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Efficient processes save natural resources, e.g. chemicals, energy carriers. The Extractive Heterogeneous Azeotropic Distillation (EHAD) is an efficient, novel process for the separation of highly non-ideal liquid mixtures. On the one hand, it consumes less energy than any other separation process and on the other hand the separated compounds of highly non-ideal mixtures can be reused. The EHAD contributes to the saving of natural resources and sustainability. The efficiency of the EHAD is presented on the separation of three highly non-ideal quaternary mixtures of fine chemistry and printing company origins. In this work, the comparison of the efficiency of different separation technologies are compared based on their energy consumptions. It is concluded that the EHAD based separation technology needs the least energy among the investigated alternatives and also enables the recovery and reuse of precious organic compounds.

Separation of highly non-ideal mixtures with the use of extractive heterogeneous-azeotropic distillation (EHAD) has been successful in the last few years. In contrasts, most researches have focused on mixtures with containing minimal boiling homoazeotropes. Despite the fact that maximum boiling azeotropes are fewer in numbers it is important to examine if the use of EHAD method is viable. It is important to note that the EHAD method does not exclude maximum boiling azeotropes despite the fact that these types of azeotropes can not be heterogeneous. In the fine chemical industry, large amounts of used solvent have to be disposed, in many cases with incineration. Because of the high cost it is advisable to concentrate and dehydrate of the liquid wastes. The work is motivated by an industrial environmental problem, which is concentration and dehydration of used, waste solvent contains maximal boiling azeotrope in one step with EHAD. The separation of highly non-ideal Water-Acetone-Chloroform-Methanol quaternary mixture is investigated and optimized in professional flowsheet environment. The aim is to reach as clear as possible bottom product in water compound in order to few distillate product has to be burned. Two slightly different constructions of separations are examined. It can be concluded the computer simulations and experimental verification are proved the separation efficiency of EHAD in first case of maximal boiling azeotrope mixture.

Biofuel production is an ever current topic, as bioethanol and biobutanol have a great potential to partially or completely replace fossil fuels in the automotive industry due to their attractive characteristics. They are usually produced by fermentation resulting in a highly diluted mixture, which poses a challenge to the downstream processing and the production of pure alcohols. In the course of this work, conventional separation systems of simple, extractive and heteroazeotropic distillation are compared with hybrid distillation-pervaporation systems for the separation of a ternary ethanol-n-butanol-water (EBW) mixture. Pervaporation (PV) is studied as an option for the final dehydration of the alcohol-water mixtures due to its great industrial potential in the separation of azeotropes. Simulations are carried out in ChemCAD® flowsheeting software, and the process alternatives are evaluated in an economic point of view, revealing the potentials and drawbacks of PV in a complex separation task.

The dividing wall columns have they renascence, however, there is lack of comprehensive investigation of column with upper and lower positioned walls. Previous work presented the energy efficiencies of dividing wall columns compared to common and energy integrated column structures. This paper presents a comprehensive study of controllability features based on frequency dependent controllability indices and their aggregation in the so called “desirability function”. Conventional distillation column sequences and dividing-wall columns are selected for the study. A total of six different distillation arrangements are considered separating three ternary alcohol mixtures with different eases of separation. Rigorous simulations are carried out using Aspen Plus and Aspen Dynamics. Linear state-space representations of the studies systems are obtained using the Control Design Interface. Frequency dependent controllability indices, MRI, CN and RGAno, are calculated by MATLAB. Based on open-loop responses, discrete frequencies are chosen to determine characteristic indices of the systems. Evaluation of the results is supported by the desirability function. The results show that the separated mixtures influence the controllability features. However, from the different results of our work, we select that if indirect separation structure is recommended, DWC with lower partition shows considerable enhancement in controllability properties.

