Physical water treatment (PWT) is a general term that refers to non-chemical methods of controlling or preventing fouling, especially mineral fouling or scale. PWT technologies use the laws of physics to impact water chemistries and mitigate scale without the use of chemical additives. Such technologies target lime scale, an extremely adhesive crystalline precipitate of calcium carbonate, which is responsible for the majority of scaling problems. Calcium carbonate also traps other minerals, such as magnesium, to form combined scales, just as it traps soap in residential sinks and bathtubs to form so-called "soap scum."
This article originally appeared in the 11/01/2005 issue of Environmental Protection.
Over the past few decades there has been an increased awareness of the importance of water quality. Many municipalities and industrial facilities have upgraded or installed new technologies to meet the demand for clean water. Advances in water quality science show that further improvements are needed to ensure a plentiful water supply and to protect the natural environment.
- By W. Wesley Eckenfelder, William Ney Hansard
This article originally appeared in the 10/01/2005 issue of Environmental Protection.
Despite the very best in design, there does come a time in every wastewater lagoon system when sludge must be removed.
This article originally appeared in the 09/01/2005 issue of Environmental Protection.
Ultraviolet (UV) irradiation is a proven disinfection technology that has been used for almost a century. The technology is used to disinfect drinking water (municipal and consumer), wastewater (discharge and water reuse), indoor air, swimming pools, and industrial effluents from the food and beverage industries, cooling towers, fish hatcheries, ballast water, semiconductor fabricators, and pharmaceutical manufacturers.
- By Bertrand W. Dussert, PhD
This article originally appeared in the 09/01/2005 issue of Environmental Protection.
n the July/August edition of Water & Wasterwater Products, the first appearance of this column, I referred to my first "real" job: a 1974 internship in the office of the U.S. Senator from Wisconsin who died recently at the age of 89.
This article originally appeared in the 09/01/2005 issue of Environmental Protection.
Web-based software helps predict sewer failure and overflows by monitoring flow data
This article originally appeared in the 09/01/2005 issue of Environmental Protection.
Water quality is intimately connected to quality of life. Although this fact of life has been understated for many years, water professionals have long known that clean water is an increasingly scarce and valuable commodity that cannot be taken for granted. The Clean Water Act brought about increased regulatory oversight, resulting in recent criminal charges and fines against violators, and environmental organizations are succeeding in bringing about public awareness of the need to protect water resources by encouraging businesses to include water stewardship and utilization in corporate sustainability reporting.
This article originally appeared in the 09/01/2005 issue of Environmental Protection.
There are two standards that apply to municipal water and wastewater treatment plants: NFPA 820 Standards for Fire Protection in Wastewater Treatment and Collection Facilities, 2003, and OSHA 1910.148 Appendix E: Sewer System Entry. While both standards apply, they address different facets of the treatment facility.
This article originally appeared in the 09/01/2005 issue of Environmental Protection.
The other day a person preparing to make a presentation on small aboveground storage tanks (ASTs) asked me for a "sexy spin" on fuel tanks. I wasn't sure if I should be amused or upset. Fuel tanks are designed to hold fuel. That's it.
This article originally appeared in the 07/01/2005 issue of Environmental Protection.
All roads leading to the control of greenhouse gas emissions pass through Kyoto, right? Wrong! The Kyoto Protocol is just one part of the burgeoning web of mandatory, voluntary, and market-based programs for addressing global climate change.
This article originally appeared in the 06/01/2005 issue of Environmental Protection.
Too much chlorine. That's what the residents of two Tennessee cities said about their drinking water following a recent upgrade to their water treatment plant (WTP). As part of the upgrade, granular filter media from the conventional plant were removed and immersed, hollow-fiber ultrafiltration (UF) membranes were added to the plants treatment processes.
This article originally appeared in the 05/01/2005 issue of Environmental Protection.
Unlike government bodies in the recent past, which specialized in collecting and storing data, government agencies today seek to actively use water data for improved understanding and management of environmental conditions -- for example, through modeling and projection work. For this reason, it is imperative that monitoring agencies, scientists, and researchers receive water data in a reliable, timely, and easy-to-understand manner.
This article originally appeared in the 05/01/2005 issue of Environmental Protection.
The lack of attacks launched against water treatment plants is by no means an indication that they are invincible. While treatment plants aren't typically seen as high profile targets, they are at risk of infiltration and/or sabotage. Plants, many of which are based in or near residential areas, purify water for vast regions. Destroying or disabling a single facility could devastate an entire national region for an indefinite amount of time and create a real sense of uneasiness among those forced to suffer without water for a long time to come.
This article originally appeared in the 05/01/2005 issue of Environmental Protection.
Since the late 1990s membrane bioreactor (MBR) technology has rapidly entered the wastewater treatment market. The technology is a simple combination of an activated sludge process and a membrane filtration step. The separation of activated sludge and effluent is achieved by using porous membranes that are able to remove all the suspended solids from the biologically cleaned water.
This article originally appeared in the 03/01/2005 issue of Environmental Protection.
In 1997, researchers first used newly developed contaminant analytical capabilities to detect low concentrations of the perchlorate ions in groundwaters and surface waters.<sup>1</sup> These tools helped substantiate the U.S. Environmental Protection Agency's (EPA) assertion that perchlorate is leaching into the drinking water supplies of approximately 15 million to 18 million Americans.
This article originally appeared in the 03/01/2005 issue of Environmental Protection.
When the staff at Middletown, Ohio's wastewater treatment plant decided two years ago to switch from gaseous chlorine to sodium hypochlorite for disinfection, they also wanted to find an alternative to using a pressurized liquid chemical delivery system.
This article originally appeared in the 01/01/2005 issue of Environmental Protection.
Benjamin Franklin once said, "When the well's dry, we know the worth of water." With that in mind, paper companies recognize it is not a question of whether they should treat and recycle their spent water -- the question is "How?" Some paper companies are not only finding environmentally friendly ways to take care of spent water, they are going a step further by putting the sludge from their wastewater treatment plants to beneficial use by converting it to glass aggregate, steam, and electricity. In fact, paper companies are leading the charge in using practices that reduce the consumption of resources and related emissions for themselves and their customers.
This article originally appeared in the 12/01/2004 issue of Environmental Protection.
The environment in which the water and wastewater industries operate has never been more challenging. Increasingly complex financial and environmental regulations, security concerns, and shrinking budgets are just a few of the realities keeping managers up at night. Simultaneously addressing these sometimes conflicting demands may seem overwhelming on the surface, but it doesn't have to be. Experience shows that integrating information -- both horizontally and vertically throughout an organization -- can make it easier to satisfy these competing concerns, while at the same time producing additional measurable benefits.
This article originally appeared in the 12/01/2004 issue of Environmental Protection.
Until just recently, water was viewed as a low-cost commodity. This perception has changed as communities across the United States face water supply limitations and plant managers look for ways to cut their process water treatment cost.
This article originally appeared in the 10/01/2004 issue of Environmental Protection.
While reminiscent of the many ranches that once occupied this region, the slowly turning windmill and large cisterns on the Roy Lee Walker Elementary School campus in McKinney, Texas, are not intended for decoration. They're examples of the many sustainable practices the school district has incorporated to protect the environment and teach environmental awareness through hands-on learning.
This article originally appeared in the 09/01/2004 issue of Environmental Protection.