Innovative Biomass utilization Iron & Steelmaking

RED 902 Prof. Dr. Paulo Santos Assis

2013/2

General overview of Iron & Steelmaking

100% scrap

30% scrap+ 70% pig iron

Understanding the Sintering Process

Pelletizing

Blast Furnace

Wall conditions Cooling capacity

Gunning & grouting Temperature monitoring

Burden Distribution

Control of heat losses/ Control of central flow Center coke charging

Low alkali input

High permeability Cohesive zone control

Hearth Permeability

- Coke center charging

- High quality coke

Cooling efficiency

- Hearth chiller

- grouting

Tap-hole Management

- drilling

- High performance clay

- tap hole length

Wear monitoring

- temperature, flux

- modeling

Direct Reduction Process

New process: COREX

Steelmaking Processes

E AF : E l e c t r i c Ar c F u r n a c e

L D / B O F / B O S : L D P r o c e s s

Source: Meenakshi, P. Elements of Environmental Science and Engineering - pg 227; 237 – Ed.

Prentice Hall, Delhi 312p., 2008

1

2

3

4

5

6Natural Gas 21%

Energy

Non-renewable 82%

Oil 33%

Coal 22%

Biomass 11%

Nuclear power 6%

Hydropower, geothermal,

solar, wind, 3%

Renewable 18%

Source of Energy

Solid Biomass Fuels

Wood logs and pellets

Charcoal

Agricultural waste

(Stalks & other plant debris)

Timbering wastes

(Branches, treetops & wood chips)

Animal wastes (Dung)

Aquatic Urban wastes (Aquatic plants Kelp &

water hyacinths)

Urban wastes (Paper, cardboard & other

combustible materials)

Direct burning Conversion to gaseous and

liquid biofuels

Gaseous Biofuels

Synthetic natural gas (Biogas)

Wood gas

Liquid Biofuels

Ethanol

Methanol

Gasohol

Overview of Energy in the World

Why Iron and Steelmaking in the World is feasible ?

1. Iron ore source: overall (for the next 1000 years or more)

2. Electric functions with low price, i.e. in comparison with other alloys like Ni-Co

[Normally the prices of Si-Steel is 1/3 of the equivalent alloy. Other hand, the price of Si-Steel is by USD 1650/ton or even more]

3. Structure can be modified by Alloys adding or even by Temperature (CCC to CFC)

4. Diffusion of Carbon at high Temperatures, till 2 %. It seems to be unique for Metals.

Why Iron and Steelmaking in the World is feasible ?

5. Low cost in comparison with other Materials that can be substituted

6. Low Consumption of Energy in comparison with the Al (Primary)

0

1

2

3

4

5

6

7

8

9

Steel

Concrete

Aluminium

USD/kg/km

Material

Cu – Ti – Carbon Based

0

5

10

15

20

25

30

35

40

45

50

Primary Steel

SecondarySteel

PrimaryAluminium

SecondaryAluminium

GJ/ M Ton

Why Iron and Steelmaking in the World is feasible ?

7. Wastes with low risk (Normally is 2A or even 2B). Possibility for recycling 100 %

[Although high volume of Waste (it could be more than 1 t/t Steel), all of them could be

recycled in Steel or even Other Industry (Cement Producer)]

By CST [Arcelor Mittal Tubarão, almost 100 % is recycled !

Where about the problems concerning Iron and Steel production ?

1. High Capacity [Ladle of capacity of 400 t/Heat.

Blast Furnace with 12 000 t/day. LD Converter by 420 ton/Heat]

High Investment Cost

2000 USD/t Steel/Year [1stroute]

{For EAF this value could be highly reduced: USD 250 USD/t Steel/Year}.

This is one advantage for producing Sponge Iron !

It depends upon on Scrap Availability !

Where about the problems concerning Iron and Steel production ?

2. Memory Effect – Just for some years ago it has been in developping Steel

with the Memory Effect • [Article on USA – Mai 2009 – 1st in the Congress]

3. Main Characteristic of Iron: Corrosiv. – Effect of O2 and H2O is Thermodynamic unsustainable

4. Change on Market (Global Market) – Past P = C + W

– Now C = P – W P is defined by the Market

W comes from the Investor Then C ≤ CSteel plant

5. New process for developping

– Speed is low due to: – Normal route has high Efficiency

– Investiment is high

– Sector is not elastic like Computer Sciences (CS) – [In India, the Metallurgical Engineer are changing from Metallurgy to CS]

6. Energy is connected with CO2

– For the common process x Scrap Route

7. Challenge is using Non coking coal,

– Iron Ore with low Iron content and be economical, without CO2 generation

Where about the problems concerning

Iron and Steel production ?

