AdBlue® is not classed as a dangerous good for transport in Australia, and it is far less hazardous than most liquids on a typical depot. That sometimes leads people to assume there are no storage considerations at all. There are. A 1,000 L IBC or a bulk tank that fails or is punctured can put a large volume of urea solution onto the ground or into stormwater, and urea is a nitrogen source that is harmful to creeks and waterways in quantity.
This article covers the general principles. Requirements vary between states, councils, industries and individual sites, so always check with your state EPA, your local council and your own site's rules before finalising a storage setup. Nothing here should be read as a compliance guarantee.
What bunding is and why it's used
A bund is a secondary containment area around a tank or group of containers, designed to hold a spill or leak so it can be cleaned up rather than running off site. It can be:
- A concrete or masonry wall and floor around a storage area.
- A portable bund, pallet bund or spill tray sized for drums or IBCs.
- Built into the tank itself, as in a bunded (double-wall) tank, where an outer skin surrounds the inner tank.
Guidelines commonly relate bund capacity to the volume of the largest container stored, plus a margin, but the exact figures depend on where you are and what else is stored. Your EPA or site safety adviser can tell you what applies.
Bunded tank or single-skin tank?
For bulk AdBlue storage there are two broad options:
- Bunded (double-wall) tank. Containment is part of the tank. It takes up less space than a separate bund, doesn't collect rainwater in an open bund, and is simpler to install on an existing slab. It is often the practical choice for depots, service stations and sites with limited room.
- Single-skin tank. Lower cost, and suitable where secondary containment isn't required or is provided another way, such as an existing bunded area. Some sites place a single-skin tank inside a bunded compound with other storage.
Whichever you choose, the tank and all wetted parts must be AdBlue-compatible: HDPE, polypropylene or stainless steel, with EPDM or fluoroelastomer seals.
Other site storage considerations
Bunding is only one part of a sound setup. Other things that commonly come up in site planning:
- Location. Keep tanks and IBCs away from stormwater drains and waterways, and out of vehicle paths. Bollards or barriers protect against impact.
- Delivery access. A bulk tank needs safe tanker access and a fill point the driver can reach without hoses crossing traffic.
- Overfill protection. A high-level alarm or gauge helps prevent overfilling during delivery, which is one of the more common causes of spills.
- Shade. Storage out of direct sun protects product quality and the tank itself.
- Documentation. Keep the Safety Data Sheet on site and accessible. You can download it from our resources page.
- Bund upkeep. Open bunds collect rainwater. Keep drain valves closed, and inspect and empty bunds regularly so there is always capacity available.
Planning for a spill
Even a well-bunded site should have a plan for spills during dispensing and delivery, which happen outside the bund. The essentials:
- Keep a general purpose or chemical spill kit near the tank or IBC. Oil-only kits won't absorb AdBlue, because they are designed to repel water-based liquids.
- Stop the source if safe to do so: close the valve, stop the pump.
- Contain the spill and stop it reaching drains, using socks or drain covers from the kit.
- Absorb, then rinse the residue with plenty of water. Dried AdBlue leaves white urea crystals.
- Dispose of used absorbent according to your site and local requirements.
Something you can check today: find the stormwater drain nearest your AdBlue storage and work out which way a spill would run. If it would reach that drain before anyone noticed, a drain cover in the spill kit and a clear note on the spill procedure are an easy first fix.
How Liquidia can help
Liquidia supplies single-skin and bunded tanks for AdBlue, with installation and remote level monitoring, plus spill kits suited to water-based liquids. Talk to us about bulk and on-site tank options, or see the spill kits range.