Insights into hydrothermal treatment of biomass blends: Assessing energy yield and ash content for biofuel enhancement.

This study explores the Hydrothermal Carbonization (HTC) treatment of lignocellulosic biomass blends, delving into the influence of several key parameters: temperature, additive nature and dosage, residence time, and biomass composition. Rapeseeds, Pinus radiata sawdust, oat husks, and pressed olive served as the studied biomasses. One hundred twenty-eight experiments were conducted to assess the effects on mass yield (MY), energy yield (EY), higher heating value (HHV), and final ash content (ASH) by a Factorial Experimental Design. The derived model equations demonstrated a robust fit to the experimental data, averaging an R2 exceeding 0.94, affirming their predictive accuracy. The observed energy yield ranged between 65% and 80%, notably with sawdust and olive blends securing EY levels surpassing 70%, while rapeseed blends exhibited the highest HHV at 25 MJ/kg. Temperature emerged as the most influential factor, resulting in an 11% decrease in MY and a substantial 2.20 MJ/kg increase in HHV. Contrastingly, blend composition and additive presence significantly impacted ASH and EY, with all blends exhibiting increased ASH in the presence of additives. Higher initial hemicellulose and aqueous extractive content in raw biomass correlated proportionally with heightened HHV.

Effect of Adding Bovine Skin Gelatin Hydrolysates on Antioxidant Properties, Texture, and Color in Chicken Meat Processing.

(1) Background: Phosphates are used in the food industry to improve water retention and product quality. However, when consumed in excess, they can be harmful to health. Instead, bovine skin gelatin hydrolysates present health benefits such as being a rejuvenating agent, stimulating collagen production, and improving food quality, in addition to being a source of protein. The effect of the addition of bovine skin gelatin hydrolysates on the texture and color of thermally processed chicken meat (boiled type) and antioxidant activity was evaluated. (2) Methods: Hydrolysates were prepared with subtilisin with the degree of hydrolysis being 6.57 and 13.14%, which were obtained from our previous study. (3) Results: The hydrolysates improved the firmness of the meat matrix compared to the control. Additionally, the hydrolysate with a 13.14% degree of hydrolysis reached the same firmness (p > 0.05) as the commercial ingredient sodium tripolyphosphate at its maximum limit allowed in the food industry when it was applied at 5% (w/w meat) in the meat matrix, improving firmness over the control by 63%. Furthermore, both hydrolysates reached a similar color difference to sodium tripolyphosphate at its maximum allowed limit when applied at a concentration of 2% (w/w meat). Additionally, it was found that these hydrolysates obtained the same antioxidant activity as sodium tripolyphosphate, capturing free radicals at 10%. (4) Conclusion: The findings of this study suggest that bovine skin gelatin hydrolysates can be applied as an ingredient with functional properties, being an alternative to phosphates to improve the quality of meat products.

Hybrid porous media gasification of urban solid waste pre-treated by hydrothermal carbonization.

Global population growth and rising consumption levels have significantly increased resource use and energy demand, leading to higher greenhouse gas concentrations and increased waste output. As a result, alternative waste treatment methods for sustainable municipal solid waste (MSW) management are crucial. This research evaluates the efficiency of integrating hydrothermal carbonization (HTC) and gasification for an optimized MSW biomass blend. HTC was conducted for one hour at 220°C in a 5 L reactor, followed by gasification in a hybrid porous medium gasifier. The study investigated the effects of different filtration speeds on combustion temperature and hydrogen concentrations. The results showed that a filtration speed of 35 cm/s resulted in a maximum combustion temperature of 1035.7°C. The temperature remained consistent across filter speeds, while higher velocities yielded higher hydrogen concentrations. Additionally, increasing the filtration velocity raised temperatures in the hybrid bed while increasing the volumetric fraction of biomass decreased maximum temperatures. This research contributes to the understanding of merging HTC and gasification for MSW biomass blend treatment, aiming to reduce environmental impacts and costs while promoting renewable resources for long-term energy production.

An environmental assessment for municipal organic waste and sludge treated by hydrothermal carbonization.

Climate change is the world's greatest challenge today, the reason why it is urgent to optimize industrial processes and find new renewable energy sources. Hydrothermal carbonization (HTC) is one of the Waste-to-Energy technologies with greater projections due to its operative advantages. However, for its large-scale implementation, there are challenges related to the variability of the composition of the waste biomass and the seasonal and geographical availability. This research applied the Life Cycle Analysis methodology to evaluate the environmental impacts caused by three biomasses blends as raw material in the HTC process at laboratory scale. The blends analyzed considered different organic fractions of municipal solid waste (food and pruning) and sewage sludge. The results showed that blend 1 had a lower environmental impact for the case of production in the experimental laboratory level, compared with blends 2 and 3. This is mainly due to its greater calorific value and mass yield, which allows obtaining more hydrochar compared with the other blends, increasing the energy efficiency of the process. Also, between 87.94% and 98.00% of the energy reduction is required to obtain neutral impacts regarding the energy requirements in the experimental laboratory level scenario and the Chilean energy matrix. The processing of blends in HTC has excellent potential in a context where municipal solid wastes have been disposed in sanitary landfills or dumps, as in most emerging countries. Since this study incorporated data from the literature, future studies should perform an elemental analysis to provide experimental and differentiated data.

