These filtration methods are used in the treatment of industrial effluent, process water, municipal wastewater and drinking water, as well as in water reuse applications. They are also used as pre-treatment steps to membrane filtration processes and desalination of seawater. In addition to the array of conventional filtration products and technologies such as screening; sand filtration, gravity filtration, activated carbon filtration and membrane separation used in its water treatment processes, Veolia South Africa also makes use of reverse osmosis (RO).
RO is a filtration method used to separate molecules and ions from water and is generally used to produce potable, ultrapure and process water. High quality reverse osmosis membranes are manufactured by Veolia specifically for this type of filtration, and they can be used in Veolia’s package plants for potable water treatment and wastewater treatment.
Filtration Media & Systems
Veolia Standard Filtration Products
Berkal™ disc filtration systems
For removing contaminants like fibres, grit sand and algae, these filtration systems achieve high flow rates of 10 to 120 m3 an hour. Berkal disc filters are compact with high retention capacities and are available in filtration grades of 20, 50, 100, 0130, 200 and 400 microns.
Some of the benefits are:
- Automatic backwashing of individual filters based on time or pressure differential
- A flexible modular design with high scalability
- High contaminant removal rates
- Air assisted backwashing
- Corrosion-resistant pipework
- Low running costs and minimal maintenance
Designed to help prevent wear and corrosion of downstream pipe work, components and connected equipment, these filters achieve flow rates of 4.3 to 100 m3 an hour. Ideal for industrial and domestic applications.
- A 100 micron filter that removes sand, oxidants and dissolved sediments
- Continual flow even during backwash
- A fixed filter with no consumables and minimal maintenance
- Manuel and automatic backwash options
- Corrosion resistance
A mechanical, self-cleaning filter with a large filter area in a small footprint. Solids are caught on the inside of the filter panels mounted on the two sides of the disc segment. This impedes the water flow through the disc causing their inner water levels to rise, which triggers a level sensor which actuates the disc rotation and a backwash cycle begins. The backwash requires only 0.05 to 3% of the total filtered water flow.
The Discfilter series consists of 5 Hydrotech products:
- 2600 Series: The Hydrotech HSF2600 offers you up to 230 m2 of filtration area.
- 2200 Series: The plastic disc design on this series provides considerably lower weight and 50% more filter area per footprint compared to the Hydrotech stainless steel Discfilters.
- 1700, 2100 & 3100: A full range of microscreen filters with flow capacity up to 1 000 l/s (3 600 m3/h) per filter and filter opening range of 10-100 microns.
IDRASCREEN™ represents the range of high capacity self-cleaning screen filters for wastewaters pre-treatment. They are equipped with an inner washing system with low/medium pressure to do periodical cleaning in order to avoid clogging, reducing cleaning, maintenance and high costs.
A few of the advantages are:
- Low investment and installation costs and low operating costs
- High capacity with reduced dimensions
- Low power costs and zero additional water required
- More efficient separated solids draining than traditional filters
- Lower costs for screen removal and recycling
Veolia’s available filters and their configurations
AF-Belt™ Twin Wire Press
Aquaflow’s AF-Belt™ Twin Wire Press is specifically designed for pulp and paper mill sludge dewatering applications and applications where sludge inlet consistency and quality vary, as well as for sludge mixtures with significant bio-sludge content.
Especially designed for Pulp and Paper sludges, the size and geometry are chosen on the basis of sludge properties. It is possible to handle sludges from 5 BDt/d up to 140 BDt/d with one line thanks to a wide size range and tailor-made process design.
The Dusenflo™ gravity filter is a proven efficient and reliable filtration system which offers a unique, economical and highly effective potable water filtration system that provides consistent high-quality, crystal clear potable water.
Eliminator™ Cartridge Filters
Eliminator™ Cartridge Filters are designed to reduce particulate matter from water, either as part of a water purification system or as a stand-alone filtration unit. They produce up to 22 m3/hr of filtered water for a wide variety of process water and general manufacturing applications.
