ABSTRACT
The reduction of turbidity (TUR), salinity (SAL), and colour (COL) from land-based saline aquaculture effluent (LSAE) using Parkia biglobosa seeds coagulant (PBC) was analyzed. The coagulant obtained from the seeds by the salt extraction technique was analyzed for its morphological and spectral characteristics through SEM and FTIR. The effects of PBC dosage (0.1–0.5 g/L), pH (2–10), temperature (303–323 K), and settling time (0–60 minutes) on the reduction of pollutants were examined. The coagulation-flocculation kinetics of the process was also studied in terms of total dissolved and suspended solids (TDSP). The seeds were found to contain 37.9% protein which shows its usability as a coagulant for solids/particles reduction via adsorption/charge neutralization. Maximum removals of TUR = 80.44%, SAL = 79.98%, and COL = 54.47% were obtained at 0.3 g/L, pH 2, 60 minutes, and 303 K. The data fitted into the second-order perikinetics theory by von Smoluchowski (with R 2 > 0.8). At the optimum conditions, the reaction rate (K m) and coagulation-flocculation half-life ( https://www.w3.org/1998/Math/MathML"> [ TOC or COD ] removal ( % ) = [ TOC or COD ] before treatment − [ TOC or COD ] after treatment [ TOC or COD ] before treratment × 100 https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781003185437/4cabc8e5-10c7-4478-8eef-3d0cee9d6842/content/C017_equ_0001.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/> ) were evaluated as 0.0002 L/g.min and 42 minutes, respectively, at coagulation order (α):2. Also, the total cost of employing PBC for the treatment of 1 L of LSAE was estimated as 3.73€ including material, energy, and labour costs. In summary, these seeds can be applied for the pretreatment of LSAE.
