Golden West Jetox

Jetox

Aquabio Ltd - Aeration Comparison

Jet Aeration is particularly suited to aeration of high strength industrial wastestreams, applications with large incoming load fluctuations, aerobic sludge conditioning/digestion processes and single tank processes requiring sequential aerobic/anoxic treatment or batch operation.

Aeration Comparison Table

The following table provides a comparison of jet aeration against other typical aeration techniques.

Type of Aeration System Mixing Capability Process Characteristics Reliability & Maintenance Installation and Capital Cost
Jet Aeration Extremely good, and can be designed for any tank geometry including deep tanks up to 15m Top Water Level. Air (i.e. oxygen) supply can be regulated independently of the sidestream pump mixing - for N/DN and other aerobic/ anaerobic sequential processes. Energy use can be 'tailored' to incoming load and dissolved oxygen. Distinctively high alpha characteristics (>0.9 for most strong industrial wastestreams), which significantly reduces both energy use and air flow to the reactor. Low aerosols. Low 'footprint', deep tank capability. Total control of dissolved O2 to incoming loads. Mixing is retained even in periods of low O2 demand. Robust manifold design and tank internals, ensures low maintenance and consistent long term performance. Standard design which incorporates the appropriate materials of construction for process requirements (e.g. Stainless Steels, GRP and/or coated components). Low with standard manifolds which are prefabricated in sections for ease of installation. Simple and rapid installation procedures. Dry pump installation offers reduced internal lifting gear and gives 100% external to tank access at ground level for routine maintenance.
Fine Bubble (FBDA) - Ceramic Must distribute diffusers over all of the tank base to achieve uniform mixing. Mixing is only achieved when air is available, therefore air must still be provided even during periods of low residual dissolved oxygen. 'Dead spots' can arise.

Alpha of 0.3 to 0.6 in most high strength industrial wastewaters. Leads to higher air flows and lower actual aerator efficiencies. Performance drops with increasing air flow per diffuser. Higher air blower pressures required. Increased 'off-gas' for industrial applications.

 Characteristic scaling and bio-fouling of diffuser pores, especially after long term operation or 'stop/start' sequences. Blower efficiencies reduce with fouling, with deterioration performance over time. Lower design life for some component materials. Significant number of individual diffuser pods and intricate internal pipework for total floor coverage means higher installation costs and longer programming. Critical tank base construction levels.
Fine Bubble (FBDA) - Membrane Generally as FBDA - Ceramic aeration.

Generally as FBDA - Ceramic aeration with typical alpha of 0.5 to 0.7 in most high strength industrial wastewaters.

 Generally as FBDA - Ceramic aeration with care required for membrane selection in industrial applications. Generally as FBDA - Ceramic aeration.
Coarse Bubble CBDA) Generally as FBDA - Ceramic and membrane. Generally as FBDA - Ceramic and membrane with typical alpha of 0.6 to 0.7 in most high strength industrial wastewaters.

Generally as FBDA - Ceramic and membrane aeration, although fouling and scaling not as common. Vibration on delicate fittings can be a problem.

 Generally as FBDA - Ceramic and membrane, although levelling of tank base not as critical.
High / Low Speed Surface Turbines Mixing generally very good, but effective operation limited to liquid depths of 2m to 6m due to surface operation and 'dead spots' at lower liquid levels. As with FBDA/CBDA systems, units must operate for both oxygen transfer and mixing requirements.

Dead spots arise when units are 'off-line' and energy inefficiencies can occur during constant operation (for mixing) during periods of low plant loading. High levels of off-gas, aerosols, VOC's, limited mixing options (radial only) and generally noisy Cooling through evaporation due to high surface agitation may be detrimental to process.

 Access difficult and/or inconvenient, with backward guying or pontoon system required for maintenance. Heavy components, all located in tanks. Expensive design requirement for infrastructure.