481results about "Superheating control" patented technology

The invention provides an energy storage coupling heat pump heat supply system and a heat supply method. The system comprises a heat pump device, an energy storage device and a control module. The heat pump device heats the heat carrier to a first temperature, and the energy storage device further heats the heat carrier to a second temperature for heat supply. The control module dynamically regulates and controls operation of the heat pump device and the energy storage device according to the heat supply demand quantity and the external heat source state, the heat pump device and the energy storage device are preferentially operated in the off-peak electricity period to complete heat storage, and first enthalpy increment provided by the heat pump device and second enthalpy increment released by the energy storage device are dynamically distributed in the heat supply period. And diversified thermal load requirements are met. The system supports real-time adjustment of power distribution, preheating optimization and waste heat utilization, and has the characteristics of high efficiency, flexibility and energy conservation.

The invention discloses a coal-fired unit main steam temperature control method based on feed water flow asynchronous regulation, which comprises the following steps of: firstly, calculating the variation of total heat carried by a boiler drum inlet working medium corresponding to unit feed water flow change, and further calculating the variation of saturated steam flow generated by a drum according to energy balance; therefore, the main steam temperature change value corresponding to the change of the unit feed water flow is obtained, then the feed-forward quantity of the main steam temperature deviation on the regulation of the feed water flow of the boiler system is obtained in combination with the real-time deviation of the main steam temperature, and asynchronous regulation of the feed water flow is realized. According to the method, the control effect of the main steam temperature can be greatly improved, and the method is of great significance to improvement of the rapid load changing capacity of the coal-fired unit.

This invention discloses a supercritical carbon dioxide cycle generator set water spray desuperheating system, comprising a supercritical carbon dioxide cycle power generation system and a water spray desuperheating system; the supercritical carbon dioxide cycle power generation system includes a heater, a screen-type superheater, a final-stage superheater, and a turbine; the water spray desuperheating system includes a first desuperheating water injection point, a second desuperheating water injection point, and a liquid-water separation system; the heater outlet is sequentially connected to the turbine inlet via the first desuperheating water injection point, the screen-type superheater, the second desuperheating water injection point, and the final-stage superheater; the turbine outlet is connected to the inlet of the liquid-water separation system; the liquid outlet of the liquid-water separation system is connected to the first and second desuperheating water injection points; and the gas outlet of the liquid-water separation system is connected to the heater inlet. This system can solve various problems caused by carbon dioxide desuperheating.

The embodiment of the invention provides a cascade heating superheated steam generation system and a control method thereof, and belongs to the technical field of energy engineering and thermal power. The system comprises: an evaporation device provided with a plurality of heat exchangers, wherein the evaporation device is used for treating preheated produced water into wet saturated steam; wherein the series-parallel connection relation between the heat exchangers in the evaporation device is adjusted based on real-time heat supply demand information; the steam conversion device is used for converting the wet saturated steam into superheated steam for steam injection; the control device is used for determining the serial numbers of the heat exchangers participating in heat exchange and the series-parallel connection relation of the heat exchangers participating in heat exchange based on the real-time heat supply demand information; the fused salt conveying device sequentially passes through the steam conversion device and the evaporation device and is used for providing a heat source for the steam conversion device and the evaporation device. According to the scheme, the method adapts to complex heat supply demand scenes, and therefore an efficient, flexible and intelligent solution is provided for thick oil steam injection.

The utility model relates to the technical field of waste heat recovery of thermal power plants, and discloses a temperature and pressure reducing stable heat supply device which comprises a conveying pipe and a steam pipe, the steam pipe is fixedly installed on the inner wall of the conveying pipe, a plurality of sets of steam spray holes are formed in the steam pipe, and the steam spray holes are communicated with the conveying pipe. A water tank is fixedly installed on the outer wall of the conveying pipe, a water pump is fixedly installed on the outer wall of the water tank, the water pumping end of the water pump communicates with the interior of the water tank, a connecting pipe is fixedly installed at the water drainage end of the water pump, and the end, away from the water pump, of the connecting pipe penetrates through the conveying pipe and is fixedly provided with an annular pipe. High-pressure steam sprayed out of the steam pipe through the steam spraying holes can impact the impeller, then the impeller drives the sleeve to rotate, water mist sprayed out of the atomization spray head can be scattered through rotation of the sleeve in cooperation with the rotating shaft and the spoiler, the coverage range of the water mist is expanded, and the temperature reduction effect of the water mist on high-heat and high-pressure steam is improved.

