Using a Pulsed Electric Field as a Pretreatment for Improved Biosolids Digestion and Methanogenesis

Abstract

We tested the ability of a pulsed electric field (PEF) technology to enhance solubilization of organic material in waste activated sludge (WAS) and pig manure, with the goal of making it more bioavailable for methane production during subsequent anaerobic digestion. We varied PEF operating parameters across an approximately 10-fold range, showing the influence that the amount of treatment has on solubilization, as measured by soluble chemical oxygen demand (SCOD), and methane production, as gauged by the biochemical methane potential. Once PEF treatment exceeded a threshold, SCOD increased by an order of magnitude (to over 1000 mg/L), which resulted in a doubling of methane production for WAS. We obtained similar findings for pig manure, with SCOD increasing 3-fold due to PEF pretreatment and methane production increasing by 80%. These results support that PEF pretreatment before anaerobic digestion can significantly improve digester performance, resulting in added methane production and decreased residual biosolids.

Effects of pre-treatment technologies on dark fermentative biohydrogen production: A review

“…Besides, most studies employing ultrasound irradiation as either substrates or inoculum pre-treatment have only focussed upon some of the optimum conditions while often neglecting the energy requirement of pre-treatment which frequently exceeds the positive increases in H 2 yields. Additionally, the use of ultrasound irradiation on large scale has provided insignificant benefits so far (Salerno et al, 2009). Consequently, in order to effectively and efficiently use this pretreatment technique, the energetic, economic and technical aspects need to be investigated on both lab-, pilot-and large-scales.…”

Effects of pulsed electric field treatment on enhancing lipid recovery from the microalga, Scenedesmus

“…While circumventing environmental toxicity, these approaches have achieved comparatively lower yields, although pre-treatment has After transport to the Swette Center for Environmental Biotechnology (SCEB) on ASU's Tempe campus, the sample was subjected to FP treatment with the alpha unit at a treatment intensity of 30.6 KWh/m3; this is called 1-pass treatment (Salerno et al, 2009). A portion of the sample that was collected from AzCATi was not subjected to treatment and was the control sample.…”

Effects of pre-fermentation and pulsed-electric-field treatment of primary sludge in microbial electrochemical cells

“…A fraction of the collected PS was pre-treated with PEF using the Focused Pulsed Ò (FP) alpha unit (OpenCEL/Trojan Technologies, London, ON, Canada) located at the Swette Center for Environmental Biotechnology Salerno et al, 2009). The PS was diluted $1.3-fold with distilled water to achieve a conductivity of 0.175 mS/cm, and we applied a treatment intensity of 33 kWh/m 3 during PEF treatment (Salerno et al, 2009). Control and PEF-treated PS were stored in a 4°C cold room and used as feedstock for semi-continuous fermentation experiments.…”