Helical speed reducers H3 flander gearbox H3-VV-26-D

Flender/Flender Gear Units/Helical speed reducers H3

d process modelling have been detailed in Section 4.7. 5 for Zeekoegat. The same benefits realised for Zeekoegat are also applicable to JP Marais: Optimal process parameters Improved final effluent quality Ease of plant operation Assessment of existing plant capacity 5-2 5.7.6 Summary JP Marais is an old plant constructed in 1. The de sign of the activated sludge process is typical of most activated sludge processes of this era that were not designed for energy efficiency. The plant uses traditional slow single speed surface aerators which ha ve low energy transfer efficiency. In addition the aeration design is not tapered and the design auto mated aeration control system was not functional during 2 because of the breakdown of both the ad justable weir and DO sensors. Thus JP Marais has an aeration energy use intensity that is 4% high er than Zeekoegat WWTP that was designed and is controlled for energy efficiency. In terms of compliance with the DWS final effluent discharge permit requirements, the plant started performing well after the flow diversion from Welgedacht WWTP was discontinued. From September 2, final effluent complied with all the permit parameter limits. In 2, the total annual power consumption at th plant was 3,3 MWh at cost of R3.1 million. Aeration consumes the most energy at the plant ac counting for approximately 7% of the total energy usage at 2,4 MWh/yr and cost of R2.3 million. Th is is on the higher end of the values generally observed at activated sludge plants. The higher aerati on percentage use is not only due to the inefficient surface aerators but also due to the absence of sl udge handling and treatment facilities which would account for some of the consumption and reduce the percentage due to aeration. The baseline total consumption and aeration energy use intensities, which serve as benchmark for the plant, were 1.2 kWh/kgCOD treated (4 kWh/peCOD 1/yr) and 0.9 kWh/kgCOD treated (3 kWh