The invention provides a heat exchange control system and method applied to a thermal inertia tube bundle, and relates to the field of heat exchange. Under the condition that the target heat exchange requirement exists, the main pipeline valve is closed, the inflow control valve and the outflow control valve are opened, and the heat conduction particles output by the particle output device are mixed with the working medium to obtain particle suspension liquid; due to the fact that the heat conduction coefficient of the heat conduction particles is larger than that of the working medium flowing into the inflow bypass pipeline, the heat conduction coefficient of particle suspension liquid obtained after the heat conduction particles and the working medium are mixed is larger than that of the working medium. And heat exchange between the working medium and the inner wall surface of the thermal inertia tube bundle during rapid load change is enhanced, and the working medium heat exchange rate is increased when the working medium is under-temperature, so that the working medium can reach the required temperature, the heat exchange accuracy is improved, and safe operation of subsequent equipment is guaranteed.

The invention discloses a thermal power generating unit main reheating steam temperature wide-load self-adaptive adjusting method and system, relates to the technical field of electric power industry automation and control, and aims at solving the problems that an existing adjusting method is large in steam temperature fluctuation, high in thermal stress and poor in main reheating collaboration under the wide-load working condition. The method comprises the steps of calculating main steam phase saturation and mapping a target value; calculating the maximum change rate based on the thermal physical parameters of the material, and generating a reference track with the limited change rate; the steam phase saturation of the main steam is used as a phase reference, and the reheated steam is controlled to respond according to a preset phase difference; a combustion system, a flue gas temperature adjusting baffle and a temperature reducing water system are cooperatively controlled; the system comprises a vapor phase saturation processing module, a dynamic boundary generation module, a phase coordination control module, an execution mechanism coordination module, a steady state detection module and a mode switching module. Accurate steam temperature adjustment under the wide load is achieved, material thermal stress is reduced, unit operation safety and economical efficiency are improved, and the variable-load operation requirement of the unit is met.

The utility model discloses a desuperheater, and belongs to the technical field of steam temperature control. The desuperheater comprises a desuperheating pipeline, a hot steam inlet, a desuperheating water inlet, a swirler and a proper-temperature steam outlet, the swirler is provided with a plurality of swirling vanes, the swirling vanes are arranged in the circumferential direction of the desuperheating pipeline by a circle, and the proper-temperature steam outlet is formed in the circumferential direction of the desuperheating pipeline. The radial outer ends of the rotational flow blades abut against the inner wall of the temperature reduction pipeline, and seen from the axial direction of the temperature reduction pipeline, the side edge of each rotational flow blade is completely located in front of or behind the blade face of the adjacent rotational flow blade. And the parallel projection of the swirler in the axial direction of the temperature reducing pipeline is fully distributed on the cross section of the temperature reducing pipeline. Through the arrangement, the desuperheater is beneficial to full mixing of superheated steam and desuperheating water, and the purposes of rapidly cooling and shortening the desuperheating distance are achieved.

The invention discloses a deep peak regulation and frequency modulation heat energy storage system and method coupled with a coal-fired unit, and belongs to the technical field of coal-fired unit flexible transformation and power grid regulation. Aiming at the problems that a single fused salt / solid heat storage occupies a large area, the initial investment is high, a steam generation system is complicated, and a conventional coal-fired unit is difficult to meet the requirements that the minimum power generation output of a new generation coal-electricity pilot demonstration unit is less than or equal to 20% Pe, and deep peak regulation is realized to give consideration to primary frequency modulation performance through self or auxiliary regulation as much as possible in the specification of power generation and transformation energy (2025) 363. The system comprises a heat energy storage unit and a coal-fired unit, the heat energy storage unit comprises a demineralized water supply water tank, an electrode steam boiler, a spherical tank and a heat storage type steam temperature increasing device, and the structure of spherical tank flash evaporation steam supply and heat storage temperature increasing sensible heat supplementing is adopted to be matched with steam supplementing of a steam turbine. The combined minimum power generation output of the two can be reduced to 10% Pe, the peak increase output is at least 5.6% Pe, primary frequency modulation is assisted by increasing and decreasing the power consumption of the electrode steam boiler, and new energy consumption is assisted.

