An eco-biotechnological process for the treatment of residual lemon pulp

Abstract

A biological treatment was designed for lemon pulp waste, a residual product from the lemon processing industry that causes many economic and environmental problems. The technique was carried out in two stages. In the first one, the pulp was treated with microorganisms until reaching partial digestion and increasing pH from 3.8 to neutrality. In the second, the predigested pulp of the first stage was treated with earthworms of the Eisenia foetida variety for 90 days, thus transforming the residue into humus and propagating the earthworms with an individual mean growth of 2.34 mg/day. The process is simple and transforms a highly contaminant solid residue into commercially valuable products like humus and earthworms. Different germination and phytotoxicity assays were performed with assorted seeds to establish humus properties. © Springer-Verlag 2008.