractive option in the future. The newly built oil-FPSO units (at Pazflor and Agbami) instill confidence that large oil- and gas-processing operations can be performed safely and economically on an FPSO unit. A feasibility study has been completed recently as part of a multiyear development program to acquire the basic technology and engineering for GTL FPSO. An assessment was made on the technical feasibility of commercial-scale and near-commercial-scale technologies, and a preliminary design concept of the GTL process was produced for the topside. This study used technologies that best met the needs of the FPSO application and the corresponding preliminary design concept of the hull to support the topside GTL process. Additionally, preliminary market analysis was performed to better define the scope of GTL products to be produced. Economic analysis was performed to identify the major cost factors and understand their sensitivity on project economics. The results of this feasibility study to date suggest that this GTL-FPSO design concept is technically feasible. Its clean fuel and chemical feedstock would be attractive to the market, and the design concept is economically competitive within the range of the current project-cost factors. Future work will be directed at developing a more-definitive process, hull design, and project economics, and will bring commercial realization of this innovative approach to monetizing offshore stranded-gas fields.

Design and Control of Thermally-Coupled Reactive Distillation System for Esterification of an Alcohol Mixture Containing n-Amyl Alcohol and n-Hexanol

Semiconductor and pharmaceutical industries often produce waste alcohol mixtures. This study discusses a reactive distillation process of a mixed alcohol feed containing n-amyl alcohol and n-hexanol to react with acetic acid to produce useful esters. In an earlier paper (Lee et al. Ind. Eng. Chem. Res. 2009 48, 7186–7204), optimal design of the same Type-III mixed-alcohol reactive distillation process containing n-butanol and n-amyl alcohol was developed. In that paper, the indirect sequence containing a reactive distillation column with heavier amyl acetate bottom product and a second column to produce butyl acetate gives the lowest total annual cost. In this study, with different mixed alcohol feed (although of the same reaction type), it is found that an alternative direct sequence design is much more economically favorable with 34% reduction in total annual cost as compared to the indirect sequence. The reason for the seemingly contradictory results can be explained by differences in relative volatilities of binary pairs in the stripping sections of the reactive distillation towers. Process intensification technology is also attempted to devise a thermally coupled reactive distillation configuration to further save 13% of the operating energy. The overall control strategy using tray temperatures is also proposed to maintain high-purity products despite various disturbances.

Cyclic operation of trickle bed reactors: A review

Familiarized with the steady state behavior and advantages of the trickle bed reactors (TBR), for the past two decades, researchers and process engineers are continuously exploring the unsteady state hydrodynamics of periodically (or cyclic) operated trickle bed reactors to extract even more from its efficiency and performance. Despite its complicated nonlinear behavior that attributes to the process control safety at the commercial scale, cyclic operation of TBR is a promising process intensification technology that has immense potential for implementation on industrial TBR. In this paper, we have summarized and reviewed the research and progresses made in recent years on cyclic operation of TBR and potential applications of various mode of its operation. Several issues associated with its hydrodynamics scale-up and designs have been discussed with an emphasis on shock wave attenuation that arises during flow modulation.

Characterization of tributyrin hydrolysis by immobilized lipase on woolen cloth using conventional batch and novel spinning cloth disc reactors

Optimal loading and operating conditions for a new, superior immobilization of amano lipase from Pseudomonas fluorescens on woolen cloth were determined. The optimal enzyme loading was 46.8mggdrycloth−1 with activity of 200U. A batch reactor was used to characterize process conditions important to industrial application of the wool immobilized lipase. The optimal pH for immobilized lipase in tributyrin hydrolysis was 7, slightly lower than that of free lipase (pH 8). The optimal temperature for both free and immobilized lipase was 45°C. The immobilized lipase was more stable to reuse than some other lipase immobilizations, maintaining 85% of its activity after 6 long term runs and 75.8% of the original activity after storage of 40 weeks at 4°C. The thermal stability of lipase was improved by 2.4 times after immobilization. The thermal deactivation rate of immobilized lipase followed the Arrhenius law with Ed=199kJmol−1. The Michaelis–Menten constant (Km) of the lipase increased from 1.63mM to 4.48mM after immobilization. The immobilized lipase was also successfully applied for tributyrin hydrolysis in a novel enzyme process intensification technology – the spinning cloth disc reactor (SCDR): conversion increased by around 13% under similar conditions compared to a conventional batch stirred tank reactor. The SCDR is therefore key to exploiting the advantages of the wool immobilized lipase developed in this work.

