This study will evaluate the physico-chemical bases and development of new technology for obtaining slow and extended-action fertilizer from potassium-containing alumino-silicates containing potassium, calcium, magnesium and phosphorus. It will also study the agrochemical properties and efficiency of the synthesized as well as field demonstration tests are outlined within the framework of this project. As it is known, over 90 per cent of potassium fertilizers produced in the world is potassium chloride, which is due to chemical composition of the basic potassium-containing deposits, as well as by far the cheaper technology being used to obtain the fertilizer.
Disadvantage of potassium chloride is the high content of chloride. Chloride accumulation is harmful both for the soil and for the plants. Chloride reduces general and gustatory qualities of many farm goods. Ecologically, chloride ion, reaching ground water can be considered an environment hazardous element.
Fertilizer, obtained by our method could be used in organic as well as in conventional agricultural systems.
Water-free potassium-containing alumino-silicates, potassium feldspars (orthoclase), nepheline syenites, leucites, synnerites have industrial importance as potassium-containing rocks.
A new, original method has been developed In the Mineral Salts Lab of the Institute of General and Inorganic Chemistry (IGIC) of the National Science Academy of the Republic of Armenia to process these rocks to obtain fertilizers where potassium, calcium and magnesium are in plant-available form. Proposed method has been tested on dacite tuffs, containing up to 15.2 per cent K2O. The technology does not require large monetary investments.
Some of the agro-chemical properties of the fertilizers have been studied in the Agrochemical lab of the Armenian National Agrarian University of Armenia (ANAU).
Preliminary investigations showed that potassium, calcium, phosphorous and magnesium become mobile, i.e. turn plant-available while treating the dacite tuffs by our method. The produced fertiliser can be considered a slowly release fertilizer as it dissolves slowly in the soil, thus becoming available and a stable nutrient source preserving its availability up to three years, plus circumventing environmental pollution.
Based on the gained experiences on the synthesis of the similar fertilizers agriculturally tested at the Agrarian University of Armenia and at the Solikamsk pilot station of the Russian Federation, a new method of the obtaining the poorly-soluble potassium fertilizers with salient accessory effects is proposed, such as:· High absorbing capacity. Thanks to this, the fertilizer absorbs nutrients vs exchange route, including nitrogen, thus greatly reducing nutrients' leaching, which is also important from the ecological point of view;
· High water-absorbance (500% and more). Absorbs both irrigated and ground waters, which later are used by the plants;
· Enhances the accessibility of soil phosphorous and potassium;
· Enhances drought-resistance of the plants promoting land cultivation in arid and non-irrigating soil zones.
· Ties heavy metal ions (Pb, Hg, As, Cr, Sn, etc.) through non-exchange mechanism where these elements don't enter the plant thus making the harvest free of harmful elements.
· Absorbs positive and negative ions which could substitute other ions.
Successful project implementation would result in the development of theoretical bases as well as the technology for the production of slow and extended-action fertilizer from potassium-containing alumino-silicate rocks with the demonstration test results.
