Suchergebnisse

The process of enrichment of potash ore using industrial oils as a hydrophobizing agent in the collective mixture of potassium chloride, which is a composition of salts of higher aliphatic amines, pine oil and polyethylene glycol PEG- 400, has been investigated. A comparative analysis of the influence of industrial oils I-8A, I-12A, I-30A and liquid paraffins on the technological parameters of potash ore flotation has been carried out. The influence of hydrophobizing additives on the adsorption of amine on potassium chloride crystals was investigated by infrared spectroscopy. It has been established that the introduction of industrial oils into the flotation system ensures the recovery of potassium chloride at the same level as when using a collective mixture with liquid paraffins. The best flotation performance when using industrial oils is possible by increasing the consumption of the apolar reagent.

During operation of livestock complexes in small spaces, a large amount of animal excretions (feces, urine and undigested food) is generated, which can lead to air pollution, constant smell and release of toxic gases. With increase in productivity of complexes, complaints from residents of settlements located in the immediate vicinity of the facility increase, and pig breeding complexes in this case are no exception. Unpleasant odor is a powerful irritating factor having a significant negative impact on the life and health of people living near livestock complexes, which reduces their living standards. Often, the need to constantly monitor presence of unpleasant odor is the limiting factor for modification, expansion of existing pig farms or creation of new ones, as well as for increasing their productivity and profitability. In this research, studies were carried out for selection of chemical reagents composition for the purpose of deodorization and neutralization of liquid manure runoff at pig-breeding complex. It has been determined that composition based on ammonium persulfate with peracetic acid and formalin, as well as a composition based on sodium nitrite with ammonium molybdate (a high deodorizing effect was maintained after 21 days of exposure to the moment of introduction of reagents into manure) was the most preferable in terms of maintaining the disinfecting effect and suppressing bad odor over the long term. The manure mixtures obtained as a result of such treatment do not pose danger to the environment and can be used as the main component of complex organomineral fertilizers.

Complaints on unpleasant odor occurring near pig-breeding complexes and frequently, at a considerable distance from them, are one of the key factors that are limiting the development of pig-breeding industry. Unpleasant odor takes place as a result of anaerobic decomposition of the manure and also due to liquid slurry at the pig-breeding facility. Despite the fact, that the effect of unpleasant odor on human health is under-investigated, the people suffer natural aversion to the smell of manure. The smell of swine manure can be an unpleasant factor affecting the quality of the life of people living in the cities close to the pig-breeding complexes and also have an effect on the price of the real estate located within this area. Tightening of standards regulating the level of odor can also be a limiting factor for this branch of industry. Detailed research aimed at the selection of the optional composition of chemical reagents for deodoration and disinfection of liquid slurry waste at a pig breeding complex is presented. It has been determined, that the effect of disinfection and suppression of unpleasant odor for a long time is provided by the composition of ammonium persulphate, peracetic acid and formalin, the composition that contains sulphuric acid, sodium hypochlorite and sodium hydroxide and finally, the composition that contains sodium nitrite and ammonium molybdate. It was showed that the abovementioned mixtures are effective in relation to the samples of manure in laboratory (the volume of manure taken for the experiment was 200-400 ml), as well as semi-industrial conditions (the volume of manure – 80 liters). The manure mixtures obtained as a result of such treatment are environmentally friendly and can be used for the production of organo-mineral fertilizers.

The effect of foaming agents of different chemical nature (amyl alcohol, glycolic ether, pine oil) on the flotation of halite from polyhalite ores using alkylmorpholine as a collector was investigated. It was established that the combined adding of amyl alcohol with alkylmorpholine and glycolic ether with alkylmorpholine in the process of sodium chloride flotation allows achieving high technological performance and reduces the consumption of expensive alkylmorpholine by 2 times. The use of pine oil as a foaming agent in a mixture with alkylmorpholine has been established to reduce the collector consumption by 2.2 times.

