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CN-122015509-A - Submerged arc furnace in-situ mold casting and iron slag separation waste heat recovery power generation system

CN122015509ACN 122015509 ACN122015509 ACN 122015509ACN-122015509-A

Abstract

The invention relates to the technical field of waste heat recovery and utilization of submerged arc furnaces and discloses a submerged arc furnace front mold casting and iron slag separation waste heat recovery power generation system which comprises a pretreatment and system initialization module, a split-flow separation and primary heat exchange module, an iron slag deep cooling and sensible heat recovery module, a flue gas summarizing heat exchange and power generation module and a tail end closed loop and waste heat secondary utilization module; the pretreatment and system initialization module comprises a water dissolving system, a DCS control system, a temperature sensor, a pressure sensor, a flue gas flowmeter, an external circulating fan, a cold air regulating valve and a radiant heat exchange pipeline, wherein the system can effectively recycle waste heat and radiant heat generated in the cooling process of molten iron and iron slag of a chromite hot furnace, realize the efficient recycling of heat energy, reduce the environmental temperature of a production workshop and provide a safe, environment-friendly and air-freshening working environment for production workers.

Inventors

  • ZHANG XIAOGUANG
  • WANG XILAI
  • MU XIANG
  • Mu Fujie
  • Wang aotian

Assignees

  • 天纵泓光热科(宁夏)研发股份有限公司

Dates

Publication Date
20260512
Application Date
20251222

Claims (6)

  1. 1. The submerged arc furnace in-situ mold casting and iron slag separation waste heat recovery power generation system is characterized by comprising the following modules and components: the system comprises a pretreatment and system initialization module, a split-flow separation and primary heat exchange module, an iron slag deep cooling and sensible heat recovery module, a flue gas summarizing heat exchange and power generation module and a tail end closed loop and waste heat secondary utilization module; the pretreatment and system initialization module comprises a water dissolving system, a DCS control system, a temperature sensor, a pressure sensor, a flue gas flowmeter, an external circulating fan, a cold air regulating valve and a radiant heat exchange pipeline; The split-flow separation and primary heat exchange module comprises a slag grate, a small waste heat recovery channel smoke hood, a ground mold radiant heat recovery smoke hood, a radiant heat exchange pipeline, an external circulating fan and a cold air regulating valve; the iron slag deep cooling and sensible heat recovery module comprises a grate cooler, a crusher and a high-temperature flue gas air outlet; the flue gas collecting heat exchange and power generation module comprises a flue gas collecting pipeline, a wind control valve, a waste heat boiler, a bag-type dust remover, an exhaust fan and a condensing steam turbine generator unit; The tail end closed loop and waste heat secondary utilization module comprises a condenser, a thermal deaerator, an ash discharging system and a workshop heating branch pipeline.
  2. 2. The submerged arc furnace on-site casting and iron slag separation waste heat recovery power generation system is characterized in that the water melting system comprises a softening device, a desalting device and a thermal deaerator, softening, desalting and thermal deaeration are sequentially carried out, water supply conductivity is less than or equal to 0.1 mu S/cm, oxygen content after deaeration is less than or equal to 0.05mg/L, pressure of the thermal deaerator is maintained to be 0.02-0.05MPa, a DCS control system is connected with operation data of each device, waste heat boiler pressure is preset to be 3.5MPa, rotating speed of a turbine generator is 3000 revolutions per minute, a temperature sensor, a pressure sensor and a flue gas flowmeter are used for collecting flue gas temperature, boiler pressure and flue gas flow data respectively, an external circulating fan is used for introducing normal-temperature air and matched with a radiant heat exchange pipeline for preheating, initial opening of a cold air regulating valve is 30% and used for controlling fan supply flow, and the radiant heat exchange pipeline is used for receiving high-temperature flue gas and realizing heat transfer.
  3. 3. The submerged arc furnace front-mold pouring and iron slag separation waste heat recovery power generation system is characterized in that a slag grate is provided with a grate plate with the aperture of 8-10cm and used for shunting molten iron and iron slag, a high-temperature resistant heat preservation layer and castable are arranged in a small waste heat recovery channel fume hood, the thickness of the outer heat preservation layer is 6cm and is connected with a submerged arc furnace tapping hole and the slag grate, the submerged arc furnace radiation heat recovery fume hood seals an area above the submerged arc furnace, a plurality of parallel radiation heat exchange pipelines are arranged in the submerged arc furnace radiation heat recovery fume hood and are connected with each other through heat-resistant steel sheets, 10-15cm heat preservation layers are arranged between the pipelines and the fume hood, the radiation heat exchange pipelines are arranged in a straight-through type mode, the top of the radiation heat exchange pipeline is connected with a gas distribution box, the gas distribution box is gradually enlarged from far to near, the external circulation fan is matched with a cold air regulating valve according to the formula of alpha=30% +kX (T-800 ℃), alpha is the opening of a cold air valve, the upper limit is 80%, k is the real-time temperature of fume, and the k is the regulating coefficient and the value is 0.05%.C.
  4. 4. The submerged arc furnace in-situ casting and iron slag separation waste heat recovery power generation system is characterized in that the grate cooler comprises a high-pressure cooling fan, an alloy grate bed and a hydraulic system, the air supply speed of the high-pressure cooling fan is 8-12m/s, the alloy grate bed is resistant to 1300 ℃ and comprises a fixed grate plate and a movable grate plate, the hydraulic system drives the movable grate plate to do 10-15 times/min of reciprocating motion, the crusher is used for crushing massive iron slag into granular materials with the diameter of <3cm, and the high-temperature flue gas air outlet is used for collecting high-temperature flue gas generated in the iron slag cooling process.
  5. 5. The submerged arc furnace front-mold pouring and iron slag separation waste heat recovery power generation system is characterized in that a flue gas collecting pipeline is connected with a flue gas outlet of a ground-mold radiation heat recovery smoke hood, a slag grate and a grate cooler, the opening of a wind control valve is 80% when a single furnace is in tapping, air quantity is distributed according to the proportion of 30-35% of each furnace when a plurality of furnaces are cooperated, the waste heat boiler adopts a film type wall structure, a multi-layer heat exchange pipeline is arranged inside the waste heat boiler, the pressure grade is 3.2-3.82MPa, the outer side of the waste heat boiler is a composite heat insulation structure with an outer-layer color steel plate and an inner-layer fireproof heat insulation material, a multi-layer filter bag is arranged inside the bag-type dust collector, an ash discharging system is arranged at the bottom of the bag-type dust collector, the exhaust fan is of a centrifugal structure and is connected with a chimney, the pressure grade of a condensing steam turbine generator is 2.5MPa, the rotating speed is 3000 rpm, the exhaust pressure is 0.08-0.1MPa, and an output shaft is connected with a power generator.
  6. 6. The submerged arc furnace in-situ casting and iron slag separation waste heat recovery power generation system according to claim 1 is characterized in that the condenser is used for condensing exhaust steam discharged by the steam turbine into water, the thermal deaerator is used for receiving the condensed water discharged by the condenser and deoxidizing again, the ash discharge system is used for collecting dust filtered by the bag-type dust collector and discharging the dust, and the workshop heating branch pipe is connected with a flue gas outlet of the grate cooler and is started in winter and used for guiding the dust into workshop heating.

