Digestate

Traducción y adaptación del Capítulo 8 del libro "THE BIOGAS HANDBOOK, SCIENCE, PRODUCTION AND APPLICATIONS”, Editado por A. Welinger, J. Murphy & D. Baxter, publicado en el año 2013.Este documento se publica como documento divulgativo de la empresa CCA Biogás, en su página de Facebook, con fecha 32 de mayo de 2019.

Se propone generar la electricidad a partir del biogás que se produce mediante la digestión anaerobia del estiércol que se genera en el feedlot. Se considera una población instantánea en el feedlot de 2,000 reses y se programa la generación de electricidad de manera complementaria a los paneles solares existentes en la finca.

This work aims to investigate the applicability of electrical resistivity tomography (ERT) as a non-destructive tool of agricultural soil characterization after digestate of fruit and vegetable (DFV) amendment application. DFV was applied at 30 t ha −1 in one application (D1), split into 2 (D2) and 6 applications (D6), and compared with initial state (IS) on field plots of 10 m 2. The high-resolution 2D ERT prospecting was performed using a ABEM SAS4000 multi-electrode Lund imaging survey system with a set of 16 electrodes evenly spaced 0.1 m. The resistivity values with ERT profiles using the Wenner array range globally from 0 to 200 Ω m. All treatments proposed decreased soil resistivity to 0-30 cm depth profile. Splitting digestate shows more intensive decreasing resistivity in the top layer and less in the bottom, and moves the iso-resistivity lines lower than 30 Ω m from 7 cm depth to 12, 20, and 30 cm depth, respectively, for D6, D2, and D1. The resistivity folding at 15 to 30 cm depth was 87, 80, and 67% then 58, 42, and 37%, respectively, for D1, D2, and D6. The low resistivity values may be due to soil organic matter flow illustrated. Digestate applied once acted on the soil with heterogeneous way along the profile. Splitting it increases the thickness of foam layer homogeneously. ERT seems a promising technique for the survey of soil organic matter content monitoring, dispersion, and assessment.

The solid fraction obtained by mechanical separation of digestate from anaerobic digestion plants is an attractive feedstock for the pyrolysis process. Especially in the case of digestate obtained from biogas plants fed with energy crops, this can be considered a lignin rich residue. The aim of this study is to investigate the pyrolytic kinetic characteristics of solid digestate. The Starink model-free method has been used for the kinetic analysis of the pyrolysis process. The average Activation Energy value is about 204.1 kJ/mol, with a standard deviation of 25 kJ/mol, which corresponds to the 12% of the average value. The activation energy decreased along with the conversion degree. The variation range of the activation energy is about 99 kJ/mol, this means that the average value cannot be used to statistically represent the whole reaction. The Master-plots method was used for the determination of the kinetic model, obtaining that n-order was the most probable one. On the other hand, the process cannot be modeled with a single-step reaction. For this reason it has been used an independent parallel reactions scheme to model the complete process.

Traducido y adaptado del Capítulo 8 del libro “THE BIOGAS HANDBOOK, SCIENCE, PRODUCTION AND APPLICATIONS”, , editado por ARTHUR WELLINGER, JERRY MURPHY & DAVID BAXTER, publicado en el año 2013. La parte inicial del capítulo se publicó en las partes I y !!. Con esta parte III se completa la traducción y adaptación de ese capitulo.

Conferencia presentada en el Foro Taller CYTED Energías Renovables, grandes oportunidades, llevado a cabo en Arequipa, Perú, del 27 al 30 de noviembre de 2018, en la cual se hace una introducción al biogás como combustible gaseoso, producto del procesamiento de la biomasa por medio de la biotecnología anaerobia, se explican los antecedentes y situación actual de la empresa CCA Biogás y se detallan los principales proyectos de biogás desarrollados por la empresa, para su uso como biofertilizante.como combustible para sustituir combustibles fósiles como el Gas Licuado del Petróleo y para producir electricidad, incluyendo el desarrollo de los procesos de eliminación de los compuestos de azufre del biogás,.

Anaerobic digestion is often applied for biological conversion and valorization of organic waste, waste water and other biomass sources as renewable energy and biofuel in the form of biomethane. Composition of the material remaining after digestion, or digestate, is highly dependent on processed feedstocks. This by-product is usually rich in nutrients such as nitrogen and phosphorus, so it is potentially reusable as fertilizer or nutritive broth in agricultural systems. Alternatively, the digestate may need post-treatment based on nutrient removal or recovery strategies. The use of life-cycle assessment tools is becoming popular to analyze nutrient handling scenarios. This study reviews, through a bibliometric-based approach, the research outputs and global trends in the area of knowledge of nutrient management from digestates in the last 30 years, 2017 included. Documentary production followed an upward trend, with a relative productivity in the last 3 years greater than 37% of the total number of appeared publications. China, USA and Spain were the three most prolific countries. The particular interest in nutrient management alternatives and its evolution were identified. Trends for promoting sustainability include low environmental impact, holistic agro-energy solutions, reduced consumption of resources during digestate processing, and circular economy scenarios based on concepts such as (bio)refinery and recovery of valuable and marketable products.

