Growing concerns about global climate change has prompted the need to develop feasible methods to reduce the atmospheric levels of greenhouse gases (GHGs). Human activities such as combustion of carbon-based fuels, cement manufacturing, deforestation, burning of biomass, and and animal husbandry is blamed for the increase in carbon dioxide in the atmosphere.
Researchers have found that it is possible capture carbon in the soil with the use of biosolids. Biosolids are a by-product of sewage sludge that undergoes a wastewater treatment process. They contain macronutrients like nitrogen and phosphorus as well as micronutrients and trace minerals suitable for plant growth. Its carbon-rich properties adequately restores carbon deposits in the soil and lock in carbon from being released into the atmosphere in a process known as carbon sequestration.
Recycling biosolids to agricultural land completes natural nutrient cycles.
According to the research of Professor Nanthi Bolan from the University of South Australia, biosolids that are applied to farmlands for revegetation has the potential to sequester carbon. Biosolids not only improves soil chemical and biological fertility but because they contain up to 30% non-degradable carbon, it can lock up carbon in the soil for longer periods. The ability of the soil to hold carbon depends on factors such as the treatment process, the type of crops and the amount of iron and aluminum.
Professor Bolan says that Australian biosolids are particularly suitable for incorporation into agricultural soils because they are generally lower in toxic heavy metals compared to chemical fertilizers.
Norman Goh, a Ph.D student of the University of Southern Australia said that scientists theorize that when biosoilds are used in agriculture, some of the organic carbon begins to accumulate over time and when applied repeatedly over the years, it becomes stored as part of the soil. This therefore has the potential to lock-up biosolid carbon which ultimately helps fight climate change.
Goh states that “the policy and science behind carbon crediting from biosolids soil carbon sequestration is still limited. We can get there but we need a bit more scientific research and stronger environmental policies to get us over the line.”
Australia needs to look further into the importance of biosolids in mitigating climate change because for it to be effective biosolids need to be used continuously and in a much larger scale to make any significant difference.
For over 30 years, various studies from around the world have proven that biosolids do not pose any danger to human health or the environment if properly applied and managed correctly. However, only select crops can be grown on the treated soil such as cereals and grains because these plants do not come into contact with the biosolids.
The process of producing biosolids undergoes stringent rules and guidelines to ensure that toxins and pathogens are kept at acceptable levels. Regulations are also in place for the safe collection, storage, and transport of biosolids.
If you are a municipality in Ontario and in need of a biosolids management solution, please feel free to contact us on 1 (877) 479-1388.