The invention discloses an implementation method of a single auxiliary machine steam pump RB of a circulating fluidized bed unit, which comprises the following steps: after the steam pump trips, the action condition of the steam pump RB: opening a front electric door and a rear electric door of a boiler water supply bypass adjusting door when the RB acts; when the RB acts, the current of the electric pump is 200A and the outlet pressure of the electric pump is more than 20MPa, an outlet regulating valve of the electric pump is opened to 35%; coordinating to a turbine following TF mode, and forcibly switching a unit operation mode to a sliding pressure mode; after RB occurs, AGC is automatically cut off, meanwhile, an instruction is sent to a DEH system, and a sequence valve is cut into a single valve; and when the load of the unit is reduced to the target load for 3 seconds or the operator presses down a steam pump RB ending button, the RB process is ended. The system has the advantages that after the single steam pump trips, the unit load is changed to the target load without manual intervention of an operator, so that the operation intensity of the operator in an accident state is greatly reduced, and the probability of misoperation of the operator is reduced; the load range of a boiler BT is increased from 80MW to 160MW when a steam pump trips out, so that a larger safe and stable operation space is provided for a unit; bT accidents are avoided, and the purpose of saving coal consumption is achieved.

The invention provides an ultra-supercritical boiler full-working-condition composite dry-wet state conversion system and method, and belongs to the technical field of coal power unit flexible transformation. The method comprises the steps that in the initial stage of starting of a coal power unit, a coal-fired boiler is in a wet state, and the coal-fired boiler is in a wet state; the wet water separated by the separator is recycled based on a boiler water recycling module and a drainage capacity expansion module; when the operation load of the coal-fired boiler ranges from the first preset load to the second preset load, the water level of a water storage tank of the boiler is controlled based on the boiler water recycling module, and a pipeline of the drainage expansion module is heated through wet water; when the second preset load reaches the third preset load, the boiler water recirculation module is closed, the drain capacity expansion module and the heat exchange deoxidization module are started, and the water level of the water storage tank is finely adjusted; and when the load is larger than the third preset load, the coal-fired boiler is switched into dry-state operation, and the drainage capacity expansion module and the heat exchange deoxidization module are closed. The working medium and heat of circulating water in the coal-fired boiler starting stage and the deep peak load regulation load can be recycled.

The invention discloses a steam temperature control method for a tower type solar photo-thermal power station, which fuses the control of a hot molten salt delivery pump and the control of inlet hot molten salt regulating valves of a superheater and a reheater according to the control characteristics of a regulating loop so as to effectively relieve the influence of temperature lag. Compared with the prior art, the method provided by the invention is based on an independent and decoupled operation mode of a superheated steam and reheated steam temperature adjusting loop so as to efficiently respond to the requirement of power change of the steam turbine generator unit. Meanwhile, the operation state and the change trend of the superheated steam temperature adjusting loop and the reheated steam temperature adjusting loop can adjust the operation of the hot salt pump flow adjusting loop. In order to organically coordinate the mutual relation, a control method based on the valve position of a regulating valve and the deviation characteristic of a control loop is set, and the valve position relation characteristic of the regulating valve in the superheated steam and reheated steam temperature regulating loop and the deviation state and trend information of the regulating loop are introduced into a combined valve position integrator and a combined monitor; operation of the hot salt pump flow adjusting loop is adjusted in real time through monitoring and judgment of the two.

The invention discloses a Venturi type steam rotational flow atomization desuperheater and a regulation and control system, and belongs to the technical field of steam temperature and pressure reduction. The problems that in an existing desuperheater, desuperheating water makes direct contact with a high-temperature barrel, the local temperature difference of the barrel is obviously increased, and cracks or deformation is likely to be generated due to thermal stress in long-term operation are solved. A venturi structure is applied to the desuperheater, a steam inlet pipeline, an inlet conical pipe section, a venturi throat pipe section, an outlet conical pipe section and an outlet pipeline are arranged in the desuperheater, and steam sequentially passes through the structure. And a sawtooth rotational flow channel is arranged on the inner wall of the venturi throat pipe section. The conical pipe section is provided with water spraying holes, the sleeve is fixed outside the throat pipe section, and desuperheating water enters the steam flow channel through the sleeve and the water spraying holes. And the regulation and control system realizes automatic regulation of the flow of desuperheating water. The desuperheating water is uniformly atomized under the impact action of the rotational flow steam, and liquid drops rapidly absorb heat and are evaporated into low-temperature steam, so that a proper desuperheating and decompressing effect is achieved, and the direct contact between the desuperheating water and the high-temperature cylinder is effectively reduced.

