Posted by Louise Rainone on June 10th, 2011 in Uncategorized

A biological treatment system coupled with specialty pumps, blowers and a smart control system provides clean water quickly.

Droughts are currently ravaging the American southwest. The earthquake in Japan deprived 1.4 million homes of access to clean water, and water-borne illnesses are the leading cause of death globally. While the availability of water should always have been a consideration, it has only recently come to the forefront of concern in the U.S.

The blossoming population, here and abroad, is putting increasing strain on both clean water sources and treatment infrastructures. Wastewater treatment plants in many U.S. cities are at or above their maximum capacity, which has led to increased pre-treatment requirements on new real estate developments, and states and districts are embroiled in legal battles over the rights to and use of clean water flows. As a people, we currently appropriate 54 percent of all accessible freshwater for our own use, and this statistic will continue to rise as populations swell.

To address upcoming water shortages, the world needs to be preemptive in its approach to solving this global issue. Alternative sources of freshwater must be found, and methods of decontamination must be built to minimize the environmental, energy and economic footprint necessary to provide clean water for the future.

Biological Systems

Fortunately, the oldest method, now technologically enhanced, is poised to revolutionize this and many other industries: the use of biological systems to perform industrial cleaning activities. Bacteria are being deployed by academia and industry to perform numerous functions, such as generating power, synthesizing drugs, sensing chemicals and cleaning pollution.

The wide-reaching benefits of using living organisms to perform such activities include low power consumption, smaller treatment units, greater functionality, minimal pollution and simpler operational requirements. This is especially true for the clean up of messes created by our industrially-based life.

While using biology for such applications may seem standard in some circles today, 40 years ago, it was considered ridiculous, as chemicals were thought to be the solution to all the problems of the world (think asbestos and CFCs). Around that time, Dr. James Bernard began his work on biological nutrient removal, which formed the foundation for many applications that now use microbes to remove contaminants from water.

Bernard looked at removing pollution from water from a natural standpoint. What if we could get nature to do the heavy lifting of removing organic compounds from water? While this concept was proven decades ago, the path to practical applications has been lengthy. Proving that bacteria can consume targeted compounds is one thing.

Finding bacteria that remove all harmful compounds within a short time is another.

This requires the careful control of both the bacteria and the environment in which they live.

A Biological System for Water Treatment

The most recent advancement in this area is a water treatment system. Built upon years of research, development, design and optimization, this system is an ideal mix of a very specific consortium of microbes and the environment in which they live. The optimization of air and influent flow and habitat allows the system to treat wastewater at an astonishing rate, while producing almost no sludge. Sludge production accounts for 50 percent of traditional wastewater treatment costs. Engineering combined with microbiology makes this system work.

The product began and matured as a decade-long scientific endeavor which lead to a proprietary consortium of naturally occurring bacteria that work together to aggressively consume all organic material in a wide range of municipal wastewater streams. Once this consortium was proven effective in early prototypes, the mission changed to the optimization of the treatment process so that it minimized treatment time and maximized the daily throughput (and, therefore, provided the lowest cost per gallon treated). This is where an innovative application of pumps, air blowers and a very smart control system came into play.

Maximized Treatment Efficiency

To maximize the treatment efficiency, two main goals arose: First, expose the wastewater to as many bacteria as possible, as fast as possible. Second, deploy the bacteria in a way that makes a biofilm that stays as large and hungry as possible. To achieve these goals within the allowable bounds, the company partnered with a technology development firm that specializes in creating breakthrough new products.

Given that the bacterial biofilm grew on fixed surfaces or media such as netting or lattices, maximizing the wastewater exposure to bacteria became a flow dynamics project. The technology firm selected high-performance, low-cost pumps to propel water through each chamber of the treatment system. The most innovative part of the process was the design of special flow directors (such as plates, waterfall-like weirs and tubes) to optimize the water flow through the latticework of the living space, maximizing the number of bacteria that the water stream contacts.

Plates deflect the water jet in different directions throughout the treatment process. Tubes increase and decrease the flow rate in certain areas, and weirs ensure that water does not exit a chamber before the required retention time and associated treatment is completed. An automated control system manages everything, including pump flow, tank levels, dissolved oxygen content (DO), bacterial growth, dosing equipment and polishing filter operation.

Bacterial biofilms are analogous to any community of living organism in many ways. Maintaining a healthy population requires an abundance of food, adequate oxygen, proper living quarters and steady state conditions. To provide these requirements, the media selected provides a proper habitat for the biofilm to grow upon. The food content is supplied by the wastewater, so the dirtier the water, the more the biofilm flourishes and consumes organic waste. Oxygen is delivered to the bacteria through the application of high performance blowers and cutting edge membranes that diffuse readily from the bubbles generated, which is easily consumed by the bacteria.

The result of these efforts is a system that provides 99 percent reductions in the organic constituents of municipal wastewater for a fraction of the cost, footprint and operator requirements that are typical of analogous systems. All of this is made possible by the innovative application of relatively low-tech equipment and naturally occurring bacteria.

Pumps & Systems, June 2011

Mike Rainone is the president of AWS and vice president of Product Concept Development, Inc. (PCD), which is an innovation, science and engineering think tank on a 65-acre campus north of Palestine, Texas. AWS is a partnership between Sam Houston State University which invented the biological consortia for the Water Phoenix and PCD which was responsible for the engineering and commercialization. AWS is the developer of the Water Phoenix, which was the second place winner of the Pumps & Systems 2010 Product Innovation of the Year Award and 2010 Wall Street Journal Technology Innovation Award, first runner up in the environmental category.