Description

Submerged arc furnace in-situ mold casting and iron slag separation waste heat recovery power generation system Technical Field The invention relates to the technical field of waste heat recovery and utilization of submerged arc furnaces, in particular to a submerged arc furnace front mold casting and iron slag separation waste heat recovery power generation system. Background The chromite hot furnace is an indispensable important device in the special ferrous metallurgy industry, the recycling of other heat resources has important significance for reducing energy consumption and reducing environmental pollution, at present, a chromite hot furnace flue gas waste heat recovery power generation system can meet certain heat recovery requirements, but has the characteristics of low utilization rate of waste heat of iron slag and the like due to casting in front of the furnace, slag iron separation, production of 1 ton of ferrochrome, production of 0.6-0.8 ton of iron slag, and particularly potential safety hazard to working environment and human health of a production site due to high-temperature radiant heat generated in the casting slag iron separation process; The existing waste heat recovery system generally adopts a form that a conventional air taking pipeline, a circulating fan and a return air pipeline of a circular cooler are connected with a dust remover for tapping and pouring flue gas, wherein the flue gas is only recovered during the production of an ore smelting furnace. Although this system enables partial flue gas particulate recovery, there are some disadvantages: firstly, the waste heat of the cast iron slag is not recovered, and the heat carried by the iron slag during casting is wasted; secondly, the heat carried by the slag iron is dissipated in a production workshop in the form of radiant heat, so that the working environment of workers is greatly influenced, and the bodies of the workers in the environment are easy to cause problems for a long time; therefore, development of a novel submerged arc furnace front-cast molten iron and slag iron waste heat recovery system is urgently needed to solve the problems in the prior art, and the system can effectively recycle waste heat and radiant heat generated in the cooling process of the chromite submerged arc furnace molten iron and slag, so that efficient recycling of heat energy is realized, the environmental temperature of a production workshop is reduced, and a safe, environment-friendly and fresh-air working environment is provided for production workers. Disclosure of Invention The invention aims to provide a submerged arc furnace in-situ casting and iron slag separation waste heat recovery power generation system, which can effectively recycle waste heat and radiant heat generated in the cooling process of molten iron and iron slag of a chromite furnace, realize the efficient recycling of heat energy, reduce the environmental temperature of a production workshop and provide a safe, environment-friendly and fresh-air working environment for production workers. In order to achieve the above purpose, the present invention adopts the following technical scheme: an in-situ mold casting and iron slag separation waste heat recovery power generation system for an ore furnace comprises the following modules and components: the system comprises a pretreatment and system initialization module, a split-flow separation and primary heat exchange module, an iron slag deep cooling and sensible heat recovery module, a flue gas summarizing heat exchange and power generation module and a tail end closed loop and waste heat secondary utilization module; the pretreatment and system initialization module comprises a water dissolving system, a DCS control system, a temperature sensor, a pressure sensor, a flue gas flowmeter, an external circulating fan, a cold air regulating valve and a radiant heat exchange pipeline; The split-flow separation and primary heat exchange module comprises a slag grate, a small waste heat recovery channel smoke hood, a ground mold radiant heat recovery smoke hood, a radiant heat exchange pipeline, an external circulating fan and a cold air regulating valve; the iron slag deep cooling and sensible heat recovery module comprises a grate cooler, a crusher and a high-temperature flue gas air outlet; the flue gas collecting heat exchange and power generation module comprises a flue gas collecting pipeline, a wind control valve, a waste heat boiler, a bag-type dust remover, an exhaust fan and a condensing steam turbine generator unit; The tail end closed loop and waste heat secondary utilization module comprises a condenser, a thermal deaerator, an ash discharging system and a workshop heating branch pipeline. The water dissolving system comprises a softening device, a desalting device and a thermal deaerator, wherein softening, desalting and thermal deaerating are sequentially carried out, the water supply conductivity is less than or eq