CN2199205Y

CN2199205Y - Indirect heating calciner for active lime

Info

Publication number: CN2199205Y
Application number: CN 94215597
Authority: CN
Inventors: 董致和
Original assignee: Wuhan Iron And Steel Design And Research Institute Ministry Of Metallurgical Industry
Current assignee: Wuhan Iron And Steel Design And Research Institute Ministry Of Metallurgical Industry
Priority date: 1994-07-06
Filing date: 1994-07-06
Publication date: 1995-05-31
Anticipated expiration: 2004-07-06

Abstract

The utility model relates to a calciner for active lime, particularly an indirect heating calciner for active lime, which comprises a baiting hopper (1), a calcining chamber (2), a discharge valve (3), a blast chamber (4), a flame path (5), an air flue (6) and a steel-construction supporting frame (7). The flue gas heats a separation wall which is shared by a heating zone of the calcining chamber and the flame path, and with the conduction and radiant heat transfer, limestone is heated in the heating zone and finished calcination. The calcined limestone does not directly contact the flue gas and can not be contaminated by ashes and harmful elements of the flue gas, and thus the quality of the active lime can reach the standard of first quality ware or speciality product prescribed by ZBQ27001-85; the indirect heating calciner has small land occupation and few investment, and is especially suitable for the local short-stage iron and steel plants.

Description

Indirect heating calciner for active lime

The utility model relates to a kind of calciner of quickened lime, particularly indirect heating quickened lime calcining furnace.

Quickened lime is slag making, the sweetening agent that is used for hot metal pretreatment, the outer smart stove of molten steel stove, top-blown oxygen converter, top and bottom combined blown converter and steelmaking arc furnace.It is for the strengthening smelting process, and the quality that reduces furnace charge consumption and raising steel is all significant.

At present, the calcining kiln of China's production metallurgy lime all is reverse-flow single thorax shaft furnace.How to make fuel with coke or anthracite block coal.This kiln incinerating metallurgy lime also has the certain activity degree, but its activity degree is lower, is generally 80～120 degree, and best also can only be near 200 degree.Therefore, after single thorax shaft furnace that each Metallurgical Factory of China has is only transformed, just might produce the high-quality quickened lime that meets the industry standard ZBQ27001-85 of the People's Republic of China (PRC).Technical difficulty and investment to the technological transformation of existing single thorax shaft furnace are all bigger.

Recent years, China has introduced several quickened lime production units from external: mainly be widely different rotary kiln, the two now thoraxes of mayer also flow the heat accumulating type shaft furnace and modified version mayer shaft furnace now.But every construction investment of widely different rotary kiln of introduction is bigger, about 5,000 ten thousand Renminbi.And this kiln is also relatively harsher to demanded fuel.The coal gas calorific value requires to reach 3.3910 ³KJ/m ³, the dustiness 10mg/m of coal gas ³, coal gas must pass through desulfurization, and sulphur content requires S＜0.02～0.25%.Its burnup is generally the 5000KJ./kg quickened lime.Be difficult to bear for the so harsh general iron and steel enterprise of fuel condition condition.From the two now thoraxes of the mayer of external introduction and flow the heat accumulating type shaft furnace, produce 70～600 tons daily.Require to adopt oil, Sweet natural gas, or mixed gas is done fuel.To the calorific value of fuel, dustiness and sulphur content have strict requirement equally.The modified version mayer that somewhere iron and steel enterprise introduces from Japan is shaft furnace now, adopts coke or coal dust to do fuel.Require the sulphur content 0.4～0.5% of coal, ash content＜10%, the softening temperature of ash content simultaneously〉1250 ℃.In order to reduce ash content and sulphur quality influence to the quickened lime forged, powder of general＜3mm screens out behind the kiln discharge, the ash sub-sieve has fallen, heat content, be after bituminous coal is dropped into combustion chamber (4) burning, quirk (5) horizontal flow that its products of combustion high-temperature flue gas enters in the body of heater rises again, enters flue (6) through three folding journeys, enters atmosphere by chimney.Build shared partition wall with quirk (5) with refractory brick because the wall of calcining compartment is a calcining compartment (2), it separated flue gas flow with by the materials flow of incinerating lime.Flue gas heats party wall through conduction and radiative transfer in flow process, makes Wingdale preheating in the calcining compartment preheating section, heats and finish high-temperature calcination in heating zone to become quickened lime.Fall in the cooling section then and cool off, and wait for and extracting by bleeder valve (3) by working specification.The characteristics of the party wall between the heating zone of calcining compartment (2) and the quirk (5) are to adopt the siliceous quarle of carbonization of high thermal conductivity to build by laying bricks or stones to form.The partition wall that the siliceous quarle of this carbonization is built by laying bricks or stones had both helped conducting heat, and the body of heater that helps whole quickened lime calcining furnace again is stable.The all wts of body of heater is supported by steel structure support (7).

Accompanying drawing 1 is the structural representation of indirect heating quickened lime calcining furnace, and 1 is hopper among the figure, and 2 is calcining compartment, and 3 is bleeder valve, and 4 is the combustion chamber, and 5 is quirk, and 6 is flue, and 7 is steel structure support.

