Start-up Seed Sludge Augmented Using Microcat - UASB BioBlend
The commissioning of a new wastewater treatment system consisting of an upflow anaerobic sludge blanket reactor (UASB) can be slow and expensive. In this case the UASB is followed by an aerobic activated sludge treatment system at a brewery.The system is located in a rapidly growing part of Asia.
- Influent Flow Rate: 1400 m3/day
- Influent Chemical Oxygen Demand (COD): 5600 mg/l
- Influent Biochemical Oxygen Demand (BOD): 1900 mg/l
The objective of this program is accelerate the startup in order to keep the start up period of the UASB reactor to a minimum so as to achieve wastewater discharge limits as soon as possible. Flow through the UASB reactor is 1400 m3/day. The volume of the UASB reactor is 1059 m3.
In order to facilitate the start up of the UASB reactor, 25 m3 of anaerobic sludge at 2-3% dry matter (dm) from a nearby UASB reactor is imported. Additionally, 10 m3 of sludge from an anaerobic digester at 3 to 4 % dm from a distillery is introduced into the new UASB reactor. The imported sludge seeds are augmented with Microcat-UASB BioBlend for Anaerobic Systems according to the following application rate schedule:
- Days 1 through 10 - 3.7 lbs/day ( 1.68 kg/day)
- Days 11+ 0.33 lbs/day (0.15 kg/day), and thereafter
The Microcat-UASB is prepared by adding the required amount of product to tepid water and mixing it for a minimum of 30 minutes and then adding it to the UASB reactor
Results and Conclusions
The treatment plant achieved COD removal rates between 90 to 95% within the first month of commissioning. The customer called the performance of the Microcat - UASB quite satisfactory in accelerating the startup of the system. Even with imported sludge such startups can take several months to achieve similar COD removal results.