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This work aims to develop a stationary phenomenological model of an industrial steam reforming unit. Unlike the usual approach in literature, the combustion reactions at the furnace are described t...

Catalyzed chemical reactions inside tubular reactors play a key role in steam methane reforming process, as they define the temperature and composition profiles of the reformer and, consequently, its efficiency. Although the kinetic modeling of reforming reactions has already been widely discussed, studies that carry out the comparison between kinetic reform models are still scarce. In this context, this work aims to evaluate the influence of different kinetics on the stationary behavior of industrial reformer. The kinetic models of Singh and Saraf (1979), Numaguchi and Kikuchi (1988), Xu and Froment (1989a), and Hou and Hughes (2001) were analyzed and compared with each other. All models describe the reformer satisfactorily with relative deviations around 3.5% compared to experimental and literature data. The results show that the simplest kinetic models present advantages compared to traditional models, such as Xu and Froment (1989a), which is widely used without any prior analysis.

The techno-economic feasibility of three biogas utilization processes was assessed through computer simulations on commercial process simulator Aspen HYSYS: HPC (biogas to methanol), BioCH4 (biogas to biomethane) and CHP (biogas to heat & electricity). The last two processes are already used commercially with the aid of subsidy policies. The economic analysis indicates that, without these policies, none of these attain economic self-sustainability due to high overall manufacturing costs. The estimated minimum support cost (MSCs) were 108, 62 and 109 €/MWh for the HPC, BioCH4 and CHP processes, respectively. The model could explain currently practised government subsidies in Italy and Germany. It was seen that the newly proposed HPC process is economically comparable to the traditional CHP process. Therefore, the HPC process is a possible alternative to biogas usage. A support policy was proposed: 50, 66, 158 and 148 €/MWh for available heat, methane, electricity and methanol (respectively); the proposed energy policy results in a 10% OpEx rate of return for any of the processes, thus avoiding a disparity in the production of different products.

In this work (part of a series in which different biomass conversion routes are studied) a novel coupling between gasification and pyrolysis is described: by means of a design parameter (α) biomass is distributed between these two operations. In order to characterize the quality of the syngas produced, simulations are performed with a gasification / pyrolysis simulator, GASDS. Profiles were obtained for oxygen consumption, together with bio-char, syngas and steam production as a function of α. In a further work, an economic analysis shall define optimal design conditions.

This paper examines the physical environment, institutional structure and objectives, interpersonal dynamics, and shortcomings of existing treatment programs, especially the counseling process, at the State Prison of Southern Michigan at Jackson (population greater than 5,000) with a view to providing a perspective on the difficulties in creating and sustaining a genuine learning situation in such an environment. Next, the evolution and adaptation of an innovative multidisciplinary four-year Bachelor of General Studies Degree program for such a setting using a variety of instructional formats (workshops, conferences, television) is described. Provisions for specialization, and student involvement in and reaction to the program and ways of dealing with reading, writing and math skill deficiency are discussed. Next, a reform proposal that recognizes the fallacy of rehabilitation in the course of punishment is suggested. Lastly, the role of the larger society in fostering the alienation that leads to crime i...