Abstract: A pressure atomizing liquid fuel burner having an improved turndown ratio is disclosed along with a method of increasing the turndown ratio in such burners. The burner includes means for adding an amount of gas to the liquid fuel prior to the injection of the fuel which causes the liquid fuel to foam such that a liquid-gas foamed mixture is injected. The relative amounts of the aeration gas and the liquid fuel are controlled such that the injection velocity is maintained relatively constant over a wide turndown ratio in the liquid fuel. The aeration gas to be added to the liquid fuel may be preheated prior to the addition of the gas to the liquid fuel.

Abstract: A method of low temperature energy storage and utilization is disclosed which can be used in conjunction with low temperature heat sources such as solar energy flat plate collectors. Input heat energy is utilized to sustain the endothermic dissociation of ammonium carbamate produced from a reaction between urea and water. The energy is retained in the form of the higher energy containing dissociation products ammonia and carbon dioxide. The dissociation products are separated by liquifying and draining off the ammonia and are held under pressure. The stored heat is extracted in the form of output heat energy for an end use by reversing the dissociation reaction and combining the ammonia and carbon dioxide to form ammonium carbamate which becomes urea and water and is recirculated as a slurry. Closed-loop, fluid-medium heat exchange systems can be used both in the input and output sides of the energy system. The entire system operates at temperatures of less than 250.degree. C.