Aluminum residual for water sludge, is that why it has to be landfilled
asked 4 December 2016 asked by Joe Scratch (4660 points)
I do not know where you are located but the provinces of canada as well as the united states have regulation regarding sludge landfilling. The regulation define the acceptable concentrations of many metals, the amount of sludge that can be applied to soil, the method and timing of the application. If you don't meet all of the requirements lanfilling is not possible.
Yes good point. In Canada. I've tried researching the issue further and it looks like there isn't an exact rule book for this. But one of the key criteria it to be below 0.1 mg/L for aluminum residual. But based on other values even if you are below that that might not accept it.
Sludge might be a free fertilizer that can be used when it is properly treated, but it also contains a number of heavy metals. The issue isn’t just with aluminum residuals (which can actually be removed from the final product). There are a number of potential contaminants that could affect the environment or personal health. Triclosan is in sludge, which is an antibacterial chemical in everything from toothpaste to soap to toys. This chemical is linked to immune deficiencies and birth defects. It’s been banned in Canada already, but not in the United States. Radioactive materials are found in the urine of people undergoing chemotherapy treatments, which then enters the wastewater cycle. Arsenic, lead, and mercury can remain in wastewater. Microbial contaminations can also exist in sludge, even after it has been professionally treated. This includes the potential exposure to Hepatitis A. And the fact is that no one really happens to know what one sludge delivery may contain. So that’s why sludge may have to be landfilled. It may have nitrogen and phosphorus – good stuff for growing – but the bad stuff can have a terrible impact on croplands.