WE&T Magazine

WET_cover1_October13-90Water Environment & Technology (WE&T) is the premier magazine for the water quality field. WE&T provides information on what professionals demand: cutting-edge technologies, innovative solutions, operations and maintenance, regulatory and legislative impacts, and professional development.

 


October 2013, Vol. 25, No.10

Featured Articles

Gritty information

feature 1 art As any wastewater treatment professional will attest, grit can wreak havoc at a treatment facility. Yet rarely is the nature of grit quantified or understood before upgrade projects or new system designs are undertaken. Most process upgrades require extensive site-specific wastewater data (such as total suspended solids and biochemical oxygen demand), but the first step in the treatment train often is designed without taking these into account. Yet poor grit removal, handling, and processing equipment selection and performance can have significant effects on downstream unit processes. Read more  

 

Shaking the sand out

feature 2 art

Grit-removal systems often are part of the first generation of unit processes at water resource recovery facilities (WRRFs). Some of these facilities are still in use, but many have gone through upgrades and are approaching 20 to 25 years in age. Because of the abrasiveness of grit, the operations and maintenance costs for these systems can be high. 

However, due to more-stringent effluent permit limits, many WRRFs are considering other advanced treatment processes, such as biological nutrient removal, membrane bioreactors, or other upgrades that can be adversely affected by the carryover and accumulation of grit. 

Thus, there is a greater need for grit systems to achieve higher removal efficiencies, either through retrofits or outright replacement. Retrofits and additions often can face several challenges, including limited space for construction of new processes, difficulty in maintaining existing grit removal during construction, phasing of tie-ins, and hydraulic limitations. Read more
  

 

News

All shook up

news Scientists link deep-well injecting, water extraction, and earthquakes  Read more

Coming in the next issue:
WE&T small

Re-energizing the discussion

Energy and resource recovery might be the catch phrase of the moment, but there’s a good reason: Its importance becomes clear each month when the electric bill arrives. Additionally, energy and resource recovery has elements of conserving, protecting, and providing environmental services, so it is thematically in line with water and sanitation services. 

The November issue examines several different aspects of energy and resource recovery. The article, “Membrane bioreactors are not energy hogs,” evens the playing field between membrane bioreactors and conventional activated sludge for municipal wastewater treatment. By taking into account newer membrane technologies and more stringent permit limits, the energy difference between the two technologies shrinks considerably. 

Also on the topic of leveraging technology, “Harnessing big data for energy and asset management,” explains how using data science can improve energy efficiency and recovery. Information about what’s happening in a process or facility is good; organizing that information into actionable knowledge is better. 

Moving further toward recovery, “A smooth blend” details how a utility improved its operations and boosted its methane gas production by adding excess fats, oils, and grease into its digesters. Minor improvements, simple standard operating procedures, and meaningful operational data led to energy production without an increase in staff. 

Focusing on what’s next once the energy is produced, “Spreading the wealth” tells how a California utility set up the agreements and deals to sell surplus renewable energy. This type of sales requires such things as renewable-generator certifications, registrations, and coordination with various regulatory authorities. 

  

Also in this issue  

Creative innovations in sewer-flow monitoring. A Department of Watershed Management division in Atlanta invents a “sewer boat” to monitor flows and bypass obstacles. 

Bienvenidos to the green frontier. The world’s largest algae and wastewater project in Spain is showing positive results. 

The incredible growing ‘fatberg.’ Despite public education campaigns, London continues to battle grease and wet wipes clogging the city’s sewers. 

Analytical instrumentation set for growth. Automated instruments can help streamline plant operations and save on labor costs, but skilled operators still will be needed.