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Strategies for enhancing methane production from coffee pulp via co-digestion, urea supplementation, and biochar-assisted process stabilisation
(Elsevier Ltd., 2026-07-28) Mahamoud, Seleman; Mshandete, Anthony; Ghofrani-Isfahani, Parisa; Kivaisi, Amelia; Machunda, Revocatus; Irini Angelidak
Coffee pulp (CP), a lignocellulosic agro-industrial residue rich in organic matter, contains phenolic compounds and other constituents that can limit anaerobic digestion (AD) performance. This study evaluated semi-continuous AD of CP in continuously stirred tank reactors under mesophilic conditions (37 °C), comparing co-digestion with coffee wastewater (CWW) and sisal wastewater (SWW) against CP mono-digestion. Co-digestion achieved stable reactor performance, with methane production rates of 564 ± 89 and 624 ± 92 mL CH4/L/day and methane contents of 56–59%. This improved performance was associated with enhanced nutrient balance (C/N = 23.8), dilution of potential inhibitory compounds, and low VFA concentrations (<1 g/L). In contrast, CP mono-digestion resulted in process instability, characterised by reduced methane production, VFA accumulation (>1.5 g/L), pH decline, and nitrogen limitation (TAN = 56.0–64.8 mg/L). Urea supplementation restored nutrient availability and reactor stability, resulting in methane production of 343 ± 18 mL CH4/L/day. Although combined urea and biochar supplementation supported recovery (326 ± 26 mL CH4/L/day), the independent effect of biochar could not be isolated, and biochar did not prevent instability at increased organic loading rates. Batch assays further showed that inoculum adaptation enhanced initial methane production kinetics, whereas cattle manure inoculum achieved the highest final methane yield (328 ± 8 mL CH4/g VS). Overall, co-digestion with agro-industrial wastewaters represents an effective strategy for improving CP digestion, while maintaining adequate nitrogen availability is critical for stable CP mono-digestion.
Mechanical and physical properties of steel fibers and banana fibers.
(PLOS One, 2026-03-05) Hepautwa, Amani; Hilonga, Askwar; Mrosso, Register; Tusekile Alfredy; Mwalusambo, Gabriel; Lesafi, Fina; Jande, Yusufu
Mechanical and physical properties of steel fibers and banana fibers.
Raw data on forage species diversity and invasive and or forage species seedbank
(Zenodo, 2026-03-06) Ngondya, Issakwisa
Raw data on forage species diversity and invasive and or forage species seedbank
Raw data on forage species diversity and invasive and or forage species seedbank
(Zenodo, 2026-03-06) Ngondya, Issakwisa
Raw data on forage species diversity and invasive and or forage species seedbank
Questionnaire for Rainwater Harvesting (RWH) and Soil Moisture Conservation (SMC) Technologies in Maize Production in Babati District, Tanzania
(Zenodo, 2026-03-26) Kanyiru, Mary; Meya, Akida; Mkindi, Angela
This dataset contains the semi-structured guide for surveys, interviews and focus group discussions used to collect data on rainwater harvesting and soil moisture conservation technologies used in maize production in Babati District, Tanzania.