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water Business by the public. However, the community has become increasingly sensitive to fugitive odour emissions from these sources and now regards odour as a major issue affecting quality of life. Odour issues are an ongoing problem for the operations personnel, who have to respond to customer complaints at all hours. Fugitive odour emissions may occur from any of the wastewater conveyance facilities for a number of reasons. At wastewater pumping stations, pressurisation of the headspace occurs above the sewage level in the wetwell with continuous in-flow into the station. Current practices such as plastic-lined wet-wells, access chambers and main sewers have contributed to accumulation and pressurisation of the gases in the collection system, which if not released and treated in a controlled environment will escape elsewhere in the system, such as at covers and access lids that have not been completely sealed. Operations personnel are hard pressed to find a long-term and costeffective solution to control and mitigate the odours. Considerable time and effort is spent in pacifying sometimes irate customers who want an immediate resolution.
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Odouridder & OdaVent
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Biofiltration Systems • Biological treatment of hydrogen sulphide (H2S) and volatile organic compounds • Innovative patented design • Proven H2S removal efficiency >99% • Modular and transportable construction • Small footprint • Low capital and life cycle costs • Long media life (3-5years). No hazardous waste • Environmentally sustainable technology • Complies with WSA121 Industry Standard for Biofilters for Odour Control • Above and below ground systems available
Applications: Control and treatment of foul odours from wastewater pump stations, discharge manholes, air-valve pits, main sewers, treatment plant inlet works
E-mail: info@odatech.com.au www.odatech.com.au
odours….controlled naturally
water august 2015
A range of odour control methods have been tried to address the management of odour emissions from wastewater collection systems, including activated carbon adsorption, ozone treatment, odour-masking agents and bio-trickling filters. However, these treatments all require high levels of ongoing maintenance and incur high ongoing costs, both in terms of maintenance and frequent chemical and/or media replacement for satisfactory treatment levels. Without constant attention, these systems become unreliable and do not solve odour complaints. In addition, many of these odour treatment solutions utilise chemicals or produce byproducts that are not environmentally friendly and must be disposed of. Traditionally, the odour control option with the lowest costs and maintenance requirements were open biofiltration beds. These beds of biologically active mulch and other organic matter would be built over vents from pump stations and treatment plants, allowing the hydrogen sulphide gas to be oxidised by the microorganisms that live in the biomedia before the air is released to the atmosphere. In peak operating condition, these beds were a successful odour control option. However, the treatment conditions in an outdoor biofilter bed are difficult to control – the systems were prone to drying out, causing the death of the microorganisms that treat the odours, as well as causing cracks that provide a “path of least resistance” for the gas – bypassing treatment. In addition, over time the media would compact, eventually completely blocking airflow and leaving the foul air to leak out elsewhere. While working at the Water Corporation in Western Australia), OdaTech Managing Director, Ivan de Souza, noticed the shortcomings of open-bed biofilters and set about attempting to find a more reliable solution that would maintain the low-cost, low-maintenance and environmentally friendly aspects of biofiltration.
Through several prototype units the OdaVent biofilter was born. The fully enclosed biofilter units allow treatment conditions to be tightly controlled for the best possible performance, ensuring the media is in uniform and permeable condition and that airflow is spread evenly through the system. A proprietary biomedia mix is used, specifically designed to avoid compaction and to provide the ideal ecological conditions for the microorganisms. In addition, the patented tiered tray biofilter design prevents water logging and compaction of biomedia and enables a reduction in footprint of up to four times compared to traditional open biofilter beds. Their modular design allows flexible system footprints and flow capacities, depending on what is required. Biomedia replacement is a simple and safe process, and is only required every three to five years. No chemicals are required and no hazardous wastes are created. OdaTech also offers Australia’s only below-ground modular biofilter. The OdaVent MHV can be unobtrusively installed in street verges or on sites where very limited space is available. Between this and the above-ground OdaVent SPSV, OdaTech biofiltration odour control systems can treat odours at water infrastructure facilities ranging from air valve pits to small-tomedium size wastewater treatment plants. OdaTech’s biofiltration odour control systems are specifically designed for odour and corrosion control of sewer infrastructure and achieve best-in-class 99% hydrogen sulphide removal. Over 50 systems have now been installed across Australia for water utilities such as Water Corporation, SA Water, Gold Coast Water, Brisbane Water and Melbourne Water, and private water recycling companies. For more information please go to www.odatech.com.au