CN102505059A

CN102505059A - Sludge based green reducing agent and use method thereof

Info

Publication number: CN102505059A
Application number: CN2011103709340A
Authority: CN
Inventors: 李宇; 周贵友; 刘晓明; 樊涌; 苍大强
Original assignee: University of Science and Technology Beijing USTB
Current assignee: University of Science and Technology Beijing USTB
Priority date: 2011-11-21
Filing date: 2011-11-21
Publication date: 2012-06-20

Abstract

The present invention relates to a sludge based green reducing agent and a use method thereof, and belongs to the technical field of resource utilization and environmental protection. The sludge based green reducing agent is characterized in that the sludge based green reducing agent is prepared by adopting dried sludge as a main raw material, wherein the heat value of the dried sludge is more than or equal to 2000 Kcal/kg, the water content of the dried sludge is less than 10%, and the ingredient is a silicon-aluminum based material; during the using process, the sludge based reducing agent is applied in the metallurgy process with a temperature more than 1000 DEG C, wherein the process comprises blast furnace smelting, smelting reduction, slag smelting reduction and iron recovery, and other high temperature processes. The sludge based green reducing agent and the method of the present invention have the following advantages that: the sludge based green reducing agent contains the adjustable silicon-aluminum based component, such that the alkalinity of the reducing process can be adjusted according to the requirement, or the component can be changed according to the requirement of the later reduction slag utilization; the sludge is adopted as the reducing agent of the high temperature metallurgy process ( the temperature is more than 1000 DEG C), such that the coal fines can be completely or partly replaced, the waste is changed into valuables, and the environmental problems of dioxin forming during the sludge thermal state utilization process, and the like can be reduced or avoided.

Description

Green reductive agent of a kind of mud base and method of use

Technical field

The invention belongs to the utilization of resources and environmental protection technical field, especially in the hot process of utilizing of mud.

Background technology

Mud contains a large amount of carbon and organic constituent, is a kind of solid waste with higher calorific value, and its calorific value reaches 2000 ~ 3500Kcal/Kg.Therefore, mud can be used as reductive agent and reduce extracting metals.Patent CN201010282005.X; CN201010282001.1 has reported the method for making reductive agent reducing roasting rhombohedral iron ore, pyrolusite with mud; But the Heating temperature of this method is between 500 ~ 800 ℃, and this temperature range is a large amount of TRs that form of obnoxious flavour such as Dioxins just.Thus it is clear that, adopt this method can not solve the environmental problem that mud utilizes.

If mud can utilize at the high-temperature area more than 1000 ℃, so, the Dioxins that will avoid 300 ~ 800 ℃ fast generates the humidity province, significantly reduces or avoids Dioxins to form; Decompose toxic substances such as germ simultaneously, realize the environmental protection utilization of mud.

Blast furnace ironmaking in the metallurgical process, fused reduction iron-smelting, iron content slag reduction recovery iron etc. are such high temperature reduction process, and temperature of reaction is higher than 1400 ℃.Behind sludge drying; With other raw material crushing, mix; Spray into fast then in blast furnace, fusion reducing furnace or the smelting reduction stove, then can make the mud temperature be increased to the high temperature more than 1300 ℃ fast, significantly reduce obnoxious flavoures such as perhaps having avoided Dioxins and generate; And in reaction tank, react reductive agent as high temperature reduction, make full use of it and contained the characteristics of fixed carbon and reduction components.

On the other hand; Owing to contain a large amount of inorganic components and heavy metal ion in the mud; Contain a large amount of inorganic components in the batching that is added, can select batching as required, inorganic component is fused in the slag in the reduction reaction process; Thereby can utilize these components to adjust the basicity of metallurgical reduction process, guarantee that reductive efficiently carries out; Perhaps, change the composition of optimizing slag according to the needs of reduction back slag later use.

Summary of the invention

One of the object of the invention: substitute coal dust, realize energy-conservation.Because the mud after the mummification has the calorific value near brown coal, therefore can in commercial run, substitute coal dust.Because metallurgical industry is the industry that the energy and material are imported and exported on a big scale, even contain objectionable constituent such as heavy metal, Cl and P ion in the mud, the ratio of the alternative coal dust of control dewatered sludge, can so that these objectionable constituent the influence of main technology and product is ignored.

