How to Put Fertilizing Residual Materials and Biosolids to Beneficial Use

One of the objectives of the Quebec Residual Materials Management Policy is to ban the landfilling of organic matter and its incineration without significant energy recovery.

Municipal sludge and the contents of brown bins are among the materials covered by this policy.

Year in, year out, just under one and a half million tonnes of residual materials are diverted from landfill and incineration in Quebec through the beneficial use of fertilizing residual materials.

In this article, we mainly discuss fertilizing residual materials (FRMs) produced by industrial processes and by municipal wastewater treatment plants.

What is ultimate waste?

Ultimate waste is residual material left at the end of the recovery, recycling and sorting cycle. It cannot be reused, recycled or composted; in short, it has no further beneficial use. It also can no longer be treated to reduce its polluting or hazardous nature. It can only be destroyed or disposed of in an engineered landfill.

Wastewater sludge and other industrial residues are far from ultimate waste. They are, in fact, fertilizing residual materials.

What is a fertilizing residual material?

Fertilizing residual materials (FRMs) are industrial or municipal residues intended to maintain or improve plant nutrition and the biological properties of soils. They are rich in organic matter and nutrients and are generally used as fertilizers.

Manure is not considered a fertilizing residual material.

Fertilizing residual materials can come from:

• Wastewater treatment plant sludge
• Organic residues from the forest industry
• Pulp and paper residues
• Industrial ash
• Cement kiln dust
• Deinking residues
• Anaerobic digestates
• Paper mill biosolids
• Wood residues
• Municipal compost

However, before these industrial and municipal residues are spread on fields, it must be ensured that they meet certain quality criteria.

Quality control of fertilizing residual materials

A complete characterization of the residual materials must be carried out to confirm that they comply with current environmental and agronomic standards.

Samples of the residual material are collected following the DR-12-MRF-02 protocol specific to FRMs, as described in the Environmental Sampling Accreditation Program (PAÉE) of Quebec’s Ministère de l’Environnement, de la Lutte contre les changements climatiques, de la Faune et des Parcs (MELCCFP).

C-P-O-E classification

Samples are categorized according to the C-P-O-E classification:

• Chemical contaminant content (C)
• Pathogen content (P)
• Odours (O)
• Foreign matter (E)

The samples collected must meet the chemical (C), microbiological (P) and odour (O) requirements, as well as the requirements for foreign matter (E).

Contamination of FRMs and biosolids

Residual materials must not be contaminated with:

• Varnished, painted, stained or treated wood
• Engineered wood
• Wood from oriented strand board
• Plywood
• Particleboard
• Invasive alien species

FRM quality control must be carried out by a firm accredited for sampling under the program of the Centre d’expertise en analyse environnementale du Québec (CEAEQ).

Certification of FRMs and biosolids

In addition, the Bureau de normalisation du Québec (BNQ) offers three standards to ensure the quality of FRMs:

• The standard on composts (BNQ 0413-200)
• The standard on alkaline or dried municipal biosolids (BNQ 0413-400)
• The standard on calcium and magnesium amendments (BNQ 0419-090)

In some cases, FRM producers can have their residues certified by the BNQ, which allows farmers to spread them without having to obtain authorization from the MELCCFP.

Benefits of the beneficial use of municipal biosolids and other fertilizing residual materials

The controlled land application of sludge is safe, and this practice offers several advantages:

• Adds organic matter and nutrients to soils
• Low cost for municipalities or industries and for farmers
• Reduced greenhouse gas emissions

There are nonetheless some disadvantages:

• Odours
• Risk of soil compaction during spreading
• Strict regulatory and administrative controls

The beneficial use of FRMs through land application avoids the greenhouse gas emissions associated with their disposal by incineration. Modelling has confirmed that the land application of treated sludge (biosolids) is carbon neutral.

Consult Avizo Experts-Conseils’ residual materials specialists

In 2005, Avizo Experts-Conseils became the very first firm to obtain accreditation for the sampling and compliance analysis of fertilizing residual materials (FRMs).

Our experienced professionals can calculate the volumes to be treated and analyze the required parameters to ensure the quality of biosolids and the safety of their application on fields.

Contact Avizo Experts-Conseils’ specialists in aerated lagoon sludge measurement and the beneficial use of fertilizing residual materials for a quote.

References

• Matières résiduelles fertilisantes (MRF), on the website of Quebec’s Ministère de l’Environnement, de la Lutte contre les changements climatiques, de la Faune et des Parcs
• Guide sur le recyclage des matières résiduelles fertilisantes, on the website of Quebec’s Ministère de l’Environnement, de la Lutte contre les changements climatiques, de la Faune et des Parcs