The invention discloses a turbine-boiler coupling flexible heat regeneration method for deep peak regulation, and relates to the technical field of thermal power plant unit steam deep peak regulation. Comprising the steps that boiler fuel supply and combustion intensity are reduced, and a unit enters a low-load operation state; extracting part of high-temperature and high-pressure steam from a main steam pipeline in front of a steam turbine as a heat source; the pressure of the extracted high-temperature and high-pressure steam is reduced through a temperature and pressure reducing device, and water is sprayed for cooling; steam is introduced into the heat exchanger to release heat, primary air and secondary air are heated, and air needed by combustion is preheated through steam waste heat; the steam subjected to air heating exchanges heat with feed water through a first high-pressure heater; the amount of high-temperature and high-pressure steam extracted from a main steam pipeline in front of a steam turbine is adjusted, the load and the system efficiency are balanced, the steam distribution proportion and parameter setting are optimized, and deep peak regulation is achieved. Steam waste heat is comprehensively utilized to increase the air temperature, energy waste during peak regulation is reduced, and the overall efficiency of the system is improved.

The invention provides a superheated steam temperature control method and system for a secondary reheating unit, and belongs to the field of thermotechnical automation, and the method comprises the following steps: obtaining a leading zone superheated steam temperature and an inert zone superheated steam temperature of a three-stage superheater of the secondary reheating unit; the cascade control system of the secondary reheating unit comprising a main loop and an auxiliary loop is designed, a stepped predictive controller SGPC is adopted as a main loop controller of the cascade control system, the stepped predictive controller SGPC is adopted as the main loop controller of the cascade control system, control parameters of the main loop are adjusted through the main loop controller, and the control parameters of the auxiliary loop are adjusted through the auxiliary loop controller. The problems of large delay and large inertia of the system can be solved; by adopting the ADRC as the auxiliary loop controller of the cascade control system and adjusting the control parameters of the auxiliary loop, the secondary disturbance in the auxiliary loop can be inhibited, and the influence of the secondary disturbance on the control of the superheated steam temperature is reduced, so that the superheated steam temperature is controlled within a set range.

The invention relates to an adjustable double-flow water-cooled wall system, a once-through boiler and a generator set, the water-cooled wall system comprises a hearth water-cooled wall, an economizer and a shunting water-cooled wall device, and the shunting water-cooled wall device is provided with a shunting water-cooled wall inlet header and a shunting water-cooled wall outlet header; the shunt water-cooled wall inlet header is connected with a shunt water-cooled wall inlet pipeline, and the shunt water-cooled wall outlet header is connected with a shunt water-cooled wall outlet pipeline; the economizer outlet pipeline comprises a first branch pipeline and a second branch pipeline, the first branch pipeline is connected with the hearth water-cooled wall inlet pipeline, and the second branch pipeline is connected with the shunting water-cooled wall inlet pipeline. The system can greatly improve the hydrodynamic safety of the water cooling wall of the boiler in an ultra-low load interval, meanwhile, the flow resistance of the water cooling wall under full load is not increased, and the operation economical efficiency of the whole unit is not reduced.

According to the energy-saving air-conditioning system with the cold and heat sources provided by the steam waste heat and the operation method, first process equipment of the system serves as medium / high-pressure gas utilization equipment, and medium / high-pressure saturated steam is used for heating; the temperature and pressure reduction device adjusts the steam source to a saturated state, temperature reduction water of the temperature and pressure reduction device is provided by a second steam condensation water tank or a plant desalting water tank of the plant, and saturated steam after temperature and pressure reduction is conveyed to the first process equipment through a second steam pipeline; the flash tank receives and separates steam and condensate water generated by flash evaporation after steam heat exchange of the first process equipment; the steam header is used for receiving steam of the flash tank and low-pressure steam of a plant area and supplying steam to the second process equipment, the steam type lithium bromide absorption refrigerating unit and the combined air conditioning unit; the steam type lithium bromide absorption refrigerating unit provides cold water for the combined air conditioning unit in summer; and the DCS control equipment controls and monitors system operation parameters. The problems that the utilization rate of low-grade heat energy of steam and condensate water of industrial factories is low, and heat energy is wasted are solved.

