In search of the optimal inoculum to substrate ratio during anaerobic co-digestion of spent coffee grounds and cow manure

Akyol, Çağrı

doi:10.1177/0734242x20914731

Cited by 17 publications

(4 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Five AcoD combinations and two inocula were assessed to investigate the mesophilic BMP performance of the local waste. The inoculum-to-substrate ratio I:S did not show biomass inhibition [ 35 ], perhaps due to the high organic content of the inoculum. The reactors were running for 60 days to assure the total degradation of the waste under the selected experimental conditions.…”

Section: Resultsmentioning

confidence: 99%

Promoting the Circular Economy on an Island: Anaerobic Co-Digestion of Local Organic Substrates as a Possible Renewable Energy Source

Fernández-Rodríguez

Berardino²,

Berardino

2023

Microorganisms

View full text Add to dashboard Cite

The local waste co-digestion is an interesting option to tackle in reduced and isolated areas like the islands. The islands have limited territory and scarce fuel production. Moreover, organic waste can create serious environmental problems in soil, water and air. Anaerobic co-digestion (AcoD) is a technology fulfilling the concept of waste-to-energy (WtE) based on local resources. The valorisation of organic waste through AcoD on an island would prevent environmental impacts, while being a source of renewable energy. In this study, cow manure (outdoor and indoor), pig slurry, bird manure, kitchen waste, sewage sludge and oily lacteous waste produced on Island Terceira (Portugal) were tested in mesophilic −35 °C- Biochemical Methane Potential (BMP) co-digestion assays. The goals were to analyse the recalcitrant and high potential produced waste and to estimate the energetic supply source on the island. The cow manure and pig slurry were used as inocula and specific methanogenic activities (SMAs) were carried out. The results showed that both substrates have a significant methanogenic activity–SMA 0.11 g-COD/(g-VSS.d) and 0.085 g-COD/(g-VSS.d), respectively. All the studied combinations were feasible in AcoD, showing TS removals in the range of 19–37%; COD removals in the range 67–78% and specific methane yields from 0.14 to 0.22 L/gCOD removed, but some differences were found. The modified Gompertz model fitted the AcoD assays (R2 0.982–0.998). The maximum biogas production rate, Rmax. was highest in the AcoD of Cow+Pig+Oily and in the Cow+Pig+Sludge with 0.017 and 0.014 L/g-VSadded.day, respectively, and the lowest in Cow+Pig+Bird with 0.010 L/g-VSadded. In our AcoD studies, the bird manure limited the performance of the process, since it was recalcitrant to anaerobic degradation. On the other hand, the oily lacteous waste showed a great potential in the anaerobic digestion. The estimated biogas production, from the best-studied condition, could cover the 11.4% of the energy supply of the inhabitants. These preliminary results would prevent the environmental impact of organic waste on the island and promote the use of local waste in a circular economy scenario.

show abstract

Section: Resultsmentioning

confidence: 99%

Promoting the Circular Economy on an Island: Anaerobic Co-Digestion of Local Organic Substrates as a Possible Renewable Energy Source

Fernández-Rodríguez

Berardino²,

Berardino

2023

Microorganisms

View full text Add to dashboard Cite

show abstract

“…For example, Orfanoudaki et al [28], who studied the anaerobic co-digestion of SCG and pig slurry, found a maximum methane production of 357 mL CH 4 /g VS. In another study [48], a mixture of SCG and cow manure at 1:1 (VS basis) led to 225 mL CH 4 /g VS.…”

