A simple mass balance tool to predict carbon and nitrogen fluxes in anaerobic digestion systems

Agricultural activities can have several adverse impacts on the environment; such as important greenhouse gas (GHG) emissions. To implement effective mitigation measures and create effective policies, it is necessary to know the full carbon and nitrogen budgets of agro-ecosystems. However, very often, information regarding the pools or fluxes involved in the carbon and nitrogen cycles is limited, and essential complementary data needed for a proper interpretation is lacking.This study aimed to quantify all the relevant pools and fluxes of a winter rapeseed, a widely spread crop in the Europe and Baltic regions. The N2O and CH4 fluxes were measured weekly using the closed static chamber method from August 2016 to August 2017 in a winter rapeseed field in Central Estonia. Additionally, nutrient leaching and soil chemical parameters, as well as environmental parameters like soil moisture, electrical conductivity and temperature were monitored. At the end of the season, the rapeseed and weed biomasses were collected, weighed and analyzed. The remaining relevant fluxes in the N cycle were calculated using various non-empirical methods: NH3 volatilization was estimated from slurry and environmental parameters, N deposition and NOx emissions were obtained from national reports, and N2 emissions were calculated with the mass balance method. Regarding the C cycle, gross primary production (GPP) of the rapeseed field was also calculated by the mass balance method. Simultaneously, for comparison and validation purposes, GPP was estimated from the data provided by MOD17A2H v006 series from NASA, and N2 was estimated from the measured emissions of N2O using the N2:N2O ratio calculated from the DAYCENT model equations.N2 emissions and GPP were the biggest fluxes in the N and C cycles, respectively. N2 emissions were followed by N extracted with plant biomass in the N cycle, while in the carbon cycle soil and plant respiration and NPP were the highest fluxes after GPP. The carbon balance was positive at the soil level, with a net increase in soil carbon during the period, mainly due to GPP carbon capture. Contrarily, the nitrogen balance resulted in a net loss of N due to the losses related to gaseous emissions (N2 and N2O) and leaching.To conclude, it was possible to close the C and N budgets, despite the inherent difficulties of estimating the different C and N environmental pools and fluxes, and the uncertainties deriving from some of the fluxes estimations.

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Estimation of methane generation based on anaerobic digestion and mass balance at Kiteezi Landfill, Kampala, Uganda

African Journal of Environmental Science and Technology ◽

10.5897/ajest2015.1922 ◽

2015 ◽

Vol 9 (9) ◽

pp. 741-746 ◽

Cited By ~ 4

Author(s):

Mboowa Drake ◽

Banadda Noble ◽

Kiggundu Nicholas ◽

Kabenge Isa ◽

John Komakech Allan

Keyword(s):

Anaerobic Digestion ◽

Mass Balance ◽

Methane Generation

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EFFECT OF FOUR DIFFERENT PRETREATMENTS IN NITROGEN AND PHOSPHORUS FLOW AND MASS BALANCE IN EFFLUENTS OF A RECIRCULATING AQUACULTURE SYSTEM

CICIMAR Oceánides ◽

10.37543/oceanides.v31i2.183 ◽

2016 ◽

Vol 31 (2) ◽

pp. 21

Author(s):

Juan P. González -Hermoso ◽

Emilio Peña -Messina ◽

Anselmo Miranda -Baeza ◽

Luis R. Martínez -Córdoba ◽

María T. Gutiérrez -Wing ◽

...

Keyword(s):

Anaerobic Digestion ◽

Mass Balance ◽

Biological Degradation ◽

Nitrogen And Phosphorus ◽

Recirculating Aquaculture ◽

P Content ◽

Recirculating Aquaculture Systems ◽

High Concentrations ◽

Intensive Aquaculture ◽

Phosphorus Flow

ABSTRACT. The effluents from intensive aquaculture operations such as recirculating aquaculture systems (RAS) have high concentrations of sludge that can become a source of pollution if they are not properly treated and disposed. Anaerobic digestion is commonly used for biological degradation of sludge. Pretreatments prior to anaerobic digestion can enhance sludge degradation and decrease nitrogen and phosphorus load through microbial activity. This study examines the effect of four different pretreatments (biological, chemical, mechanical and thermal) in the N and P fluxes and mass balance from a RAS effluent in a seven-month period at ambient temperature. Each month a 15-day experiment was performed. All pretreatments, except chemical, removed N (thermal 29.78%, biological 36.75%, control 42.25%, mechanical 49.46%, chemical -7.68%). All pretreatments produced phosphorus (chemical 1.96%, mechanical 16.07%, thermal 24.37%, biological 32.39%, control 58.50%). Our results showed that the mechanical pretreatment was the most effective in removing N. In contrast, none of the pretreatments reduced P content in the sludge.Efecto de cuatro pretratamientos en el flujo y balance del nitrógeno y el fósforo en efluentes de un sistema de recirculación acuícolaRESUMEN. Los efluentes de un tipo de cultivo intensivo como los Sistemas de Recirculación Acuícola (SRA) presentan altas concentraciones de lodos que pueden llegar a ser una fuente de contaminación si no son tratados y dispuestos apropiadamente. La digestión anaeróbica es usualmente empleada para llevar a cabo la degradación de los lodos. Los pretratamientos previos a la digestión anaeróbica pueden mejorar la degradación de los lodos, así como reducir la carga de nitrógeno y fósforo a través de la actividad microbiana. Este estudio examinó el efecto de cuatro pretratamientos (biológico, químico, mecánico y térmico) en el flujo y balance de masas de N y P de efluentes de un SRA durante un periodo de 7 meses a temperatura ambiente. En cada mes se llevó a cabo un experimento de 15 días. Todos los pretratamientos a excepción del químico, eliminaron nitrógeno (térmico 29.78%, biológico 36.75%, control 42.25%, mecánico 49.46%, químico -7.68%). Todos los pretratamientos produjeron fósforo (químico 1.96%, mecánico 16.07%, térmico 24.37%, biológico 32.39%, control 58.60%). Nuestros resultados indican que el pretratamiento mecánico fue el más efectivo para eliminar N. En contraste, ninguno de los pretratamientos redujo la concentración de fósforo.

