Research on the issue of using the heat of combustion products for heat supply of greenhouses

State Energy Institute of Turkmenistan, st Bayramhan 62, c. Mary 745400, Turkmenistan

^* Corresponding author: marytdei@mail.ru

Abstract

Cultivation of agricultural crops in winter season is carried out in special greenhouses. For heating greenhouses, a huge amount of heat energy is consumed. In the conditions of Turkmenistan, up to 1500 tons of standard fuel per year is consumed to heat the greenhouse with an area 1 hectare. The increase in heating costs leads to an increase in the prices of grown products. Therefore, saving fuel energy in the greenhouses is one of the most important economic factors. Possibilities of using the heat of the combustion products of steam boilers at the Mary State Electric Power Station (Turkmenistan) for heating greenhouses are discussed in the article. For this purpose, a special contact heat exchanger is installed on the line of the outgoing combustion products of steam boilers. In the experimental facilities, water is injected from top to bottom, and combustion products move in the opposite direction. In this case, the temperature of the combustion products decreases from 120-150 °C to 30-40 °C. The temperature of the cooling water of the combustion products rises from 10-20 °C to 40-45 °C. To increase the contact surface of water and gas in a contact heat exchanger, spray-type layer conductor is used. A distinctive feature of the experimental facility is the use of local materials as a spray-type layer with a conductor. For subsoil heating of greenhouses, water is supplied with the temperature of 40 °C, and for the raise of the vegetables grown in them water is supplied with the temperature of 22-25 °C. The use of the heat of combustion products to heat greenhouses is of great importance both for saving fuel and for purifying the environment from harmful emissions.