Forestry meets Steel. A system study of the possibility to produce DRI (directly Reduced Iron) using gasified biomass.

• The main production of primy Iron from ore is now made by reduction using fossil reductants, either by producing hot metal in the blast furnace process or as directly reduced iron with natural gas as most common reductant. The climate gas impact would be improved if at least pt of the reductants could be produced from Biomass. One possibility could be to use gasified Biomass to produce DRI (Directly Reduced Iron). This is studied in a cooperative project where LTU, MEFOS, ETC and five industries in the eas forestry & pulp, mining, iron and gas e involved. The investigation is made in four pts where the first one is on the supply of biomass. A lge amount of Biomass has to be delivered into a single site to exchange a lge amount of fossil reductant. Also, forestry by-products should be used as most of the round wood is reserved for other uses. Hvesting, logistics and economics e considered. The second pt is on the gasification of the biomass, where the aim is to use to produce hot gas that can be used directly. Pilot experiments e cried out using oxygen in an entrained flow gasifier. The third pt is on the metallurgical processes, where reduction tests e cried out with gas that can be produced in the gasifier. The limitations of the gas content e studied as well as the effect on DRI. Also the suitability of the DRI product is evaluated. The fourth pt of the project uses process integration to model the whole process chain. The results from the other project pts e used to build the system model. It is then used for technical economic optimization the whole system hvesting- Transport-gasifier-direct reduction-use of DRI. The first use of the system model has been to find the best supply road (hvesting, pretreatment and transport) for a chosen production case The simulations indicated that the supply of residuals is possible but will need material from a lge pt of the north Sweden wood ea, and that a relatively lge amount of gas recirculation is needed. The continuing work is focused on further development of the optimization tool and the use of it for more extensive studies of the trade-off between pameters of metallurgy, gasification and supply. The result can be important for evaluation of future industrial applications. It could also help in understanding the effect of governmental control instruments. The paper will mainly focus on the process integration study.

Ämnesord

TEKNIK OCH TEKNOLOGIER  -- Maskinteknik -- Energiteknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Mechanical Engineering -- Energy Engineering (hsv//eng)

Nyckelord

Biomass

Energy

Gasification

Iron making. dri

Process integration

System models

Blast furnaces

Economic and social effects

Energy efficiency

Environmental impact

Forestry

Gases

Iron

Metallurgy

Ore reduction

Timber

Blast furnace process

Directly reduced irons

Entrained flow gasifiers

Iron making

Technical-economic optimization

Iron ore reduction

Energiteknik

Attraktivt samhällsbyggande (FOI)

Förnybar energi (FOI)

Hållbara transporter (FOI)

Publikations- och innehållstyp

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