A novel use of Moringa oleifera seed powder in enhancing the primary treatment of paper mill effluent Soumia Boulaadjoul a , Hassiba Zemmouri a , Zoubida Bendjama a , Nadjib Drouiche b, * a Laboratoire des Sciences et de Genie des Proc ed es Industriels, Facult e de G enie M ecanique et de G enie des Proc ed es, (USTHB), BP 32,16111 Algiers, Algeria b Centre de Recherche en Technologie des Semi-conducteurs pour l’Energ etique, 2, Bd Frantz Fanon BP140 Alger-7-merveilles, 16038 Alger, Algeria article info Article history: Received 7 October 2017 Received in revised form 17 April 2018 Accepted 20 April 2018 Available online 2 May 2018 Handling Editor: W Mitch Keywords: Alum Coagulation-flocculation M. oleifera Paper mill effluent Primary treatment abstract In this study, Moringa oleifera (M. oleifera) performance as an eco-friendly coagulant in the enhanced primary treatment of paper mill effluent was investigated. Its performance in terms of turbidity removal and COD abatement was examined. Local M. oleifera seed powder from ADRAR-city, South of Algeria, was used. Conventional jar tests were conducted for enhancing the primary treatment of paper mill effluent from paper factory. For this reason, comparative coagulation tests were performed using aluminum sulfate (alum). Indeed, in terms of turbidity abatement, 96.02% and 97.1% were obtained for Moringa and alum, respectively. However, in the case of COD abatement, the abatement rate of M. oleifera seeds was slightly higher than that of alum, 97.28% and 92.67%, respectively. Because M. oleifera is a natural resource that is locally available, an eco-friendly coagulant, non-toxic, and biodegradable and does not affect the pH of water; thus, its use allows to avoid numerous disadvantages of conventional coagulants like alum. © 2018 Elsevier Ltd. All rights reserved. 1. Introduction Generally, paper mill wastewater contains organic and inorganic materials that are sometimes very toxic. Such components are dispersed (colloids) in solution, in suspension or in emulsion (polar molecules) form. Pulp and paper is among the most polluting in- dustries, which cause worldwide environmental damages (Guo et al., 2016). In fact, pulp and paper mill effluent is highly toxic and the major source of aquatic pollution. The chemical composi- tion of the paper mill effluent forms and diversifies according to the different stages of the paper making process: (i) during the pulping process, effluents are enriched by tannins, resin acids, unsaturated fatty acids, diterpene alcohols, juvaniones, chlorinated resin acids, and other chemicals and (ii) during the bleaching stage of the pulp, a large number of pollutants such as chlorate ions, dioxins, furans, chlorophenols, acetone, sulfur and sulfur compounds, and many others, considered as the more dangerous chemicals, are added to the paper mill effluents (Pokhrel and Viraraghavan, 2004). Some of the pollutants, namely polychlorinated dibenzodioxins and di- benzofurans dioxins and furans, are recalcitrant to degradation; (iii) during the final stage, which is related to the use of dyes in printing and staining, heavy metals such as cadmium, copper, zinc, and chromium are added. The chemical composition of paper mill effluent is expressed by the visual color and very high levels of biochemical oxygen demand (BOD) and chemical oxygen demand (COD), due to the presence of lignin and its derivatives from raw cellulosic materials, chlorinated compounds, suspended solids (mainly fibers, fibrils, CaCO 3 , clays), etc. Actually, the elimination of such potential environmental disturbance, in a perspective of sustainable development, is an important target for industrial and developed countries. Indeed, several physical, chemical, and biological techniques such as electro-coagulation (Deepak, 2014), biodegradation (Sharma et al., 2014), moving bed biofilm reactor (MBBR) process (Oliveira, 2014), and nanofiltration process (Beril G€ onder et al., 2011) are used to purify paper mill effluents. In this respect, coagulation-flocculation remains a promising process due to its technical and economic simplicity; coagulation-flocculation is the most frequently used process alone or in combination with other methods for paper effluent treatment (Choudhary et al., 2015). The coagulants most * Corresponding author. Technology of Semi-conductor for the Energetic Research 11 Center Department of Environmental Engineering 2, Bd Frantz Fanon BP140 Alger-7-merveilles, Algiers, Algeria. E-mail addresses: hassiba_zemmouri@yahoo.fr (H. Zemmouri), nadjibdrouiche@ yahoo.fr (N. Drouiche). Contents lists available at ScienceDirect Chemosphere journal homepage: www.elsevier.com/locate/chemosphere https://doi.org/10.1016/j.chemosphere.2018.04.123 0045-6535/© 2018 Elsevier Ltd. All rights reserved. Chemosphere 206 (2018) 142e149