The driving forces for evolution • Reduction of cost

– lower grade raw materials

– substitution coke – coal Biomass

– high productivity, efficiency

• Flexibility

– shorter routes

– fine ores, coals

• Quality of steel

– residuals

– C, N ; UBC

• Sustainability / Environmental aspects

– recycling

– treatment of by products

– emissions : dust, Sox, Nox, dioxines, VOC, CO2

Evolution of BF - BOF route

• Ironmaking

– Efficiency; reduction of number of Blast furnaces

– low cost: raw materials, energy

– preserve life time of coke plants and Blast furnaces

– environmental aspects at sinter plant

• BOF

– increased use of scraps : hot metal ratio 800kg/t

• Secondary metallurgy

– dramatic improvement of vacuum technology

– ultra low C, H, N, O, P, S steels ; C< 15ppm ; N < 20ppm

• large and highly integrated steel mills

• process driven by the products

– very high cold formability

– weight reduction

Biomass

Biomass

Evolution of the blast furnace technology

The rupture towards New frontiers keeping the counter current in the shaft

injection of partly reduced ores through the tuyeres

fulfillment of the local and global heat requirements

hot metal = counter current metal + injection metal

The continuous improvement

life time :

realistic objective : 20 years (KSC, CST, …) ; 12000 t/m3

coke consumption:

230 - 250 kg/tf coal ; 270 - 250 kg/tf coke (incl. small coke)

productivity :

70t/m²/d

hot metal quality :

sigma Si 0.1% ; S << 0.020%; S residuals < 0.05

Biomass

Biomass

Biomass

EAF route

• Iron sources

– scrap quality: scrap « purification » for controlling tramp elements

– shredding and sorting of E40 scrap : %Cu 0.45 down to 0.10

– beneficial effect of DRI or hot metal on the process

• Large room for EAF process improvement

– productivity

– use of fossile energy to improve melting time ; slag foaming

– post combustion

– development of air tight technology

– quality of steel : low C and N achievable; N: 40 ppm ; C: 0.04%

• mini mills, increasing use of secondary metallurgy

• access to flat products (automotive, packaging )

• good fit with thin slab casting

Biomass

Biomass

Science Technology

Technology

Charcoal Production

Technological Overview Solid Biomass Fuels

Wood logs and pellets

Charcoal

Agricultural waste

(Stalks & other plant debris)

Timbering wastes

(Branches, treetops & wood chips)

Animal wastes (Dung)

Aquatic Urban wastes (Aquatic plants Kelp &

water hyacinths)

Urban wastes (Paper, cardboard & other

combustible materials)

Direct burning Conversion to gaseous

and liquid biofuels

Gaseous Biofuels

Synthetic natural gas (Biogas)

Wood gas

Liquid Biofuels

Ethanol

Methanol

Gasohol

thermal chemical

biochemical

Biomass • Definition

Biomass is biological material derived from living, or recently living organisms. It most often refers to plants or plant-derived materials which are specifically called lignocellulosic biomass.

• Use of biomass

– As a renewable energy source, biomass can either be used directly via combustion to produce heat, or indirectly after converting it to various forms of biofuel

Conversion

Conversion of biomass to biofuel can

be achieved by different methods which

are broadly classified into:

1 thermal

2 chemical

3 biochemical methods

BioFuel and BioDiesel

Biofuels

Corn can be harvested to produce ethanol.

Unlike other renewable energy sources, biomass can be converted

directly into liquid fuels - biofuels - for our transportation needs

(cars, trucks, buses, airplanes, and trains).

The two most common types of biofuels are ethanol and biodiesel.

Sugarcane Bagasse

Sugar cane Plant -Sucrose: 30 %

- Leaves & Stem Tips: 35 %

- Bagasse: 35 %

Sucrose accounts for little more than 30% of the chemical

energy stored in the mature plant; 35% is in the leaves

and stem tips, which are left in the fields during harvest,

and 35% are in the fibrous material (bagasse) left over

from pressing.

Process production of Sugar and Ethanol

The production process of sugar and ethanol in Brazil

takes full advantage of the energy stored in sugarcane.

Part of the bagasse is currently burned at the mill to

provide heat for distillation and electricity to run the

machinery.

This allows ethanol plants to be energetically self-

sufficient and even sell surplus electricity to utilities;

current production is 600 MW for self-use and 100 MW

for sale.