Processing methodology of global anthropogenic emissions for air quality modeling.

The Global Emissions Initiative (GEIA) stores and offers global datasets of emission inventories developed in the last 30 years. One of the most recently updated global datasets covering anthropogenic source emissions is the Copernicus Atmosphere Monitoring Service (CAMS). This study applied NetCDF Command Operator (NCO) software to preprocess the anthropogenic sources included in the CAMS datasets and converted those files as an input in the Sparse Matrix Operator Kerner Emissions (SMOKE) model for future air quality modeling. As a result, six steps were applied to obtain the required file format. The case of the central coast in Chile was analyzed to compare the global database and official reports for the on-road transport sector. As a result, some differences were shown in the most populated locations of the domain of analysis. The rest of the zones registered similar values. The methodology exposed in this report could be applied in any other region of the planet for air quality modeling studies. The development of global datasets such as CAMS is useful for hemispheric analysis and could bring an estimation on the mesoscale. It represents an opportunity for those locations without official reports of non-updated data.•This study applied NCO commands available for the preprocessing of the CAMS dataset files.•The emissions and temporal profile registered in CAMS datasets must be compared to official reports of transport sectors.•The development of global datasets such as CAMS is useful for hemispheric analysis and could bring an estimation on the mesoscale.

The black carbon dispersion in the Southern Hemisphere and its transport and fate to Antarctica, an Anthropocene evidence for climate change policies.

Black carbon (BC) has been measured in Antarctica's air, and its global warming effect can potentially speed up the ice melting in the most solid water reservoir of the planet. However, the primary responsible sources are not well evidenced in this region. The dispersion of black carbon emissions from the Southern Hemisphere was conducting using atmospheric chemical transport model and we compared the results with satellite registries from March 1st to April 30th in 2014. The emission inventory considered the anthropogenic and biomass burning emissions from global datasets. The largest and most populated cities in Southern Hemisphere showed the higher emission of BC. As a result, the average daily concentrations of atmospheric BC were around 4 ng/m3 in most regions of Antarctica according to its pristine characteristics. We analyzed fifteen relevant sites in coastal zones of Antartica and some peaks registered by the satellite records were not replicated by model outputs and it was mainly associated with the lack of emissions. Finally, we made simulations in the same period without biomass burning emissions and we observed decreased concentrations of BC in the range of 20-50%. As a result, we show that the black carbon transportation from the continental land to the polar region took place in 17-24 days during the Austral summer and the biomass burning emissions were the primary source. Black Carbon deposition in Antarctica is not permanent, but the uncontrolled emissions from Southern Hemisphere can increase its transportation to the white continent and make its accumulation during the period when the weak polar vortex occurs.

Black and organic carbon fractions in fine particulate matter by sectors in the South Hemisphere emissions for decision-making on climate change and health effects.

Some databases report global emissions of certain pollutants. Emissions Database for Global Atmospheric Research (EDGAR) project is one of these, which also records emissions by sources. In this study, the emissions of black and organic carbon and fine particulate matter from the EDGAR database were used as an input to process it in the Sparse Matrix Operator Kernel Emissions (SMOKE) model. We showed the spatial distribution of the fraction of black and organic carbon in particulate matter from each source in the Southern Hemisphere. Also, we extracted these ratios for several cities in the domain of analysis. The results and methodology of this study could improve the emission inventories with bottom-up methodology in areas without information located at Southern Hemisphere. Also, it could be relevant to obtain better performance in air quality modeling at the local level for decision-making on climate change and health effects.

Sensitivity analysis of biodiesel blends on Benzo[a]pyrene and main emissions using MOVES: A case study in Temuco, Chile.

Temuco is one of the most highly wood-smoke polluted cities in Chile; however, the diesel mobile sources are growing very fast in the past 10 years and so far very few studies have been done. The main goal of this research was to develop a 2013 emission inventory of criteria pollutants and Benzo[a]pyrene (BaP) and to evaluate the use of six biodiesel blends of 0%, 1%, 4%, 8%, 12%, and 20% by volume of fuel in diesel motors from the vehicle fleet within the mentioned areas using the Motor Vehicle Emission Simulator (MOVES). Input parameters for the base year 2005 were estimated to implement and adapt the model in Chile, while results of NOx, PM10, PM2.5, NH3, CO2 equivalent and SO2 were compared with the Chilean Emission Inventory estimated by the model "Methodology for the Calculation of Vehicle Emissions." The 2013 emissions reduced with respect to 2005, in the majority of the contaminants analyzed, despite the 47% increase in the annual miles traveled. Using biodiesel blends, an emission reduction was estimated at up to 15% in particulate matter, BaP, and CO for the year 2013, as well as an increment of 2% in NOx emissions, attributed to low sulfur content (50 ppm) in the diesel and the antiquity of the vehicle fleet. The results obtained gave evidence of the influence of the biodiesel use in the pollutant emissions to improve the Chilean air quality, as well as providing a strategy for this air quality management.