Used to remove particles larger than 0.5 microns from streams with up to 150 mg/l of solids, this robust filtration technology from Veolia uses fixed leaves featuring a central drainage element and a fine outer mesh of wire cloth. This design, when combined with a filter medium such as diatomaceous earth, produces high-quality effluents that often need no further treatment. Filtra-Matic™ can be configured in either a retracting tank shell or retracting bundle designs for easy maintenance and leaf replacement.
FILTRAFLO™ PACK constitutes a complete range of modular and flexible skid-mounted media pressure filters for municipal and industrial applications such as drinking water treatment, process water production and treated water reuse. The municipal product range makes use of Multilayer Filtration technologies and the industrial range uses FILTRAFLO™ Industrial Range. Flow rates for the former are from 10 to 100 mᶟ/h per unit and for the latter from 1 to 90 mᶟ/h per unit.
FILTRAFLO™ PACK (Mono/Duo/Trio) pressure sand filters
These are pressure sand filters that reduce turbidity from water for drinking water treatment, cooling water, pre-filtration for RO systems, filtering surface water, wastewater treatment and reuse and recycling. The skid-mounted units are ready to connect and combine to treat different flows and loads. These units produce from 25 to 100 m3/h per unit, have fully-automated operation via remote control and are easy to integrate into an existing plant.
Filtraflo™ filters are multiple function filters incorporating physical, biological and chemical functions as well as physical-chemical functions. They employ the same basic principle that involves a rapid gravitational filtration of raw water through a granular media, and the filtering bed is composed of single or dual media layers.
A Veolia Water Technologies patent, Filtraflo™ Carb combines physical filtration of suspended solids with adsorption of organic matter into one treatment using micrograin activated carbon. It is a chemical free polishing solution involving micrograin activated carbon that allows the removal of natural organic matter, the pesticides, and a large spectre of micro-pollutants by adsorption in treated water while filtering it.
Designed for effective removal of oil and suspended solids from seawater, cooling water and oil field brine, HRD™ distribution systems control velocity and hydraulic balance, protecting the media during high flow rates of up to 285 litres per minute per square meter of filter area. The systems are pre-engineered to comply with stringent specifications and are delivered assembled in a packaged skid, mounted with piping, valves and controls. HRD™ can combine multiple media options such as silica sand, garnet and anthracite coal for achieving unparalleled filtration efficiency that produces effluent quality with solids content below 1 mg/l in a wide spectrum of low-solids applications. HRD™ is also ideal for treating industrial water streams in the mining, refining and petrochemical sectors – and sewage effluents after tertiary treatment where conventional sand filters are not effective.
Hydrotech Microscreen filters
Hydrotech Drumfilters and Discfilters are cost-effective, have low energy consumption and an automatic control to optimise capacity. They’re available in 500 different variations and can, therefore, be used in applications like industry, municipality, aquaculture, swimming pools and aquariums.
Made for efficient filtration and draining of sludge and wastewater, the Hydrotech Beltfilter is is an automatic, self-cleaning filter specially designed to achieve optimal performance in systems where high solids content in dewatered sludge is essential.
A mechanical and self-cleaning filter that operates in 3 simple steps, the Hydrotech Drumfilter is specially designed for high performance in systems where it is essential to prevent particles from fragmentation.
Designed for the conveyance and dewatering of various types of wastewater screenings, Indrapress™ is capable of drastically reducing the screenings weight and volume, and consequently the transport and disposal costs.
PowerClean® filters, with superior design and long filtration runs, are among the most advanced nutshell filtration technologies available, removing 98% of all suspended solids and insoluble hydrocarbon particles above 5 microns. They are simple, automatic systems designed to eliminate filter plugging problems without the use of air or gas for particulate removal. This is achieved through a quick media cleaning cycle that generates minimal volumes of backwash wastewater.
Veolia South Africa has an established record of success in designing, constructing and commissioning activated carbon plants. With its in-house specialists and access to global resources and knowledge, the company has reference plants in industrial, pharmaceutical, food and beverage, petrochemical, metallurgical and municipal applications.