Optimization Study of a Wastewater Chemical Treatment With Ponilit Gt-2 Anionic Polyelectrolyte

Abstract

This paper discusses the applications of synthetic PONILIT GT-2 anionic polyelectrolyte for chemical wastewater treatment. Synthetic wastewaters with different colloid concentrations were prepared and the flocculation process followed by sedimentation and/or filtration was studied. Variables concerning the chemical wastewater composition, temperature, mixing time, and flocculants dose are considered in order to appreciate the process efficiency (e.g., turbidity, color and organic matter removals). The removal degrees of turbidity and color are important (>80%) and, respectively, acceptable for organic matter expressed by Chemical Oxygen Demand (COD removal <45%). An empirical model was elaborated by a third order rotatable design 2 3 type, considering temperature, polyelectrolyte dose and mixing time as independent variables, while the turbidity and color removal efficiencies were chosen as optimization criteria. The mathematical 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 efficient chemical wastewater treatment using PONILIT GT-2 anionic polyelectrolyte as flocculation agent.

Textile Wastewater Treatment on a Spinning Disc Reactor: Characteristics, Performances, and Empirical Modeling

“…As response functions or optimization criteria, the removal degree (Y, [%]) in terms of suspended solids (Y 1 ) and color (Y 2 ) were selected. The modeling was organized according with the experimental planning used in an "n" variable active central composite rotatable design where the mathematical model is expressed by Equation (2), with no excessive experiments in comparison with the number of coefficients to be determined (i.e., n = 20, consisting of 2 3 factorial experiments (each corner of cube), 2 × 3 axial experiments (on axes, distance of ±α from center of rotation, α = ±1.682), k = 6 (experiments in the center of variation field, for the independent estimation of "pure" experimental error variance, data reproducibility) [30][31][32][33].…”

“…where Y is the response function (removal degree, [%]); X i or X j is the coded selected variable in the SD treatment system (n = 20); i, j = 1 or 2; b 0 , b i , b j , b ij are the model coefficients. The model coefficients are estimated using statistics for the processing of the experimental results obtained in the central points of the central composite rotatable design, according to the equations presented in previous reports [30,31].…”

“…In the active central composite rotatable (2 3 ) design, a basic value z i0 and a variation step ∆z i0 of each independent variable z i (flowrate, rotational speed, or operating time) were established. The coded value of z i , denoted as X i , was determined with Equation (3) [30,31,33]:…”

“…Thus, after each studied variable variation field was established, an experimental design respecting the active central composite rotatable 2 3 design was applied in the laboratory spinning disc setup for textile wastewater treatment. Rigorous empirical modeling and monitoring methods are becoming very important in each industrial wastewater treatment system, as reported in several studies [27][28][29][30][31].…”

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

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