Solutions for combined sewer systems

In cooperation with our partner, we handle the entire range of works – from design to implementation and service of these devices. 

The application of high technical standards in HST products and the openness and flexibility for other systems within the remote control and management technology are of significant value, ensuring the safety of investments and supplier independence for all solutions. HST products feature IT systems and automation with process intelligence that minimises the need for external energy to operate the unit. 

A grate designed for installation on storm overflows of combined sewer systems, protecting against the discharge of solid floating pollutants (sanitary products, among others) into the receiver. 

Application:

• storm overflows of combined sewers,
• storage reservoirs for combined sewers.

Technical data:

• Height: 0.45 – 1.70 m
• Length: 2.50 – 9.00 m
• Capacity: up to 9 m³/s per module
• Slot: 4-8 mm
• Type of drive: electrohydraulic
• Drive power: 2.2 – 5.5 kW
• Material: stainless steel / composite

Application:

• retention tanks
• combined sewers

Above the section requiring flushing, a chamber with a drainage outlet closed with a gate is placed. When the reservoir is drained, the flushing water is retained in the chamber and the flushing process takes place once the reservoir has been drained. 

Advantages:

• reliable opening and closing system,
• sealing with a pressing system,
• thanks to the lightweight body, no additional delayed closing mechanisms are required, leading to low hydraulic losses and complete emptying of the chamber.

Technical data:

• Height: 0.40 – 0.80 m
• Width: 0.50 – 5.00 m
• Type of drive: electrohydraulic
• Drive power: 0.75 – 2.2 kW
• Material: stainless steel / composite

The flushing trough allows the bottom of the tank to be repeatedly flushed of accumulated sludge. The asymmetrical cross-section ensures that the trough rotates and empties shortly before being fully filled. The emptying of the trough, which is positioned 2–4 m above the bottom of the reservoir, creates a strong flushing wave that safely washes away the accumulated sludge. 

Advantages:

• installed above the maximum water level
• automatic trough filling
• flushing using wastewater from the tank
• relatively small volume of water needed for flushing
• low energy costs for filling troughs
• low maintenance costs

Application:

• retention tanks
• combined sewers

Technical data:

• Width: 1.0 – 10.00 m
• Flushing capacity: 200 – 2500 l/m (every 100 l/m)
• Material: stainless steel

A pump with a set of nozzles that produces a water-air mixture used as a sediment-cleaning jet for the tank.  With a rotating nozzle, the single unit has a wide flushing range. A dedicated software is used to optimise energy consumption during the flushing process. 

Application:

• retention tanks
• wastewater treatment plants
• combined sewers

3 phases of device operation:

• Aerating phase: tank is full, wastewater is aerated and sedimentation of sludge is reduced
• Mixing phase: starts at the beginning of emptying, keeps sediments and pollutants in suspension
• Cleaning phase: Cleaning phase: tank empty, removes impurities from the bottom, final flush

The AWS-Flush Sluice is installed directly on the sewer system, without interfering with the flow in the sewer, and is used for regular flushing of sensitive sections of the system. The closing of the sluice causes the water to pile up, while its sudden opening creates a powerful wave that removes sediment and debris, carrying it to less critical areas. Thanks to the customised algorithm, the device automatically cleans the sewer system, even during periods without rainfall, which increases the hydraulic efficiency of the system. 

Application:

• combined sewer systems
• sanitary sewer systems
• stormwater sewer systems

Advantages:

• easy installation in existing channels
• channel cleaning during dry weather
• automatic fault signalling
• no flushing chamber required
• automatically opens in case of power failure

The Ask-Weir overflow edge installed on the emergency overflows of the storage reservoirs allows automatic control of the wastewater level in the reservoir. In emergency situations, it ensures rapid discharge of excess sewage and reduces the risk of overflowing the reservoir. 

Advantages:

• maintains a constant water level
• no need for external power
• retention of suspended and floating elements 
• compact design
• maximum operational safety

Application:

• retention tanks
• dams
• hydropower plants
• polders

Technical data:

• Height: 0.3 – 3.0 m
• Length: 1.0 – 10.0 m
• Capacity: up to 100 m³/s
• Type of drive: float
• Material: stainless steel / composite

The Asa-Weir adjustable overflow, used in sewer systems or open sewers, allows precise regulation of water and waste water levels. It enables flow control, optimal use of the retention capacity of the tanks and the sewer system, and the generation of flushing waves. It protects against flooding and ensures safety even in the event of a power failure. The overflow has adjustable working levels. 

Application:

• retention tanks
• coastal protection / levees
• separation systems
• polders