Nutrient pollution is one of our most widespread, costly and challenging environmental problems, according to the United States Environmental Protection Agency.  Nutrients such as nitrogen and phosphorus are essential for the growth of all living organisms.  However, excessive amounts of nutrients released to the environment by human activities can harm ecosystems and impact human health.

Some of EOSi’s MicroC® products are able to remove nitrogen through a traditional denitrification process as well as remove phosphorus through a process called enhanced biological phosphorus removal (EBPR).  As regulatory and permitting requirements continue to reduce allowable nutrient discharges, EOSi has been helping more and more customers develop and implement nutrient compliance strategies.    

The Problem

In surface waters, nitrogen and phosphorus can contribute to excessive growth of algae called algal “blooms” that can sicken or kill wildlife and harm aquatic habitats.  Algal blooms consume the dissolved oxygen in the water, leaving little or no oxygen for fish and other aquatic organisms.  Algal blooms can harm aquatic plants by blocking the sunlight they need to grow.  Some algal blooms produce toxins and encourage bacterial growths that can sicken people who swim in or drink the water, or who eat tainted fish or shellfish.  Phosphorus is more commonly the key limiting nutrient of freshwater systems.  As a result many wastewater treatment plants discharging to fresh water systems such as lakes, ponds and rivers have phosphorus discharge limits.

Phosphorus exists in many forms and are generally classified as either soluble or particulate forms of phosphorus.  Orthophosphate is a soluble form of phosphorus that is readily available to algae and aquatic plants.  Phosphates are found naturally found in soils, animals and plants. Other sources of phosphates in the environment include fertilizers, soil erosion and runoff from mining and agricultural activities, cleaners and detergents, animal wastes, and sewage and septic systems.

How EOSi can help

Wastewater treatment plants are increasingly required by state and federal regulatory agencies to reduce the amount of nitrogen and phosphorus discharged into the environment, particularly in sensitive watersheds.  EOSi offers services that help customers develop, implement and update their compliance strategy for these nutrients.  EOSi’s MicroC® products are uniquely suited for use in biological processes that remove nitrogen and phosphorus from wastewater.  

MicroC® serves a similar purpose in enhanced biological phosphorus removal (EBPR).  EBPR uses a series of anaerobic, anoxic and aerobic reactors designed to encourage the growth of phosphorus accumulating organisms (PAOs).  In response to these changing environments, the organisms store phosphorus intracellularly as large polyphosphate molecules.  The phosphorus is removed from the wastewater system as part of the waste biological sludge.  A supplemental carbon source such as MicroC® is added to the anaerobic reactors to provide the PAOs with a readily-available food supply that is necessary to facilitate the EBPR process.  

EBPR is gaining in popularity as it is viewed as a more sustainable method of removing phosphorus compared to chemical phosphorus removal which requires metals such as iron and aluminum that bind with the phosphorus.