Burning High-Ash Coals
Development of Environmentally Friendly Technology of Alumina Manufacturing from Non Utilizable Wastes of Cleaning and Burning of High-Ash Coal for Processing on Aluminum
Tech Area / Field
- CHE-IND/Industrial Chemistry and Chemical Process Engineering/Chemistry
- ENV-WDS/Waste Disposal/Environment
- NNE-EPP/Electric Power Production/Non-Nuclear Energy
3 Approved without Funding
Institute of Metallurgy, Georgia, Tbilisi
- NAICOM, Belgium, Hastière-par-delà\nPacific Northwest National Laboratory, USA, WA, Richland
Objective of the project is manufacturing of Metallurgical Alumina from non utilizable waste products of cleaning and burning High – Ash Coals, improvement of an ecological conditions in territories of accumulation of dump products of Mining and Power Industries.
Another objective is processing of the received Metallurgical Alumina on Aluminum Metal, decrease of the industrial expenses.
State of the art in the field
In conditions of reduction of natural resources of high-quality coals, intensive research and development works on involving in Power Industry low-grade, small size fraction coals are carried out. For example, development of the new power retrofits for burning of coals in a boiling layer, gasification of coals in gas generators, with gassing synthesis (processes "KOGAZ", "WINKLER", "SINTAIN", etc.). However, these processes does not solve a problem of qualified use of, High – Ash Coals non utilizable waste products of cleaning and burning which stockpiling now are estimated hundreds millions tons, that significant deterioration of an ecological atmosphere in dump territories.
On the other hand, also there is a problem of manufacturing conditioned Metallurgical Alumina for processing on Aluminum Metal as natural resources of high-quality Bauxites with the low - containing Silica are considerably exhausted. Modern methods of use of low-grade raw materials, for example hydro chemical methods, Bayer's sintering method, etc., have essential lacks to which it is possible to attribution sequential processes, the considerable charge of various expensive reagents (Na, Ca, Mg - Alkali, Na - Sulfate, etc.), and the main thing, these methods not providing using of Ashes of Coals, as Alumina containing products.
The problem of involving in Power Industry of low-grade solid energy carriers, as well as for other countries, has great value for Georgia. In the Western Georgia (in area of Tkibuli town - 250 km from capital - Tbilisi) is present a coal deposit, basically representative High – Ash Coal (ashes 35 - 40 %, flying substances 33 - 37 %), which industrial production now is failed, but already stockpiling products of coal cleaning approximately estimated 7 million tons. Therefore revival of manufacture in this region on a basis of environmentally protection technologies will be doubtless to have positive consequences, including ecological, for Republic.
The preliminary researches which have been conducting in Georgian Institute of Metallurgy and Materials Science have proved a real opportunity of development of technology of manufacturing of Metallurgical Alumina on the basis of the above mentioned method, with an output of a suitable product over 90% from quantity of Alumina in initial raw material.
Novelty of the project
Novelty of the project consists in development of unique, practically waste less, environmentally protection technology of manufacturing of Metallurgical Alumina from non utilizable waste products of cleaning and burning of High – Ash Coals, with an opportunity of use of only one by-product – Silica as ingredient of necessary materials for Metallurgical and Building Industries.
The essence of Project technology will be process of low temperature sintering of a mixture of Ammonium Sulfate with Ashes of Coal or with products of it cleaning.
Expected results and their application
Researches results will have scientific, technological and commercial value.
1. Scientific value:
Orthogonal plans, mathematical models will be developed and realized and optimum areas at the maximal extraction of alumina is achieved will be determined.
