Biological treatment removes dissolved organic hydrocarbons from water. Flootech’s sophisticated, compact Floobed® Moving Bed Biofilm Reactor (MBBR) uses special, freely moving biofilm carriers, which suit high capacity operations, are particularly tolerant of variations in feed flow rate and quality, and give consistently high quality results.
Most of the microbes cultivated for purification grow attached as a film on the surface of the Floobed® MBBR’s carrier elements. Our design avoids the blocking problems that are a traditional hazard of attached microbiological growth processes. A specially designed bottom aeration system mixes the carrier elements amongst the treated water efficiently. The biomass that remains when water flows out of the bioreactor is separated by secondary clarification or micro flotation.
Having a limited footprint and high specific efficiency, our Floobed® MBBR carrier can be introduced to existing active sludge processes to meet higher capacity or more stringent quality requirements when required.
The FlooBed® MBBR process can be built to have one or several stages in series or in parallel. Excess sludge is removed from the carriers continuously by intensive mixing and abrasion. Microflotation is typically used for subsequent separation, or sedimentation, if applicable. Part of the sludge is recycled back to the FlooBed® system, and the rest is further dewatered.
Advantages of the FlooBed® MBBR:
• A FlooBed® carrier is easy to operate because it is very tolerant to peaks of organic load and variations in flow rate. It tolerates temperature variations and toxins in the feed water.
• The reactor volume needed for a FlooBed® system is considerably smaller compared to activated sludge plants. Space requirement is typically 10-40% of conventional solutions.
The FlooBed® carrier has an open structure, which facilitates a high amount of biomass and improves mass transfer efficiency. The durable structure of the carriers makes them tolerant to mechanical abrasion, resulting in low maintenance costs.
The filling ratio of carriers can be adjusted on a case by- case basis. In practice, this means the process is designed to be very flexible. Filling can be changed according to flow and load, and the FlooBed® carrier can be also built into an existing basin.
In fixed-film reactors, clogging caused by excess sludge can be a problem. The FlooBed® system minimizes this by creating turbulence that churns the water through the carriers, thus no backwashing is needed.
Design Parameters:
• Retention time typically from 1 to 4 hours.
• Organic load range 2–20 kg BOD/m3d.
• Biomass concentration in the reactor 6-12 kg/m3.
• On average 70–80% of microbes attach on the carriers.
• Low sludge circulation, 0–15% of the in-feed flow.
• Efficient aeration.
• Wide range of operating temperatures.
• Carrier filling ratio 20–60% of biomass and improves mass transfer efficiency.
The FlooBed® solution has been selected for several applications, such as effluents from process industries, landfill leachate and municipal wastewaters. In the pulp and paper industry, FlooBed® has been built into the mill area for pretreatment of existing activated sludge plants and for new mills with high requirements.
