Abstract: A new and unique boiler and method of transition between air and Oxy-combustion in a coal fired combustion process wherein near pure oxygen may be introduced to the boiler furnace in several locations including directly into the flame through the burner and/or directly into the furnace as nearly pure oxygen, and/or into the recycle flue gas streams to the burners, including both primary and secondary streams.

Abstract: A new and unique boiler and method of transition between air and Oxy-combustion in a coal fired combustion process wherein near pure oxygen may be introduced to the boiler furnace in several locations including directly into the flame through the burner and/or directly into the furnace as nearly pure oxygen, and/or into the recycle flue gas streams to the burners, including both primary and secondary streams.

Abstract: A pulverizer control system for controlling primary air flow and coal feeder speed to a coal pulverizer comprises a feeder controller for controlling the feeder speed, a feeder speed transmitter for sensing the feeder speed, a primary air flow controller for controlling the primary air flow to the pulverizer and a flow transmitter for sensing the primary air flow. A pulverized coal flow estimator is connected to the transmitters for calculating a coal flow rate which is compared in a first comparator with a demand signal for generating a first error signal. The first error signal is processed in a proportional plus integral unit to obtain a first pulverizer demand signal which is again compared in a second comparator with the calculated coal flow rate to obtain a second demand signal. The second demand signal is utilized to control the feeder controller.

Abstract: A boiler water trip system comprises a flow transmitter for sensing a flow of water into a boiler, a pressure transmitter for sensing a pressure of steam entering a first stage of a turbine powered by the boiler, a unit power transmitter for sensing the power generated by the turbine, a feeder water temperature transmitter and a drum level transmitter for sensing the level of water in a steam drum connected to the boiler. Function generators are connected to the pressure and unit load transmitters for obtaining a measure of flow out of the boiler. The higher of the two flow values are compared with the feed water flow to the boiler to generate an error signal which is integrated. The integrated error signal corresponds to a calculated boiler water level amount. If the boiler water level rises above or falls below set limits and, simultaneously, a drum level rises above or falls below said amounts as determined by the drum level transmitter, a tripper is activated to trip the boiler.

Abstract: A once-through solar steam generator assembly (16) is controlled by a control system wherein the outlet temperature of superheated steam from two independent boiler flow paths (1-12; 1'-12') is independently controlled to a common set point by a combination of water spray attemperation (32) at the primary superheater outlet (34, 36; 34', 36') of each flow path (1-12; 1'-12') and the control of feedwater flow through the independent flow paths (1-12; 1'-12').

Abstract: A once-through solar steam generator assembly (16) is controlled by a control system wherein the outlet temperature of superheated steam from two independent boiler flow paths (1-12; 1'-12') is independently controlled to a common set point by a combination of water spray attemperation (32) at the primary superheater outlet (34, 36; 34', 36') of each flow path (1-12; 1'-12') and the control of feedwater flow through the independent flow paths (1-12; 1'-12').