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Steam reforming of ethanol (SRE) on a Ni/Al2O3 catalyst was studied. The effects of the operating conditions and catalyst nature on the course of reaction were evaluated. Hydrogen was generated in the temperature range between 100 and 600°C. A mechanism was used to explain the reaction pathways. A commercial hydrotalcite‐like sorbent arranged in a multilayer pattern of catalyst and sorbent was used for CO2‐uptake to enhance hydrogen production. The concept of sorption enhanced reaction process on SRE is illustrated by the operation of catalyst and CO2‐sorbent at 400°C. A lower flow rate regime and multilayer pattern system enhances hydrogen production in the initial breakthrough periods. CO appears in traces in the product gas stream. © 2011 Canadian Society for Chemical Engineering

A thermodynamic analysis is performed with a Gibbs free energy minimization method to compare the conventional steam reforming of ethanol (SRE) process and sorption-enhanced SRE (SE-SRE) with three different sorbents, namely, CaO, Li 2 ZrO 3 , and hydrotalcite-like compounds (HTlc). As a result, the use of a CO 2 adsorbent can enhance the hydrogen yield and provide a lower CO content in the product gas at the same time. The best performance of SE-SRE is found to be at 500°C with an HTlc sorbent. Nearly 6 moles hydrogen per mole ethanol can be produced, when the CO content in the vent stream is less than 10 ppm, so that the hydrogen produced via SE-SRE with HTlc sorbents can be directly used for fuel cells. Higher pressures do not favor the overall SE-SRE process due to lower yielding of hydrogen, although CO 2 adsorption is enhanced.

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Climate Change and its effects in water scarcity has become an important challenge for cities with water management problems. These problems require an integral planning of the city, which can be supported by optimization. The main goal of the research is to provide a regional optimization model for water networks, including new treatment options. The model is formulated as a multi objective mixed integer programming problem, focused on environmental and economic impact of the network, minimizing water extracted from natural sources and total cost. The formulation is developed with the goal programming methodology. The model covers a complete existing city scale water network, including 4 different options of water reuse within the city: drinking water, fresh water, irrigation, and discharge in natural courses. The case study is Santiago, capital of Chile, which is the political, economic, and insti tutional center of Chile. If both objective functions have equal importance to configure the solution, the following ideas characterize the optimal water network: (i) it is more environmentally and economically convenient to reuse water within the network rather than recycling water to the natural source; (ii) the reuse of water is preferred in the form of irrigation and drinking qualities rather than industrial qualities to reduce transport costs, and (iii) the modification of the current treatment plants is preferred, because of the high cost of installation of new plants. An environmental and cost effective solution for Santiago, Chile, can reduce the source water extraction in 35.7%. The model can be implemented in other contexts, providing orientations to decision makers so as to plan city scale water networks with simultaneous environmental and economic considerations.

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An Eco-Industrial Park (EIP) is a community of businesses that seeks to reduce the global impact by sharing material. The connections among the industrial participants within this park improve the environmental performance of the industrial network. However, the connectivity also propagates failures. This risk is an important point of criticism and a barrier to industrial plants when evaluate their integration to an EIP. This paper proposes an indicator to follow the resilience of an EIP so as to improve the security of the whole system, considering the dynamic of the participants to endure a disruptive event. This metric could be used by decision-makers in order to include the resilience in the design phase of an EIP. Solving these security problems would expand the set of experiences of cleaner production, facilitating the integration of industrial processes. The proposed resilience indicator is based on two main characteristics of an industrial network: the number of connections among participants, and the capacity of each flow to change its magnitude when a participant suddenly stops sharing flows within the park. A network is separated in independent layers to quantify its flexibility when substituting flows. Each layer includes a single shared material. The resilience of a multi-layer park is then calculated as a weighted summation. This indicator is applied over two illustrative cases to study: Kalundborg, in Denmark; and Ulsan, in South Korea. These applications show consistent results when compared with reality. Although the proposed resilience indicator has been developed for material networks, it can be adapted to heat integration networks. In this case, special attention should be payed to physical constraints as minimal temperature gradients.