JOURNAL OF WATER PROCESS ENGINEERING, cilt.0, ss.1-14, 2020 (SCI-Expanded)
Wastewater
treatment with natural coagulants is an area that is well-researched and
covered in the literature, but new research in this current and ongoing field
is still interesting. The present analysis was conducted as the first study to
investigate the use of Alyssum mucilage as a new, natural, and
cost-effective coagulant for the treatment of synthesized bilge water. To the
best of the authors’ knowledge, no previous study has specifically devoted to
implementing a systematic analysis of a new coagulant (Alyssum mucilage)
within the framework of central composite design-response surface methodology
(CCD-RSM), adaptive neuro-fuzzy inference system (ANFIS), and artificial neural
network (ANN). Thus, to spot the lights over the mentioned gaps, the current
study was undertaken as the first attempt to perform highly comprehensive
mathematical, kinetic, and statistical analyses for a quantitative definition
of the coagulation-flocculation process of oily-saline wastewater treatment
using Alyssum mucilage. In this study, three process-related
parameters, such as coagulant dose, contact time, and pH, were introduced for
modeling, optimization, and cost analysis of the investigated application. At
the optimum conditions (coagulant dose = 40.5 mg/L, pH = 7.05, and contact time
= 34.9 min) of Alyssum mucilage, the maximum chemical oxygen
demand (COD), turbidity (TU), and surfactant removal efficiencies were obtained
as 84.63 %, 96.25 %, and 99 %, respectively. Under the optimum conditions
(coagulant dose = 301.8 mg/L, pH = 6.53, and contact time = 23.1 min) of poly
aluminum chloride (PAC), used as a comparative polymerized metal coagulant, the
maximum COD, TU, and surfactant removal efficiencies were determined as 92.30
%, 99.92 %, and 99 %, respectively. Compared to CCD-RSM, ANFIS and ANN showed
high accuracy with R2 values more than 0.990 for
both PAC and Alyssum mucilage. The kinetic study revealed that
the second-order model performance was superior to the first-order model.
Fourier-transform infrared spectroscopy (FTIR) analysis of Alyssum mucilage
demonstrated that the functional groups presented in the composition of this
coagulant caused coagulation and bonding between the particles. Furthermore,
the zeta potentials of bilge water, coagulant, and treated bilge water indicated
that the possible mechanism of the coagulation would be adsorption and
bridging.