Antonio Amelio

Guidelines based on life cycle assessment for solvent selection during the process design and evaluation of treatment alternatives

The aim of this paper is to develop guidelines in order to assist in decision making with respect to treatment options of waste solvents, and more importantly for the choice of solvent in the design of the process a priori, from an environmental point of view based on the composition of a mixture. Life cycle assessment (LCA) was used to evaluate two treatment alternatives: continuous distillation and incineration. The software Ecosolvent® v.1.0.1 was used to perform the LCA, considering two scenarios (the best and worst scenarios) and five environmental indicators: Eco-indicator 99, UBP-97, global warming potential, cumulative energy demand and CO2-balance. From the results, it can be concluded that the environmental impact originating from the production of the solvents is the main issue to consider for the selection of distillation or incineration as the treatment method during the process design. In general, those solvents with a low impact during their production stage were found to be candidates for incineration. Moreover, those compounds that yield a great environmental burden during the production step should be always recovered in order to minimize the total impact. A series of charts is presented as guidelines to select the most environmentally favorable alternative for mixtures of solvents, and to select which solvent to use considering the environmental effects that are produced. Regarding the information given by the different indicators, it was observed that all the studied indicators lead to the same conclusions for the evaluated mixtures with some exceptions for UBP-97.

Pervaporation membrane reactors: Biomass conversion into alcohols

The use and production of bioalcohols, butanol and ethanol, are described in this chapter. In the first part, the state of art of their production is explained, as well as the reaction pathways, the different reaction geometries, and the importance of the sources as raw material. The possibility of using pervaporation (PV) coupled with a conversion reactor is shown. The use of two membranes in series (hydrophobic–hydrophilic) allows a high-quality product to be produced. A brief revision of the current performance of the membrane used is described, which allows us to understand the direction in which research has to go to improve this technology. A comparison of PV with current technologies used to purify these alcohols is reported as well. The current state of production for these two alcohols is illustrated, along with future perspectives.

Conceptual model-based design and environmental evaluation of waste solvent technologies: Application to the separation of the mixture acetone-water

ABSTRACT In this paper, two waste solvent technologies are presented as alternatives to the disposal of spent acetone-water mixtures. In the first alternative, a batch rectifier is used to concentrate the waste in order to obtain a distillate with a higher calorific value, which is then sent to off-site incineration either in a cement kiln or in a conventional waste solvent incinerator. The second alternative is a hybrid process composed by a batch rectifier and a pervaporation unit that processes in batchwise mode the first cut from the distillation task to obtain a dehydrated solvent. Here, four scenarios are considered, comprising two kinds of membrane materials and two different vacuum systems. For each alternative, the conceptual design was carried out with the aid of conceptual models of the unit operations involved. Quasi-optimal values for design and operation variables were used as input data to perform an economical and an environmental assessment of each alternative. The economic analysis suggests that the hybrid process is the best alternative given that the replacement cost of fresh solvent (about 850 U

Simulation and environmental evaluation of process design: Distillation vs. hybrid distillation–pervaporation for methanol/tetrahydrofuran separation

S/ton) is considered as a credit value. From the environmental analysis with life cycle assessment, two main conclusions can be drawn: i) the use of the distillate as an alternative fuel in a cement kiln leads to a reduction in emissions that is relevant for the categories related to human health and ecosystem quality; and ii) in terms of resource depletion, the hybrid process distillation/pervaporation with the ceramic membrane HybSi (Pervatech) shows the lowest impact due to the solvent recovery.