January 29, 2013 Biosolids

Sustainable management has made many industries – both big and small- learn one key lesson. The key to being sustainable- both economically and environmentally- is to minimize material waste while maximizing the useful life of the same material.

In the growing interests of waste diversion, wastewater treatment plants across the globe are faced with the challenge of sustainably managing their plant’s residual biosolids and identifying key value streams to which they can better use their products.

Meanwhile governments across the world are incentivizing and calling for the need to switch to renewable energy sources driven by higher-than-ever global energy demands coupled with concerns around climate change and volatility in the fossil fuel market.

Some municipalities and private companies are considering options to use biosolids as a fuel to produce electricity. This option has been encouraged by the Government of Ontario’s Green Energy Act to develop new, renewable sources of electricity generation. Sewage biosolids are defined as “biomass” under Ontario’s Electricity Act and is permitted for use in anaerobic digestion and thermal treatment facilities under the Environmental Protection Act. Such formal recognition of biosolids within government policies and frameworks offers promising certainty of the potential biosolids has within any future renewable energy programs.

Anaerobic digestion is commonly used to stabilize sewage sludge – during which biogas is produced and can be collected and combusted to produce electricity and/or heat or cleaned and used as a natural gas replacement.

Biosolids contain untapped energy (latent) that can be harnessed through conversion processes using technologies such as pyrolysis, gasification, thermaloxidation, etc.

The Lystek Process is an innovative patented, award-winning biosolids treatment and processing technology. Recycling of Lystek processed biosolids to anaerobic digesters enhances biogas production by 25%, or more, while reducing both the amount of biosolids waste and the costs associated with its disposal off-site. Lystek’s product is a readily available nutrient feedstock that helps fuel the microbial processes during anaerobic digestion.

The benefits of turning biosolids into energy include turning green waste to energy, decreasing GHG emissions by “greening” the energy, and utilizing local and sustainable supplies while reducing the emissions and costs associated with trucking and disposing of biosolids waste.

For wastewater plants that face stringent regulatory environments around composting or land application of biosolids- the opportunities surrounding biosolids-to-energy helps provide supplementary or alternative value propositions for their residual wastes. Meanwhile governments and society can capitalize on progressing towards a more renewable and energy-independent future. Interestingly enough the biosolids-to-energy pathway will not only help municipalities and wastewater treatment plants reduce their own personal carbon footprints- it could also help other industries follow suit via energy-switching.