Vol 104, No 11 (2015)

“Air to air” heat pumps (HP) are intended for residential, industrial and other premises direct heating. The advantages of air heat pumps in comparison with other types of heat pump heating plants are examined. Power indices of an “air to air” heat pump at 1Gigacal/g heat capacity for heating residential premises to provide temperatures from 18 to 26 оС inside the premises when the temperatures of the lowpotential heat source (outdoor air) were from +8 to -40 оС were investigated. During a heating season the use of equivalent fuel was significantly saved as compared with heating using a gas boiler room (365-435 t e.f against 846,2-973,2 t e.f). But at low temperatures of outdoor air (lower -15… -25 оС) heating efficiency of the air heat pump decreased. For cold climate regions of Russia it is rational to use a bivalent heat pump technology (“air to air” HP + gas boiler installation). The economic efficiency of the bivalent heat pump technology using the “air to air” HP at outdoor air temperatures of -15...-40 оС and -25...-40 оС was defined. Power consumption reduced about 2 times in comparison with the gas boiler installation. The term of payback of the bivalent heat pump technology was 4,4 years according to the economic estimation (using capital investments and energy resources values during period when the estimation was carried out). A technical feasibility as well as energy rationality and economic efficiency of using outdoor temperatures for premises heating were proved. Keywords: “air to air” heat pump, air heating, bivalent heat pump technology, boiler installation, economic efficiency

The paper presents the results of the researches of the fruits and vegetables processing efficiency using ionizing radiation (gammarays, accelerated electrons) to inhibit the phytopathogenic microflora during cold storage in the modified atmosphere in polymeric packages. It is shown that the chosen doses of radiation (1-3 kGy*), packing materials of barrier type (polyamidepolyethylene, 70-80 mm) and storage conditions (4…6 оС) provide 97,7-100% efficiency to inhibit the vital activity of the vegetables microflora (bacteria, moulds and yeast). Thanks to the increase of vegetables respiration after radiation and gas permeability of chosen packages the atmosphere at СО 2 high content (up to 6,5-15%) and О 2 low content (8-12%) is formed. The modified atmosphere together with the radiation impact give the possibility to reduce losses from spoilage and mass decrease of vegetables (carrots, tomatoes, pepper) 3-5 times, to increase the storage life up to 2-3 months at 4...5 оС as well as to keep a high organoleptic and physiologic and biochemical quality of vegetables. Thanks to the antiseptic effect, inhibiting the pathogenic microflora (salmonella, colibacillus, etc.) the technology offered may be considered as a constituent of the conception of the food safety of the Russian Federation. Also the paper deals with other effective ways of optimization of the fruit and vegetable storage using the ionizing radiation (radiation of potatoes and onion to prevent the germination, regulation of the processes of afterharvesting ripening of fruits, etc.). The problems of the radiation processing applied in the countries of the world including the safety of radiation and its using are taken up. Keywords: vegetables processing using ionizing radiation, inhibition of phytopathogenic microflora, cold storage of vegetables, modified atmosphere, package from the material of barrier type