Paper Technology International 2020 - Journal - Page 22

PAPERTECHNOLOGYINTERNATIONAL
Log Saw, Band Saw and Napkin Folding
Dust Filters – Bag Houses
Fires in these types of enclosures or areas are unfortunately
common and costly. Friction and or dangerous particles, including
sparks generated during the sharpening of the saw blade can ignite
the dust inside the log saw, band saw, or napkin folding enclosure.
As enclosures and areas are generally dusty, fires can easily cause
equipment damage and production downtime.
Ignition sources such as sparks and hot particles generated
in the tissue mill and the converting process can be extracted into
the dust extraction system and cause fires and dust explosions in
the dust filter or bag house. It is therefore vital to also protect this
part of your process.
For protection of log saw, band saw, or napkin folding
machines, Firefly is using the Quick Suppression System concept,
based on quick detection and suppression of flames. Thanks to the
quick response time of the system, production loss and equipment
damage can be minimized.
Water mist, compared to alternative suppression solutions
such as CO2 or powder, is a non-invasive suppression method that
will effectively suppress the potential dangers with a minimum effect
on your production and is harmless to people.
Water mist has another advantage over CO2 as it will be
efficient even if the enclosure is not air-tight. The CO2 gas will only
suppress a fire when the gas concentration is high enough. In case
the gas will leak out of the protected area, the suppression effect will
decrease and eventually not be effective at all. As these enclosures
usually have openings in the lower parts and extraction in the upper
parts, there is a considerable risk that the CO2 gas concentration
will be reduced too quickly.
Personal safety and cost (TCO) are also things to consider
when choosing a suppression system.
Firefly’s dust extraction filter protection systems are based
on our unique True-IR spark detector HD400 that will detect sparks
and hot particles with a temperature down to 400°C (750°F), which
is just below the ignition temperature for cellulose dust according
to NFPA (National Fire Protection Association). At this temperature
the particles are dark, they do not emit light, and Firefly has the only
detectors in the world approved by FM Global to detect hot particles
from 250°C and 400°C, thanks to its True IR technology.
A water spray extinguishing zone is typically installed
downstream of the detectors to eliminate these dangerous particles
from entering into the filter or bag house.
Firefly’s solutions for fire prevention in tissue and paper
conversion processes increase safety in industries around the
world.
Figure 4: Firefly’s Protection of log saw, band saw or napkin
folding consists of extremely quick flame detection in
combination with water mist suppression.
About Firefly
Firefly is a Swedish developer of industrial fire prevention and protection systems for process industries worldwide. Since 1973,
Firefly has specialized in creating customized system solutions of the highest technical standards and quality, based on customer
needs, to increase the level of safety.
Firefly’s products hold national and international approvals and certifications. The company is noted on the OMX/NASDAQ First
North Exchange in Stockholm, Sweden.
In complement to worldwide sales, Firefly also provides its customers with field service, maintenance and guaranteed long-term
spare part supply.
Firefly – Intelligent fire protection that keeps you in production.
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