Question

What are the principles involved in removing biological nutrients from waste, and what is accomplished by doing so? Where do nitrogen and phosphate go in the process?

Short answer

Nutrient removal from waste involves biological and chemical treatment, with the aim of reducing water pollution. Nitrogen is typically converted into gaseous forms that can be released into the atmosphere through a process of nitrification and denitrification. Phosphate is removed primarily through enhanced biological phosphorus removal (EBPR) or chemical precipitation as a metal phosphate, both of which make it possible to remove phosphate via sedimentation.

Step-by-step solution

Understanding Nutrient Removal

The process of removing biological nutrients from waste involves two main principles.\n1. Biological treatment: This is where microorganisms decompose organic matter.\n2. Chemical treatment: This involves the use of chemicals to precipitate and remove nutrients.\nThe purpose of removing these biological nutrients is to reduce the levels of nitrogen and phosphorous in the water, which can otherwise contribute to water pollution in the form of harmful algal blooms.

Understanding Nitrogen Removal

The process of nitrogen removal involves converting nitrogen into gaseous forms that can be released into the atmosphere. This is often done biologically through a process called nitrification followed by denitrification.

Understanding Phosphate Removal

The removal of phosphate is primarily achieved through a process called enhanced biological phosphorus removal (EBPR). In this process, certain bacteria remove phosphate from water by converting it into a form that can be removed through sedimentation. Alternatively, phosphate can be removed chemically by precipitating it as a metal phosphate, which can also be removed through sedimentation.