Section: Overall Mass Balancementioning

confidence: 96%

The Role of Mild Alkaline Pretreatment in the Biorefinery Upgrade of Spent Coffee Grounds

et al. 2023

View full text Add to dashboard Cite

This work proposes a valorization route for spent coffee grounds (SCG), a widespread lignocellulosic residue, encompassing the production of: biomethane, lignin, and oligosaccharides as value-added products obtained simultaneously during a mild alkaline (NaOH) pretreatment. The studied operational variables were the reaction time (60–240 min), temperature (25–75 °C), and the NaOH concentration (0–2.5 M). The severity factor suitably describes the global process kinetics, with higher severities (log Mo = 5.5) yielding high product yields, 18.02% and 13.25% (on dry SCG basis) for lignin and oligosaccharides (XGMOS), respectively. Solid yield is negatively impacted by all studied variables (at the 95% confidence level). Conversely, XGMOS yield is positively influenced both by time and catalyst concentration, whereas lignin yield is only (positively) influenced by catalyst concentration. Optimal balance between product formation and potential operational costs is putatively achieved when using 0.625 M NaOH, at 50 °C for 60 min. The mild alkaline pretreated biomass (MAP-SCG) was compared to untreated SCG for biomethane production by anaerobic co-digestion with pig slurry (PS), using a ratio of biomass/PS = 1/3 (volatile solids (VS) basis). The proposed valorization route enabled the sequential production of 6.25 kg lignin, 6.36 kg oligosaccharides, and 138.05 kg biomethane per 100 kg of non-extracted SCG (and 287.60 kg pig slurry), in an integrated process that is technically feasible and promotes the circular bioeconomy.

show abstract

“…Nonetheless, this accumulation of VFAs does not always exemplify a pH drop, owing to the buffer capacity of some waste forms. There is an excess of alkalinity in manure, denoting that the VFA growth shall surpass a certain point before it can be determined as a significant change in pH [81]. When the pH in the reactor drops, the concentration of VFAs is possibly very high, and the process may previously have been affected [82].…”

Section: Anaerobic Digestion Phmentioning

confidence: 99%

An Overview of Biogas Production from Anaerobic Digestion and the Possibility of Using Sugarcane Wastewater and Municipal Solid Waste in a South African Context

Tshemese

Deenadayalu

Linganiso

et al. 2023

ASI

View full text Add to dashboard Cite

Bioenergy production from waste is one of the emerging and viable routes from renewable resources (in addition to wind and solar energy). Many developing countries can benefit from this as they are trying to solve the large amounts of unattended garbage in landfills. This waste comes in either liquid (wastewater and oil) or solid (food and agricultural residues) form. Waste has negative impacts on the environment and, consequently, any form of life that exists therein. One way of solving this waste issue is through its usage as a resource for producing valuable products, such as biofuels, thus, creating a circular economy, which is in line with the United Nations (UN) Sustainable Development Goals (SDGs) 5, 7, 8, 9, and 13. Biofuel in the form of biogas can be produced from feedstocks, such as industrial wastewater and municipal effluent, as well as organic solid waste in a process called anaerobic digestion. The feedstock can be used as an individual substrate for anaerobic digestion or co-digested with two other substrates. Research advancements have shown that the anaerobic digestion of two or more substrates produces higher biogas yields as compared to their single substrates’ counterparts. The objective of this review was to look at the anaerobic digestion process and to provide information on the potential of biogas production through the co-digestion of sugarcane processing wastewater and municipal solid waste. The study deduced that sugar wastewater and municipal solid waste can be considered good substrates for biogas production in SA due to their enormous availability and the potential to turn their negative impacts into value addition. Biogas production is a feasible alternative, among others, to boost the country from the current energy issues.

show abstract

In search of the optimal inoculum to substrate ratio during anaerobic co-digestion of spent coffee grounds and cow manure

Cited by 17 publications

References 36 publications

Promoting the Circular Economy on an Island: Anaerobic Co-Digestion of Local Organic Substrates as a Possible Renewable Energy Source

Promoting the Circular Economy on an Island: Anaerobic Co-Digestion of Local Organic Substrates as a Possible Renewable Energy Source

The Role of Mild Alkaline Pretreatment in the Biorefinery Upgrade of Spent Coffee Grounds

An Overview of Biogas Production from Anaerobic Digestion and the Possibility of Using Sugarcane Wastewater and Municipal Solid Waste in a South African Context

Contact Info

Product

Resources

About