Effective results of ShellBond in treating Hog Lagoons

Recent research conducted at the University of North Carolina at Wilmington (UNCW), sought to evaluate the use of ShellBond as an environmental cleaning agent.  They evaluated the utility of ShellBond, derived from oyster shells, here termed “Oyster ShellBond” in remediating water with elevated levels of turbidity, the nutrients ammonium and phosphate, and phytoplankton biomass at “algae bloom” levels. They used suspensions and solutions prepared in the laboratory using distilled water, amended natural pond water, and diluted liquid from a hog lagoon. 

There are over 2300 hog lagoons in North Carolina, where the state is the number-two producer of hogs after Iowa, with hog farming a multi-billion dollar business. During the 1990s, the industry exploded, growing from 2.6 million hogs in 1988 to almost 10 million today. While hog production is an important economic engine in the state, the huge number of hogs produces a mind-boggling amount of waste that pollutes the water and air and endangers public health. 

The concern and hence the solution lies in the management of the lagoons and over the environmental impacts of Concentrated Animal Feeding Operations, particularly CAFO-based swine production, owing partly to the geographic concentration of a very large number of swine CAFOs, and partly to use of waste-lagoon spray-field waste management systems. The solution lies in dealing with the environmental impacts, including odor and air pollution, nutrient overloading of soils, runoff, and potential for liquid waste spills. Extensive efforts to identify practical alternative waste treatment systems process and collateral efforts have yielded alternatives that offer Environmentally Superior Technologies.  

The results of the UNCW study to examine the applicability of cleaning the hog lagoons, in 2008, conducted by Prof. L. Cahoon, and R. Casteel, demonstrated the following results from application of ShellBond to hog lagoon waste: 

* ShellBond basic chemical properties, likely a result of calcium hydroxide formation during the hydration step in  preparation, help degas ammonia from solutions enriched in it.  

* ShellBond had a particularly dramatic effect on suppressing phytoplankton biomass at bloom levels, driving a decline of >99% in chlorophyll a levels, well below the standard for defining an algae bloom in North Carolina (40 ug chl a L-1, NC DWQ refs). 

* ShellBond demonstrates potential for treatment of water quality impairment by turbidity, nutrient loading, and algae blooms through a combination of chemical reactions and adsorptive and/or coagulant behaviors. It was much more effective than gypsum, another amendment sometimes used in water quality remediation.