The detrimental environmental effect of the CO2 emitted into the atmosphere is a well-known problem. To answer the challenges of environmental protection, University of Miskolc, Hungary, established a network called “Environmental carbon-dioxide partnership” (eco2p.eu) so that this organization contributes to The solution of the global warming problem, Storage of renewable energy, Production of materials on renewable basis. To complete these goals the CO2 can be the key molecule, the called platform molecule that is used for the solution of these challenges. The CO2 can be transformed to either formic acid, methanol or natural gas, methane. These molecules can be used for the storage and production of energy or other chemicals. Beside the technological aims there are significant management activities on macroeconomic level, too. The efficient use of the technological solutions at the fluctuating circumstances of the renewable energy production should be determined. The split ratio between energy storage and/or renewable material production is also a key issue for the macroeconomic studies.

Ethylene is one of the most important product in chemical industry, then it is required to produce ethylene in large quantity. The ethane-ethylene separation is achieved by high pressure cryogenic distillation in a rectification column. In this paper, an ethane-ethylene rectification column was investigated. At first, the parameters of the column were described, then with two process simulation software – UniSim Design and CHEMCAD –was used to simulate the model of the column. The purpose of the separation was to reach as much ethylene as possible in the overhead product. Therefore during the parametric examination, the aim was to achieve the greatest – even maximum – quantity and quality of the ethylene in the overhead product. In order to this goal, the influencing effects of the modification of reflux ratio and pressure was evaluated. In addition, changes in the column’s internal design (tray construction) was observed. Furthermore, this study examined the behavior of the system (particularly the ethylene mole fraction in the overhead product and the condenser’s heat flow) when feed’s temperature and mass flow changes.

The separation of homogeneous mixtures is an essential aspect of modern industrial processes that significantly relies on distillation operations. However, distillation has an elevated energy consumption and results in inefficiency in various cases. The non-ideal properties of certain mixtures render their separation unsuitable when employing a single distillation unit, increasing the necessary steps and energy requirements. Because of the relevant role of energy saving in sustainability, a systematic approach must be employed to select the most appropriate separation strategy and identify the operations that minimise energy requirements for product generation. This work employs a systematic approach that utilises residual curve maps to propose viable separation stages and determine the best separation sequence. Various separation strategies are identified via the P-graph framework, which identifies the n-best separation strategies and provides the designer with insightful information concerning the process and its performance. Such a methodology had been previously demonstrated for the separation of ternary mixtures; however, this work constitutes a first step in the development of a systematic approach for the separation of quaternary (or more complex) azeotropic mixtures. The range of separation options, including azeotropic distillation and extractive heterogeneous-azeotropic distillation, are identified by analysing the quaternary residual curves. The potential of this method is demonstrated through a case study involving a mixture of acetone, ethyl acetate, ethanol, and water. The initial set of structures comprises 37 alternative sequences for separation, out of which three interesting alternatives are discussed in detail. The case study demonstrates the potential of the method employed in assessing azeotropic distillation alternatives and facilitating informed decision-making for designers.

This work aims to propose a general data-driven plastic waste categorisation procedure that defines their recyclability based on classification into material recycling classes. The contamination in plastics, such as metal fillers or additives, is accumulated during the entire Life Cycle, which can be harmful to either mechanical or chemical recycling. The plastic polymers can also degrade during recycling due to weakened chemical bonds in the polymers. The diversity of plastic material types and products makes it necessary to use a data-driven quality-based definition of plastic waste properties to facilitate proper waste recycling and mitigation. This study demonstrates the use of Machine Learning tools that enable automated classification to analyse the plastic waste data and derive the indicators for plastic waste recyclability. Tree-based models such as the Decision Tree Model and Random Forest Algorithm are used as they produce interpretable if-then rules for plastic waste categorisation. The proposed method allows an analysis of the metal contamination and degradation data in a collection of plastic material samples or batches to derive a general categorisation rule for a polymer type – PE. The data-driven plastic categorisation could help in understanding the current waste practices and determining a proper recycling plan for local or even global plastic waste.