Code of practice for managing particulate matter emissions in the potash sector: executive summary

Official title: Code of practice for the management of PM2.5 emissions in the potash sector in Canada

Executive summary

Federal, provincial and territorial environment ministers are taking action to better protect human health and the environment by endorsing and implementing the new Air Quality Management System (AQMS). The AQMS includes Canadian Ambient Air Quality Standards for fine particulate matter (PM2.5) and ground-level ozone, base level industrial emissions requirements (BLIERs) and local air zone management by the provincial/territorial jurisdictions. For the potash sector, a qualitative BLIER (in the form of a code of practice) was developed for fine particulate matter with a mean aerodynamic diameter of less than 2.5 microns (PM2.5).

The overall objective of the code is to identify and promote best practices in the Canadian potash sector with respect to PM2.5 emissions. The code was developed by Environment and Climate Change Canada in consultation with potash industry representatives and the provinces of Saskatchewan and New Brunswick. Information on best management practices was drawn from various sources such as consulting reports, literature and environmental codes by provinces/territories, Environment and Climate Change Canada and the United States Environmental Protection Agency (U.S. EPA), as well as from individual potash companies and technical journals.

There are currently ten potash facilities operating in Canada: all situated in Saskatchewan. An eleventh facility, located in New Brunswick, was placed on care and maintenance in January 2016. Potash mining in Canada is carried out by means of two distinct methods, conventional underground mining and solution mining. Conventional mining is the process of tunneling below the earth and removing ore deposits from the mine’s walls, and transporting it to the surface for wet processing. Solution mining is an alternative method where unsaturated brine is injected into the underground ore deposit through wells to dissolve potassium chloride (KCl), which is then pumped to the surface for processing. In both cases the ore must be dried, screened, and often compacted to produce marketable products. Nine of Canada’s potash facilities are conventional mines, and two are solution mines.

The major processing activities of the sector, drying and compacting, are the primary sources of PM2.5 emissions. They represent about 80% of sector emissions. The remaining 20% are from the fugitive, loadout, and mine exhaust emissions. Table S-1 lists the 15 recommendations designed to limit PM2.5 emissions from these sources.

The code describes the sector’s mining and processing activities in Section 2. Section 3 elaborates on the PM2.5 emissions produced by these activities. The recommended work practices intended to control and minimize these emissions are set out in Section 4. Finally, Section 5 outlines a strategy for implementing the code, along with recommendations for reviewing, reporting, and recordkeeping.

This code is designed to be used by the potash industry, or by regulatory agencies and the general public as a source of technical and policy guidance. However, it does not negate any regulatory requirements.

The code does not require an existing facility to make major technological changes, but rather implement and enhance monitoring and maintenance of its existing abatement equipment. Finally, the recommendations in this code should be incorporated into the initial design stages of new facilities to control and minimize PM2.5 emissions.

Table S-1: List of recommendations (emission control devices)
Subject Recommendation Sources targeted
Wet scrubbers R01 - For venturi scrubbers, continuously monitor and record daily average gas flow rate and pressure drop, daily average brine/water flow rate, and daily average fan amperage; calculate liquid-to-gas L/G ratio daily. S5 - Drying
S6 - Screening
S7 - Compacting
S8 - Material handling
Wet scrubbers R02 - For non-venturi scrubbers, continuously monitor and record daily average gas flow rate, brine/water flow rate, daily brine nozzle pressure, and daily average fan amperage; calculate L/G ratio daily. S5 - Drying
S6 - Screening
S7 - Compacting
S8 - Material handling
Wet scrubbers R03 - Implement maintenance practices specific to wet scrubbers. S5 - Drying
S6 - Screening
S7 - Compacting
S8 - Material handling
Wet scrubbers R04 - For those facilities equipped with brine scrubber recirculation monitoring systems, monitor changes in the brine specific gravity (SG) at regular intervals. S5 - Drying
S6 - Screening
S7 - Compacting
S8 - Material handling
Baghouses R05 - Continuously monitor the daily average pressure drop and average fan amperage of all baghouses. S5 - Drying
S6 - Screening
S7 - Compacting
S8 - Material handling
Baghouses R06 - For those facitities equipped with Baghouse Leak Detection Systems (BLDS), monitor their voltage continuously. S5 - Drying
S6 - Screening
S7 - Compacting
S8 - Material handling
Baghouses R07 - Implement maintenance practices specific to baghouses. S6 - Screening
S7 - Compacting
S8 - Material handling
Electrostatic precipitators R08 - Continuously monitor the secondary current and secondary voltage of all electrostatic precipitators. As needed, monitor the spark rate. S5 - Drying
Electrostatic precipitators R09 - Implement maintenance practices specific to electrostatic precipitators. S5 - Drying
Table S-1 (continued): List of recommendations (emission control devices - general)
Subject Recommendation Sources gargeted
General R10 - Implement recordkeeping of monitoring and excursion evaluation for all emission-control devices at significant sources. S5 - Drying
S7 - Compacting
Cyclones R11 - Implement maintenance practices specific to cyclones. S5 - Drying
S6 - Screening
S7 - Compacting
S8 - Material handling
Table S-1 (continued): List of recommendations (dryers and compactors - maintenance)
Subject Recommendation Sources targeted
Drying R12 - Ensure there are no leaks in the dryer air discharge system that would allow dust to escape. S5 - Drying
Compacting R13 - Ensure that compactor hoods and ducting are fitted properly and have no cracks to prevent dust from escaping. S7 - Compacting
Table S-1 (continued): List of recommendations (material handling practices)
Subject Recommendation Sources targeted
Material storage, handling, conveying R14 - Optimize material handling, storage, and conveying practices. S8 - Material handling
Table S-1 (continued): List of recommendations (environmental management practices)
Subject Recommendation Sources targeted
Management practicesa R15 - Develop and implement broad-based best practices for general environmental management S1 - Subsurface operations
S2 - Well drilling
S3 - Dry crushing
S4 - Evaporation and crystallization
S5 - Drying
S6 - Screening
S7 - Compacting
S8 - Material handling

a Environmental management practices are referred to in Environment Canada’s Environmental Code of Practice for Metal Mines, 2009. Many of these practices can also be applied to the potash mining industry.

Report a problem or mistake on this page
Please select all that apply:

Thank you for your help!

You will not receive a reply. For enquiries, contact us.

Date modified: