Project Type: Municipal Wastewater Treatment - Primary Treatment Upgrade
Completion Date: April 2015
5,110 m3/day (1.35 MGD)
Effluent Total Phosphorus:
TSS: 50% Removal
BOD: 30% Removal
Project Background & Challenges
A variety of factors can cause engineers to rethink capacity expansion when it comes to getting more out of your wastewater treatment plant (WWTP). These can include anything from physical footprint and costs, all the way to the level of treatment desired and power demands for operations. On a very basic level, the simple matter of real estate can make or break the feasibility of a wastewater solution that is both effective and economical.
Located approximately 50 miles (80 kms) east of Chicago, the existing WWTP of a small Indiana town served approximately 1,000 residential customers in addition to commercial developments with a Return Activated Sludge (RAS) treatment plant designed to accommodate 0.35 MGD.
Due to upcoming changes in water quality regulations, the wastewater treatment plant (WWTP) was looking to reduce Total Suspended Solids (TSS) by 50% and Biochemical Oxygen Demand (BOD) by 30%. However, in order to meet these objectives, they faced challenges in terms of both space and budget.
The Nexom Answer
Based on it’s proximity to major routes, this small town very much reflects the “Crossroads of America” story from the turn of the previous century. It was here that engineers ultimately turned to EcoBELT™, a rotating belt filter that provided the WWTP with small-footprint primary treatment.
Engineers around the world have found the EcoBELT to be an efficient and economical solution to a variety of wastewater challenges due to its flexibility to be arranged in multiple configurations. In new plants, the EcoBELT replaces conventional primary clarification. In existing plants, these filters are integrated to expand primary clarification, as well as relieve solids and BOD loading to the secondary system. By removing this loading from the front end, the performance of secondary and tertiary processes are improved significantly.
Engineers were able to maximize the use of existing infrastructure while expanding plant capacities by installing the EcoBELT and subsequently reallocating the capacity of conventional clarifiers to the secondary system. In addition to the flexibility and ancillary plant benefits, the EcoBELT is less than one-fifth of the lifecycle cost of conventional treatment technologies.
The EcoBELT is a fully-automated, with customizable degreasing cycles to flush fats, oils and greases that accumulate over time. The EcoBELT’s reliable solids dewatering capability also means loading isn’t just diverted, it falls into a dumpster to be disposed of through landfilling.
Upgraded System Performance
Having placed the order in late 2014, the two EcoBELT units were built in Idaho, with delivery and installation at the site completed in March 2015.
Since installation, the system has successfully cut the levels of BOD and TSS flowing to subsequent processes to a fraction of the influent. During the performance test in 2014, the EcoBELT process removed on average nearly 40% of influent BOD and more than 66% of influent TSS, far outpacing the removal rate objectives set at the project’s outset.
Subsequently, the EcoBELT’s performance has stayed strong. During a three-month period in 2018 where testing was performed on the primary effluent, cBOD5 removal rates averaged 50% and TSS removal rates averaged 82%.