摘要:
The current disclosure relates to steam generation and supply apparati and associated control systems. Particularly, the current disclosure relates to such steam generation supply apparati and associated control systems that are used for enhanced oil recovery. Certain embodiments are provided including methods and associated control systems related to the startup as well as main steam pressure header control or maintenance of a desired steam quality for such steam generation systems during normal operation.
摘要:
The invention relates to a steam generator comprising a heating gas channel, which can be traversed in an approximately horizontal heating gas direction and in which at least one continuous heating surface is located, configured from a number of approximately vertical evaporator tubes, connected in parallel to allow the passage of a flow medium. The aim of the invention is to provide a method for starting a generator, which guarantees a high degree of operational safety, even for a steam generator with a particularly simple construction. According to the invention, to achieve this, at least several evaporator tubes are partially filled to a predeterminable desired level with unevaporated flow medium, prior to the impingement of the heating gas channel by a heating gas.
摘要:
A once-through boiler is provided with integral separators with which drain valves are associated. Boiler inlet and outlet flows are balanced throughout startup first by drain valve control in response to separator level and then by drain valve control in response to throttle pressure.
摘要:
The rate of feedwater flow is controlled in a first load range by the level of water in the separator while in a higher load range the rate is controlled by the steam temperature. Signals are produced which are compared with preset values and are integrated so as to produce a negative control signal in one case and a positive control signal in the other case. Only one of these control signals is superimposed on a base signal only when the generator is in a respective load range so as to produce a command signal for adjusting the feed controller of the feed valve.
摘要:
An improved startup system for a vapor generator of the oncethrough type. The system includes a startup bypass line which leads directly to the tube side of a shell and tube feedwater heater for the generator feedwater circuit, from certain heating passes of the generator main flow circuit; a branch line which leads from the bypass line to the shell side of the heater; and a return line which returns the flow from the heater shell side back to the generator main flow circuit downstream of the bypass line. A pressure reducing valve in the branch line reduces the pressure of the fluid flowing therein lowering its temperature for heat exchange with fluid on the tube side of the heater. The feedwater circuit of the generator includes a bypass around the heater, the generator further having shutoff valves in both the startup system and feedwater circuit for isolating the heater from one or the other of the main flow or feedwater circuits depending upon use of the heater.