Cost & Investment This secondary activity is expected to boom now that

utilities have been induced to pay "fair price "(about

US$10/GJ or US$0.036/kWh) for 10 year contracts. This is

approximately half of what the World Bank considers the

reference price for investing in similar projects.

The energy is especially valuable to utilities because it is

produced mainly in the dry season when hydroelectric

dams are running low.

Estimates of potential power generation from bagasse

range from 1,000 to 9,000 MW, depending on technology.

Comparison of Energy

Higher estimates assume gasification of biomass,

replacement of current low-pressure steam boilers and

turbines by high-pressure ones, and use of harvest trash

currently left behind in the fields.

For comparison, Brazil's Angra I nuclear plant generates

657 MW.

Presently, it is economically feasible to extract about 288

MJ of electricity from the residues of one ton of

sugarcane, of which about 180 MJ are used in the plant

itself. Thus a medium-size distillery processing 1 million

tonnes of sugarcane per year could sell about 5 MW of

surplus electricity.

Yield Increasing At current prices, it would earn US$ 18 million from sugar

and ethanol sales, and about US$ 1 million from surplus

electricity sales. With advanced boiler and turbine

technology, the electricity yield could be increased to 648

MJ per tonne of sugarcane, but current electricity prices do

not justify the necessary investment.

Source: According to one report, the

World Bank would only finance

investments in bagasse power

generation if the price were at least

US$19/GJ or US$0.068/kWh.

Environmental Advantages Compared with Coal

Bagasse burning is environmentally friendly compared

to other fuels like oil and coal. Its ash content is only

2.5% (against 30–50% of coal), and it contains very

little sulfur. Since it burns at relatively low temperatures,

it produces little nitrous oxides.

- Less Ash

- Less SOx& NOx

Other Advantages

Moreover, bagasse is being sold for use as a fuel

(replacing heavy fuel oil) in various industries, including

citrus juice concentrate, vegetable oil, ceramics, and tire

recycling.

The state of São Paulo alone used 2 million tonnes,

saving about US$ 35 million in fuel oil imports.

Researchers working with cellulosic ethanol are trying to

make the extraction of ethanol from sugarcane bagasse

and other plants viable on an industrial scale.

Closing Remarks

• We can see that all wastes generated in the Agriculture in Brazil can be converted in Energy

• Brazil can substitute may be more than 40 % of Energy based upon on the profit of Wastes generated in the Farms

• We can reduce the import of coal by using more wastes from the Agriculture in the Ironmaking & Steelmaking

Case Study

Use of sugar cane bagasse and charcoal mixture for injection into the tuyeres of Blast Furnace aiming the CO2 Emissions

Reduction of the Steel Segment

Prof. Dr. Paulo Santos Assis - UFOP/Brazil

Prof. Dr. Danton Heleno Gameiro - UFOP/Brazil

Dipl-Ing. Janaina Solvelino Brum-UFOP/Brazil

Presenter: Prof. Dr. Suleimenov – Kazakhstan

BHU / India

Introduction

Steel production in Brazil is by 35 Million tons

1/3 is produced using Charcoal

Biomass can be injected into Charcoal Blast Furnaces

Advantagens considering GHG Emissions

Overview

Objectives

Study the possibility of injection of Sugar Cane Bagasse mixed with Charcoal into Small Blast furnaces.

Determine the combustion rate of the selected mixtures

Methodology

Grinding the bagasse

Sample: 30 kg Sieving

Classification

Fixed carbon and volatiles materials determination.

A sample < 150 # determination of Calorific Power Value.

Classification

Sugar Cane Bagasse

Methodology

Calsete Ironmaking

Gusa Nordeste Four samples

A sample – 150g Identification

(C1, C2 e C3) – Carbon Fix

(G1, G2 e G3) – Grain Size Distribuition

(U1, U2 e U3)- Moisture

(AP) – Elementary Analysis

Charcoal Characterization

Mixtures preparation for the Combustion Test

Methodology

% Charcoal % Sugar Cane Bagasse

100 0

80 20

60 40

40 60

20 80

0 100

Simulation of Injection rate: 50, 80, 140 kg/ton Hot Metal

HGTS- High Gradient Thermal Simulation

Methodology

Methodology

Esquema da queima realizada no simulador de gradiente térmico

Injection Powder Process

Time schedule for combustion trial

1st Photo: 40 ms before 2nd P: In the moment 3rd P: 20ms after

Gas Analysis – ORSAT Equipment

Methodology

Carbon monoxide – CO

Carbon Dioxide – CO2

Oxygen – O2

Combustion rate determination

Methodology

TC = {(%CO + %CO2)*n / [(ma*%Cf / 1200000) – (%CH4*ng / 100)]}*100

where:

TC = combustion rate (%);

%CO, %CO2, %CH4 = Produced Gas in vol. percentage;

%Cf = Fixed Carbon in the Sample;

ng = Gas Mols number produced;

ma = Biomass of materials injected in mg.

