Biochars made from pelleted sugar beet pulp for heavy metal remediation.

Abstract

Processing of sugar beet roots for extraction of white refined sugar also yields sugar beet pulp as a byproduct. Traditionally, sugar beet pulp has been used as animal feed for its nutritional worth but other value-added transformations could further improve the economics of sugar beet production.  Thermo-chemical conversion of sugar beet pulp is one such avenue.  This process converts the organic carbon rich pulp into a value-added biochar as the main product, but also produces synthesis gas and bio-oil, two products that could fit into alternative energy frameworks.  This study looks at the physico-chemical and adsorptive properties of pelleted sugar beet pulp biochars produced at four different pyrolysis temperatures: 350, 500, 650 and 800°C for 1 hour residence time and investigated various uses from adsorption/remediation materials to source of fuel and use as soil amendment. Biochars were able to adsorb various heavy metals from solution, particularly lead, chromium and copper. While lower pyrolysis temperature biochars performed better in adsorption experiments, higher temperature biochars were better candidates for fuel applications. Due to their N-P-K composition, biochars from sugar beets also showed potential to be used as soil amendments to enhance soil health and improve crop yields.