Novel applications of dividing‐wall column technology to biofuel production processes

AbstractBiofuels enjoy nowadays increased public and scientific attention, driven by key factors such as volatile oil price, the need for increased energy security, and concerns over greenhouse gas emissions from fossil fuels. However, in order to make biofuels a competitive alternative, the cost of production has to be significantly reduced by using enhanced process technologies. Distillation is heavily involved in the production processes of biofuels—taking the blame for the high energy requirements that have a negative impact on the operating costs. Dividing‐wall column (DWC) is one of the best examples of proven industrial process intensification technology in distillation, as it allows significantly lower investment and operating costs while also reducing the number of equipment units and the carbon footprint.This work presents an overview of novel applications using the DWC technology in the production of the most important biofuels, by employing multi‐component separations, azeotropic, extractive or reactive distillation in a DWC: enhanced methanol recovery and glycerol separation in biodiesel production, synthesis of fatty acid methyl esters and dimethyl ether (DME) by reactive distillation, integrated DME purification and methanol or CO2 recovery in the dimethyl ether process, as well as bioethanol concentration and dehydration. The industrially relevant case studies presented here show that significant energy savings are possible (ranging from ∼20 to 60%) while simplifying the processes by using less equipment that requires a lower plant footprint. Remarkably, in most cases there is also the possibility of revamping existing plants producing biofuels, and thus reusing the already available equipment. © 2013 Society of Chemical Industry

The case for the photocatalytic spinning disc reactor as a process intensification technology: Comparison to an annular reactor for the degradation of methylene blue

A spinning disc reactor was investigated as a process intensification technology for photocatalysis and compared with a conventional annular reactor. It was found that the average photonic efficiency achieved in the SDR was three times larger than the maximum photonic efficiency achieved in the annular reactor, 0.19±0.08% versus 0.062±0.009%, indicating that the SDR is significantly more efficient at utilising the incoming light. Similarly, the average volumetric rate of reaction for the SDR was an order of magnitude larger than that of the annular reactor, 3.6±1.5×10−4molm−3s−1 versus 0.13±0.02×10−4molm−3s−1, due to the significantly smaller volume in the SDR. However, the average surface rate of reaction is more useful for comparison in an immobilised catalyst system. In the SDR, the initial surface rate of reaction was approximately the same (within the margin of error) as the photocatalytic reaction in the annular reactor. This suggests that both reactors exhibit the same rate limiting step. Given the significantly higher mass transfer rate in the SDR over the annular reactor, it is likely that the rate limiting step is either the adsorption of oxygen onto the catalyst or the electron transfer from the catalyst to the oxygen, often found to be the rate limiting step in photocatalytic reactions. However, the maximum surface rate of reaction achieved in the SDR (at a flow rate of 15mLs−1) was two times larger than the maximum reaction achieved in the annular reactor — this suggests that at this condition the rate limiting step is being overcome, and that when operated at this condition the photocatalytic SDR is performing as a process intensification technology.

The spinning cloth disc reactor for immobilized enzymes: A new process intensification technology for enzymatic reactions

The spinning cloth disc reactor (SCDR) is an innovative enzyme reaction intensification technology. Based on spinning disc technology, the SCDR uses centrifugal forces to allow an even spread of a thin film across a spinning horizontal disc which holds a cloth with immobilized enzyme. This geometry promotes accelerated reactions due to high mass transfer rates and rapid mixing. Here, the SCDR has been benchmarked against a conventional batch stirred tank reactor (BSTR) using tributyrin emulsion hydrolysis as a model reaction and lipase immobilized on woolen cloth as the biocatalyst. Reaction intensification has been shown to occur: the conversion in the SCDR was significantly higher than that in a conventional BSTR under comparable conditions. Spinning speed and flow rate control reaction rate and conversion: conversion increased nearly 7% on average as the flow rate rose from 2 to 5mLs−1 and the highest conversion (72.1%) occurred at 400rpm. A Ping Pong Bi Bi kinetic model fitted reaction progress data well. The immobilized lipase showed excellent stability to repeat reactions in the SCDR: 80% of the original activity was retained after 15 consecutive runs. The robustness of the SCDR to industrially relevant feeds was also demonstrated through successful hydrolysis of different vegetable oils at reaction rates 5 times higher than other reactors in the literature. Overall, the above results indicate that the SCDR is an innovative, superior and robust technology for enhancing enzyme reactions, taking enzyme reactors beyond the current state-of-the-art. This concept can readily be extended to other enzyme-catalyzed reactions, where enhanced mass transfer and enzyme stability is needed.

