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Biosolids as a Source of Alternate Energy

Biodrying biosolids makes it much more practical to use as an alternate fuel, by reducing the moisture content and making it much more manageable to transport and feed into a burner.

Wastewater biosolids a product that we will only see more of in our world. As we improve our wastewater processes to dump less waste into our waters, including our streams, lakes and ocean, we will generate more biosolids. Worldwide, approximately 50% is recycled for agricultural uses, and a smaller percentage is incinerated or used as an alternate fuel.

Reusing the biosolids to our soils to provide nutrients and organic matter is important for the health of our soils, however, some are concerned about some of the chemicals that we put into toilets and end up in our biosolids. Incinerating the biosolids or using them as a source of alternate fuel is also not without environmental consequence. Some are concerned about the air emissions resulting from using biosolids as a fuel.

There are a number of challenges with using biosolids as a fuel source. Firstly, its 75-80% water, which makes it expensive to transport. Secondly, biosolids are sticky and lumpy, making it difficult to feed efficiently into a burner, Thirdly, a considerable amount of the energy in the biosolids is used up in the transport and drying of the biosolids before it can be used as an alternate fuel.

We tried biodrying biosolids and made a number of observations. The ability to biodry biosolids depends on the available energy in the biosolids, which is directly correlated with the amount of processing at the waste water plant. For example, one biosolids from a small community where minimal wastewater processing occurred allowed drying of the biosolids from 77% moisture to 28% moisture in two weeks. Contrastingly, a biosolids produced from a community with more extensive processing had little available energy resulting in minimal biodrying potential!

Biodried biosolids are much easier to transport and manage, and have available energy to be used as a fuel.

The resulting dried biosolids has a calorific value similar to brown coal. It is also much more transportable and simple to feed into a burner system.

Calorific values and proximate analysis of the biosolids biodried to 28% moisture.

Additional drying of the biosolids can be achieved if we used heat recovery or heat exchange. This is done at some biodrying facilities, and is a process that can be easily added. The present drying was achieved only with the energy already present in the biosolids.



Biodrying – Stabilizing and Processing Wet Organic Waste

There is a lot of wet organic waste produced in our society, including food and food processing waste, biosolids and animal manures. Moisture contents of these materials are often 75-80% or higher. There are at least three potential challenges with these materials including:

  1. High odor potential – many of the wet organic wastes do not have a pleasant odour, or are
  2. Material handling – many of the wet organic wastes are wet and sticky, and can be challenging to manage as it neither flows nor pours very well.
  3. Transportation – many of these organic wastes have excellent nutrient value, but must be processed before beneficial reuse. Transporting 80% water is not efficient.

Drying these materials for more efficient management is not economically viable in most cases.

There is a concept called biodrying that has been used successfully to dry and stabilize wet organic waste. Biodrying uses the potential energy in the organic waste to allow the moisture to evaporate. Let’s look at one recent example from our own work.

Temperature and airflow during biodrying of wet organic waste starting at 77% moisture and ending at 26% after two weeks.

We evaporated 80% of the water contained in the wet organic waste in two weeks, with 80% of it evaporating in the first week. The other interesting observation was that the organic waste, which started out as a highly malodorous material, had almost an earthy smell after biodrying.

In these experiments, there was no energy input of any kind, other than the energy in the waste. Incoming air was provided only by the vacuum caused by the self-heating of the organic waste – there were no air blowers.

Its a fun process utilizing principles of microbiology and physics!

Environmental Management in an Age of Antibiotic Resistance

In the time before Christmas, we hope, we anticipate. We hope for peace in our world, a place where we all can flourish.  We are thankful for the ways that we could participate in making our world a better place for all of us.

We are proud to be working with our communities of Abbotsford and Mission in a small but yet a very important and global effort to reduce the threat and cost of antibiotic resistance resulting from biosolids management in three distinct ways:

  1. By ensuring that the biosolids meet strict microbial standards before they are released.
  2. By advocating that Class B biosolids having high fecal coliform should be properly treated before entering our environment.
  3. By innovating and continually looking for solutions to better manage our biosolids, through composting or other technologies.

