No abstract

Biogas technology represents an option to enhance sustainable energy use in developing nations particularly in the rural context. However, the production and use of biogas could also take place in urban settings in these countries with potential benefits for their sustainability. The present work introduces a set of nine indicators in the economic, social and environmental sustainability dimensions for assessing the impact of a small-scale biogas plant on the energy sustainability of a restaurant located in Mexico City. Indicators were evaluated before (base scenario) and after (biogas scenario) biogas plant installation and then they were linearly normalized using a scale between 0 and 1 corresponding to a growing level of energy sustainability. Economic dimension indicators averaged 0.67 in the base scenario and 0.68 in the biogas scenario; those of the social dimension, 0.52 and 0.54; and those of the environmental dimension, 0.17 and 0.49, respectively. Results indicate a positive impact of biogas plant on restaurant energy sustainability. These indicators provide objective elements to examine in detail biogas contributions in strengthening energy sustainability of cities in developing countries.

Simazine degradation by mixed microbial cultures was carried out in biological reactors with tepojal and sepiolite beads. The inoculum used is derived from a biotechnological product applied to plant roots, which contains mixed microbial cultures. This inoculum presented a stable adherence to the microorganism support throughout the experiment. In this research, the supports were evaluated in relation to both biofilm formation and simazine removal. For this study, hydraulic and mass starting-up parameters were established for simazine degradation and for the use of these reactors in the two types of supports. Tepojal had never been used before as a microbial support in any previous research paper. Tepojal demonstrated to be more efficient than sepiolite. Statistical analysis was done for the relationship among the parameters of chemical oxygen demand, colony formation units, total suspended solids, and volatile suspended solids. Water Environ. Res., 83, 274 (2011).