Ethanol working medium hot dry rock geothermal heat pipe efficient heating system and method

Abstract

The invention discloses an ethanol working medium hot dry rock geothermal heat pipe efficient heating system and method, and relates to the technical field of thermal energy-saving equipment. The system comprises a draught fan, a vacuum pump, an ethanol storage box, a heat exchange chamber, a vacuum pump, a heating box arranged on the ground and a heat pipe vertically buried underground, wherein the two ends of the heat pipe are of a closed structure, the heat pipe comprises a condensation section, a heat preservation section and an evaporation section which are sequentially arranged from topto bottom, the heat preservation section comprises an outer sleeve and a heat insulation inner sleeve, the outer sleeve is connected with the condensation section and the evaporation section separately, the heat insulation inner sleeve serves as an ascending steam channel and is connected with the outer sleeve, and a gap is reserved between the outer sleeve and the heat insulation inner sleeve toserve as a condensate circulation channel. According to the system, ascending steam enters the heat pipe condensation section via the heat insulation inner sleeve, condensed water on the inner wall ofthe heat pipe condensation section enters the evaporation section via the condensed liquid circulation channel, and therefore carrying of descending condensed liquid by the ascending steam is reduced, and resistance of the descending condensed liquid to the ascending steam is reduced.

Description

technical field [0001] The invention relates to the technical field of thermal energy-saving equipment, in particular to a high-efficiency heating system and method for hot dry rock geothermal heat pipes with ethanol working fluid. Background technique [0002] With the rapid development of mechanical drilling technology worldwide, the development of medium-low temperature (within 200°C) hot dry rock geothermal technology within 5 km below the surface has attracted attention in recent years. The current hot dry rock geothermal technology is mainly carried out through two types of technologies. Recovery: one is to inject water into the deep hot dry rock through drilling, and then extract and recycle the hot water or steam heated by the hot dry rock from the deep well, which can be used for power generation, heating and low-temperature drying, etc., but This type of technology needs to recharge a large amount of water, and there is a large amount of water diffusion loss, and t...

AI Technical Summary

Problems solved by technology

[0002] With the rapid development of mechanical drilling technology worldwide, the development of medium-low temperature (within 200°C) hot dry rock geothermal technology within 5 km below the surface has attracted attention in recent years. The current hot dry rock geothermal technology is mainly carried out through two types of technologies. Recovery: one is to inject water into the deep hot dry rock through drilling, and then extract and recycle the hot water or steam heated by the hot dry rock from the deep well, which can be used for power generation, heating and low-temperature drying, etc., but This type of technology needs to recharge a large amount of water, and there is a large amount of water diffusion loss, and the hot water produced has high hardness and serious scaling problems; the other type is the emerging gravity heat pipe technology in recent years. Canned distilled water, and maintain a certain degree of vacuum, can carry the geothermal energy of the deep hot dry rock to the surface, and then use it for heating and heating. Since this technology has no environmental pollution, and its structure is simple, it is not affected by the regional environment. At present, A large number of researchers have proposed to use this technology to heat the area or to dry agricultural products

[0003] But the main problem that exists at present is that for this long-distance gravity heat pipe technology, at present, water is used as the working medium, and a plurality of short pipes are connected. It is necessary to vacuumize the heat pipes to work effectively. There is a certain gap at the connection, so there is an inflow of non-condensable gas, such as air, during use, and the existence of non-condensable gas in the heat pipe will seriously affect the heat exchange between the evaporation section and the condensation section of the heat pipe. Due to the low density of water vapor Due to the air density, the non-condensable gas mainly gathers in the evaporation section of the heat pipe, and this part is located in the deep underground. The conventional method of directly evacuating from the surface near the surface has a poor removal effect on the non-condensable gas.

Therefore, the hot water type gravity long-distance heat pipe currently used has the disadvantages of fast load drop, short vacuum interval, and large amount of distilled water replenishment during use.

Images