In this study, benzo(a)pyrene-water-oxygen systems were investigated in wide ranges of change of temperature value and initial components to predict in which conditions benzo(a)pyrene degraded into more harmful substances. Consequently, the thermodynamic parameters of the benzo(a) pyrene-water-oxygen system were calculated and the concentration distribution of carbon, hydrogen and oxygen-containing particles in the gas phase were established. Adding water into the system allowed decreasing of carbon and acetylene. These elements are the key elements of benzo(a)pyrene formation. According to this, the main parameter for reducing the concentration of benzo(a)pyrene in the gas phase was the water content in fuel oil within 10-15%. Determination of the concentration of benzo(a)pyrene in samples of flue gases of DKVR-4/13 and PTVM-30M boiler units of the Teplokommunoenergo heating organization of Bishkek city was carried out by chromatographic method. Concentrations of benzo(a)pyrene were found to compare the product of burning ordinary fuel oil and water fuel emulsion. Homogenization of the fuel-air mixture by adding water to the fuel oil allowed us to obtain an inverse emulsion and reduce the concentration of benzo(a)pyrene in flue gases up to 62%. According to this, a new process flowsheet of water fuel emulsions production was proposed for the heating organization.

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In this study, thermodynamic modelling of the process of thermal destruction of oil-contaminated soil of Ozenmunaigas JSC, which includes compounds such as carbon, silicon, aluminum, iron, calcium, magnesium, sodium, potassium, chromium, phosphorus, manganese, copper, titanium, molybdenum, nickel, vanadium, and water, was carried out. The physicochemical and thermodynamic parameters of the complex system were calculated at P=0.1 MPa, T=598-3000 K. The concentration distribution of components, particles, and condensed phases in the gas phase has been established. In the process of thermal destruction of oil-contaminated soil, the formation of condensed phases was as follows: SiO2(c), Al2O3(c), AlO3H3(c), Cu(c), Cu2O(c), FeO(c), Fe2O3(c), Fe3O4(c), Fe2SiO4(c), NiO(c), MnO(c), Mn3O4(c), MnO2H2(c), Cr2O3(c), MoO2(c), V2O3(c), V2O4(c), TiO2(c), MgSiO3(c), Mg2SiO4(c), MgTi2O5(c), Ca3P2O8(c), Mg2SiO4(c), MgTi2O5(c), Ca3P2O8(c), CaCO3(c), CaSiO3(c), CaTiO3(c), Na2Si2O5(c), K2Si4O9(c). At the same time, the amount of condensed calcium silicate CaSiO3(c) was significant and amounted to 3.2 mol/kg, which is due to the initial standard content of oxides of the type (g/kg): SiO2-473,7, CaO-181,5 in oil-contaminated soil. The formation of various types of condensed phases (from 10-30 to 10-4 mol/kg) during thermal degradation can help reduce the synergism and toxicity of metal particles in oil-contaminated soils. In the process of thermal destruction of oil-contaminated soil, its carbon-containing components (mg/kg: С12-6,27; С13-10,98; С14-15,69; С15-18,82; С16-23,52; С17-31,37; С18-27,80; С19-17,25; С20-29,80) were mainly converted into oxide, carbon dioxide, and water, and thereby neutralized the organic mass of the soil.

In this paper, the fuel oil-water-air system at a wide temperature range (T=500-3000K) was studied and the ratio of gas-liquid flows (water content in fuel oil 5-15%) at the maximum entropy of the system and the formation of soot in flue gases was revealed. To reduce the concentration of soot in flue gases, a fuel oil-water emulsion was used. The particle sizes of the fuel oil-water emulsion were determined by sedimentation analysis. It is shown that they have a polydisperse character (diameter from 8.96 to 59.02 μm). The water content in fuel oil during the preparation of fuel oil-water emulsion in the boiler room was controlled by a capacitive sensor. The water flow was automatically maintained by an ejector-dosing device. The thermodynamic parameters of the system (entropy, enthalpy, internal energy) were calculated and their comparative characteristics were obtained. The concentration distribution of hydrogen, carbon, nitrogen, sulfur and oxygen containing molecules, particles and condensed phases in the gas phase has been established. During the combustion of the fuel oil-water emulsion, the concentration of soot in the gas phase decreased due to an increase in hydrogen-containing particles in the gas phase, i.e. an increase in the H/C ratio, as well as a change in the concentration of condensed carbon (mol/kg): (fuel oil without water C(c) = 63.3 mol/kg); fuel oil with water: 5% H2O, C(c) = 54.96; 10% H2O, C(c) = 50.45; 15% H2O, C(c) = 46.3. It is noted that the H/C ratio in the case of burning fuel oil -water emulsion is 2.26 times higher. A technological scheme for the preparation and combustion of fuel oil in the form of fuel oil-water emulsions in industrial boilers of the E-1/9-M(3) type of the Bridge Construction Detachment of the Kyrgyz Railway, Bishkek, has been developed. It has been established that when burning fuel oil-water emulsions in boiler units, the soot content in flue gases is reduced by 75% due to the developed contact surface of the interacting phases and more complete combustion of particles of fuel oil-water emulsions.

The disposal of municipal solid wastes (MSW) is one of the important issues today. The MSW is generally disposed of in a landfill. The disintegration of wastes in landfill generates the wastewater known as leachate and it became one of the budding environmental impacts. The landfill leachate seeps into natural ponds next to the Bishkek (Kyrgyzstan) landfill. The MSWs are dumped with an irregular landfill in Bishkek, and it has been observed that this situation creates many environmental pollution problems (air pollution due to the combustion of wastes and generated biogas, due to leakage of leachate from the landfill) around the landfill. The leachate in the ponds is not treated and leaks into the environment. In this study, the potential of the coagulation-flocculation(CF) and electrooxidation (EO) processes was investigated for the treatment of leachate from the sanitary landfill located in Bishkek-Kyrgyzstan. The initial COD (1400 ± 50 mg/L), TOC (540 ± 15 mg/L), and ammonia nitrogen (315 ± 10 mg/L) from landfill leachate were treated by the CF process as 33, 23, and 14% at pH 6.5 with alum dosage of 5 g/L, and 40, 29 and 10.1% at pH 8.5 with ferric chloride dosage of 5 g/L, respectively.Removal efficiencies at applied currents of 1.0, 3.0, and 5.0 A with an EO reactor using borondoped diamond (BDD) plate anode and stainless steel (SS) plate cathode were 67.20, 88.30, and 97.90% for COD, 60.10, 85.38, and 95.53% for TOC, and 48.9, 94.6 and 99.8% for ammonia nitrogen, respectively. As a result, it was seen that Bishkek's irregular solid waste landfilling leachate, which causes environmental pollution, was effectively treated with the EO process. By establishing a regular landfill, Bishkek municipal solid wastes must be disposed of in the landfill and treated of the leachate.