A decline in the efficiency of the wastewater aeration process, caused by increased production, forced a Polish vegetable processing plant to make the decision to upgrade its system. The existing aeration system did not cover the entire bottom of the tank, leading to serious issues with activated sludge decay. As a result, the overall wastewater treatment performance deteriorated, and the plant was unable to meet required discharge standards.
To address these challenges, the general contractor partnered with PRODEKO-EŁK, a part of Esmil Group, which supplied modern wastewater aeration equipment as part of the upgrade.
Modernization Goal
The primary goal of the upgrade was to improve the efficiency of the aeration process for post-production wastewater following high-pressure DAF flotation. The plan included:
- Reducing COD levels,
- Improving mixing efficiency to eliminate sludge settling issues,
- Increasing the amount of air delivered to the tank.
Challenge
No possibility to empty the aeration tank. The client specified that draining the tank was not an option, either during the installation of the new system or for future maintenance.
Solution: Submersible Aeration System Based on Esmil Fiber Tube Diffusers
To meet the client’s requirements, Esmil Group specialists proposed a modular aeration system mounted on stainless steel frames. This design enables installation without the need to empty the tank or stop the operation of the treatment plant.
The aeration system consists of 180 metres of Esmil Fiber Tube Diffusers, arranged on six independent frames that were placed into the tank using a crane.
Key Operating Parameters:
- Operating mode: continuous aeration
- Wastewater level: 6 m
- Designed blower capacity: from 800 m³/h to 2600 m³/h
The blowers are automatically controlled via a frequency inverter. A monitoring system continuously tracks the level of dissolved oxygen in the wastewater and adjusts the blower speed accordingly – either increasing or decreasing the air supply based on demand. This solution ensures optimal conditions for biological processes while enabling efficient energy management.
Upgrade Results
The implementation of an aeration system based on Esmil Fiber Tube diffusers enabled:
- Reduction of pollutant levels to meet required values
- Effective oxygenation of wastewater throughout the entire tank
- Elimination of sludge settling risks through efficient mixing.
Summary
The proposal of a modular aeration system mounted on steel frames proved to be the right solution. In line with the client’s requirements, the equipment was installed without draining the tank, avoiding both downtime at the treatment plant and additional costs associated with pumping out the wastewater.
The use of Esmil Fiber Tube Diffusers effectively addressed the issues caused by poor aeration efficiency, significantly improving the overall process performance. It also eliminated the risk of sludge settling – oxygenation is now uniform and intensive throughout the tank volume, supporting the optimal progress of biological processes.
