Chicken Abattoir

New Build

AFGRI, a leading agricultural services and food processing company in South Africa required a new wastewater treatment plant to treat the effluent from one of their chicken abattoirs.

 A lagoon was excavated to treat a flow of 2,500 m3/day using an activated sludge process

Design parameters:

  • Lagoon dimensions: 57m X 30m X 4.5m with a slope of 1:2.5
  • Inlet BOD: 150 mg/l
  • Inlet Ammonia: 120 mg/l
  • Site elevation: 1,560m above sea level

Challenge

To supply an aeration system suited to the lagoon, with a standard aeration efficiency of more than 2.5 kgO2/kWh and to meet the required effluent quality of BOD<40mg/l and ammonia <5mg/l.

Solution

Four of Mapal’s floating aeration units were installed in the aerated lagoon to supply an oxygen transfer rate of 160 kgO2/hr (SOTR). Each unit included 40 meters of Mapal’s fine bubble diffusers. The floating units received an air flow rate of 2,800m3/hr from a positive displacement blower located next to the lagoon.

Results

The system operates at a power consumption of 60 kWh and continues to deliver high quality effluent and efficient aeration complying with the local regulations. The client ordered another Mapal system for a second site based on the success of the first installation.