Promoting Actiflo® at the Water New Zealand Conference in Rotorua

This year’s Water New Zealand Conference takes place from 19-21 October in Rotorua and it explores innovative ways to mitigate the range of challenges the water sector faces.

Demographically, New Zealand faces a number of challenges. While some of the regions are facing significant growth, others have reducing populations, an increasing number of residents on fixed incomes, and aging assets. How then can we get on a pathway to excellence? That is what this year's conference is focusing on.

Veolia’s New Zealand team is present with a stand (178-179) and promotes especially its Water business and the Actiflo® technology.
Deborah Rei (Operations Technician, Veolia ANZ) and Stuart Pile (Operations & Project Engineer, Veolia ANZ) present a paper on "Wanaka Drinking Water Actiflo® Trial - Algae Removal in Oligotrophic Water" on day 2.


The Wanaka trial project

In late 2015, Queenstown Lakes District Council (QLDC) commissioned Veolia to trial the Actiflo® process at Beacon Point Intake, which is one of two intakes on Lake Wanaka for the Wanaka drinking water supply. Since 2008, the supply has been experiencing increasing amounts of algae being drawn from the intake into the water supply.

Actiflo® is a compact high rate clarification system developed and patented by Veolia that utilises micro-sand enhanced flocculation (MEF) in conjunction with lamella settlers. The micro-sand particles provide a large surface area and act as a seed for floc formation, whilst also providing ballast which increases the settling velocity of these particles. Whilst this treatment system has been employed at a wide variety of reference sites worldwide, most of these sites experience a turbidity of > 500 NTU.

A completely self-contained Veolia pilot system was used for simulating the operating conditions of a full scale Actiflo® installation. The primary purpose of the trial exercise for QLDC was to determine the suitability of the treatment process for full scale reduction in the amount of algae drawn into the drinking water supply.

A successful demonstration of Actiflo® feasibility was proven during the trial.