Some of the solutions such as composting not only reduce the risk of microbial resistance, but reduce other substances of concern by up to 99%. It also reduces cost of transportation as well as odour and other social concerns normally associated with landspreading of biosolids.

Investing in good management today reduces the health care cost for our children and gives us the satisfaction of knowing that we did our small part for our community and our world.

Importance of our environment in managing antimicrobial resistance (drawing from FAO website)

Importance of our environment in managing antimicrobial resistance (drawing from FAO website)

The health care cost of antibiotic resistance, or commonly referred to as superbugs, is expected to reach $ 100 trillion annually by 2050. The World Health Organization stated that “Antimicrobial resistant-microbes are found in people, animals, food, and the environment which include our water, soil and air.” They show up in hospitals because that’s where we end up if we are sick. Its also where people are more likely to be compromised, after surgeries, or cancer treatments.

How we manage our waste, our water and our food is important. They are all interconnected with our health.

Personally, I am thankful to utilize 30 years of training and experience in microbial ecology to work towards the well being of our planet.

Regulations in British Columbia Limit Biosecurity and Waste Management Options For Poultry Producers

We encourage our local and provincial governments to consider their regulations to allow enhanced biosecurity and sustainable waste management options for the poultry industry.  The poultry industry indicates that enhanced biosecurity for poultry manure management includes:

“All manure handling must be documented. While the minimum standard is documentation of its removal, onfarm composting prior to any removal would be an enhancement. Composting must be implemented according to local environmental standards. In any case, raw manure should not be spread on fields.” (BC Poultry Association Biosecurity Committee 2006)

The poultry layer industry in British Columbia is thriving and growing. In 2012, egg sales generated $ 113 million for the egg producers, which was an increase of almost 25% during the last five years (BC Ministry of Agriculture 2012). This industry generated approximately $ 617 million in economic output, 2100 jobs and $ 25 million in taxes (Price Waterhouse Coopers 2009). Much of this production is in Abbotsford, and much of the production occurs on small properties that are not able to utilize the manure produced by the birds. None of the feed is grown on the farms. The BC Ministry of Agriculture reported production of 69 million dozen eggs in 2012 (BC Ministry of Agriculture 2012), and 65 million dozen eggs from 2.6 million birds (BC Ministry of Agriculture 2013). This translates to 36.9 million dozen eggs from 1.475 million birds (Census of Agriculture 2011) for the poultry layer industry in Abbotsford.

Given that feed input is 1.88 kg per dozen eggs (BC Ministry of Agriculture 1997), and that all the feed for poultry is imported into Abbotsford, there is an import of 69,000 tonnes of feed. With an N output as manure of 2.3 g per bird per day and a N content of 5.84%, (BC Ministry of Agriculture 1997), poultry layers in Abbotsford excrete 1238 tonnes of N in 42,406 tonnes of manure, assuming an average moisture content of 50%. Where can all this manure go?

As we consider sustainable waste management strategies for agricultural waste, and consider the biosecurity concerns for the poultry industry, we need to consider how to allow this important industry to flourish. There are currently five options for managing poultry manure in British Columbia:

  1. exporting the manure to local dairy farms – will become limited with promotion of nutrient management plans and the concern regarding animal health effects of excess potassium
  2. exporting the manure to farms in the interior – not as practical for layer manure with high moisture content and we must consider the export of potentially pathogenic and antibiotic resistant bacteria.
  3. exporting the manure for use in mushroom compost production – this is an excellent solution for poultry broiler manure, but poultry layer manure is not currently used for mushroom production
  4. composting and exporting the manure into the US – there are no legally zoned properties that have developed and adopted biosecurity measures to reduce risk of exporting diseases.
  5. composting the manure to meet Good Agricultural Practice Guidelines for use on fruit and vegetable farms in BC or elsewhere
  6. Organic fertilizer production – may involve composting
  7. Other manure processing technologies – Timmenga & Associates (2003) identified several other potential promising manure processing technologies, but as yet, none of them has come to be.