The invention relates to the technical field of energy utilization and energy storage, and discloses a steam generation system and a pressure cascade early warning regulation and control method thereof, and the system comprises a heat pump device, a water storage device, an energy storage device and a desuperheater; a water feeding pump set and a mother pipe adjusting valve set are arranged on a main water inlet pipeline connecting the energy storage device and the water storage device, and the mother pipe adjusting valve set is used for conducting PID adjustment on the flow of high-temperature water according to pressure data collected by pressure monitoring points arranged in a system pipeline so as to keep the pressure of a steam pipeline stable. A desuperheating water adjusting valve is arranged on a desuperheating water pipeline connecting the water storage device and the desuperheater, and the desuperheating water adjusting valve is used for conducting PID adjustment on the flow of desuperheating water according to temperature data collected by a temperature monitoring point arranged in a system pipeline so as to keep the steam temperature stable. According to the method, adjustment is conducted in the system generation process by combining system water supply amount adjustment and circulation pipeline design, energy is more effectively utilized, and system safety is protected.

The invention provides a peak regulation power generation system and method coupling fused salt heat storage and steam supplementing of a steam turbine, and relates to the technical field of heat energy engineering.The system comprises a fused salt heat storage and heat exchange system comprising a low-temperature fused salt tank, a fused salt heater, a high-temperature fused salt tank and a fused salt steam-water heat exchanger; comprising a gas-fired boiler, a steam turbine and a water supply system; the fused salt heater is used for receiving low-temperature fused salt fed by the low-temperature fused salt tank through the low-temperature fused salt pump in the electricity utilization trough period and heating the low-temperature fused salt through heat provided by the gas-fired boiler. The fused salt steam-water heat exchanger is used for receiving high-temperature fused salt fed by the high-temperature fused salt tank through the high-temperature fused salt pump during the peak period of electricity consumption and transferring heat energy of the high-temperature fused salt to high-pressure feed water from the water supply system to generate superheated steam; and one part of the superheated steam is fed into a main steam main pipe connected with the gas-fired boiler. The power generation efficiency of the steam turbine can be effectively improved, and efficient utilization of heat energy and flexible adjustment of power grid loads are achieved.

To provide a solvent vapor supply device which has an inexpensive configuration and stabilizes the temperature and density of a solvent vapor supplied to a substrate processing device.SOLUTION: A solvent vapor supply device which supplies a solvent vapor to a substrate processing device that heats a substrate having a film of a block copolymer including at least two polymers under the atmosphere of the solvent vapor to phase-separate the block copolymer comprises: a solvent storage part which is kept at a temperature equal to or greater than the saturation temperature of the solvent stored therein; a preliminary cooling part which preliminarily cools the solvent vapor generated in the solvent storage part; and a temperature adjustment part which adjusts the temperature of the preliminarily-cooled solvent vapor to the target temperature when supplied to the substrate processing device. The temperature adjustment part supplies the solvent vapor adjusted to the target temperature to the substrate processing device.SELECTED DRAWING: Figure 4

This invention belongs to the field of heat exchange technology, specifically relating to a steam comprehensive utilization all-contact desuperheater, including a desuperheater body, a water inlet pipe, a drain port, desuperheater inlet and outlet, and a desuperheating atomization unit. The desuperheater body contains a buffer impeller, a baffle plate, and a protective chamber. The desuperheating atomization unit includes a mounting frame, a recessed splash guard, a perforated plate, and a reaction ring. After being buffered by the buffer impeller, the superheated steam directly contacts the uniform water film on the surface of the reaction ring along the opening direction of the protective chamber for heat exchange, resulting in complete vaporization of the desuperheating water. The steam is discharged after water droplets are separated by the baffle plate, and the condensate is collected and discharged from the desuperheater outlet for subsequent treatment. This invention improves heat exchange efficiency through uniform water flow distribution, and the modular design of the desuperheating atomization unit facilitates maintenance.