Se presenta el Estudio de Factibilidad del Proyecto Biogás Santa Martha para Generación de Electricidad en el feedlot de la Finca Santa Martha de la Empresa Castillo Poultry LLC, en el Municipio La Paz Centro, con el objetivo de lograr la reducción de más del 50% del consumo de energía eléctrica del engorde de pollos, a partir de la electricidad que se genera con el biogás que se obtiene de la digestión anaerobia del estiércol del feedlot. Se considera una población instantánea de 2,000 reses en el feedlot y se programa la generación de electricidad en el horario alterno al horario en que funcionan los paneles solares.

Solid digestate (SD) represents an environmental problem due to the continuous increase of biogas production. In the present study four white-rot fungal strains were screened for their ability to grow on two different SD samples, obtained from industrial biogas plants, using wheat straw (WS) as a control medium. Results show that i) the feedstock used in the biogas plant influences the time required for the colonization of the corresponding SD and ii) different fungal strains have different capabilities to colonize the same digestate. In particular, Pleurotus ostreatus SMR 684 reached the maximum proliferation on corn silage digestate (CSD) in the shortest time (12 days). Subsequently, P. ostreatus was grown on WS and CSD for 42 days with measurement of lignocellulolytic activities and lignocellulose components (lignin, cellulose and hemicellulose). Enzymatic activities reached a maximum around the 24 th day of incubation. Ligninolytic activities showed similar trends on CSD and on ...

Anaerobic digestion has emerged as the preferred treatment for organic fraction of municipal solid waste. Digestate management strategies are devised not only for safe disposal but also to increase the value and marketability. Regulations and standards for digestate management are framed to address the pollution concerns, conserve vulnerable zones, prevent communicable diseases, and to educate on digestate storage and applications. Regulations and the desired end uses are the main drivers for the enhancement of digestate through pretreatment, in vessel cleaning, and post-digestion treatment technologies for solid and liquid fractions of digestate. The current management practice involves utilization of digestate for land application either as fertilizer or soil improver. Prospects are bright for alternative usage such as microalgal cultivation, biofuel and bioethanol production. Presently, the focus of optimization of the anaerobic digestion process is directed only towards enhancin...

Se presenta el Estudio de Factibilidad del Proyecto Biogás Santa Martha para Generación de Electricidad en el feedlot de la Finca Santa Martha de la Empresa Castillo Poultry LLC, en el Municipio La Paz Centro, con el objetivo de lograr la reducción de más del 50% del consumo de energía eléctrica del engorde de pollos, a partir de la electricidad que se genera con el biogás que se obtiene de la digestión anaerobia del estiércol del feedlot. Se considera una población instantánea de 2,000 reses en el feedlot y se programa la generación de electricidad en el horario alterno al horario en que funcionan los paneles solares.

The performance of an anoxic-aerobic microalgal-bacterial system treating synthetic food waste digestate at 10 days of hydraulic retention time via nitrification-denitrification under increasing digestate concentrations of 25%, 50%, and 100% (v/v) was assessed during Stages I, II and III, respectively. The system supported adequate treatment without external CO2 supplementation since sufficient inorganic carbon in the digestate was available for autotrophic growth. High steady-state Total Organic Carbon (TOC) and Total Nitrogen (TN) removal efficiencies of 85–96% and 73–84% were achieved in Stages I and II. Similarly, PO43−-P removals of 81 ± 15% and 58 ± 4% were recorded during these stages. During Stage III, the average influent concentrations of 815 ± 35 mg TOC·L−1, 610 ± 23 mg TN·L−1, and 46 ± 11 mg PO43−-P·L−1 induced O2 limiting conditions, resulting in TOC, TN and PO43−-P removals of 85 ± 3%, 73 ± 3%, and 28 ± 16%, respectively. Digestate concentrations of 25% and 50% favored nitrification-denitrification mechanisms, whereas the treatment of undiluted digestate resulted in higher ammonia volatilization and hampered nitrification-denitrification. In Stages I and II, the microalgal community was dominated by Chlorella vulgaris and Cryptomonas sp., whereas Pseudoanabaena sp. was more abundant during Stage III. Illumina sequencing revealed the presence of carbon and nitrogen transforming bacteria, with dominances of the genera Gemmata, Azospirillum, and Psychrobacter during Stage I, II, and III, respectively. Finally, the high settleability of the biomass (98% of suspended solids removal in the settler) and average C (42%), N (7%), P (0.2%), and S (0.4%) contents recovered in the biomass confirmed its potential for agricultural applications, contributing to a closed-cycle management of food waste.

