Abstract

OVIEDO-OCANA, Edgar Ricardo; MARMOLEJO-REBELLON, Luis Fernando  and  TORRES-LOZADA, Patricia. Evaluation of the Addition of Wood Ash to Control the pH of Substrates in Municipal Biowaste Composting. Ing. invest. y tecnol. [online]. 2014, vol.15, n.3, pp.469-478. ISSN 2594-0732.

This study evaluates the addition of wood ashes (WA) for controlling the pH of substrates in municipal biowaste (MBW) composting. Three combinations in wet weight percent (w/w) of MBW and WA were tested: i) BC₁: 2% WA and 98% MBW; ii) BC₂: 4% WA and 96% MBW; and iii) BC₃: 8% WA and 92% MBW. Each combination was compared with a control (100% MBW) called B₁, B₂ and B₃ respectively. The experiment was conducted to pilot scale, with piles of 510 kg. The results indicate that the addition of WA improved the pH level and nutrients for the composting process; however, it had not substantial benefit in the process (start of the thermophilic phase and the behavior of the substrate degradation rate). Furthermore, a higher presence of salts and phytotoxic compounds in the product was observed. This could limit the product use for agricultural activities.

Keywords : biowaste; composting; amendment materials; wood ash.