The invention provides an integrated temperature and pressure reduction device based on pressure control and a working method, and belongs to the technical field of steam utilization. The problems that in the prior art, temperature and pressure reduction operation of steam is difficult to achieve efficiently and accurately, and the steam utilization efficiency and safety are affected are solved. The temperature and pressure reducing valve comprises a main flowing pipe, a temperature and pressure reducing cavity, an inner sealing face, an outer sealing face and a pressure control spring, a temperature and pressure reducing water inlet is formed in the upper portion of the main flowing pipe, the temperature and pressure reducing cavity is installed in the main flowing pipe, the temperature and pressure reducing water inlet is communicated with the temperature and pressure reducing cavity, and the inner sealing face is arranged on the inner wall of the main flowing pipe. An inner sealing face is arranged on the outer wall of the temperature and pressure reduction cavity, an outer sealing face is arranged on the outer wall of the temperature and pressure reduction cavity and makes contact with the inner sealing face in a matched mode, a plurality of runners are arranged at the tail end of the temperature and pressure reduction cavity, the pressure control spring is installed between the outer wall of the tail end of the temperature and pressure reduction cavity and the inner wall of the flowing main pipe, and the initial state of the pressure control spring is a compressed state. The device is mainly used for reducing temperature and pressure.

The embodiment of the invention provides a wide-load multi-stage steam supply system and an operation method thereof. The wide-load multi-stage steam supply system comprises a steam turbine power generation assembly and a heat supply assembly. The steam turbine power generation assembly comprises a main steam pipeline, a high-pressure cylinder, an intermediate-pressure cylinder, a low-pressure cylinder and a power generator. The heat supply assembly comprises a reheat steam pipeline, a steam supply mother pipeline, a steam supplementing pipeline, a medium-pressure cylinder steam exhaust pipeline and a heat supply network heater. The steam supply mother pipeline is connected with a reheat steam pipeline and an industrial steam supply device; a steam exhaust pipeline of the medium-pressure cylinder is respectively connected with a medium-low pressure communicating pipe and a heating network heater, and the heating network heater is connected with a resident heating device; the steam supplementing pipeline is respectively connected with the steam supply mother pipeline and the heat supply network heater; the steam supplementing pipeline conveys industrial supplied steam of the steam supplying main pipeline to the heat supply network heater for steam supplementing when the unit operates at low load. And meanwhile, the power grid peak regulation requirement and the heat consumer requirement are met, the resident heating and industrial steam supply requirements are considered while the unit peak regulation capacity is not affected in the heating season, and the thermal power unit peak regulation capacity can be released to the maximum extent.

The water vapor cooling device, the compression equipment and the cooling method are used for a water vapor compressor, a water vapor exhaust pipeline is arranged at an outlet of the water vapor compressor, the water vapor cooling device comprises a cooling medium supply assembly and a cooling assembly, and the cooling medium supply assembly is used for providing a cooling medium; the cooling assembly is connected with the water vapor exhaust pipeline and comprises a liquid storage cavity, multiple spray pipes and an adjusting mechanism, the cooling medium supply assembly communicates with the liquid storage cavity, the multiple spray pipes are arranged at intervals, each spray pipe communicates with the liquid storage cavity, and each spray pipe is provided with a nozzle; the adjusting mechanism is arranged in the liquid storage cavity, and the adjusting mechanism is configured to be switched among different working positions according to the flow of the cooling medium so as to selectively communicate the liquid storage cavity with one or more of the spray pipes. The water vapor cooling device is simple in structure, the spraying amount can be adjusted only by changing the flow of cooling water, cooperation of other variables is not needed, and the response speed can be increased.

The present invention relates to a desuperheating water system for superheaters and reheaters of a new type of million-ton tower boiler. At present, in order to ensure the wall temperature safety of the reheater system, the desuperheating water of the reheater is often put into use, and the input of the desuperheating water of the reheater will reduce the efficiency of the boiler, thus ultimately affecting the coal consumption of the unit and increasing the operation cost of the power plant. A desuperheating water system for superheaters and reheaters of a new type of million-ton tower boiler includes: a feed water pump (1), the feed water pump is connected to a group of high-temperature heaters (2), the group of high-temperature heaters are connected in series on the pipeline of the feed water pump, the group of high-temperature heaters are connected to the boiler feed water system, a superheater desuperheating water main pipe (3) is connected between the boiler feed water system and the group of high-temperature heaters, and the superheater desuperheating water main pipe is connected to a primary desuperheating water branch (11) and a secondary desuperheating water branch (12). The present invention is applied to the field of boilers.

