For years, many didn’t understand how biosolids came to be, how they are being used, how beneficial are they on land, and how to manage them. It is only in the last decade that people begin noticing how important biosolids is in terms of crop production and boosting nutrient-rich organic soil.
Basically, there are three ways we can utilize biosolids. It can be used as a fertilizer in replacement of chemical and commercial-grade fertilizers or it can be used to amend the soil and turn it into organic soil or it can be disposed as a simple sewage sludge.
The decision will depend on the stability of the biosolids, the degree of pathogen treatment, the extent and cost of processing, climate and land use, regulatory constraint, pollutant concentrations, local geography, and public acceptance. All of these factors will play a role in managing biosolids in the community.
In many states, the management of biosolids or sewage sludge fall into four categories: landfilled, surface disposal, incineration, and land application and other beneficial uses.
Landfill disposal is the easiest solution to manage biosolids or sewage sludge. When a landfill is properly constructed and maintained, the release of pollutants and other chemicals from biosolids is very minimal. It is also cheaper to throw biosolids in landfills as compared to other methods. Of course, the process it takes to build a landfill can be quite a headache. Not many communities allow the construction of landfills within their midst. There are also environmental and health concerns, including the possible leakage of sewage sludge into the groundwater.
This method might have been phased out in many states. It’s not exactly the most environmentally-friendly option because sewage sludge will be disposed on an area like monofills, lagoons, waste piles, surface impoundments, and dedicated disposal sites.
Incineration is the process of burning biosolids in very high temperature in an enclosed device. It does not completely get rid of the biosolids but merely reduces its volume, kills pathogens, and destroys most organic chemicals. However, you still have to manage the ash produced by the incineration. The ash contains trace elements that have been multiplied five to 10 times the original levels. Incineration is also environmentally damaging because it produces carbon dioxide.
When biosolids has been properly treated, land application is possible. The application of biosolids on land can condition the soil or fertilize crops and vegetation. It can be applied on agricultural land and forestland, disturbed land for reclamation, conservation land or recreational land, and other beneficial use sites.