In recent years, sewage sludge (SS) and bio-waste management have attracted increasing environmental attention. In this study, hydrothermal carbonization (HTC) technology is investigated in the framework of a co-treatment of sewage sludge digestate (SSD) and an organic fraction of municipal solid waste (OW). The proposed configuration integrates HTC with anaerobic digestion (AD) in an inter-stage configuration (AD1 + HTC + AD2). The effects of different percentages of OW added to SSD in the HTC treatment are evaluated in terms of characteristics and methane yield of the produced HTC liquor (HTCL) and HTC slurry (i.e., the mixture hydrochar-HTCL), as well as dewaterability of the HTC slurry. Results show that, with the increase in the percentage of OW in the OW-SSD mixture fed to the HTC process, production of biogas and biomethane of both HTC slurry and HTCL increases. The highest biogas production is achieved when a mixture consisting of half SSD and half OW is used, reaching 160 ±...

Traducido y adaptado del Capítulo 8 del libro “THE BIOGAS HANDBOOK, SCIENCE, PRODUCTION AND APPLICATIONS”, , editado por ARTHUR WELLINGER, JERRY MURPHY & DAVID BAXTER, publicado en el año 2013. La parte inicial del capítulo se publicó en las partes I y !!. Con esta parte III se completa la traducción y adaptación de ese capitulo.

Solid digestate (SD) represents an environmental problem due to the continuous increase of biogas production. In the present study four white-rot fungal strains were screened for their ability to grow on two different SD samples, obtained from industrial biogas plants, using wheat straw (WS) as a control medium. Results show that i) the feedstock used in the biogas plant influences the time required for the colonization of the corresponding SD and ii) different fungal strains have different capabilities to colonize the same digestate. In particular, Pleurotus ostreatus SMR 684 reached the maximum proliferation on corn silage digestate (CSD) in the shortest time (12 days). Subsequently, P. ostreatus was grown on WS and CSD for 42 days with measurement of lignocellulolytic activities and lignocellulose components (lignin, cellulose and hemicellulose). Enzymatic activities reached a maximum around the 24th day of incubation. Ligninolytic activities showed similar trends on CSD and on W...

Solid food waste digestate MDF dust Sodium silicate Adsorption Isotherms and kinetics ABSTRACT Anaerobic digestate originating from food waste has been studied herein for two different purposes. Firstly, for combustion, co-granulation of the digestate and medium density fibreboard (MDF) dust with the addition of sodium silicate as the binder was used to produce the granular solid biofuel. It was found that increasing the content of the medium density fibreboard dust could increase the calorific value but had no significant effect on the strength of the final granules. Additionally, a significant reduction of the ash content was also observed. For heavy metal removal, granules made using the digestate and sodium silicate binder were carbonised to produce biochar which was characterised and applied as adsorbent materials. The biochar has a good removal capacity for both lead and cadmium, and the binder concentration had a positive correlation with the removal capacity of the resultant biochar. The maximum lead removal capacity (355.3 mg g −1) of biochar made using 3 wt.% sodium silicate binder, was six times more than the analogous commercial activated carbon. Langmuir model showed better fitting for adsorption data of Pb 2+ , while the Freundlich model showed better fitting of Cd 2+. For both Pb 2+ and Cd 2+ kinetic data, the pseudo-second-order had a better correlation. Our approach helps aid and facilitate the concept of the circular economy by effectively up-cycling and valorising waste lignocellulosic biomass such as food waste digestate into value-added products.

Presentación realizada en el Taller Ambiental "Importancia de la Aplicación de los Biodigestores como Técnica Sostenible en el Medio Ambiente”, que organizaron de conjunto el Consejo Nacional de Ciencia y Tecnología (CONICYT) y el Ministerio de Medio Ambiente y Recursos Naturales (MARENA), en el Auditorio Andrés Castro, del CONICYT, el viernes 11 de diciembre de 2020. En la presentación se hace primero una breve introducción sobre el origen y fundamentos de la digestión anaerobio y después se presentan las experiencias de distintos proyectos de desarrollo de biogás en Nicaragua desde 1982 hasta la fecha y se abunda en los proyectos realizados por la empresa CCA Biogás. Además, se presenta la tecnología de digestión anaerobia que oferta la empresa a partir del 2020 y termina con las conclusiones y recomendaciones sobre el desarrollo del biogás en Nicaragua.

