Coffee is the beverage resulting from the infusion of roasted and ground seeds of the coffee fruit. It is one of the most commercialized products in the world and represents a high interest agro-industrial product in Mexico. The demand for this product has grown in great measure in the last decade, thus it is becoming more important to make environmental and energetic evaluations of its manufacturing process. In this sense, life cycle assessment (LCA) is a useful tool for the purposes of this study, as it quantifies the wake of environmental impacts associated to the production and supply chain from its inputs and outputs of the product system. Therefore, the impact categories studied were carbon, energetic, and water footprints. The cultivation phase led to global contributions between 61% and 67% in magnitude for energy and carbon footprints, respectively; meanwhile, the coffee benefit process was the phase with the most contributions to the water footprint (54%). The residual biomass from the product system used as the energy supply within the coffee drying sub-phase represented energy savings of around 41% in comparison to the use of conventional fossil fuels, thus reducing the global impact associated to the system’s product.

The appropriate selection of treatment or final disposal for municipal solid waste generated by a population depends on multiple characteristics; decision-making becomes a challenge for those responsible for its integral management. Therefore, the objective of this research was to evaluate multi-scenarios of valorisation of the organic fraction of municipal solid waste. The methodology used included a sample of 421 houses to determine the generation and composition of the aforementioned municipal solid waste; this data served as input to be able to design four treatment and final disposal scenarios: current situation, composting, anaerobic digestion and landfill. The parameters of humidity, biochemical methane potential and biogas were used. In addition, organic fraction variability and treatment cost were considered. Data analysis included design of experiments with the uncertainty coefficient and predictive equations. The results showed that composting was the scenario that presented the highest coefficient of determination and therefore it would be the best choice to fit the particular conditions of the localities. It is concluded that this applied methodology can be used as a tool in the decision-making process regarding the valorisation of the organic fraction of municipal solid waste and can be replicated at a national and international level.

In the last few years, pineapple (Ananas comosus) has grown to be considered one of the most important fruits worldwide due to its high production and consumption. However, inadequate disposal of the waste it generates, which represents up to 67% of its total weight, can have environmental impacts. Therefore, this study focuses on the degradation of organic waste produced in the industrialized processing of pineapple waste (rinds, crowns and cores), which undergo a process of vermicomposting at a laboratory level. The methodology used included the pre-composting process and vermicomposting through Californian red worms using mixes tested in three different proportions of pineapple waste (PR) and load material (LM) made up of vegetable waste and eggshells. Testing revealed that the pre-composting process for this waste was feasible as a first stage of the degradation process; the characteristics of the pre-composted material allowed a favorable adaptation for both the worms and general degradation. It also showed efficiencies in the removal of organic carbon between 36.40% and 45.78%. Results also showed the total nitrogen content remained between 1.2% and 2.2% and the carbon/nitrogen relation (C/N) had values under 20 as required for high-quality vermicompost.

Abstract:The energy market is diversifying, allowing for the development of biofuels that seek to reduce environmental impact and be energetically competitive with conventional fuels. One of the aforementioned biofuels is the biodiesel that is produced from the oil extracted from the seeds of Jatropha curcas L. This research uses life cycle analysis (LCA) tool to analyze the following environmental impacts associated with its production: energy, water footprint, carbon footprint, mineral resource depletion, fossil resource depletion, terrestrial ecotoxicity, and human toxicity. The following stages were evaluated: (i) cultivation, (ii) the extraction of oil, and (iii) the biodiesel manufacturing process. The results showed that the overall process has an accumulated energy demand of 37.9 MJ/kg biodiesel, and generates 2.16 kg CO 2 eq. of greenhouse gases (GHG) per kg of biofuel. The cultivation stage had the greatest contribution towards its energy and carbon footprints, taking up 45% and 60%, respectively. However, considering the energy valorization of the coproducts that are generated in the agricultural and extraction stages for self-consumption into the product system, both categories of impact mentioned above were reduced by 35% and 41%, respectively.

As vermicomposting has become a viable alternative for the valorization of organic waste; the objectives of this research were to (1) assess the feasibility of said process for corn cob waste (corn cobs and corn husks) and (2) evaluate the operation conditions for the biodegradation of different mixtures with load material (LM). LM did not include animal excreta as a nitrogen source, a practice widely used in a range of studies. The experiment consisted of an initial phase of pre-composting in order to obtain a partially stabilized substrate. Subsequently, four separate mixtures were made consisting of corn cob waste mixed with consistent load material (LM) containing vegetable waste and eggshells (CR, M1, M2, M3) to obtain a balance substrate able to facilitate degradation using Eisenia fetida earthworms. The following parameters were analyzed during the control process: temperature, pH, humidity, organic material (OM), total organic carbon (TOC), total nitrogen (TN) and carbon/nitrogen (C/N) ratio. The analysis of the final values of the stabilized mixtures showed that vermicomposting is indeed a feasible alternative for the degradation of corn cob waste for use as a soil improver.