Municipal Bio Ring

Aeration upgrade and inlet flow increase

Netiv HaLamed Heh WWTP is an activated sludge plant for secondary treatment. The WWTP includes a stone trap, 6mm bar screen, and a secondary Bio-Ring reactor. The WWTP serves the local community and nearby villages, and is expected to considerably expand in 2024. The existing aeration system included malfunctioning Helix-Jet aerators attached to the bottom of the reactor, and three air blowers providing 700 m3/second each, two working at a time, and one as backup. The effluent from the WWTP flows into an adjacent basin, with a capacity of 120K m3, and which is used for agricultural irrigation.


To increase the inflow of the existing WWTP from 650 m3/day to 1,060 m3/day, until the new WWTP is ready. To provide a quick upgrade of the aeration system without stopping the reactor activity. Stopping the reactor would cause the flow of untreated wastewater into the river channel, causing irreversible damage to nearby plant and wildlife, endangering ground water, and causing odor problems for the surrounding population.


Installation of Mapal’s retrievable Fine Bubble aeration units as quickly as possible, in order to avoid delays in connecting the nearby villages, and expansion of the WWTP. Three Mapal aeration units arrived onsite ready for installation. Installation was completed in one day. Two aeration units were installed in each one of the two aeration cells, and one in the sludge cell, Sludge Bacterial Seeding was conducted, and the reactor was refilled.


Following the upgrade of the plant with Mapal’s aeration units, the aeration was much more efficient, compared to the old system. Therefore, the operators could use a single blower during most of the day, replacing the two that operated constantly with the previous system, thus saving in energy expenditure, and reducing the wear and tear on the existing blowers. Several days after installation, the plant operators detected a considerable improvement in the effluent quality.