Particle counter as a tool to control pre-hydrolyzed coagulant dosing and rapid filtration efficiency in a conventional treatment system

Abstract

Filtration efficiency in a conventional water treatment system was analyzed in the context of pre-hydrolyzed coagulant overdosing. Two commercial coagulants of different aluminum speciation were tested. A study was carried out at a water treatment plant supplied with raw water of variable quality. The lack of stability of water quality caused many problems with maintaining the optimal coagulant dose. The achieved results show that the type of coagulant had a very strong influence on the effectiveness of filtration resulting from the application of an improper coagulant dose. The overdosing of high basicity coagulant (PAC85) caused a significant increase of fine particles in the outflow from the sedimentation tanks, which could not be retained in the filter bed due to high surface charge and the small size of hydrolysis products. When using a coagulant of lower basicity (PAC70), it was much easier to control the dose of coagulant and to adjust it to the changing water quality.

Optimizing coagulant choice for treatment technology of surface water for human consumption

“…Coagulation is a process commonly used in water treatment, especially for surface water. This process aims to effectively remove organic matter [1,2] especially precursors of oxidation and disinfection by-products [3][4][5], whose creation potential is related to absorption values at 254 nm (UV 254 ) [6]. Due to a very large variability in surface water composition over the course of the year and different contamination levels dependent on water source location, it is important to optimally choose coagulant type and dosage.…”

Potential application of natural coagulant extraction from walnut seeds for water turbidity removal

“…This procedure generates highly positive and larger coagulant particles (Zin et al 2015;Rosinśka & Dabrowska 2021). The advantages of pre-hydrolyzed coagulants over conventional coagulants are the higher effectiveness with less dependent on the pH and temperature (Guminśka & Kłos 2015;Dabrowska 2018).…”