Results

Preliminary results characterization of sugarcane bagasse powder

Parameter Grain Size

[% < 200#]

Density

[kg/m3]

Fixed Carbon

[%]

Volatile

[%]

PCI

[kcal/kg]

Value 80 195 16,46 78,28 2.095

Results

Representation of chemical analysis and particle size of charcoal

Sample Proximate Analysis; Dry Basis Elemental Analysis Avarage of grain

size [mm] Cf

[%]

TU

[%]

MV

[%]

CZ

[%]

C

[%]

H

[%]

N

[%]

O

[%]

C1 54,8 1,4 24,2 21,0 0,070

C2 59.6 1,4 24,6 15.8 0,072

C3 65.3 1,4 24,1 10.6 0,068

U1 59.6 1,1 24,6 15.8 0,070

U2 59.6 2,9 24,6 15.8 0,072

U3 59.6 4,8 24,6 15.8 0,070

G1 60,1 1,5 24,4 15,5 0,070

G2 59,8 1,5 24,3 15,9 0,119

G3 60,9 1,5 24,4 14,7 0,162

AP 60,1 1,6 24,2 15,7 66,67 2,54 0,81 29,98 0,073

Parameters results of porosity and bulk density of charcoal

Results

Sample Specific

Surface

Total

volume

of pores

Micropore

volume *

(θm <2ηm)

Area of

micropore

*

Average

pore

diameter

Size of

pores

Density

Unity m2/g 10-

2cm3/g

x10-3cm3/g m2/g Ǻ Ǻ g/cm3

C1 1,861 0,5804 0,7991 2,262 120,48 2918,6 1,512

C2 1,729 0,6945 0,7995 2,264 160,07 1342,8 1,504

G1 1,367 0,1143 0,7453 2,110 330,44 1795,4 1,597

G3 2,171 1,086 1,0119 2,885 200,00 1466,8 1,539

AP 2,442 1,102 1,057 2,993 180,05 2278,1 1,555

Results of combustion rates as a function of charcoal percentage

in the mixture and the injection rate of mixtures (kg / t HM)

Results

Charcoal + Sugar Cane Bagasse

Charcoal

(%)

Bagasse

(%) 50 kg/tHM 80 kg/tHM 140 kg/tgHM

0 100 86 85,1 78.0

20 80 87,2 87.5 81.3

40 60 90.2 88.6 83.5

60 40 93.3 92.7 88.7

80 20 95.1 94.8 88.7

100 0 94.8 93.2 87

Results

75

80

85

90

95

100

0 20 40 60 80 100

Bagaço na mistura (carvão vegetal + bagaço) [% peso]

Ta

xa

de

co

mb

us

tão

[%

]

50 kg/tgusa 80 kg/tgusa 140 kg/tgusa

Effect of bagasse in the mixture on the combustion rate.

Results

75

80

85

90

95

100

40 60 80 100 120 140

Taxa de Injeção [%]

Ta

xa

de

Co

mb

us

tão

[%

]

Carvão Vegetal 100% Bagaço de cana-de-açúcar 100%

Effect of injection rate of charcoal on the combustion rate for two

extreme situations: 100%charcoal and 100% bagasse.

CONCLUSIONS

•There is an increase of combustion rate when mixed

sugarcane bagasse with charcoal;

•There is an increase in combustion rate when you put up

20% of sugarcane bagasse in the mixture;

•An increase in injection rate implies a reduction in the

rate of combustion for the two fuels;

•Increases from 50 to 80 kg / t hot metal practically do not

change the combustion rate, however when it goes up to

140 kg / tgusa, there is a reduction in the combustion rate

• From the point of view of the combustion in front of the

tuyeres is technically feasible the injection of a mixture

with charcoal and sugarcane bagasse;

•From the environmental point of view it is possible

through the use of this mixture reduce the emission of

CO2 in the atmosphere, ie, the hot metal production of

may be more sustainable comparing with only charcoal

use in the Blast Furnace;

•The development and application of new technology

are in line with the concept of Socio Economic

Environmental Sustainability.

CONCLUSIONS

• To UFOP- