Bioconversion of Dried Leaves from Algerian Date Palm (<i>Phoenix dactylifera</i> L.) to Biogas by Anaerobic Digestion

Abstract

This work aimed to study anaerobic digestion of a new substrate made from the waste of Algerian date palm (Phoenix dactyliferaL.) in order to evaluate its biogas production capacity. The lignocellulosic component biodegradability and the process stability were also tested. Two reactors were launched with the same concentration of 20g total solid (TS)/L. A physical pre-treatment (grinding) of dried leaves lowered the substrate size below 2 mm. The theoretical methane yield (499 - 538 mL CH4/g of Volatile Solids (VS)) indicated a high substrate methanogen potential. The tested methane and biogas yield reached 130±6 mL CH4/gVS and 197±6 mL/g VS respectively. The biodegradability through the volatiles solid reduction was 29%. The total alkalinity (TA) value increased from the beginning to the end, due to the substrate nature which gave a high buffering capacity of the medium. During the stable process, a higher Chemical Oxygen Demand (COD) removal was reached with a value of 77.58%. The majority of the biogas yield was generated during the same period, which confirmed that the anaerobic digestion process stability is indispensable. Finally, this study was an opportunity to better exploit local by-products for the bioenergy production.

Valorization of Date Waste (Hmira Cultivar) for the Production of Bioalcohol and Biogas

“…After the fifteenth day we notice the stability of pH between 7 and 7.5 (optimum value for anaerobic digestion). This stability is caused by the decrease of volatile fatty acids concentration and the depletion of organic matter in the media (Djaafri et al, 2019). Volatile fatty acids (VFA) and volatile organic acid and buffer capacity (TAC) ratio Figure 8 showed that with the three concentrations and control sample the VFA / TA ratio begins near 1 in the first two days and begins to increase until exceeding 2 which is explained by the presence of the significant amounts of accumulated VFA, their accumulation influences negatively on the course of the anaerobic digestion (Kaidi et al, 2020).…”

A Route for Bioenergy in the Sahara Region: Date Palm Waste Valorization through Updraft Gasification

“…The Adrar region has a great biomass potential, made up mainly of date palms (Phoenix dactylifera L.), covering about 27,804 hectares, with a total of 3,978,800 palms [8]. Every year, at the beginning of the new agricultural season, the palms are subjected to a maintenance and cleaning process that produces huge quantities of lignocellulosic biomass, between 10 kg/palm and 65 kg/palm, depending on the species [9][10][11][12]. Unfortunately, this biomass is undervalued.…”