Bioenergy transition as a strategic mechanism to diversify energy sources in rural areas in Colombia

Received: February 1st, 2023 ; Accepted: May 27th, 2023 ; Published: October 14th, 2023 ; Correspondence: [email protected], [email protected] growth in population has resulted in an increase in the consumption of goods and services, which has led to a surge in waste generation and the use of fossil fuels. To mitigate the envi-ronmental issues associated with improper waste management and reduce greenhouse gas emissions from fossil fuels, residual organic matter can be used to produce bioenergy in the form of biogas and biomethane through anaerobic digestion (AD). These biofuels can act as substitutes for liquefied petroleum gas (LPG) and natural gas (NG) and can be utilized for power and heat generation. In Colombia, the current production of biogas is 4 MW, and the government aims to increase its utilization by promoting the inclusion of biogas and biomethane in the energy matrix through a supportive regulatory framework. Studies suggest that the theoretical energy potential of livestock waste in Colombia is estimated to be 2,673 MW, but the current technological conditions allow for the utilization of only 198 MW, with the pork sector contributing 34%. This study examines the legal context and the present state of biogas in the Colombian energy matrix, while exploring the potential of the Colombian pig farming sector for biogas production. The social, economic, and environmental barriers and opportunities faced by this sector in becoming an energy producer during the transition period are also identified. The findings suggest that biogas presents a sustainable energy solution for rural areas of Colombia where pig farming is a prominent economic activity. Biogas can replace traditional fuels like LPG and firewood for cooking purposes or serve as a complementary source for electricity and thermal energy production in non-interconnected zones. This could mitigate environmental issues and reduce the prevalence of respiratory diseases associated with the use of firewood

Biogas production from the specialized dairy farming and porcine subsectors in Antioquia, Colombia: theoretical and technical-energy potential approach

Received: February 23rd, 2022 ; Accepted: May 1st, 2022 ; Published: May 11th, 2022 ; Correspondence: [email protected] developing countries, residual biomass usage by means of anaerobic digestion offers several benefits and opportunities, such as a sustainable energy source, production of organic fertilizers and new agrobusiness models. In Latin America, Colombia is one of the most promising markets for the implementation of this technology in terms of availability of biomass and economic growth, as recently reported by local government organizations. In this paper, special attention is given to Antioquia, a department of Colombia with the largest farms of cattle and pigs, according to information reported in 2018 by the Ministry of Agriculture and Rural Development. It is estimated that manure from the porcine subsector in Antioquia has an approximate technical-energy potential of 1,896 TJ year-1 , varying from 1,611 to 2,186 TJ year-1 , corresponding to the 95% confidence interval. In the case of manure generated by the livestock subsector in Antioquia, it is estimated a theoretical energy potential of 8,566 TJ year-1 . However, traditional extensive production systems disseminate manure through the pastures turning centralization of the available residual biomass a difficult task and not senseful. Based on the local practices of the specialized dairy subsector, it is estimated that manure collected during the milking process could reached up to 25% of the total available. Biochemical conversion of this amount of biomass has an estimated technical-energy potential of 187 TJ year-1 , varying from 156 and 236 TJ year-1 , corresponding to the 95% confidence. The aim of this article is to estimate the technical-energy potential for the livestock and porcine subsectors in the Department of Antioquia, based on the available residual biomass according to local farming practices

Methanogens, sulphate and heavy metals: a complex system

Anaerobic digestion (AD) is a well-established technology used for the treatment of wastes and wastewaters with high organic content. During AD organic matter is converted stepwise to methane-containing biogasa renewable energy carrier. Methane production occurs in the last AD step and relies on methanogens, which are rather sensitive to some contaminants commonly found in wastewaters (e.g. heavy metals), or easily outcompeted by other groups of microorganisms (e.g. sulphate reducing bacteria, SRB). This review gives an overview of previous research and pilot-scale studies that shed some light on the effects of sulphate and heavy metals on methanogenesis. Despite the numerous studies on this subject, comparison is not always possible due to differences in the experimental conditions used and parameters explained. An overview of the possible benefits of methanogens and SRB co-habitation is also covered. Small amounts of sulphide produced by SRB can precipitate with metals, neutralising the negative effects of sulphide accumulation and free heavy metals on methanogenesis. Knowledge on how to untangle and balance sulphate reduction and methanogenesis is crucial to take advantage of the potential for the utilisation of biogenic sulphide as a metal detoxification agent with minimal loss in methane production in anaerobic digesters.The research was financially supported by the People Program (Marie Curie Actions) of the European Union's Seventh Framework Programme FP7/2007-2013 under REA agreement 289193

Global patient outcomes after elective surgery: prospective cohort study in 27 low-, middle- and high-income countries.

