Abstract: Improved production of pig iron is effected with lump lignite or sub-bituminous coal that have been heated in hot water or steam under elevated pressure sufficient so that water does not change into steam. High moisture content lignite and sub-bituminous coal, which normally cannot be used in blast furnaces because of slacking, are partially dried by this treatment. For example, lumps of lignite or sub-bituminous coal with moisture contents of 30% to over 50%, have the moisture content reduced to from about 15% to 25% by this treatment and shrink in size and become much harder so that they do not slack and can be used in conventional lump size in blast furnaces. The temperature of heating with water or steam is preferably about 210.degree. C to 218.degree. C. The blast furnace is preferably operated with oxygen and steam though preheated air may be used.

Abstract: Comminuted iron ore, which may be pre-reduced partly or wholly if desired, is flash smelted in a vertical shaft furnace with excess carbon, and off gases are produced from which a large amount of hydrogen is recovered. The major portion of hydrogen is a product gas which can be used for reactions, such as the production of ammonia, hydrogenation of coal, and the like, or it may be used as a cooling agent for electric generators and the like.

Abstract: A refrigeration system in which refrigerant liquid is cooled by self-evaporation and is used for refrigerating in the liquid form, in which the self-evaporation is in stages, each having a vapor compressor, the expansion taking place in enthalpy converting liquid turbines instead of permitting partial vaporization through valves into vapor separators. The enthalpy converting liquid turbines are much more efficient than the adiabatic liquid expansion which is customarily used in refrigeration systems in which a cold liquid cooled by the expansion is evaporated to absorb heat and thus to provide cooling. There is much less irreversibility and hence increase in entropy is reduced, especially when removal of super heat from the compressed vapors in each stage is effected by quenching with a small portion of the refrigerant liquid. A good portion of this heat is recovered as mechanical energy in the enthalpy converting turbines.

Abstract: Waste heat in the form of the sensible heat of flue gases, sensible and latent heat of geothermal sources, etc., is converted to usable energy. When the energy source consists solely of sensible heat of a gas or a liquid which is not the working fluid, the liquid working fluid is heated by the energy source and then expanded in a hot liquid turbine wherein partial vaporization occurs with decrease in pressure. The working fluid is thereby accelerated as thermal energy is converted to kinetic energy and internal energy of the vapor. The hot liquid turbine can be a hot liquid impulse turbine wherein the expansion occurs in the inlet nozzles and the mixed phase working fluid then impinges on the moving buckets of the impulse turbine transferring the kinetic energy to shaft work.