A Natural-Convection Promoter for Geothermal Wells

Abstract

Many geothermal wells stand with relatively cold water overlying hot water. If a pipe is inserted into such a well, natural convection will occur and hot water will flow to the top of the well. The convection promoting pipe enable s domestic wells which would normally require the use of a downhole pump or airlift (with attendant environmental problems of fluid disposal) to be satisfactorily operated with a downhole heat exchanger. In potentially powerful steam water wells which are difficult to discharge, a pipe positioned beneath the water level should raise wellhead pressure to the point where spontaneous discharge is possible. In both cases, the permeability and temperature of the feed zones are the limiting factors for the heat output of the well.