Abstract: A method for operating a directly heated, solar-thermal steam generator is provided. As per the method, a nominal value {dot over (M)}s for the supply water mass flow {dot over (M)} is conducted to an apparatus for adjusting the supply water mass flow {dot over (M)} wherein, at the adjustment of the nominal value {dot over (M)}s for the supply water mass flow {dot over (M)}, account is taken of a correction value KT, by which the thermal effects of storage or withdrawal of thermal energy in an evaporator are corrected.

Abstract: A method for operating a once-through steam generator including an evaporator heating surface is provided. A target value for the supply water mass flow is fed to a device for setting the supply water mass flow, which is predefined using the ratio of the heat flow currently being transferred in the evaporator heating surface from the hot gas to the flow medium to a target enthalpy increase predefined with respect to the desired live steam condition of the flow medium in the evaporator heating surface. A forced-flow steam generator used for carrying out the method is also provided. The heat flow transferred from the hot gas to the flow medium is ascertained for this purpose allowing for a specific temperature value characteristic of the current temperature of the hot gas at the evaporator inlet and a specific mass flow value characteristic for the current mass flow of the hot gas.

Abstract: A method for operating a gas and steam turbine plant is provided. In the plant, the flue gas that escapes from a gas turbine is routed through a waste gas steam generator and where a flow medium that is used to drive a steam turbine is conducted in a flow medium circuit that includes several pressure stages. At least one of the pressure stages has an evaporator circuit with a steam collection drum that has a plurality of downpipes connected to the steam collection drum and a plurality of rising pipes downstream of the downpipes that are likewise connected to the steam collection drum and are heated by the flue gas in the waste heat steam generator. The height of the fluid column formed by the flow medium in the downpipes is monitored and a transient dry operation of the evaporator circuit can thus be detected and safeguarded against.

Abstract: A combined cycle gas turbine plant and a corresponding method for operating such a combined cycle gas turbine plant, in which, during load operation of the combined cycle gas turbine plant, a water mass flow which is supplied according to the forced-flow principle to a waste heat steam generator is adjusted such that the evaporator heating surface of the medium pressure stage is oversupplied and thus a defined amount of excess water, which is heated in the evaporator heating surface but not vaporized, is discharged via the water-steam separator to a heat exchanger circuit for preheating fuel for the gas turbine.

Abstract: A method of controlling a spot welding system used for attaching an inserted element in a hollow member is provided. A position of the inserted element in the hollow member is determined, the position of an attachment point is determined from the position of the inserted element in the hollow member, and a spot welding operation is performed at the attachment point. Further, a spot welding system for carrying out the method is provided.

Abstract: An operating method for an externally heated once-through steam generator, in particular a once-through steam generator is heated using solar thermal energy and has a steam turbine connected downstream of the once-through steam generator. A pressure regulation device, having at least one turbine valve for regulating the pressure, is arranged in the feed water-steam circuit between the once-through steam generator and the steam turbine, the pressure regulation device being controlled by a control unit in such a way that, in the event of sudden load reductions, the drop in pressure associated therewith occurs, in a time delayed manner, by throttling of the at least one turbine valve.

Abstract: An operating method for starting a once-through steam generator heated using solar thermal energy, wherein a flow medium flowing through the once-through steam generator is evaporated and superheated, using a heat carrier medium heated in a solar array, for a steam turbine connected downstream of the once-through steam generator on the flow medium side. In an operating phase under load, a first desired steady pressure value is predetermined, and in a starting phase preceding the operating phase under load, a second desired steady pressure value is predetermined, in which starting phase evaporated flow medium is diverted around the steam turbine via a steam bypass, and controlled by the predetermined second desired steady pressure value.

Abstract: A catalytic exhaust gas purification device and method for the reduction of nitrogen oxides from an exhaust gas of a fossil-fired power plant, having a heating gas duct along a flow direction and having a reactor chamber which is arranged in the heating gas duct is provided. In the reactor chamber there are arranged a first reduction reactor for the reduction of nitrogen oxides NOx to form water H2O and nitrogen N2, an oxidation reactor, which is connected downstream of the first reduction reactor in the flow direction, for the oxidation of nitrogen monoxide NO to form nitrogen dioxide NO2, and a second reduction reactor, which is connected downstream of the oxidation reactor in the flow direction, for the reduction of nitrogen oxides NOx to form water H2O and nitrogen N2. A reduction of nitrogen oxides NOx from an exhaust gas of a fossil-fired power plant is achieved.

Abstract: A once-through steam generator includes a combustion chamber, the walls of which comprise vertically arranged evaporator pipes connected to one another in gas-tight fashion by pipe webs, through which evaporator pipes flows a flow medium from bottom to top. The evaporator pipes are combined by upstream inlet collectors to form more intensely and less intensely heated pipe groups. A feed water supply is assigned to respective inlet collectors. At least one regulating valve regulates throttling of the mass flow of the flow medium into the evaporator pipes. To determine a control variable for the regulating valve, temperature measurement device measures outlet temperatures of the flow medium exiting the evaporator pipes. Each of the more intensely and less intensely heated pipe groups is assigned to one of the inlet collectors and to an outlet collector, and each of the outlet collectors has one of the temperature measurement devices.

Abstract: A forced-flow steam generator includes first and second steam generator pipes which form a surrounding wall, wherein the first and second steam generator pipes are welded in a gas-tight fashion and are traversable by flow in a vertical direction. A passage collector is arranged within the surrounding wall, wherein the passage collector connects the first steam generator pipes with the second steam generator pipes. The first steam generator pipes are connected at an outlet side to an inlet side of the second steam generator pipes, wherein the second steam generator pipes are connected in series with the first steam generator pipes. Each of the second generator pipes has a restrictor device. Further, a power plant with a forced-flow steam generator is provided.

