While well-known as a soil amendment, biochar also benefits the wastewater remediation process. Wastewater treatment involves removing contaminants from wastewater and recycling the water back to the environment for industrial use, irrigation, and even drinking and bathing.
In this era of environmental awareness, conventional wastewater remediation is both energy-intensive and costly. Green technologies such as manufacturing biochar offer more sustainable wastewater management with energy efficiency.
Our premium biochar for wastewater remediation can help remove micropollutants in treatment plants, one of the plant’s primary functions. Because biochar is easily sourced from agricultural and solid green wastes, it is not only environmentally friendly but less expensive than other municipal water remediation methods.
How Does Biochar Benefit Municipal Wastewater Remediation?
At Wakefield BioChar’s beneficial reuse division, we turn organic waste that would otherwise be thrown out into a useful and valuable commodity.
So, what is biochar, and how can it benefit municipal wastewater remediation? Biochar is created by heating biomass at high temperatures in a low-oxygen environment, a process known as pyrolysis. At Wakefield BioChar, we produce our products from virgin wood scraps from paper and timber mills. However, biomass used in creating biochar may include:
- Animal manure
- Wood chips
- Rice hulls
- Food industry waste
Removal of organic and inorganic contaminants
Biochar water treatment effectively removes organic and inorganic contaminants from wastewater. The former include:
- Polycyclic aromatic hydrocarbons (PAHs)
Biochar removes organic contaminants due to its pore-filling hydrophobic effect. It is effective in removing dyes ending up in wastewater from the textile industry because of its high sorption rate.
Certain antibiotics, such as tetracyclines and sulfonamides, are becoming more of an environmental concern because they do not decompose readily in the natural environment. These antibiotics are not only commonly used by people but also fed to livestock in feedlots for disease prevention and weight gain. In studies, biochar demonstrated the potential to remove these antibiotics in water.
Inorganic contaminants removed by biochar include:
- Ammonium ion
Heavy metal removal
Heavy metals are among the inorganic contaminants biochar can remove from wastewater. In water, heavy metals generally come from the effluents of activities such as mining, smelting, and electronic manufacturing.
Pharmaceuticals make up an increasing percentage of the organic contaminants found in wastewater. Devastating effects on aquatic ecosystems and wildlife result. The EPA has deemed pharmaceuticals as a “contaminant of emerging concern.” Most wastewater treatment methods do not remove pharmaceuticals directly.
In one study, biochar was tested for its ability to remove seven common pharmaceuticals from synthetic urine. The drugs included the over-the-counter anti-inflammatories acetylsalicylic acid, paracetamol, ibuprofen, and naproxen. Biochar removed 90 percent of the pharmaceuticals while leaving more than 80 percent of the nitrogen and phosphorous content.
Reduction of pathogens
To date, biochar’s removal of pathogens in wastewater focuses on treating urban stormwater runoff. Stormwater treatment systems, such as conventional biofilters, are generally ineffective when it comes to pathogen removal. In addition, E. coli and other pathogens can grow in biofilters during intermittent stormwater infiltration.
Due to hydrophobic interaction, biochar can remove pathogens. During intermittent flow, biochar increases the moisture content, which limits the ability of previously attached pathogens to remobilize. The addition of biochar helps native microbes consume the nutrients that pathogens would otherwise utilize.
Enhanced nutrient removal
Wastewater contains a substantial amount of nutrients due to the sheer amount of wastewater and its concentration. Biochar enhances nutrient recycling, especially that of phosphorous, a non-renewable resource. Biochar not only recovers nutrients but is itself a source of macro-and-micro-nutrients.
Improved soil quality
Biochar is perhaps best known for improving the structure and fertility of degraded soils. After being used for wastewater remediation purposes, the waste biochar has the potential for regeneration. This waste biochar can then be used as a soil amendment to boost soil quality.
Low pH in stormwater is usually the result of mining activity, industrial runoff, leaching from landfills, or draining of wetlands or floodplains. Biochar raises soil pH.
The manufacturing of biochar reduces the amount of carbon dioxide getting into the atmosphere making it an excellent tool for combatting the greenhouse gases driving global warming and subsequent climate change. For every pound of biochar applied, about two pounds of carbon dioxide are removed.
How to Apply Biochar to Wastewater
Here’s how to use biochar when dealing with wastewater:
Mixing it directly
Mix biochar directly with sand to create a natural biofilter that can remove E. coli from stormwater. E. coli binds more effectively to biochar than it does to sand.
As noted, biochar-based filters can remove pathogens while limiting or preventing the ability of bacteria such as E. coli to grow in the biofilter during intermittent flow.
Use biochar alone or with other components for stormwater filtration. Underground infiltration basins and trenches are often constructed in coarse soils. Such soils generally do not have the ability to retain pollutants. Biochar reduces infiltration rates while adsorbing pollutants.
Use biochar hanging filters in catch basins, in filtration socks and slings, or applied directly to swale systems or stormwater storage vaults.
Learn More From Wakefield BioChar
At Wakefield BioChar, our holistic approach of connecting biochar to wastewater management creates a clear path for municipalities to make a difference in environmental stewardship.
Better Soil. Better World.