Features

September 2012, Vol. 24, No.9

Warming up to winter

New trickling filter design provides reliable nitrogen removal year-round

Feature 1 art.jpg Scott Dunn, Mark D. Poole, and Dan Goodwin

Trickling filter technology has a long history as a reliable form of wastewater treatment and has been used since the 1800s. This longevity can be attributed to the trickling filter’s simple design, low cost, and, most importantly, good results for biological treatment — assuming, of course, it is designed and operated properly.

For ammonia removal, trickling filters do well in warm weather, but cold temperatures lead to poorer performance. But a Pennsylvania treatment plant has uncovered a design innovation that enables nitrification even during extremely cold months. Read full article (login required) 

 

Analyzing anammox

Pilot-testing of the anaerobic ammonium oxidation process at a New York City treatment plant reveals great promise as a means for removing nitrogen from centrate

Feature 2 art.jpg Krish Ramalingam, John Fillos, Alex Rosenthal, Isaiah Shapiro, Mahsa Mehrdad, Allen Deur, and Keith W. Beckmann

Anaerobic ammonium oxidation (anammox) is a recently discovered microbiological process that converts ammonia and nitrite directly to nitrogen gas. The application of anammox in wastewater treatment results in the lowest operating cost and carbon footprint of any currently applied biological nitrogen removal (BNR) process. During the past decade, approximately 30 full-scale anammox reactors have been built and successfully operated in Europe and Asia to treat nitrogen in high-strength

wastestreams laden with ammonium, including anaerobic digester reject water, or centrate. Although a full-scale anammox process has yet to be commissioned in the United States, bench-scale and pilot studies have demonstrated its effectiveness. As a result, several full-scale U.S. anammox facilities currently are in the design phase.Read full article (login required) 

 

From short-term to long-term sustainable solutions 

Damascus, Ore., develops complex integrated water management plan 

Feature 6 art.jpg Emily Callaway, Dave Green, Mark Anderson, and Steve Gaschler
Sustainable water resources management has become a key objective for the City of Damascus, Ore. Currently rural in character, the Damascus area is expected to grow to an urban population of approximately 50,000 during the next several years. Given the increasing value of water resources throughout the region, there is a need to provide water, wastewater, reclaimed water, and stormwater services for new and existing development using an approach focused on managing all these water resources in the city. Read full article (login required) 

 

Operations Forum Features

Careful measures

Using management ratios to measure performance 

Feature 4 art.jpg Erik Grimstad and Karl Birky

Numerical ratios appear everywhere. New hybrid cars consume fuel at a rate of 19 km/L (44 mi/gal), a ratio. Olympic athletes can run 1.6 km (1 mi) in 3.75 minutes (an impressive ratio). Police officers pay close attention to how many miles per hour cars are traveling (a potentially expensive ratio). When considering loans, banks calculate applicants’ debt-to-equity ratios, a standard that compares how much money a person owes to his or her net worth.

The question becomes, What ratios should wastewater treatment plants be calculating and comparing to other treatment plants? The answer will vary with each plant’s individual goals, interests, and needs. But there exist some basics in ratio analysis that are relatively universal. Read full article (login required) 

 

A triple win for Los Angeles County Sanitation Districts 

A staff-initiated mentoring program pairs senior engineers with new hires to ease such issues as a complex work environment, knowledge transfer, and professional development 

Feature 3 art.jpg Steve Maguin, Grace R. Chan, Brian Villacorta, Tom Fang, and Darrell Hatch

Corporations, public entities, and professional organizations encourage mentorships to develop young talent, foster growth and competency, and express commitment to their staff or members. Other managers, executives, and leaders practice mentoring in preparation for retirement and succession or simply to serve and make a difference. When the mentoring model works well, all the participants in this process walk away with something new. The takeaway messages from mentoring include satisfaction through service and workforce engagement.

The Sanitation Districts of Los Angeles County (LACSD) decided to forge a program in 2007 following the recognition 2 years earlier that significant workforce issues were looming. Many of the districts’ 300 experienced engineers would be retiring in the next 10 years. At the time, a more competitive hiring environment, caused by a declining number of students in environmental engineering programs, hampered recruiting efforts. For graduates who were interested, adjusting to this new profession and work culture was somewhat challenging, especially considering LACSD’s complex work environment. Read full article (login required) 

 

Am I sampling too little or too much? 

A template guides plant operators on the right areas and ways to sample for process control 

Feature 5 art.jpg John Bratby and Stephanie Fevig

Utilities expend considerable time, resources, and operating budget on sampling and laboratory work to monitor and control the performance of diverse unit processes in wastewater treatment plants. This effort often goes beyond what is needed to demonstrate compliance with effluent discharge permits, and rightly so.

Compiled plant data resulting from sampling can be used not only for permit compliance purposes but also to make important process decisions and troubleshoot the plant when upsets occur or changes are made.

To ensure that the required data are available, operators and engineers should follow the recommended procedures to establish correct sampling practices at the plant. These sampling practices are important for both plant personnel and consultants tasked with applying the operating and laboratory data. Read full article (login required)©2012 Water Environment Federation. All rights reserved.