【 Weak current College 】 various extinguishing agent of environmental effects and economic analysis

Once blockbuster halon fire extinguishing agent appeared in the 20th century, the country's 64 years of the introduction and study of halon fire extinguishing system, in the early 1980s the standard began to introduce relevant norms. Halon fire extinguishing agent is replaced with halogen Atom alkanes compounds in some or all of the hydrogen atom is the generated has a fire-fighting capability of compounds collectively, also known as Halon (halons) extinguishing agent. As a cleaning agent has been greatly generalization, widely used in various kinds of power electronic equipment room. The 1970s found halon to undermine one of the main atmospheric ozone layer. As 1991, the Montreal Protocol, a variety of new fire extinguishing agent, is emerging. Valuable equipment room of gas fire extinguishing agent, its environmental effects, the efficiency and effectiveness has always been in the industry.
1. carbon dioxide
Carbon dioxide (CO2) is one of the Earth's atmospheric composition, used as the extinguishing agent began in the 19th century, China is the CO2 fire-extinguishing system design specifications ". It in normal temperature and pressure is a colorless, tasteless, non-conductive, chemistry is neutral, non-corrosive gas, can be used to archive, electronic equipment room and etc. The fire-fighting mechanism is diluted oxygen, suffocation, also have a cooling effect. However, heavy use of CO2 cause global climate warming will also not be neglected. While the CO2 is also have low toxicity, concentration of up to 20% of the deaths. Whereas minimum fire extinguishing concentration but to 34% (electronic room design concentration > 40%). Despite delay 10S ~ 60S to evacuate the protection area personnel measures, but accidents may, maiming domestic also. In addition, the Jet has a relatively strong when chilling effect on the recording device is influential. Then a dispute because CO2 is causing three Atomic molecular structure, the "greenhouse effect" of the Earth. Accordingly, CO2 in the equipment room often someone should be carefully applied, but because of its good fire extinguishing performance and pharmacy prices at extremely low is worth in other necessary places to promote.
2.FM200
FM200 aka HFC-227ea heptafluoropropane or. Gaseous at normal temperature, colorless, odorless, non-conductive, non-corrosive, non-environmental restrictions. Its mechanism and halon fire extinguishing, to break the chain of fire burning extremely fast. FM200 in electronic equipment room of fire extinguishing concentration is 8%, harmless to the human body. Spray mist and must freeze function, but does not seriously affect visibility and evacuation. FM200 slightly higher concentration than design, its performance characteristics are similar to halon 1301, in some places more security than 1301. Its biggest drawback is the pharmaceutical price for 1301 pharmaceutical 2.5 times. At present there are more than one device manufacturer, China's "heptafluoropropane clean gas fire-extinguishing system design code (approval) has been introduced, which marks the FM200 as halon transitional substitutes in China will be widely applied.
3.INERGEN
INERGEN (inergen) is nitrogen, argon, carbon dioxide to 52: 40: 8 ratio of volume of an extinguishing agent. Its three components were not active gases, as basic constituents of the atmosphere. Inergen gas colorless, tasteless, non-conductive, non-corrosive, non-environmental restrictions in the extinguishing process without any decomposition. The fire-fighting mechanism for diluted oxygen, smothering. One of the main stimulate human CO2 of respiration, so that the body can not continue below the combustion of oxygen concentration is still able to breathe through increased depth and speed up the respiratory rate and get enough oxygen. Gas injection into the ambient temperature changes, and do not impact visibility, better control design concentration can be said to be a more perfect fire extinguishing agent. Its disadvantage is when noise spews; to gaseous form storage, storage cylinder group number; storage pressure, at normal temperature (210C), high pressure for increased 15Mpa risk, it is relatively easy to leak, pipe fitting materials, installation, maintenance of high level requirements; the cost. China's no INERGEN related specification, if adopted, would also like to pass fire station, organization of expert certification.
4. with aerosols
Aerosol is a smoke-fire extinguishing agent, its particles through the oxidant, reducing agents and bonded fabrics combined with a solid material combustion. Has a high dispersion, high concentration of features, most of the particles with diameter less than 1 μ m. Aerosol with fire extinguishing efficiency high and low prices. Its main disadvantage is: in combustion reaction when large amounts of heat, causing the temperature to rise, possibly on the vents in the former 1m or objects. Aerosol spray is placed after the field is white metal salts powders. Visibility is very low, directly affect the evacuation. Aerosol formation of high concentration in the air, water and colloid contains metal salt composition, reduce air resistance. Particulate matter with strong adsorption capacity, it is easy to glue in the circuit boards and electronic tablet, its electrical conductivity and corrosion significantly shorten equipment life. Aerosol toxic, although its toxicity is not big, but still has potential to harm the human body. In fact, aerosol itself does not belong to the cleaning agent, domestic and overseas are no relevant national standards, as well as with electronic equipment room of basic environmental requirements that apply to these sites should be cautious.
5.SDE
SDE is a new type of green-friendly fire extinguishing agent, the main raw material is natural carbon materials, gas catalysts, gas rate stabilizer, oxidation of cooling agent, etc. Appearance of light brown powder or granules and solid-body. Generated gas products is 35% 25% CO2, N2, 39% gaseous water, 1% metal oxide. Fit to fight A, B, C class and electric cable fire. The fire-fighting mechanism is based on physical, chemical, water spray to cool fire three ways at all drowned fighting form.
SDE has the following advantages: (1) high security, storage, transport status is at normal temperature and pressure, automatic pipe fire suppression system SDE job stress .6mpa, no pressure in the pipe fire suppression equipment 0.3Mpa following. (2) to solid-state storage, storage appliance covers small, saves the construction investment. (3) fire extinguishing rate fast and cheap, SDE comprehensive cost ratioLow-voltage 30% CO2. Its disadvantage is sprayed into the gas mixtures for gas atomised particles, although not conductive, transparency is not good, affect the evacuation. SDE fire extinguishing system has been the local standards of the Jiangsu Province SDE gas fire-extinguishing system design, installation, acceptance of (DB32/399-2000). Design can reference implementation.