A control method for a system in a "steam maintenance mode" after the MFT of a secondary reheat unit boiler comprises the following steps: (1) clarifying the control target of the "steam maintenance mode"; (2) setting the judgment conditions for automatic triggering and automatic exit of the steam maintenance mode; (3) clearly explaining the automatic control of the high, medium and low pressure three-stage bypass and its desuperheating water in the "steam maintenance mode"; (4) detailing the control logic of the feed water pump and the induced draft fan in the "steam maintenance mode"; (5) further explaining the pressure control of the auxiliary steam header and the action of the steam trap group in the steam maintenance mode; (6) giving priority to the supply of the shaft seal in the "steam maintenance mode", while taking into account the control of the condensate system and the auxiliary steam system. The entire control process is transformed from extensive manual control to precise automatic adjustment. It is of great significance to achieve energy saving and consumption reduction of thermal power units, rapid recovery from accident shutdowns, and improvement of the automation level of units.

The utility model provides a waste heat boiler with deoxidization, dust removal and denitration functions. The waste heat boiler comprises a dust removal device, a denitration device, a boiler body, a deaerator, a connecting structure, a heat pipe heat exchanger and a water-water heat exchanger. The dust removal device is arranged at the smoke inlet end of the boiler body, and the heat pipe exchanger is detachably connected with the smoke outlet end of the boiler body through a connecting structure. A water side inlet of the heat pipe exchanger is provided with a water feeding pump, a water side outlet of the heat pipe exchanger is provided with a three-way valve, one end of the three-way valve is connected with an inlet of the water-water heat exchanger, and the other end of the three-way valve is connected with an economizer of the boiler body. According to the waste heat boiler with the oxygen removal, dust removal and denitration functions, the problems that in the related technology, a waste heat boiler only comprises a boiler body heating surface and is difficult to adapt to various industrial waste gas working conditions, so that the boiler heating surface is prone to being severely clogged, and the tail heating surface is prone to being severely corroded at low temperature are solved.

The utility model relates to the technical field of petroleum processing, in particular to a heat source utilization device for an aromatic hydrocarbon extraction process, which comprises a medium-pressure superheated steam generating device, a steam exhaust port of the diesel oil hydrogenation steam turbine is communicated with an inlet end of the desuperheater; and the outlet end of the desuperheater and the outlet end of the temperature and pressure reducer are connected in parallel and then are respectively communicated with the steam inlet of the stripping tower reboiler, the steam inlet of the recovery tower reboiler, the steam inlet of the regeneration tower reboiler, the steam inlet of the benzene tower feeding heater and the steam inlet of the toluene tower reboiler. According to the utility model, surplus low-pressure superheated steam discharged by the diesel hydrogenation steam turbine is used as a heat carrier of the stripping tower reboiler, the recovery tower reboiler, the regeneration tower reboiler, the benzene tower feeding heater and the toluene tower reboiler, so that the use amount of medium-pressure superheated steam is reduced, and the recycling of the surplus low-pressure superheated steam is realized.

The application discloses a full-hydrophobic baffle temperature-regulating subcritical low-calorific-value coal gas-fired boiler, the lower part of the water-cooled wall is a low-calorific-value coal gas combustion zone, the upper part is a variable cross-section heating surface arrangement zone, low-temperature superheaters and low-temperature reheaters are arranged in the front and rear flues of the wall respectively, and flue gas baffles are arranged at the outlets of the two to regulate the temperature. The lower part of the wall is sequentially connected with a high-temperature economizer, a denitration device and a low-temperature economizer for hierarchical arrangement. The heating surfaces such as the low-temperature superheater and the screen-type superheater are horizontally arranged. The application utilizes the baffle temperature regulation to improve the heat transfer efficiency and fuel utilization rate; the hierarchical economizers guarantee the full-load denitration of the boiler and meet the requirement of the flue gas temperature; and the horizontally arranged heating surfaces realize full hydrophobicity, effectively preventing the accumulation of oxide scales.