Composting the manure to allow safe and sustainable export of poultry manure meets the enhanced biosecurity protocols for the poultry industry as well as enhancing the protection of our environment and public health.

The City of Abbotsford zoning bylaw, the provincial Agricultural Waste Control Regulation and the ALC Regulations may be restricting the poultry industry’s ability to meet their enhanced biosecurity goals.

On-farm composting of poultry layer manure may require a non-farm use exclusion from the Agricultural Land Commission because the import of wood waste as a bulking agent for composting is currently not an allowed use. The addition of wood waste or other high C/N ratio materials may reduce ammonia loss during composting. This is also important in the Lower Fraser Valley because of the concerns of the high ammonia emissions from agriculture and the impact on air quality. Under the current Agricultural Waste Control Regulation (Province of British Columbia 1992), import of wood waste for composting is not an allowed use:

“20 Wood waste may only be used for (a) plant mulch, soil conditioner, ground cover, on-farm access ways, livestock bedding and areas where livestock, poultry or farmed game are confined or exercised, (b) berms for cranberry production, or (c) fuel for wood fired boilers.”

The BC Ministry of Agriculture (2014) confirmed that importing wood waste for use as a bulking agent for composting manure may require a non-farm use exclusion:

“Woodwaste is the only non agricultural waste that can be co-composted with agricultural waste and the resulting compost may be used on the farm or be sold off the farm. However, the wood waste must have been previously used on the farm for one of the allowed uses described in the Code of Agricultural Practice for Waste Management….Composting operations which fall outside the definition of composting in the Code of Agricultural Practice for Waste Management may require approval from the Agricultural Land Commission. In addition, local or regional government bylaws may require permits or applications for a composting operation to be constructed or operated on a farm. ”

The City of Abbotsford zoning bylaw states that: “The area used for processing of livestock wastes into garden compost shall not exceed 465 m2 per farm operation.”  This suggests that many poultry producers would have to request a variance to the existing Abbotsford zoning bylaw.  In addition, because the import of woodwaste to blend with the poultry litter is considered a non-farm use, the City of Abbotsford’s Consolidated Soil Removal and Deposit Bylaw 1228-2003 also applies.

In conclusion, we encourage our local and provincial government to adapt current regulations and bylaws to allow our poultry industry to flourish by meeting enhanced biosecurity measures for poultry manure management, strategies that will also have a positive benefit for environmental and human health.

BC Ministry of Agriculture. 1997. Minimizing Pollution from Poultry Manure: 1. Nitrogen. Poultry Factsheet.

BC Ministry of Agriculture. 2014. Farm Practices – Composting. Strengthening Farming – Right to Farm. Order No. 870.218-29.

BC Ministry of Agriculture. 2012. British Columbia Agri-Food Industry – Year in Review.

BC Ministry of Agriculture. 2013. Website:

BC Poultry Association Biosecurity Committee. 2006. BC Poultry Biosecurity Reference Guide.

Price Waterhouse Coopers. 2009. BC Dairy, Egg and Poultry Industries: Socio-economic impact of British Columbia’s dairy, chicken, turkey, hatching egg and table egg industries.

Province of British Columbia. 1992. Agricultural Waste Control Regulation. Includes Code of Agricultural Practice for Waste Management. B.C. Reg. 131/92.

Timmenga & Associates. (2003). Evaluation of Options for Fraser Valley Poultry Manure Utilization. Prepared for the Sustainable Poultry Farming Group.

Reducing Greenhouse Gases from Agriculture in Abbotsford

With the climate change conference in Paris this week, our country, our province and our city will be thinking about opportunities to reduce greenhouse gas emissions. We and our children will be looking for ways to feel good about making a difference and positively affect climate change.