Updated Applications of Flow Chemistry in Pharmaceutical Synthesis

As a further-developing process intensification technology, flow chemistry has achieved a striking development either in academic or industrial area in the past decade. Updated applications of flow chemistry in pharmaceutical synthesis are overviewed. Compared with its early research and development (RD microreactor; microreaction technology; API synthesis; multistep flow synthesis; process catego- rization

Simulation of Cumene Synthesis by Suspension Catalytic Distillation

This paper deals with alkylation of benzene with propylene to produce cumene by Suspension Catalytic Distillation (SCD) which, as a new technology of process intensification, has been developed from traditional catalytic distillation. In this SCD process, the supported heteropolyacid catalysts are suspended inside the liquid phase on the column tray and flow with them, while in traditional catalytic distillation the catalyst pellets are generally fixed somewhere inside the column. SCD processes have been investigated for alkylation reaction of benzene with olefins in laboratorial scale. A pilot plant of SCD process for cumene synthesis had been run for several months. It has shown more advantageous characteristics for cumene synthesis compared with conventional process consisting of a reactor followed by distillation train. Based on experimental data and the reactive kinetic parameters of cumene synthesis using the supported heteropolyacid catalysts, numerical simulation of SCD process of the pilot plant was performed by an equilibrium stage model to study the effects of operation conditions on the process performance. The simulation results could agree, to a great extent, with the data acquired from the pilot plant experiment.

Window of opportunity – potential of increase in profitability using modular compact plants and micro-reactor based flow processing

Recently, much focus has been given to a new type of chemical production plant, with the aim of a much faster time-to-market (“50% idea”) and better cash-flow revenue. The main enabling technology is to have the plants pre-manufactured and assembled by a modular construction and to use innovative, smart-scale processing and apparatus technology, in order to achieve a compact overall plant footprint. Focal points in such technology are on the one hand, flow processing, with micro process technology as a cutting-edge cornerstone, and on the other hand, the container framework. Yet, other process-intensified technologies are suitable as well such as milli-flow or upgraded batch technologies. Finally, process robustness and short-time applicability make the decision. In this paper, for the first time, a CAPEX and OPEX analysis of the new plant technology is done, at the example of the Evotrainer production platform. This platform is pre-manufactured in serial and provides all the utilities needed around the reactor and e.g., separator to be tailored and inserted. The unit-operational modularization, with respective definition of interfaces, was developed further to a so-called functional modularization, where different cabinets with pre-defined functions and equipment are proposed. Three virtual microreactor applications were used and stand as model-based scenarios for market applications in bulk chemistry, fine chemistry and pharmacy. It is shown, in many facets, that the Evotrainer infrastructure based plants indeed have a faster payback and higher earnings as compared to conventional technology, particularly when serving high-priced markets such as pharmaceutical applications. Further, the combination with novel chemical routes or novel processing (Novel Process Windows) is advantageous. Micro process technology is one of the key enablers and was taken here, since the dataset of such technology was readily available to the authors due to past research efforts and there is some general belief in the combination to the so-called “Future Factories”. Yet, it stands also for any other process intensification technology which can achieve the same performance level and which is able to satisfy the needs of a producing industry.

The spinning disk reactor: an example of a process intensification technology for polymers and particles

This review introduces the spinning disk reactor and emphasises its suitability for all aspects of polymer chemistry. The literature reviewed includes university theses, as well as key patent and openly published literature; it is not an exhaustive collation of the literature to date. The spinning disk reactor (SDR) is introduced in the context of process intensification (PI). The SDR is the apparatus which has the best mass and heat transfer characteristics of all typical chemical reactor types, while being flexible and economical (material and energy). It is inherently safer than traditional stirred tank reactors. The theory essential for the practical use of SDR is briefly summarised to emphasise the ease with which laboratory SDR experiments can be scaled up to produce commercial quantities. The use of SDR to produce well defined filler particles with simple (e.g. BaSO4) and reactive (Ag) precipitation reactions is discussed. In order to emphasise the general and facile utility of the SDR in all aspects of polymer chemistry, the literature available for polymer analogue (modification, e.g. hydrogenation) reactions is presented. Further, step-growth- (polyurethanes), chain-growth- (e.g. polystyrene) and condensation (e.g. polyesters) polymerisations are examined. UV-activated bulk, emulsion and solution polymerisations and co-polymerisations (acrylates) are also described. Some of the experiments described were carried out in the senior author's laboratory and as well as critically reviewing the available literature, a possible direction for future work is indicated.

メタン改質プロセス強化(PI)技術としてのヒートコンバインド型反応システム

メタン改質プロセス強化(PI)技術としてのヒートコンバインド型反応システム

Green chemistry and engineering: a practical design approach

Green chemistry and engineering: a practical design approach