Environmentally Friendly Fire-Extinguishing Powders
Development of Novel Environmentally Friendly, Non-Halogen, Nontoxic, High-Efficiency Fire-Extinguishing Powders on the Basis of Clay Shales, Zeolites and Perlites
Tech Area / Field
- CHE-THE/Physical and Theoretical Chemistry/Chemistry
3 Approved without Funding
G. Tsulukidze Mining Institute, Georgia, Tbilisi
- Sukhumi Institute of Physics and Technology, Georgia, Tbilisi
- Wessex Institute of Technology, UK, Southampton\nDr. Horst Hejny Consulting, Germany, Dinslaken
Project summaryThe objective of the project is to develop non-halogen, non toxic, environmentally friendly, universal, composite fire-extinguish powders with following main advantages:
- high exploitation properties and extinguishing ability;
- High efficiency;
- 1.5-2 times cheaper than imported analogues;
- Universal; they will be used to extinguish the fires of almost all type at surface structures and underground ones, nuclear stations and nuclear means of transport;
- can be used in wide temperature range (-500C - +500C), including low temperatures (where CO2, water and chladones can’t be used);
- Will have both: homogeneous and heterogeneous extinguishing effect.
Domestic mineral row materials (clay shales, zeolites and perlites of Aspid group) will be utilized for fabrication of new fire-extinguish powders.
At present among the existing extinguishers, in comparison with all fire-extinguish means, the production of fire-extinguish powders occupies 80% in Europe and 60% in Russia. Approximately 130 various foreign companies and factories are involved in the production and supply of such powders. Imported powders of in-series production slightly differ from one another and were not changed practically over last 30 years. Serial production powders do not meet modern requirements, and especially in terms of it universal and practical use. It should be noted that most of them contain Halogen, and as you know their distribution into atmosphere results in ozone layer break down. Moreover, it should be noted that even the cheapest fire-extinguish powders of foreign production are 1.5-2 times expensive than of domestic production.
Thus to accomplish the goal of proposed Project is to elaborate non-halogen, nontoxic, environmentally friendly, high efficient, universal, composite fire-extinguish powders on the basis of domestic mineral raw materials such as clay shales, zeolites and perlits. The proposed method of obtaining composite powders does not require technological expensive chemical processing and modification with halogen-inclusive hydrofobizative additives.
By preliminary investigations, (performed within the Project GNSF/ST07/4-184, funded by Georgian national science foundation):
- Raw materials: clay shales, zeolites and perlites have been selected according to their mineralogical content and indicative factors for reduction of burning process allowed by their thermal and thermo gravimetric analyses.
- Operational properties of powders are as folows: dispersity, powder moisture content and tendency to humidity, tendency consolidation and caking, powder flow and storage duration. Consolidation and caking properties are very important, as the increase of those values accounts for the drastic decrease and complete loss of fire extinguishing resources.
- Optimal particle sizes have been selected in the range that consolidation and caking values to be low, and powder feeding convenient. At the same time particle sizes should be suitable for their rapid heating and destruction, i.e., homogeneous action of combustion products on the flame as well as a heterogeneous inhibition of combustion process will be underway.
Methods of investigations: Fire extinguishing ability will be assessed by reciprocal value of extinguishing “surface” concentration -1/Cn·S. Heterogeneous inhibition will be assessed by coefficient of atomic oxygen recombination on powder surface – µ, to be defined via ESR method. The study of relationship between coefficient of atomic oxygen recombination on γ0, and reciprocal value of extinguishing “surface” concentration -1/Cn·S, alow to establish extinguishing mechanizms.
Experimental methodology will be developed for the study of homogenous effect during the project implementation to define extinguishing properties under different conditions and types of fires. That will allow defining: minimal specific amount of the powder (Gmin) and “surface” concentration Cn·S.
The study of relationship between coefficient of atomic oxygen recombination on γ0, and reciprocal value of extinguishing “surface” concentration -1/Cn·S, alow to establish extenguishing mechanizms.
In concrete cases, powder selection will be conducted according to fire load, therefore the following conditions to be established:
- Conditions for effective usage, a) powder validity – compatibility of powder with burning material; powder feeding regime; minimal specific amount of the powder (Gmin); feeding intensity (I) and extinguish duration (τ).
- Conditions of efficient suppression: fire extinguish duration (τ) dependence on the intensity of powder feeding (I); τ = f(I) which will permit to calculate specific consumption of the powder if necessary (G=Iτ).
- Dependence of powder’s specific consumption on the intensity of powder feeding – G=f(I) to be established. A curve minimum turning point corresponds to optimal conditions of extinguishing.
Expected results: As for the scientific and technical outcomes of the Project it is planned their utilization in normalization process of the large scale fire extinguishing methods. Considering the existing information about powder extinguishers, our product should be targeted for the companies dealing with the production of similar products.
Under the umbrella of the Project appropriate patent applications will be prepared concerning powder extinguishers. Simultaneously works to achieve European Certification for them will be carried out as well.
The Project will result in strong recourses for setting up a commercial company.