BACKGROUND: As global initiatives increase patient access to surgical treatments, there remains a need to understand the adverse effects of surgery and define appropriate levels of perioperative care. METHODS: We designed a prospective international 7-day cohort study of outcomes following elective adult inpatient surgery in 27 countries. The primary outcome was in-hospital complications. Secondary outcomes were death following a complication (failure to rescue) and death in hospital. Process measures were admission to critical care immediately after surgery or to treat a complication and duration of hospital stay. A single definition of critical care was used for all countries. RESULTS: A total of 474 hospitals in 19 high-, 7 middle- and 1 low-income country were included in the primary analysis. Data included 44 814 patients with a median hospital stay of 4 (range 2-7) days. A total of 7508 patients (16.8%) developed one or more postoperative complication and 207 died (0.5%). The overall mortality among patients who developed complications was 2.8%. Mortality following complications ranged from 2.4% for pulmonary embolism to 43.9% for cardiac arrest. A total of 4360 (9.7%) patients were admitted to a critical care unit as routine immediately after surgery, of whom 2198 (50.4%) developed a complication, with 105 (2.4%) deaths. A total of 1233 patients (16.4%) were admitted to a critical care unit to treat complications, with 119 (9.7%) deaths. Despite lower baseline risk, outcomes were similar in low- and middle-income compared with high-income countries. CONCLUSIONS: Poor patient outcomes are common after inpatient surgery. Global initiatives to increase access to surgical treatments should also address the need for safe perioperative care. STUDY REGISTRATION: ISRCTN5181700

Influence of chemical composition on the biochemical methane potential of agro-industrial substrates from Estonia

Batch trials were carried out to evaluate the Biochemical Methane Potential (BMP) of 61 different substrates collected from agricultural farms and industrial sites in Estonia. Tests were performed in 500 mL plasma bottles at 36°C. The highest methane yield from all tested substrates was obtained from unconsumed dairy products (557 ± 101 L kg-1 VS) while the lowest was obtained from animal slurries (238 L kg-1 VS ± 42). From tested energy crops, foxtail millet achieved the highest methane yield (320 L kg-1 VS). Silages from different crops presented methane yields from 296 ± 31 L CH4 kg-1 VS to 319 ± 19 L CH4 kg-1 VS. The influence of chemical composition and kinetic rate constants (k) on methane potential was analyzed. Anaerobic digestibility of selected agro-industrial substrates was markedly influenced by their organic content, i.e. total proteins and lignin concentrations. Rate constants were found to correlate negatively with hemicellulose, cellulose and lignin (p < 0.05). Results from this study suggest that an appropriate characterization of the chemical composition of the substrates is important not only for predicting BMP and the kinetics rates, but also for identifying possible inhibitors during the anaerobic digestion process. Results on the BMP and national availability of studied substrates indicate that herbal biomass and agro-industrial residues are promising substrates for biogas production in agricultural biogas facilities in Estonia. © 2017, Eesti Pollumajandusulikool. All rights reserved

Use of failure-to-rescue to identify international variation in postoperative care in low-, middle- and high-income countries: A 7-day cohort study of elective surgery

The incidence and impact of postoperative complications are poorly described. Failure-to-rescue, the rate of death following complications, is an important quality measure for perioperative care but has not been investigated across multiple health care systems. Methods. We analysed data collected during the International Surgical Outcomes Study, an international 7-day cohort study of adults undergoing elective inpatient surgery. Hospitals were ranked by quintiles according to surgical procedural volume (Q1 lowest to Q5 highest). For each quintile we assessed in-hospital complications rates, mortality, and failure-to-rescue. We repeated this analysis ranking hospitals by risk-adjusted complication rates (Q1 lowest to Q5 highest). Results. A total of 44 814 patients from 474 hospitals in 27 low-, middle-, and high-income countries were available for analysis. Of these, 7508 (17%) developed one or more postoperative complication, with 207 deaths in hospital (0.5%), giving an overall failure-to-rescue rate of 2.8%. When hospitals were ranked in quintiles by procedural volume, we identified a threefold variation in mortality (Q1: 0.6% vs Q5: 0.2%) and a two-fold variation in failure-to-rescue (Q1: 3.6% vs Q5: 1.7%). Ranking hospitals in quintiles by risk-adjusted complication rate further confirmed the presence of important variations in failureto- rescue, indicating differences between hospitals in the risk of death among patients after they develop complications. Conclusions. Comparison of failure-to-rescue rates across health care systems suggests the presence of preventable postoperative deaths. Using such metrics, developing nations could benefit from a data-driven approach to quality improvement, which has proved effective in high-income countries

Kuluttajabarometri maakunnittain 2000, 2. neljännes

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