Conferencia presentada en el Foro Taller CYTED Energías Renovables, grandes oportunidades, llevado a cabo en Arequipa, Perú, del 27 al 30 de noviembre de 2018, en la cual se hace una introducción al biogás como combustible gaseoso, producto del procesamiento de la biomasa por medio de la biotecnología anaerobia, se explican los antecedentes y situación actual de la empresa CCA Biogás y se detallan los principales proyectos de biogás desarrollados por la empresa, para su uso como biofertilizante.como combustible para sustituir combustibles fósiles como el Gas Licuado del Petróleo y para producir electricidad, incluyendo el desarrollo de los procesos de eliminación de los compuestos de azufre del biogás,.

As an alternative to applying the hydrothermal treatment to the raw algal feedstock before the anaerobic digestion (i.e. pre-treatment), one considered a post-treatment scenario where anaerobic digestion is directly used as the primary treatment while the hydrothermal treatment is thereafter applied to the digestate. Hydrothermal treatments such as wet oxidation (WetOx) and hydrothermal carbonization (HTC) were compared at a temperature of 200°C, for initial pressure of 0.1 and 0.82MPa, and no holding time after the process had reached the temperature setpoint. Both WetOx and HTC resulted in a substantial solids conversion (47-62% with HTC, 64-83% with WetOx, both at 0.82MPa) into soluble products, while some total chemical oxygen demand-based carbon loss from the solid-liquid phases was observed (20-39%). This generated high soluble products concentrations (from 6.2 to 10.9g soluble chemical oxygen demand/L). Biomethane potential tests showed that these hydrothermal treatments allo...

The present study investigated the acidification treatment of an agrowaste digestate and a food waste digestate, which is necessary before the addition of the wood ashes to attain the pH of zero point of charge in the blend intended to behave as a slow-release fertilizer. The 336-h acidification treatments of the 2.39 ± 0.35 g of digestates were performed with high and low doses of four commercial acids (sulfuric, hydrochloric, nitric, and lactic acids) in 50-mL capped Corning® tubes. For analytical purposes, after the incubation, ultrapure milli-Q® water was added at a rate of 10 mL for each gram of digestate to create a water-soluble phase that allowed the measurement of the pH and the electric conductivity. The results showed that the optimum dose and type of acid were very dependent on the nature of the anaerobic digestate. The maximum buffer capacity of the agrowaste digestate was 0.07 mmol H+-H2SO4/g, but this increased by adding the food waste digestate with a greater content...

A large volume of food is being wasted every year, while the pulp and paper industry also generate a large amount of solid wastes on a daily basis, causing environmental challenges around the world. Dry anaerobic digestion (AD) of these solid wastes is a cost-effective method for proper management. However, dry digestion of these waste streams has been restricted due to their complex structure, the presence of possible inhibitors and inappropriate operating conditions. In light of this fact, dry digestion of food waste (FW) and paper wastes (PW) was conducted at different total solid (TS) concentrations of reactor mixtures of 14%, 16%, 18% and 20% TS, corresponding to substrate to inoculum (S/I) ratio of 0.5 and 1; investigating the optimum operating conditions for effective dry digestion of these complex wastes. The highest methane yields of 402 NmlCH4/gVS and 229 NmlCH4/gVS were obtained from digestion of FW and PW, respectively at 14%TS corresponding to an S/I ratio of 0.5. Incre...

This study aimed to determine the suitability of sugar beet pulp digestion by-products as soil amendments for maize grown for energy purposes. In a plot experiment, nitrogen fertilizer at a standard rate of 200 kg N ha−1 was applied as a control vs. treatment with solid and liquid digestate fractions. Digestate was obtained from a gasifier processing only sugar beet pulp. Following harvest, heating and calorific values were determined together with the yield and chemical composition of the maize cob and stover. It was found that soil amendment with crude (unseparated) digestate or its two fractions (separated into liquid and solid) produced higher yields of maize cobs and stover compared with the application of standard fertilizer. An analysis of the energy value of the maize plant revealed differences between the studied soil treatments. Cobs obtained from plots treated with the digestate showed higher calorific and heating values than those obtained from control plots; however, ma...

""The variables influencing corrosion of three metals (galvanised steel, stainless steel, brass) usable for a manure nutrient probe were examined, identifying the best material for field applications. The nutrients in 18 liquid manures were then estimated through the voltage drop between the terminals of a prototype probe.

Response Surface Modelling gave the regression functions relating each investigated response only to the statistically-significant factors.

After 168 h in the manure, it was determined that: stainless steel was the most suitable material for very close electrodes (mass: −1.8% at 15 mm), brass can be used with any inter-electrode distance (mass: −13.0% maximum at 35 mm).

The prototype probe gave reliable estimates (R2 ⩾ 0.744) of Ntot, Namm, Ptot, Ktot when dry matter and temperature were also accounted for in the regression analysis. Not considering dry matter but just electronically-detectable quantities (temperature, voltage drop), the estimates were only reliable (R2 ⩾ 0.656) above 20 °C.""