Aquis Plaza, Aachen

Grease management – ACO systems for pre-treatment and recovery

Operators of catering and food-processing businesses are obliged to pre-treat trade effluent (e.g. kitchen wastewater). Such wastewater must not be discharged untreated into the public sewer. ACO separation technology removes fats, which otherwise cause odours and damage to pipes and sewers.

Grease separators working on the gravity principle (density difference)—heavy constituents settle, light substances (animal oils/fats) rise—provide the required pre-treatment in most cases. For wastewater treatment, the planners chose proven ACO Passavant products.

Grease-laden wastewater from kitchen and food-prep areas must be pre-treated using grease separators to DIN EN 1825 and DIN 4040-100 so that fats and oils are retained before the wastewater is discharged to the sewer. Wastewater collected via floor drains is therefore first taken up by several installed grease separators of the types ACO Hydrojet OAE and ACO Hydrojet RAE in the basement.

The Hydrojet OAE separators, made of polyethylene and available up to NS 10, are controlled by state-of-the-art technology. Program-controlled, odourless disposal and cleaning are performed via discharge pumps and hydromechanical high-pressure internal cleaning (175 bar)—requiring only a cold-water connection. The ACO Hydrojet RAE separators, also in polyethylene, offer the advantage of segment construction, making them easy to transport and bring into the building even in large nominal sizes.

Preventing backwater – ACO systems for retaining wastewater

Because the building-services plant rooms in Aquis Plaza are located below the backwater level, the rooms must be protected against sewer backflow. This is achieved using lifting stations. When the public sewer is overloaded, a mixture of rainwater, domestic and industrial wastewater can flow back into the building through sanitary fixtures without backflow protection, flooding adjacent rooms. ACO lifting stations prevent backflowing water from damaging the building and equipment.

Pumping, backflow-free discharge and reuse – ACO lifting stations and pump stations

The grease separator systems are located in the building’s basement, i.e. below the backwater level, so a lifting station is required to discharge the oil- and fat-free wastewater to the public sewer. The planners selected the ACO Muli-PE-K duo lifting station.

Designed for free-standing installation, the unit complies with DIN EN 12050 (lifting stations for blackwater) and features two pump assemblies and a cutting system that macerates residual solids. Thanks to high-quality technology and equipment, media with temperatures up to 60 °C can be pumped to heads of 2 to 24 m, with flow rates between 5.93 and 1.2 l/s.

Ceiling penetrations to suit requirements

ACO pipe penetrations route service pipes (media pipes) for water, power, gas and ventilation through building elements requiring sealing. The service pipes are led through sleeve pipes. Building waterproofing is achieved via a compression sealing flange on the penetration, or optionally via a thin-bed flange for alternative waterproofing. In Aquis Plaza, many areas had special structural requirements, so the penetrations had to be individually designed and manufactured. As a rule, sleeve pipes up to DN 200 are used. Flange widths start at 60 mm, but can be specified larger as required.

Conclusion

The drainage concept for the building services and outdoor areas of the Aquis Plaza shopping centre demonstrates that a holistic approach to collecting, cleaning, retaining and discharging water can be realised with system products from the ACO Haustechnik System Chain. Its four building blocks stand for future-oriented drainage solutions. The planners’ decision in favour of ACO Haustechnik was not only based on individual high-quality products, but also on ACO’s ability to provide the complete building drainage—from roof to basement.