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FeuerTRUTZ-International-2-2016

TECHNOLOGY AND TRENDS Fig. 2: High pressure pump station extinguishing systems on ships in the past resulted in the bilge filling with extinguishing water and thus, in some cases to capsizing. For this reason, many tests were carried out about 50 years ago to achieve a greater extinguishing effect with little effort. This was achieved by a very fine atomisation of the water using high pressure pumps (60 to 120 bar). This does not only cool down the flame zones but also generates steam when the fine water droplets with their large surface area hit high fire temperatures. An additional smothering effect is achieved in this manner. Moreover, steam is currently the most economical oxygen displacer by far, amongst others as only approx. 10% of the water consumption of conventional sprinkler systems is required. When the extreme heat encounters the fine high-pressure water mist, approx. 1,650 litres of steam are produced from 1 litre of water. Principally, one can consider this system as a gas extinguisher system. The basis for the calculation for dimensioning the systems is accordingly not the area to be protected, but the room volume to be protected is taken as a basis. As very little water is used, a significantly smaller pipe cross-section is required for this extinguishing method than for conventional sprinkler systems. The crosssection of the main pipes in the nozzle network must only be 25 to 48 mm instead of 100 to 150 mm. The complicated precontrol is also usually omitted as, due to the high-pressure, the response times up to the first extinguishing water discharge from the furthest nozzle corresponds to the required water pouring times. Another aspect that should not be disregarded is the binding of the ascending soot particles. Moreover, greater proportions of the water-soluble fire gases can be washed out. Protective area can be reached in a safe manner horizontally up to 6 m and vertically up to 11 m. As a redundant power supply is not always possible with some protected objects, New extinguishing methods Extinguishing method / media Priority effect High-pressure fine spray extinguishing systems Smothering effect Low-pressure fine spray extinguishing systems Smothering effect One Seven (compressed air foam extinguishing system) Cooling effect Nitrogen inertization Permanent oxygen reduction Vacuum extinguishing method Immediate reduction of oxygen Hot foam Pressureless smothering effect – Smoke-binding Gel extinguisher Smothering effect PyroBubbles (hollow glass spheres) Smothering effect Steam (water mist) Smothering effect Novec 1230 (special extinguishing agent) Terminates the reaction chains F-500 (extinguishing foam) Cooling effect Potassium Terminates the reaction chains high-pressure fine spray extinguishing systems can also be operated by gas-driven high pressure pumps (200 bar). In doing so, the pressurization works completely without electric energy. Instead of this, a battery on nitrogen or compressed air bottles serves as drive energy. During extinguishing operations, then a mixture of two substances leaves the nozzles without impairing the extinguishing procedure. In an idle state, the extinguishing agent water in the system is maintained at a Fig. 3: High-pressure fine spray nozzle FeuerTRUTZ International #.2016 23


FeuerTRUTZ-International-2-2016
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