Two of the object of the invention: the Dioxins that solves the hot utilization of mud forms problem.There are about 300 ~ 400 ℃ and 800 ℃ two best formation temperature districts in Dioxins.If can avoid this TR fast, so then can significantly reduce the formation of Dioxins; Hot environment more than 1400 ℃ also can be decomposed Dioxins fully simultaneously.Therefore if mud is carried out hot utilization, selecting the high-temperature reaction process more than 1400 ℃ so, is the key that guarantees whole technology environmental protection; Simultaneously so high temperature range can realize fully that also the nothing of mud poisons.

Three of the object of the invention: the step recycling of realizing mud.Processes such as the blast furnace ironmaking in the metallurgical process, fused reduction iron-smelting, iron content slag reduction recovery iron all are the high temperature reduction processes, form vitreous state after the high-temperature slag shrend that the reaction back forms, at present fields such as widespread use and cement, concrete.Mud is added high-temperature smelting process as reductive agent, and the compositions such as carbon that have calorific value in the mud substitute coal dust as reductive agent or heat-generating agent, and remaining inorganic component then mixes slag, finally after shrend, form the vitreous state Water Quenching Slag, and obtain further to utilize.Because this slag is vitreous state, not only have good active, and can also consolidating heavy metal etc. harmful ion, guaranteed the complete resource utilization and the environment-friendly and green utilization of mud.

Green reductive agent of a kind of mud base and method of use is characterized in that main raw material is a dewatered sludge, account for 70 ~ 100%, derive from municipal wastewater mud, paper mill sludge or channel cleanout mud, and calorific value is that water ratio is less than 10% more than or equal to 2000Kcal/kg; Auxiliary material is one or more in silica sand, Feldspar Powder, mine tailing, flyash, coal gangue, coal slime, resinous shale, clay mineral, rhombspar, Wingdale, unslaked lime, white lime, cement, red mud, the metallurgical dust mud etc., accounts for 0 ~ 30%.

The characteristic of green reductive agent of described mud base and method of use also is to reclaim the reductive agent that iron, melting, reducing and smelting etc. are higher than 1000 ℃ of pyroprocesses as blast furnace ironmaking, slag smelting reduction in the metallurgy, can substitute coal dust wholly or in part.

The invention provides the prescription and the embodiment of the green reductive agent of several kinds of mud bases.It is simple that this reductive agent has an operating procedure, is connected effective with existing technology, need be equipped with other auxiliary facilitys, and cost of investment is low, and is easy to implement to promote.

Embodiment

Embodiment one: the dewatered sludge of certain sewage work as the green reductive agent main raw material of mud base, is accounted for 100%; The mud ash content accounts for 35%, fixed carbon 8%, thermal value 15MJ/Kg, water ratio 5%.

The green reductive agent of mud base is sprayed in 1500 ℃ of fusion reduction reaction devices, and when basicity was 1.1, the recovery of iron can reach 85%.

Embodiment two: the dewatered sludge of certain sewage work as the green reductive agent main raw material of mud base, is accounted for 80%, fixed carbon 8%, thermal value 15MJ/Kg, water ratio 5%; Auxiliary material is a flyash, accounts for 20%.

The green reductive agent of mud base is added 1600 ℃ high-temperature fusion attitude bessemer furnace slag and mixes; When the green reductive agent add-on of mud base be the slag quality 60% the time, the recovery of iron also reaches 90.97%, reduction ratio reaches 94.30% .

Claims

1. the green reductive agent of mud base is characterized in that main raw material is a dewatered sludge, accounts for 70 ~ 100%, derives from municipal wastewater mud, paper mill sludge or channel cleanout mud, and calorific value is that water ratio is less than 10% more than or equal to 2000Kcal/kg; Auxiliary material is one or more in silica sand, Feldspar Powder, mine tailing, flyash, coal gangue, coal slime, resinous shale, clay mineral, rhombspar, Wingdale, unslaked lime, white lime, cement, red mud, the metallurgical dust mud etc., accounts for 0 ~ 30%.

2. the green reductive agent of mud base as claimed in claim 1 is characterized in that reclaiming the reductive agent that iron, melting, reducing and smelting etc. are higher than 1000 ℃ of pyroprocesses as blast furnace ironmaking, slag smelting reduction in the metallurgy, can substitute coal dust wholly or in part.