Due to the fact that polyhalite ores are poorly soluble in water, it was of interest to study the method of their processing using acids. The influence of polyhalite size, the hydrochloric acid concentration and consumption, the ratio of L: S, the temperature and time of mixing the pulp on the useful components extraction into the solution have been studied. The optimal conditions for the decomposition of polyhalite with hydrochloric acid have been determined. The degree of useful components extraction into the solution depends on the concentration of hydrochloric acid or on the L:S ratio of the pulp, but in all cases the decomposition of polyhalite occurs without secondary crystal formation, as evidenced by the same degree of potassium and magnesium ions extraction. The degree of potassium and magnesium ions extraction from polyhalite into solution increases with decomposition process temperature, an increase in the consumption of acid and the duration of the reagents interaction, and decreases with increasing acid concentration. The CaSO4 content in the solution increases sharply with an increase in the HCl concentration and is practically independent of the process temperature. Hydrochloric acid extract can be used for phosphate raw decomposition in order to obtain complex fertilizers.

Totally water soluble compositions of NPK-fertilizers containing microelements in chelate form were developed. The methods of synthesis of chelate complexes of the most important microelements were optimized, the structure of obtained compounds was confirmed by X-ray phase analysis, IR-spectroscopy and elemental analysis. Obtained compositions of fertilizers are perspective for the incorporation on technical chlorophobic and fruit-berry crops using different agricultural machinery.

Single-stage process of obtaining active carbon by thermal processing of plant raw materials (mixture of different types of wood sawdust) impregnated with the mixture of phosphoric acid, urea and nitric acid salts has been developed. Active influence of impregnates on the process of carbonization and formation of carbon residue has been demonstrated. It is established that carbon residue obtained in the interval of heating 20–700 °С possesses high sorption activity to the vapors of organic compounds and has ion-exchange capacity. It has been shown that the value of carbon residue depending on the impregnate used in the wood increases by 3,1 times at 600 °С and by 4,2 times – at 700 °С as compared to the yield of non-treated initial raw materials.

The influence of the main parameters on the process of obtaining artificial carnallite and its quality has been established. It is shown that to obtain a product with a high content of the carnallite phase and a low content of bischofite and KCl, it is necessary to use magnesium chloride solution with the concentration of 27-30 % and preheated ground potassium chloride. The process should be carried out at the temperature of 80 °C. The formation of synthetic carnallite, close in composition to the enriched one, occurs when the ratio of potassium chloride to magnesium chloride in the initial mixture is equal or close to their stoichiometric ratio in carnallite. With an excess of potassium chloride in the reaction mixture, an increased content of potassium and sodium chlorides in the product is observed, and with its deficiency, the product contains an increased amount of bischofite phase. To reduce the hydrolysis of magnesium chloride during dehydration, a slight excess of potassium chloride should be maintained in the mixture entering the synthesis. It is shown that the most advantageous scheme for producing artificial carnallite provides for incomplete evaporation of desulfurized liquor in the presence of potassium chloride with the return of circulating carnallite liquor to the desulfurization stage.

The excess of magnesium chloride brines is formed during the polymineral ores processing in order to obtain potassium sulfate. One way to regenerate such brines is to produce artificial carnallite. It is necessary to purify these brines from sulfates for their further use as raw materials for the artificial carnallite production. In this work, the process of desulfurization of magnesium chloride brines with a solution of calcium chloride is studied. The temperature and the processing time, the magnesium chloride solutions concentration and the consumption of desulfurizing agent (calcium chloride) influence on the degree of magnesium chloride solutions purification from sulfate ions was determined. It has been established that almost all sulfate ions interact with calcium ion in 15 minutes and the desulfurization degree reaches 98,08 %. The increase in duration of the suspension mixing is necessary in order to establish equilibrium in the system and relieve the supersaturation in the solution. It has been shown that with increasing solutions saturation with MgCl2, the degree of the magnesium chloride brines purification from SO4 2– ion increases. Complete precipitation of calcium sulfate requires a certain excess concentration of calcium chloride.