Abstract: An apparatus for heat recovery from an exhaust gas with waste heat from a heat machinery unit, which comprises a pair of first and second chemical heat-storing units, each comprising a vessel containing a reactant material capable of releasing a reaction-susceptible material upon heating with an exhaust gas and emitting the heat of reaction upon combination with the reaction-susceptible material and a heat exchanger piping provided in the vessel and through which a heat transfer medium is passed. The high temperature gas from the heat machinery unit is applied to the vessel in one of the first and second chemical heat-storing units, thereby resulting in a reaction for leasing the reaction-susceptible material.

Abstract: A waste heat recovery boiler for a turbine including two denitrating devices disposed in the boiler to reduce the NOx concentration in an exhaust gas below a pre-determined value even when a turbine load changes. The overall denitration efficiency distribution of the boiler with respect to the turbine load can be set arbitrarily by selecting suitable positions of the denitrating devices and the amounts of a catalyst, and any adverse effects resulting from the change of the turbine load can be avoided.

Abstract: A method of operating a combined plant made up of a gas turbine plant and a steam turbine plant utilizing the exhaust heat of the gas turbine as its power source; in which, after the steam turbine has been stopped and before it is started, the gas turbine is kept running at a low constant load for a certain period of time with the exhaust gas from the gas turbine being led partly to a by-pass duct and partly to a heat recovery boiler, during which time necessary operations to start or stop the combined plant (such as breaking the vacuum in the condenser) are performed.

Abstract: In starting a steam turbine plant of a combined plant including a gas turbine plant in addition to the steam turbine plant, a condensation system is controlled in such a manner that water retained in a deaerated water tank used in the steam turbine plant is fed to a gas turbine waste heat recovery boiler at steam turbine plant start-up, and the condensate recovered from the boiler is stored in a condenser and a condensate tank. Feeding of water from the condenser to a deaerator is initiated when the deaerator functions satisfactorily by using as a heat source the water at the outlet of a fuel economizer of the boiler.

Abstract: In shutting down a combined power plant, a steam turbine is first shutdown while operation of a gas turbine at high load is being continued, and the steam generated in a waste heat recovery boiler is passed on to a condenser through a bypass system bypassing the steam turbine. The gas turbine is then shutdown when this condition prevails, and gland sections of the steam turbine receive a supply of gland sealing steam which has been heated by a heater to a temperature level close to that of the steam attained while the steam turbine is in operation, thereby to maintain the temperature of the metal of the steam turbine gland sections at a desired level during the time the steam and gas turbines are shutdown. In restarting the combined plant, the gas turbine is first started and then the steam turbine is started.