Depureco BL 45 DEX 1/3D INERT

Because the BL 45 INERT is rated T140°C -- 20 degrees lower than its ECOBULL sibling's T160°C. A side-channel blower develops temperatures around 145-155°C on the surface under continuous operation, which is not sufficient for powders with MIT (minimum ignition temperature) below 160°C. A brushless motor stays below T140°C even under fault conditions, and this is why reactive metal powders -- where MIT is often 100-140°C -- can only be collected by a brushless-driven BL 45 INERT. In other words, it is not just "smaller" than the ECOBULL INERT, but has a different safety principle.

The inerting container is an N2-flushed double-walled construction inside the collection tank itself. The user supplies 2-4 bar nitrogen from their own installation via an ATEX-certified quick coupling. The BL 45's distribution valve opens automatically at start-up and maintains a constant N2 flow -- typically 8-15 Nl/min -- throughout the operating period. Oxygen concentration in the container drops from 20.9 % to below 8 % within 60-90 seconds, well below the LOC (limiting oxygen concentration) for most reactive metal powders. No gas is integrated in the BL 45 -- the customer must supply their own N2 tank or generator.

Some reactive metals -- especially aluminium, magnesium and zirconium -- react with water or humid air and form hydrogen gas (H2). H2 is extremely flammable (LEL 4 %, also known as the "flammable hydrogen zone") and can accumulate inside a sealed inerting container. The safety hydrogen vent is a calibrated pressure-relief valve with flame arrester that discharges accumulated H2 outside the collection vessel as soon as pressure exceeds 5-10 mbar. It is mandatory for all inerting collection of reactive metals per EN 14491 and is included on the BL 45 INERT as standard.

It's a pure zone-application difference, not two different units. SKU A1295 is dual-certified: the same physical unit may be used both in Zone 21 with Zone 22 outside (II 1/2D Da/Db -- found on the other slug, bl-45-dex-1-2d-inert) and in Zone 22 + Zone 22 (II 1/3D Da/Dc -- this slug). Price is identical, documentation is identical. We split it into two slugs because it needs to be findable via searches for *both* zone combinations, and because customers who think of it as "a 1/2D machine" do not always cross-reference with a 1/3D list. You receive the same delivery regardless of which slug you order from.

As a rule of thumb: powders with MIT below 100°C (certain nano-aluminium and nano-titanium powders), powders with pyrophoric self-ignition at room temperature (e.g. fine-grained zirconium hydride), and powders that react with N2 itself (e.g. certain magnesium nitride systems). These require either a full gas-isolated system (argon instead of N2) or a custom-built unit. When in doubt: read the powder's SDS safety data sheet, look for "autoignition temperature" and "MIT", and contact us for a review. We have experience with 40+ metal powder lists and can recommend the right setup.

Yes. The N2 feed hose from your nitrogen source to the BL 45's quick coupling must be ATEX-certified for the zone it passes through. If the installation is Zone 22 throughout, an antistatic polyurethane hose with grounded flange ends is sufficient. If it passes through Zone 21, the hose must have ATEX II 2D certification or higher. The nitrogen source itself (tank, generator, dewar) typically stands outside the zone. The regulator and pressure switch on the BL 45 are themselves ATEX-certified as part of the unit.

Under normal reactive-metal-powder operation: once every 4-8 months at 8-hour shifts, or when the pressure-drop gauge on the filter housing exceeds 40 mbar. Reactive metal powders tend to compact faster than ordinary industrial dust, and the cartridge form -- rather than star filter -- is designed to be cleaned with reverse pulse without tearing itself apart. Note that a used filter from INERT service may still contain reactive powder -- it must be handled by trained personnel in N2 atmosphere at replacement. Particulair offers filter replacement as part of a service package.