Dalby Regional Saleyards: Comprehensive Wastewater Treatment Upgrade for Enhanced Efficiency and Compliance
Dalby Regional Saleyards has been operational for over 80 years and is one of the largest livestock-selling saleyards in Queensland, with world-class features and a prime position for access to the market, selling an average of 200,000 head of cattle each year.
In 2014, to ensure ongoing compliance with stringent local council regulations, the Dalby Regional Saleyards engaged Hydroflux to undertake a comprehensive upgrade of its wastewater treatment system. This upgrade was crucial for maintaining the facility’s high operational standards while adhering to environmental guidelines.
The project involved the design, supply, and installation of a two-stage screening system, a biological nutrient removal (BNR) plant, and an efficient sludge handling facility to manage the byproducts of wastewater treatment. The initial screening system was particularly robust, starting with a coarse 6 mm screen to capture larger debris, followed by a finer 1 mm rotary screen. This two-tiered approach was specifically engineered to handle the substantial instantaneous solids loads generated during the initial washing of trucks and yards, ensuring that even the heaviest flows were effectively managed.
After screening, the wastewater flowed into an in-ground Intermittent Decanted Aeration Lagoon (IDAL), designed to efficiently remove organics and nutrients from the water. The IDAL, with a capacity of 1 ML, was constructed with a double liner to provide enhanced containment and environmental protection. Aeration within the lagoon was accomplished using dual surface aerators, which ensured adequate oxygenation for the biological processes.
The treated wastewater was then decanted from the system using a Hydroflux-designed novel pumped variable depth decanter, which allowed for precise control over the decanting process. Excess waste-activated sludge (WAS) generated from the treatment process was pumped to a sludge storage tank, where it underwent flocculation before being dewatered.
For the dewatering process, a HUBER Q440 screw press was employed, capable of handling very low solids concentrations. This screw press produced a spadable sludge, which was then utilised for composting, further contributing to the facility’s sustainability efforts.
