Study of flocculation with PONILIT GT-2 anionic polyelectrolyte applied into a chemical wastewater treatment

Abstract

This paper discusses the applications of synthetic PONILIT GT-2 anionic polyelectrolyte in conjuction with ferric sulfate in a chemical wastewater treatment viz. wastewater from ceramics manufacturing. Synthetic wastewaters with different colloid concentrations were prepared and the coagulation-flocculation process followed by sedimentation and/or filtration was studied. Variables associated with the chemical wastewater composition, mixing time, and the coagulant and flocculant dose are considered in order to appreciate the process efficiency in terms of turbidity, chemical oxygen demand (COD), and color removal. The degrees are higher for turbidity and color (> 80 %) removal respectively, and, satisfactory for COD (< 50 %). An empirical model was elaborated by a third order rotatable design 2 3 type, considering ferric sulfate dose, polyelectrolyte dose, and mixing time as independent variables, while the turbidity and color removal efficiencies were chosen as optimization criteria. The empirical model was found adequate for the chemical wastewater treatment. Also, an analysis of the model was performed to find the optimal operating conditions, in order to apply this process for an efficient chemical wastewater treatment using ferric sulfate as coagulation agent and PONILIT GT-2 anionic polyelectrolyte as flocculation agent. The optimal values correspond to a ferric ions concentration of 6.093 mg/L, a polyelectrolyte dose of 0.651 mg/L, and a mixing time of 24.024 minutes for turbidity removal (95.869 %), respectively, and, to a ferric ions concentration of 6.01 mg/L, a polyelectrolyte dose of 0.69 mg/L, and a mixing time of 26 minutes for color removal (98.741 %).

Preparation of quaternized carboxymethyl chitosan and its capacity to flocculate COD from printing wastewater

“…Flocculation is a method with highly effective, inexpensive, and easy to operate among the physicochemical treatment processes of wastewater. Consequently, numerous low-cost flocculants have been studied including polyacrylamide (PAM) and its modifying derivatives, [10][11][12] polyaluminum chloride (PAC), 13 polymerized ferrous sulfate (PFS), 14 aluminum sulfate (AS), [15][16][17] modifying polysaccharides, 18,19 etc.…”

Efficient Removal of Reactive Orange 107 Dye from Aqueous Media by Shrimp Shell Derived Chitosan Functionalized Magnetic Nanoparticles

“…[6]- [13]. However, most of them are restricted by their high initial and operational costs [14] [15] [16] [17] [18]. Adsorption is considered to be a promising method for such applications because of its ease of operation, simplicity, high recovery, low cost and non-toxic products [19].…”

Textile Organic Dyes – Characteristics, Polluting Effects and Separation/Elimination Procedures from Industrial Effluents – A Critical Overview

“…The immediate result of this coprecipitation is the almost instantaneous production of very small coloured particles, having little strength and breaking down at any significant disturbances. The agglomeration of the coloured precipitates by using appropriate high polyelectrolyte flocculants produces stable flocs (Zaharia et al, 2007(Zaharia et al, , 2011. The main disadvantages of this treatment are the process control that is a little difficult, the potential affection of precipitation rate and floc size by impurities such as non-ionic detergents remaining in the effluent, and the sludge production which has to be settled, dewatered and pressed into a cake for subsequent landfilling tipping.…”

“…These chemicals cause destabilisation of colloidal and small suspended particles (e.g. dyes, clay, heavy metals, organic solids, oil in wastewater) and emulsions entrapping solids (coagulation) and/or the agglomeration of these particles to flocs large enough to settle (flocculation) or highly improve further filtration Zaharia et al, 2007). In the case of flocculation, anionic and non-ionic polymers are also used.…”

“…Some applications of coagulation-flocculation in wastewater treatment (adapted from Zaharia, 2006;Zaharia et al, 2006Zaharia et al, , 2007.…”