CN201421269Y

CN201421269Y - Steel slag waste-heat recovering system

Info

Publication number: CN201421269Y
Application number: CN2009201175421U
Authority: CN
Inventors: 周勇; 赵剑云; 陈伟
Original assignee: Hangzhou Boiler Group Co Ltd
Current assignee: Hangzhou Boiler Group Co Ltd
Priority date: 2009-04-13
Filing date: 2009-04-13
Publication date: 2010-03-10
Anticipated expiration: 2019-04-13

Abstract

The utility model discloses a steel slag waste-heat recovering system, which sequentially comprises a steel slag flow distribution device, a water cooled granulation wheel, a primary fluidized bed, aweighing machine, a vibration sieve, a hot slag gain storage hopper, a secondary fluidized bed, a dust-removing device, a blower and a waste heat boiler. The utility model has the advantages that hot-temperature waste heat in the steel slag can be recovered, thereby reducing energy source consumption in the iron steel production; the granulation effect of the steel slag is good, thereby facilitating follow-up free calcium oxide digestion and iron and steel scrap magnetic separation; and the water consumption in cooling steel slag and the environment pollution due to the waste consumption are reduced.

Description

Steel slag waste heat recovery system

Technical field

The utility model relates to a kind of heat recovery technology, relates in particular to that Ferrous Metallurgy is energy-conservation, secondary energy sources reclaim.

Background technology

Iron and steel is the structural material and the highest functional material of output of human consumption maximum.Steel industry is one of pillar industry of Chinese national economy.Along with the rapid growth of iron and steel output, resource, the energy and environmental pollution have become the restrictive factor of restriction China steel industry sustainable development.In the Ferrous Metallurgy process, produce a large amount of high temperature slags, wherein contain a large amount of heats, it is recycled for iron and steel enterprise's energy efficient, water consumption and reduces pollutant emission and is significant.

China's crude steel annual production surpasses 500,000,000 tons, and 1 ton of steel of every production produces 80～150kg slag, produces slag per year above 5,000 ten thousand tons.The liquid steel slag temperature that produces in the steelmaking process is more than 1400 ℃, and the heat content of slag per ton is equivalent to the caloric value of 60kg mark coal approximately.To the iron and steel enterprise of 5,000,000 tons/year of output of steels, annual about 500,000 tons of the slag that produces if can reclaim 50% of contained waste heat wherein, can save 30,000 tons in mark coal every year.As seen the benefit that reclaims the slag waste heat is very considerable.But the discharge of slag is discontinuous, and the magnetic separation steel scrap requires the granularity behind the slag crushing little, and has and clear up the requirement that free calcium oxide is beneficial to later use, so the waste heat recovery difficulty of slag is very big.

The research and the pertinent literature of external recovery slag waste heat aspect are less, only have Japan and Muscovite a few studies result to deliver at present.The quench demonstration plant of method granulation converter slag of wind has been built in NKK and Mitsubishi Heavy Industries Ltd's cooperation; the liquid steel slag gas that will flow out from slag ladle with high pressure air stream (air blast) is broken into the water heat exchange that is blown into behind the slag particle in bell-type boiler and cooling air and the boiler water tube, callable 40%～45% slag waste heat.But this recovery method of steel slag residual heat floor space is big, energy consumption is high, realizes that the industrial production application is very difficult.Russia Ural iron and steel research institute had developed once that slag wind is quenched and vibrated bed-fluid bed heat energy retracting device, and its slag crushing mode also is the employing high pressure air stream, so its floor space is big, energy consumption is high, and the practical application difficulty is very big.Domestic have the broken mode granulation slag of minority producer usefulness gas, but the research of slag waste heat recovery aspect expansion does not as yet have relevant maturation and the technology that provides a reference.Worldwide, the contained physics heat and the heat of transformation that has of liquid towards high temperature slag still do not have industrialized recovery method.To the recovery of slag waste heat, the one, the granulation fragmentation of slag, particle size after cracking is more little, and steel slag particle is fast more with the heat transfer rate of cooling air, and heat exchange efficiency is high more, is not easy more to stick on the heat exchanger wall, helps follow-up magnetic separation and comprehensive utilization more; The 2nd, solve the discontinuous contradiction that requires continuously with heat production of steel-smelting slag-discharging.

Summary of the invention

The utility model provides a kind of steel slag waste heat recovery system, to reach the purpose of effective recovery high-temperature liquid state slag physics heat.

The utility model has solved two key issues that reclaim high-temperature liquid state slag physics heat: the one, to the granulation fragmentation of slag; The 2nd, solve the discontinuous contradiction that requires continuously with heat production of steel-smelting slag-discharging.

