EFFICACY OF TREATING WASTEWATER FROM WASTEPAPER RECYCLING MILL USING A BLEND OF Moringa oleifera Lam AND SYNTHETIC COAGULANTS

Abstract

Wastepaper recycling is an imminent industry globally to cater for the growing demand for paper and related paper products. The wastepaper recycling industry is characterized by high concentrations of pollutants and toxic components emanating from defibering, deinking and papermaking processes. Inefficient treatment of the effluent from the mills would negatively impact the receiving water ecosystems and health of their users. This study focused on determining the efficiency of treating wastewater from a wastepaper recycling mill by blending Moringa oleifera Lam plant parts with some synthetic coagulants. The Moringa oleifera plant parts tested include fatted seed (FMos), defatted seeds (DMos) and bark (BMo), whereas chemical coagulants used were aluminium sulphate (alum) and polyaluminium chloride (PAC). Firstly, effective doses of individual and blended coagulants were established. Thereafter, efficacy of treatment and microbial load reduction of wastewater from wastepaper recycling using the effective doses for both individual and blended coagulants were determined. Samples of wastewater were obtained from Maz International Paper Mill, using grab sampling method. A completely randomized design was applied, to achieve the objectives of the study. A standard jar test procedure was used to determine the effective doses of individual and blended coagulants, whereas standard APHA procedures were employed to determine the efficacy of the treatment and reduction of microbial load from the wastewater. The data obtained was displayed in tables and figures where appropriate and analyzed using descriptive statistics and one-way ANOVA. The study revealed that effective doses were DMos; 32g/L (144.0NTU), FMos; 36g/L (250.2NTU), BMo; 80g/L (881.0NTU), alum; 1.5g/L (24.1NTU), PAC; 6.6g/L (162.2NTU), DMos/Alum; 20/80% (17.1NTU), FMos/Alum; 30/70% (25.2NTU), DMos/PAC; 70/30% (93.6NTU), and FMos/PAC; 70/30% (110.4NTU). However, there was no synergy noted for blending BMo/Alum and BMo/PAC. The various effective doses resulted in the reduction of wastewater pollution parameters wastepaper recycling mill. Among the individual coagulants’ alum was most efficient whereas among the blended coagulants DMos/Alum was the most efficient. The blend of DMos and alum effectively treated wastewater from wastepaper recycling mill, by significantly reducing the BOD, color, TDS, EC, and TSS to 28.7 mg/L, 14.4 PCU, 267.8 mg/L, 495.6 μs/cm, and 5.8 mg/L, respectively. These final DMos/Alum treated parameters were within WHO, NEMA, and USEPA permissible drinking water thresholds. Additionally, the DMos/Alum blend resulted in the highest microbial load removal by 99.2%. This study shows, the wastewater from wastepaper recycling mill can be effectively treated using the blend of DMos and alum. Therefore, recommend that a blend of DMos and alum be applied in treating wastewater from wastepaper recycling mills.