Biogasification of Cassava Residue for On‐Site Biofuel Generation for Food Production with Potential Cost Minimization, Health and Environmental Safety Dividends

Abstract

Convenient energy sources like biomethane and electricity are scarce commodities in cassava producing countries that depend on wood and charcoal for energy supply. Combustion of wood and charcoal releases substances that impair human health. In 2016, about 30 million metric tons of cassava peeling residues (CPR) were generated worldwide and discharged into the environment. Apart from deforestation, loss of biodiversity and soil erosion caused by felling vegetation for wood and charcoal recovery, discharge of CPR into the environment exacerbates environmental pollution and health hazards. This study presented biogasification experiments with CPR in a simple, batch, leach‐bed, unmixed fermentor. Biofuel yield ranged from 180 to 310 (mean of 252) L CH4 kg−1 VS−1 while fermentation time ranged from 19 to 33 (mean of 27) days. The substrate contained on average 33% dry matter of which 96% was volatile, and 71% volatile solids reduction was achieved. Furthermore, all electrical and thermal energy required for producing three cassava root food products (flour, gari, and starch) could be generated on‐site using CPR as substrate for anaerobic digestion. Consequently, energy paucity, environmental contamination, health hazards associated with cassava processing effluent, and combustion of wood and charcoal, could be mitigated by biogasification of CPR. © 2019 American Institute of Chemical Engineers Environ Prog, 38:e13138, 2019

Dialing Back the Doomsday Clock with Circular Bioeconomy

“…One study subjected cassava peeling residue (CPR) derived from 1000 kg of cassava root to AD. Output biogas provided sufficient energy to process the 1000 kg root into flour, gari, and starch [158]. Biogas canceled the global warming potential of fossil energy otherwise required for the production of these products, hence contributing to climate change mitigation.…”

Digestate: The Coproduct of Biofuel Production in a Circular Economy, and New Results for Cassava Peeling Residue Digestate

“…Some results of the research work on CPR as sole substrate for AD were reported earlier. These included proximate properties (e.g., moisture content, total solids, volatile solids), digester performance characteristics (methane content of biogas, pH, discharge effluent COD), feedstock materials, sampling procedures, analyses [94]. Presented in Table 5 are results of nutrient values of liquid fraction of CPR digestate.…”

Principais cadeias produtivas para o desenvolvimento da agroenergia no Norte do Brasil: limitações e perspectivas

“…Entretanto a utilização dos resíduos, como a casca e a parte aérea, podem ser viáveis, mostrando-se como matéria-prima para a produção não somente de etanol, mas também de eletricidade, visto que comercialmente é feito uso somente da raiz da mandioca, seja para consumo in natura ou fabricação de farinha ou fécula (Serra et al, 1978;Boog et al, 2007;Pattiya, 2011;Sivamani et al, 2018). Estudos realizados por Aso et al (2019) estabeleceram que resíduos de cascas, provenientes de 1000 kg de raiz de mandioca, podem gerar energia suficiente para processar 1000 kg de mandioca, tornando a cadeia mais sustentável.…”