Abstract: A method for operating a continuous flow steam generator with an evaporator heating surface is provided. A target value for a supply water mass flow is fed to a device for adjusting the supply water mass flow. In order to improve the quality of a predictive supply water or mass flow control and to maintain the enthalpy of the flow medium at the evaporator outlet particularly stable especially when load changes occur, a correction factor is taken into consideration during production of the target value for the supply water mass flow. The correction factor is a characteristic of the temporal derivative of enthalpy or the density of the flow medium at the input of one or more heating surfaces.

Abstract: A continuous steam generator including a combustion chamber with a plurality of burners for fossil fuel is provided. A vertical gas duct is connected downstream of the combustion chamber on the hot gas side, in an upper region via a horizontal gas duct. The outside wall of the combustion chamber is formed from evaporation pipes which are welded together in a gas-tight manner and mounted upstream of a water separator system on the flow medium side and from superheater pipes which are welded together in a gas-tight manner and mounted downstream of the water separator system. The water separator system includes a plurality of water separation elements, each element includes an inlet tube which is connected to the respective upstream evaporation for tubes, which extend into a water evacuation tube. A distributer element is arranged on the evaporator side between the respective water separator element and the inlet collector.

Abstract: A method for flexible operation of a power plant having a recovery steam generator having heat exchanger stages for generating live steam and/or reheater steam for a steam turbine from an exhaust flow of a gas turbine, wherein auxiliary firing is arranged in a flue gas channel of the recovery steam generator in the region of the heat exchanger stages. In order to regulate the live steam and/or the reheater steam, at least one injection cooling device is brought online directly upon using the auxiliary firing.

Abstract: A method of operating a combined gas and steam turbine system is provided. The system includes a gas turbine, a waste heat steam generator with an evaporator heating area, and a steam turbine. Fluid is fed to the waste heat steam generator as feed water. A primary control loop controls a feed water flow rate. Taking into account heat stored in the evaporator heating area, a primary desired value for the feed water flow rate is determined based upon a desired overheating value characteristic of a temperature by which the fluid exceeds a boiling point as the fluid exits the evaporator heating area and based upon a heat flow parameter characteristic of a heat flow transfer from fuel gas to the fluid via the evaporator heating area. The desired overheating value is lowered from a first value to a second value in order to activate an instantaneous power reserve.

Abstract: A catalytic exhaust gas purification device and method for the reduction of nitrogen oxides from an exhaust gas of a fossil-fired power plant, having a heating gas duct along a flow direction and having a reactor chamber which is arranged in the heating gas duct is provided. In the reactor chamber there are arranged a first reduction reactor for the reduction of nitrogen oxides NOx to form water H2O and nitrogen N2, an oxidation reactor, which is connected downstream of the first reduction reactor in the flow direction, for the oxidation of nitrogen monoxide NO to form nitrogen dioxide N02, and a second reduction reactor, which is connected downstream of the oxidation reactor in the flow direction, for the reduction of nitrogen oxides NOx to form water H2O and nitrogen N2. A reduction of nitrogen oxides NOx from an exhaust gas of a fossil-fired power plant is achieved.

Abstract: A resistance point welding apparatus for fixing a turbulence installation body to an inner wall of a steam generator pipe, having a welding head, which is introduced into the pipe and includes a lance having an electrically conductive material, a point welding electrode, which projects out of the lance in the radial direction, an effective element and an insulation body, which is opposite the point welding electrode in the radial direction and is moved by the effective element, is provided. The lance is tapered at a defined distance from the welding head end such that the insulation body and the point welding electrode press the turbulence installation body against the inner wall of the pipe when the effective element is activated. When a welding stream is impressed on the lance, a point-like welding stream flows via the point welding electrode to a counter electrode arranged outside the pipe.

Abstract: A method for flexibly operating a nuclear power plant with a waste heat steam generator that operates according to the forced-flow principle and that has heating surfaces of different stages of the waste heat steam generator, the heating surfaces being arranged in the flue gas channel, is provided. In order to increase the output, a mass flow of the feedwater flowing through the heating surfaces is increased while almost simultaneously activating a supplementary firing arranged in the flue gas channel of the waste heat steam generator.

Abstract: An alkali-chalcogen battery that includes a cathode that includes at least one of at least one chalcogen and at least one alkali-chalcogen compound, and an anode. At least one of an alkali metal-containing liquid electrolyte, gel electrolyte and solid electrolyte is disposed between the anode and the cathode. Also, a cation-selective separator is disposed at least in regions between the anode and the cathode, the separator being permeable for alkali metal ions and impermeable for polychalcogenide ions (Zn2? with n?2, Z representing the chalcogen), and the separator having a maximum layer thickness of 30 ?m.

Abstract: A Li—S battery including a cathode and an anode and at least one of a lithium-containing liquid electrolyte, gel electrolyte, and solid electrolyte disposed between the cathode and the anode. The cathode includes at least one of an electrically conductive carbon material, an electrochemically active cathode material that comprises sulphur, and at least partially fibrillar plastic material. The anode includes a conducting substrate which is coated at least in regions with at least one of silicon and tin. A method for operation thereof.

Abstract: A method is provided for regulating a brief increase in power of a steam turbine that has an upstream fossil-fired once-through steam generator having a plurality of economizer, evaporator and superheater heating surfaces which form a flow path and through which a flow medium flows. The flow of the flow medium through the fossil-fired once-through steam generator is increased in order to achieve the brief increase in power of the steam turbine. The method involves using desired enthalpy value at the outlet of an evaporator heating surface as a control variable for determining a desired value for the flow of the flow medium through the fossil-fired once-through steam generator. The desired enthalpy value is reduced in order to achieve the brief increase in power of the steam turbine.