2. Technological value:
2.1. Unique, practically non waste, environmental friendly technology of manufacturing conditioned Metallurgical Alumina from alumina containing dump products of power repartition, suitable for processing on Aluminum Metal will be developed. Only one by-product formed at it – Silica with impurity of Iron can be used in Metallurgical and Building Industries (as for instance, metals casting, high ways, civil engineering, etc.);
2.2. The output of a suitable product from quantity of Alumina in an initial material will make more than 90 %;
2.3. Realization of the project will provide improvement of ecological conditions in territories of accumulation of dump products of coal and products of their combusting;
Also technological advantages of a suggested method consist in the following:
- Process is carried out without using of the acids worsening ecological conditions;
- It is not required preliminary ashes dehydration for sintering with Ammonium Sulfate;
- Regeneration of Ammonium Sulfate occurs during allocation of Aluminum Hydrate.
3. Commercial value:
3.1. Realization of the project will enable of manufacture of alumina and aluminum in places of a disposition of power installations.
3.2. On the basis of the preliminary economic analysis, in view of market prices on conditioned alumina, the Cost Price of the Electric Power manufacturing in Electric Power Installations with use of coal will approximately decrease not less than for 20 %.
Competence of the project team.
Project participants are high-skilled specialists in the area of chemical technologies and power engineering. In the Former SU they were involved mainly in defenses programs. For the recent 10-15 years these scientists participated in the conversion projects, in particular, investigations of environmental friendly technologies. During the above mentioned period more than 35 scientific works were devoted to these problems, among them 9 works were published in the area of technologies attributed to the submitted project. E.g.: 1. The comparative analysis of emission of radioactive substances in an atmosphere at burning of Tkibuli - Shaori deposits coals and the combustible gases received at their gasification. Scientific and Technology Magazine “Energy”, №1 (33), Tbilisi, 2005, pp. 12-16 (G. Arabidze); 2. The coal industry of Georgia - guarantor of liquidation of basic capacities deficiency of the country". Mining magazine ", №2 (15), 2005, Tbilisi (R. Arveladze); 3. The concept of a non-polluting thermal power station at Georgian coal. Scientific and Technology Magazine “Energy ", №3 (31), Tbilisi, 2004, pp. 25-29 (G. Arabidze); 4. Prospects of multipurpose utilization of соal. Scientific and Technology Magazine “Energy”, №1 (29), Tbilisi, 2004, pp. 16-20 (T. Jishkariani); 5. Electrochemical manufacturing of yttrium - aluminum intermetallide from halogenated melts. Georgian chemical magazine, # 3, 2003, pp. 245 - 248 (G. Kipiani); 5.Using of small class of heat - treated Tkibuli coal in Metallurgical and Power Industries. Processing of ferrous and manganese ores in South Caucasus. “Science”, Tbilisi, 2000, pp. 116- 121 (N. Gonjilashvili, I. Pulariani); 6. Elaboration of technological process of recycling low-grade and secondary raw material of mining and smelting conversion. Problems of Metallurgy, Materials Science and Welding. Tbilisi, GWA, 2002, p. 329-339 (T. Chubinidze, А. Oakley).
Meeting ISTC goals and objectives
The scientific employees that earlier carried out military orders of the Ministry of a Defense Industry, Ministry of a Power Industry and Ministry of Mechanical Engineering of former USSR will be involved in the realization of the project. The support of the project will allow to direct scientific potential of these scientists on realization of researches for the peace purposes on development of new technology in the area of chemistry process engineering, electric power production with environmental protection. Elaboration of the technology will be realized with the minimum expenses if compared with world costs.
The project goals and tasks completely meet national interests of Georgia; it is also provisional for solving the problems of science and technology on the international level.
Role of foreign collaborators
Role of foreign collaborators will consist in mutual discussion of reports, comments on the research of technologies, selective cross-control of the investigation results, joints workshops and publications, promote on technology application.
The International Science and Technology Center (ISTC) is an intergovernmental organization connecting scientists from Kazakhstan, Armenia, Tajikistan, Kyrgyzstan, and Georgia with their peers and research organizations in the EU, Japan, Republic of Korea, Norway and the United States.
ISTC facilitates international science projects and assists the global scientific and business community to source and engage with CIS and Georgian institutes that develop or possess an excellence of scientific know-how.