Because the utility model adopted the indirect heating mode, finish the pollution that quickened lime after the calcining is not subjected to harmful element in ash content and the flue gas, particularly not carburetting, thus guaranteed the quality of quickened lime.Indirect heating quickened lime calcining furnace can use various fuel, adds the calorific value of fuel of heat request except that satisfying, and does not have other harsh requirements.The utility model utilizes coal to do fuel, and requiring to use industrial steam coal is bituminous coal, and its calorific value can not be lower than 23000KJ/Kg coal～25000KJ/kg.Suitable with the energy consumption index of widely different rotary kiln active lime calcination.Produce the less investment of the indirect heating quickened lime calcining furnace of 3000～5000 tons of quickened limes per year, be about 30～400,000 yuans, (not comprising chimney), floor space is little, last detective, be specially adapted to the S LOCAL IRON AND STEEL WORKS of short flow process, as long as go into the quality of hearthstone lime stone when meeting the one-level of YB2403-79 standard code and select quality, the quality of producing quickened lime can reach ZBQ27001-85 standard code first grade or select quality fully.Powder that sulphur is high also partly screens out.Increased the loss of finished product so inevitably, even so, its activity degree also is less than the standard of first grade.

Chinese patent 89218318.7 provides a kind of double-deck fuel external combustion type lime kiln, and external combustion type is adopted in the thermal source design, and has designed the structure of double-deck fuel, but still is direct heating, can't avoid direct-fired defective.

More than several combustion equipment all be adopt direct-fired method, promptly the flue gas that is produced after the fuel combustion be heated the incinerating Wingdale and directly contact and heat.Harmful in the flue gas that the shortcoming of this heating means is subjected to being produced after the ash content of fuel and the fuel combustion by the incinerating Wingdale do not have plain pollution.For guaranteeing the quality of quickened lime, strict requirement must be arranged to fuel.Construction investment is also bigger.

The purpose of this utility model is the shortcoming and defect that the production unit of quickened lime is produced in calcining at direct heating, a kind of indirect heating quickened lime calcining furnace is proposed, to reduce by the pollution of calcined limestone, particularly not carburetting, guarantee the quality of quickened lime, and facility investment is few, and floor space is little, is specially adapted to the S LOCAL IRON AND STEEL WORKS of short flow process.

Indirect heating quickened lime calcining furnace described in the utility model is based on the heat exchange principle of used for industrial furnace heat-exchanger rig and a kind of stove with indirect heating method active lime calcination of designing.So-called indirect heating promptly is heated the incinerating Wingdale and does not directly contact with fuel and products of combustion-flue gas thereof, but through the conduction and the radiative transfer of furnace wall, Wingdale is heated and calcines.The furnace binding of indirect heating quickened lime calcining furnace is fairly simple, and it comprises hopper (1), calcining compartment (2), bleeder valve (3), combustion chamber (4), quirk (5), flue (6) and steel structure support (7).By the incinerating Wingdale, landing naturally through hopper (1) enters calcining compartment (2), and calcining compartment divides three working zones, i.e. preheating section, heating zone and cooling section from top to bottom.Wingdale is finished calcination process in heating zone after the preheating section preheating.Temperature in the heating zone is strict controlled in 950～1050 ℃ of scopes, the highest must not be above 1100 ℃.In order to avoid the quickened lime burning reduces its activity degree.The quickened lime that is sintered into is extracted through bleeder valve 3, and in the sealing bucket of packing into.Calcined limestone is required

Embodiment:

Accompanying drawing 1 provides an embodiment of indirect heating quickened lime calcining furnace, and it comprises hopper (1), calcining compartment (2), bleeder valve (3), combustion chamber (4), quirk (5), flue (6) and steel structure support (7).Calcining compartment is divided into three working zones, i.e. preheating section, heating zone and cooling section from top to bottom.By the incinerating Wingdale, landing naturally through hopper (1) enters calcining compartment (2).Bituminous coal drops into combustion chamber (4) burning, and quirk (5) horizontal flow that the products of combustion high-temperature flue gas enters in the body of heater rises again, enters flue (6) through three folding journeys and enters atmosphere by chimney.The wall of the wall of calcining compartment (2) and quirk (5) is the shared partition wall of building by laying bricks or stones with refractory brick, it separated flue gas flow with by the lime kilning materials flow.In heating zone, this partition wall is built by laying bricks or stones by the siliceous quarle of the carbonization of high thermal conductivity and is formed.

Claims

1, a kind of indirect heating quickened lime calcining furnace is characterized in that it comprises hopper (1), calcining compartment (2), bleeder valve (3), combustion chamber (4), quirk (5), flue (6) and steel structure support (7).

2, calcining furnace according to claim 1 is characterized in that described calcining compartment (2) is divided into three working zones, i.e. preheating section, heating zone and cooling section from top to bottom.

3,, it is characterized in that being shared partition wall between described calcining compartment (2) and the quirk (5) that this partition wall is built by laying bricks or stones by the siliceous quarle of the carbonization of high thermal conductivity in heating zone and formed according to wanting profit to require 1 described calcining furnace.