Chesapeake Bay – Current Situation
The Chesapeake Bay is in a deplorable state. The waters of the 64,000 square-mile watershed, which covers parts of New York, Pennsylvania, Virginia, West Virginia, Delaware, Maryland and Washington DC, have been deteriorating for decades due to water and air pollution.
One of the most pronounced pollution problems is the amount of nutrients, such as nitrogen and phosphorous, found in the daily flow of water entering the Bay. Industrial and agricultural wastewater runoff is the main culprit of this nutrient loading, which has caused environmental chaos. Despite increasingly strict Environmental Protection Agency (EPA) regulations and despite local cleanup efforts, the Bay’s condition has not improved much.
Total Maximum Daily Load
On December 31, the EPA issued a Total Maximum Daily Load (TMDL) program for the Bay to combat the problem. The TMDL is a regulatory tool by which the total amount of pollutants that can be allowed daily into the watershed is calculated so that the Bay meets water quality standards. In order for the Bay to meet TMDL goals, limits are placed on nutrient and sediment runoff from point sources (factories, animal feed facilities, etc.) and non-point sources (farms, forests, etc.). The two main nutrient targets for reduction under the TMDL are phosphorous and nitrogen.
Nutrient Credit Trading
As the Chesapeake Bay TMDL restrictions take effect, Pennsylvania has instituted a nutrient credit trading program, which is a market-based approach that offers economic incentives for point and non-point sources to reduce their nitrogen and phosphorous pollutants beyond the amount allotted for EPA compliancy. Those plants and farms that are already compliant can receive and trade nutrient credits if they exceed their legal obligation, and these commoditized credits can be traded with other plants. Other states such as Virginia are slated to institute a similar program in the coming year.
In addition to encouraging factories and farms to reduce their pollutants, the program has also hastened a new market for wastewater treatment technology developers, who as third-party “developers” are eligible to benefit from these credits as well. Relatively inexpensive wastewater treatment systems can be purchased by facilities to reduce the amount nitrogen and phosphorous in their runoff and become EPA compliant. For already-compliant factories and farms, developers could design, own and operate their systems at no cost to the facility, through an innovative financing approach that allows the resulting nutrient credits to be shared. This sort of arrangement would create an even greater payback for participating facilities.
Technological Solutions to Nutrient Reduction
Many larger facilities have already installed anaerobic digesters, which generate electricity and reduce the quantity of sludges from wastewater. Anaerobic digesters use microorganisms to break down organic material in waste, converting much of it to energy. However, during the process of digestion, amino acids are broken down and form ammonia. This nitrogen-rich ammonia by-product is then expelled from the digester, forcing the plant or farm to find a way of disposing it.
A Two-For One Solution – Reducing Ammonia and Creating Fertilizer
One of the most promising water treatment technologies to remove this excess nitrogen-laden ammonia is vacuum-based flash distillation, which separates the clean water from the pollutants in a controlled atmosphere chamber. This technology can be used to effectively remove 90% of the ammonia in these streams. The ammonia is removed and therefore does not have to be treated, and the overall nitrogen load of the facility is reduced by 30-40%. The process is quick and the installation is low impact, thus reducing costs substantially when compared to other nutrient solutions. The ammonia is not only removed, but is recovered and recycled as ammonium sulfate, which can then be sold as a commercial-grade fertilizer.
This type of solution, coupled with incentives available through nutrient credit trading, can actually make the process of reducing nutrient runoff a profitable endeavor. Pennsylvania may be well on its way to meeting and exceeding its pollution reduction goals. If the trend continues throughout the Chesapeake Bay states, there might be hope for the watershed.
David Delasanta is Executive Vice-President at ThermoEnergy.
David has 35 years experience in environmental engineering, construction and capital equipment industries along with marketing and operational experience including Shaw Group, IT, OHM, Metcalf &; Eddy and ICF Kaiser. In addition to his business experience, he has a strong science background with a BS in Physics an MA in Engineering and an MBA.