Our community of Abbotsford is termed the City in the Country because much of our City includes agricultural land, and agriculture is important to our economy. How does our agriculture impact climate change, and is there anything we can do?

We need to keep our head in the sand, We need to pay attention to our microbes, particularly our soil microbes, because they are the ones producing the greenhouse gases. We need to understand the science in its proper context so that we can make good decisions that will mitigate climate change.

In agriculture, nitrous oxide, or laughing gas, is the greenhouse gas of greatest importance, both because of how much is produced, and because there is more that we can do to reduce it. It is produced during at least two processes where the forms of nitrogen are changed by soil microbes.

Nitrous oxide emissions to the atmosphere increased dramatically since nitrogen fertilizer was invented. In fact, 60% of the world’s nitrous oxide emission now comes from agriculture,  When we add more nitrogen to our soil than is required by the plants, we can expect more nitrous oxide emission. This is even more true when we apply manure because we are adding carbon with the nitrogen, which also changes the soil atmosphere for the microbes.  As the nitrogen surplus increases, the nitrous oxide increases all the more. We learned this 20 years ago.

Research in Europe shows that nitrous oxide emission from agriculture can be reduced by 30 to 75%, simply by balancing the nitrogen we apply to our soil with the nitrogen taken up by the plant.

In Abbotsford, of the calculated greenhouse gases coming from agriculture, two thirds of it is nitrous oxide and one third is methane.  Most of the nitrous oxide comes directly from soil after we apply manure or fertilizer, and some of it is produced indirectly from ammonia emissions from animal barns and manure storages. We learned this 20 years ago.

Nutrient management planning to optimize the nitrogen in manure and fertilizer for our crops is the simplest way to impact climate change.  This has other benefits as well, including reduced potential for air and groundwater pollution.

Another way to positively impact climate change is to balance the nitrogen that we feed to our animals with the nitrogen that they need. This reduces ammonia emission, as well as nitrous oxide emission when the manure is applied to the soil. We learned this 20 years ago as well.

You may ask, what about anaerobic digestion that captures all the methane? That is an interesting question, and guess what? We learned about that 20 years ago as well! Methane from manure storage makes up 16% of the methane produced from agriculture, and less than 5% of the greenhouse gas emission. Anaerobic digestion doesn’t reduce this emission because of leakages, and the need to import other wastes for digestion.  Germany, in spite of its thousands of anaerobic digesters, learned this several years ago.

If we want to make a positive difference for climate change,  we need to keep our head in the sand, and learn the science in its proper context.

In a circular bioeconomy, we need to recycle our nitrogen in more efficient ways to make a difference with climate change. What better time to start than now? What better place to start than right here in our own community.  Lets join together to make a positive difference for our world.

Recycling Biosolids into Agriculture – Acting Locally, Responding Globally

“Using a precautionary approach, recycling biosolids for agricultural use is an important strategy for soil health and community sustainability”.  I will unfold what this means practically in our communities. I will address the excellent questions regarding trace elements sometimes also called heavy metals, microbes, and emerging substances of concern.

“Acting Locally, Responding Globally” is a byline that states the obvious, all of us are doing this every day.  As a scientist who has worked with soil and waste for almost 30 years, I participate with others around the globe to consider how we can live more sustainability on this planet.

We need to manage our leftover food in a way that is safe for ourselves and our communities.  We in the nations who are more privileged than most in the world have the opportunity to develop, and to model sustainable management for the rest of the world. And as persons who have a shared responsibility on this planet, it is our obligation. We need to act locally, and respond globally.

A sustainable community is all about protecting and enhancing our soils. Historically, we recycled our organic matter, because we understood that it was important to return the nutrients and organic matter to the land to maintain soil health and productivity.