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Testing the Impact of Waste from Anaerobic Digestion (Enriched with an Organic Component) on the Quality of Agricultural Land

GeoScience Engineering ◽

10.1515/gse-2017-0020 ◽

2017 ◽

Vol 63 (4) ◽

pp. 33-38

Author(s):

Jana Kodymová ◽

Miroslav Kyncl ◽

Hana Švehláková ◽

Magdaléna Bártková

Keyword(s):

Anaerobic Digestion ◽

Field Trial ◽

Laboratory Tests ◽

Agricultural Land ◽

Mineral Fertilizer ◽

Organic Component ◽

Carbon And Nitrogen ◽

Macro And Micronutrients ◽

The Impact

Abstract Waste from anaerobic digestion is considered as a mineral fertilizer and it is usually applied to agricultural land. The aim of our attempt was to enrich this waste from anaerobic digestion (digestate) with an organic component (in our case represented by haylage). For this purpose, we made different mixtures of digestate and haylage in different weight ratios. In the field trial, the effect of these mixtures on the soil, under standard agricultural conditions, was monitored. Selected accessible nutrients (P, K, Mg, Mn, Ca) and the amount of carbon and nitrogen in the soil were monitored. The results of the laboratory tests confirmed that the areas where the sowing and digestate mixtures were applied showed greater amounts of macro- and micronutrients in plant-accessible forms than the surface fertilized only with digestate or areas fertilized only with standard fertilizers.

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Opportunity of Biogas Production from Solid Organic Wastes through Anaerobic Digestion

E3S Web of Conferences ◽

10.1051/e3sconf/20186505025 ◽

2018 ◽

Vol 65 ◽

pp. 05025 ◽

Cited By ~ 1

Author(s):

Sagor Kumar Pramanik ◽

Fatihah Binti Suja ◽

Biplob Kumar Pramanik ◽

Shahrom Bindi Md Zain

Keyword(s):

Anaerobic Digestion ◽

Biogas Production ◽

Nutrient Balance ◽

Organic Wastes ◽

Organic Loading Rate ◽

Biogas Yield ◽

Carbon And Nitrogen ◽

Potential Risks ◽

Nitrogen Ratio ◽

Pre Treatment

Solid organic wastes create potential risks to environmental pollution and human health due to the uncontrolled discharge of huge quantities of hazardous wastes from numerous sources. Now-a-days, anaerobic digestion (AD) is considered as a verified and effective alternative compared to other techniques for treating solid organic waste. The paper reviewed the biological process and parameters involved in the AD along with the factors could enhance the AD process. Hydrolysis is considered as a rate-limiting phase in the complex AD process. The performance and stability of AD process is highly influenced by various operating parameters like temperature, pH, carbon and nitrogen ratio, retention time, and organic loading rate. Different pre-treatment (e.g. mechanical, chemical and biological) could enhance the AD process and the biogas yield. Co-digestion can also be used to provide suitable nutrient balance inside the digester. Challenges of the anaerobic digestion for biogas production are also discussed.

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Recent variations of calving glaciers in Patagonia, South America, revealed by ground surveys, satellite-data analyses and numerical experiments

Annals of Glaciology ◽

10.1017/s0260305500015974 ◽

1995 ◽

Vol 21 ◽

pp. 297-303 ◽

Cited By ~ 29

Author(s):

Renji Naruse ◽

Masamu Aniya ◽

Pedro Skvarca ◽

Gino Gasassa

Keyword(s):

South America ◽

Mass Balance ◽

Numerical Experiments ◽

Satellite Images ◽

Balance Model ◽

Equilibrium Line Altitude ◽

Simple Mass ◽

Surface Profiles ◽

The Difference ◽

Altitudinal Distributions

Large retreats were revealed for most glaciers in Patagonia, South America, by analyzing satellite images and air photographs. For example, Glaciar O’Higgins retreated 13 km during 41 years from 1945 to 1986 and Glaciar Upsala retreated about 3 km between 1968 and 1990. During the 41 years former period, however, the southern tongue of Glaciar Pio XI advanced by up to 8.5 km and Glaciar Moreno remained almost in a steady state. Considerable ice-thinning rates, from 3.0 to 11 ma−1, were measured by surveying surface profiles in the ablation areas of Tyndall and Upsala glaciers, respectively, during the period from 1985 (or 1990) to 1993. The ice thickness of Glaciar Moreno, however, has changed very little. Numerical experiments using a simple mass-balance model show that a 100 m rise in the equilibrium-line altitude due to climatic change would result in about a 200–350 m rise in the frontal altitude at Glaciar Upsala corresponding to a retreat of 5–8 km, while it would cause only about a 70–100 m rise at Glaciar Moreno. The large difference between these two neighbouring glaciers results from the difference in contributions of the calving amount to the total mass balance, as well as the difference in the altitudinal distributions of drainage areas.

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