Sustainability Archive » Improved Effluent

Successful Procurement, Design, Construction, and Operation of Five Washington State Parks MBR Facilities

justin — Fri, 20 May 2011 16:24:05 +0000

As part of an ongoing initiative to decrease pollution in Puget Sound, Washington State Parks and
Recreation Commission (WSPRC) identified for replacement lower performing wastewater
treatment systems at five parks. In the interest of producing high quality effluent, particularly with
respect to nitrogen, while minimizing footprint on historic property and maximizing remote
operations potential, WSPRC decided on membrane bioreactor (MBR) technology to replace
existing systems. WSPRC selected a consulting firm to draft a procurement document which
standardized MBR systems across all parks which resulted in an Invitation for Bids (IFB) to select
a single MBR supplier. Flow and load capacity requirements for each park were not developed,
rather, only two MBR system sizes were defined, and representative influent criteria were applied.
This paper provides a brief overview of the procurement process, identifies successes and
challenges associated with this process, and assesses the performance of one MBR at Ft. Flagler
State Park.

A Small Community’s Goal of Improving Effluent Quality, Reducing Energy Costs and Managing Their Water Resources

justin — Fri, 20 May 2011 16:24:04 +0000

Recent societal pressures to reduce the costs associated with energy consumption and the related
greenhouse gas emissions have created a driver that is an inconsistent with the traditional goals
of water quality and environmental protection. The conflict between these goals is particularly
compelling for wastewater treatment facilities (WWTFs), as more stringent effluent requirements
are being promulgated. By and large, it can be said that the greater the required level of treatment
– the greater the energy demand. In addition, both influent concentrations and the type of
biological treatment processes used to meet the regulatory requirements play a considerable role
of the factors that must be considered. In most cases, many facilities over aerate, with no regard
to how much air is required for the process in order to obtain adequate margin of safety against
permit exceedances. The result is that the actual discharge concentrations of these constituents
are well below the permitted discharge concentration, while a significant amount of energy is
wasted in accomplishing this.
Another concern facing utilities are diminishing freshwater supplies, impacts from climate
change, population growth, and more stringent effluent disposal and water quality limitations, all
of which have all placed greater demands on the development of reclaimed water facilities to
supplement the use of this resource in lieu of potable water. Not only can the use of reclaimed
water help conserve potable water by replacing potable water for certain non-potable water uses,
it can also help recharge groundwater supplies. As a result, utilities are finding synergistic
solutions to water supply, wastewater treatment and water resources management issues.
Therefore, the adequacy and protection of our water supplies will be one of the more challenging
issues that utilities will face in the 21st century.

Process Optimization Saves Money and Unlocks Capacity

justin — Fri, 27 Aug 2010 19:49:33 +0000

The business novel The Goal was used as guidance for the optimization/continuous improvement work at the Metropolitan Sewer District of Greater Cincinnati (MSD) and greater Denver’s Metro Wastewater Reclamation District (MWRD). The work at both utilities has been successful. Increased capacity and better and more stable performance has been realized at MSD’s Mill Creek Wastewater Treatment Plant while decreasing operating expenses; better and more stable performance has been realized at MWRD’s Robert W. Hite Treatment Facility. Source: WEFTEC 2008 Proceedings

Application of Ozone and Biological Media Filtration for Reclaimed Water

justin — Tue, 06 Jul 2010 18:29:33 +0000

Use of ozone followed by biological media filtration has been shown in this comprehensive pilot and demonstration scale test to enhance secondary effluent for reclamation purposes. Some enhancements are desirable simply because of better public acceptance, including significant color reduction, and micro-contaminant reduction. However other enhancements like turbidity removal, additional disinfection and ammonia reduction improve effluent from a compliance perspective. Other technologies were trialed including membrane ultrafiltration and reverse osmosis. The ozone BMF treatment platform also improved downstream membrane filtration processes by significantly increasing stable filtration flux and extending “clean-in-place” intervals. The technology increased 5%ile UV transmissivity values from 34% to almost 60%, resulting in significant cost savings in UV disinfection equipment requirements. Lastly, preliminary results indicate ozone increases average BMF solids removal capacity by 46%. “This process delivers the best value for money now and into the future, as a platform for providing flexibility to further enhance recycled water treatment, as needed” (Melbourne Water, July 2009). Source: WEFTEC 2009 Proceedings