What are the Precautions for Commissioning the Pressurized DAF System

Solid Liquid Separator September 5, 2025 Dissolved Air Flotation

Precautions for Commissioning the Pressurized Dissolved Air Flotation (DAF) System

Pipeline and Saturation Tank Cleaning

Before introducing influent water, use compressed air or high-pressure water to repeatedly flush and clean the pipelines and saturation tank until no clogging particles or impurities remain. Only then should the air dissolving (release) device be installed.
Check the Non-Return Valve on the Air Inlet Line

A non-return valve must be installed on the air inlet pipe to prevent pressurized water from flowing back into the air compressor. Before commissioning, check that the direction of the non-return valve between the saturation tank and the compressor points toward the tank. During operation, open the valve on the compressed air line to inject air into the tank only when the compressor outlet pressure exceeds the tank pressure.
Initial Commissioning with Clean Water
Start by commissioning the pressurized dissolved air system and the air release system with clean water. Once the system is running normally, introduce wastewater into the reaction tank.
Keep the Outlet Valve Fully Open
The outlet valve of the saturation tank must remain fully open to prevent water flow obstruction at the outlet, which can cause premature bubble release, coalescence, and enlargement.
Maintain Stable Water Level in the Flotation Tank
Adjust the effluent regulating valve or adjustable weir plate to stabilize the water level in the flotation tank at 5–10 cm below the scum trough edge. Once the level is stable, regulate the influent and effluent valves to achieve the designed treatment flow.
Operate the Sludge Scraper at Proper Scum Thickness
When the accumulated scum layer reaches the appropriate thickness (5–8 cm), start the sludge scraper to remove it. At the same time, check whether sludge scraping and discharge are functioning properly and ensure that effluent water quality is not affected.