As our society becomes increasingly urbanized, we have separated the growing of the food from returning the unused portion back to the land to benefit the soil.  With the advent of chemicals and fertilizer, we tried to live in the illusion that the soil organic matter wasn’t really that important. Today, our world is changing again, and more of us are realizing just how important our soil and our organic matter really is. This is one of the reasons why 2015 has been designated by the United Nations to be the International Year of Soils.

There is a reason that the Soil Assocation in the UK, which promotes organic agriculture, is also considering the importance of recycling biosolids into agriculture. We will explore the global reasons for this in the next few blogs. In the meantime, there is a great documentaries that help explain the recycling of biosolids.

Water Environment Assocation of Ontario:

This blog post is the introduction of a talk that I gave at a public forum organized for the Nicola Watershed Community Round Table in Merritt on January 26, 2015. The full text, along with the accompanying references, can be accessed here: Biosolids Management Jan 26 2015 talk excerpts Oct 16

Improving our agricultural waste management in British Columbia

The proposed improvements to the Agricultural Waste Control Regulation are positive, but do not reflect the current needs of our farmers, nor our public. The BC Ministry of Environment is currently reviewing and updating the Agricultural Waste Control Regulation, and invited feedback on its 2nd Policy Intentions Paper.1 This response is based primarily on areas with where most of the farm gate receipts in British Columbia are generated, and where:

“the development of certain intensive farming practices has over time created serious agricultural pollution issues that are not encountered on the same scale elsewhere in the province.” 2

Two guiding statements used in this review include:

  1. managing our environmental and public health as a prerequisite to increase our economic viability:

Increasing importance is being placed on producing local healthy food and reducing our environmental and carbon footprint, thereby promoting the economic viability of the B.C. agriculture and food sector.3

  1. our agricultural producers need to be included in shaping our regulation and industry in light of global and local environmental and health concerns and initiatives:

“in order for producers to properly fulfill their roles as stewards and managers of agricultural lands, their awareness of environmental stewardship issues needs to be increased. Producers are a vital link in the solution making progress chain and need to be informed about alternative approaches and other interests.2

Our farmers can provide solutions that are economically viable and protect environmental and human health. We have experienced this with the Avian Flu response in British Columbia, where our farmers have worked with government agencies in developing an excellent management strategy that minimizes risk for environment and public health, and meets international requirements.

Strategies and regulation for agricultural waste management must be integrated with local and global environmental and public health concerns. These include the increasing public health concerns regarding potential pathogens and antimicrobial resistance, as well as the environmental concern regarding greenhouse gas emissions.

As farming continues to intensify to meet British Columbia’s economic goals, more food is produced on a smaller land base, resulting in more agricultural waste.  The importance of sustainable management of excess agricultural waste, already identified in 19962, is now more critical because the volumes have increased, and there are additional environmental and health concerns.

The Ministry of Environment Policy Intentions paper does not deal with provincial agencies having encouraged agricultural production but have provided few options for managing excess agricultural waste. The lack of options encourages illegally zoned waste management sites which include sites on agricultural land that do not meet environmental or land use regulations. The intentions paper also does not adequately address international food safety requirements or the increasing public health concern regarding pathogens and antimicrobial resistance.

How can we invite British Columbians into a healthy dialogue for a regulatory process that benefits our farmers, our environment and our health, and allows our agricultural industry to be world leaders in modelling economic, social and environmental sustainability?

Full response to the AWMR Intentions paper is here: John Paul Response to AWCR 2nd Intentions Paper Aug 31 2015


  1. BC Ministry of the Environment. 2015. Agricultural Waste Control Regulation Review Update
  2. Management of Agricultural Wastes in the Lower Fraser Valley Program Steering Committee. 1997. Management of Agricultural Wastes in the Lower Fraser Valley. Summary Report – A Working Document. Report 9, DOE FRAP 1996-30.
  3. C. Ministry of Agriculture. 2008. The British Columbia Agriculture Plan – Growing a Healthy Future for B.C. Families.