The purpose of this utility model is achieved in that

A kind of steel slag waste heat recovery system, it is characterized in that, form in order by steel slag flow distributor, water-cooling granulating wheel, a fluid bed, cooling blower, weighing machine, vibratory sieve, warm sludge grain warehouse, secondary cooling blower, secondary fluid bed, air exhauster, chimney, dust arrester, waste heat boiler, cyclone dust collectors; Steel slag flow distributor is made by refractory material, and has slag flow port, realizes the uniform purpose of slag flow; For guaranteeing at high temperature reliable operation and longer life being arranged, the granulation wheel shaft that is used for slag crushing is cooled off to water flowing; Adopt two-step fluidized bed to carry out gas--the slag heat exchange is provided with weighing machine, vibratory sieve and warm sludge material warehouse, to realize the purpose of continuous heat production between fluid bed and secondary fluid bed; By the high temperature air dedusting that cyclone dust collectors will come out from two-step fluidized bed, send into waste heat boiler then and carry out heat exchange.

Employing the utlity model has following advantage:

(1) with pressure-air granulation slag compares, wheel method granulation slag power consumption significantly reduces (the wind about 17kwh/t slag of granulation power consumption of quenching, the about 2.5kwh/t slag of wheel method granulation), the granulation better effects if of slag, help the gas-slag heat exchange of fluid bed, also more favourable for scrap iron and steel in the magnetic separation slag and follow-up comprehensive utilization;

(2) adopt two-step fluidized bed heat exchange and heat material warehouse is set, can solve steel-making and intermittently slag tap and the contradiction of heat production continuously;

(3) about 60% of the contained waste heat of recyclable high-temperature liquid state slag, add dried slag saving oven dry energy consumption, slag amount of energy saving per ton can reach about 56kg mark coal.

Description of drawings

Fig. 1 is that system of the present utility model constitutes schematic diagram.

Shown in the figure: 1, steel slag flow distributor; 2, water-cooling granulating wheel; 3, fluid bed; 4, cooling blower; 5, weighing machine; 6, vibratory sieve; 7, warm sludge grain warehouse; 8, secondary cooling blower; 9, secondary fluid bed; 10, air exhauster; 11, chimney; 12, dust arrester; 13, waste heat boiler; 14, cyclone dust collectors.

The specific embodiment

As shown in Figure 1, steel slag waste heat recovery system is made up of 2, fluid beds of steel slag flow distributor 1, water-cooling granulating wheel 3, cooling blower 4, weighing machine 5, vibratory sieve 6, warm sludge grain warehouse 7, secondary cooling blower 8, secondary fluid bed 9, air exhauster 10, chimney 11, dust arrester 12, waste heat boiler 13, cyclone dust collectors 14.The uniform purpose of slag flow for realizing entering residual neat recovering system at first pours into steel slag flow distributor 1 with the high-temperature liquid state slag, and steel slag flow distributor is made by refractory material, and has slag flow port; For guaranteeing at high temperature reliable operation and longer life being arranged, the granulation wheel 2 axial water flowings that are used for slag crushing are cooled off; For realizing the purpose of continuous heat production, adopt two-step fluidized bed to carry out gas-slag heat exchange, between fluid bed 3 and secondary fluid bed 9, weighing machine 5, vibratory sieve 6 and warm sludge material warehouse 7 are set; By the high temperature air dedusting that cyclone dust collectors 14 will come out from two-step fluidized bed, send into waste heat boiler 13 then and carry out heat exchange.

The process of slag waste heat recovery is: the temperature that steelmaking process went out is that the high-temperature liquid state slag more than 1400 ℃ is contained in to be transported in the slag ladle and handles on-the-spotly, pours into steel slag flow distributor 1; The liquid steel slag that flows out from steel slag flow distributor falls from eminence, and water-cooling granulating wheel 2 collisions that are rotated smash dishes out, and falls into one-level fluid bed 3, with the air heat exchange that is blown into from the bottom, is cooled to about 800 ℃ and discharges from a fluid bed; The warm sludge grain of discharging from fluid bed 3 is stored in the warm sludge grain warehouse 7 behind weighing machine 5, vibratory sieve 6 (removing big footpath particle); The warm sludge grain that is stored in the warm sludge grain warehouse enters secondary fluid bed 9 and air heat exchange continuously, is cooled to about 350 ℃ and discharges, and transports the stewing workshop of magnetic separation workshop or heat to and makes subsequent treatment; The high temperature air that fluid bed and secondary fluid bed are heated by slag particle enters waste heat boiler 13 heat exchange after cyclone dust collectors 14 dedustings, be transformed into steam or electric power is used; The air of finishing heat exchange in waste heat boiler is sent to chimney 11 emptyings by exhaust blower after dust arrester is collected tiny grit.

Claims

1. steel slag waste heat recovery system; include electric control system; it is characterized in that, combine integral body in order by steel slag flow distributor (1), water-cooling granulating wheel (2), a fluid bed (3), a cooling blower (4), warm sludge grain warehouse (7), secondary cooling blower (8), secondary fluid bed (9), air exhauster (10), chimney (11), dust arrester (12), waste heat boiler (13), cyclone dust collectors (14).

2. a kind of steel slag waste heat recovery system according to claim 1 is characterized in that, also is provided with weighing machine (5) and vibratory sieve (6) between a cooling blower (4) and warm sludge grain warehouse (7) in order.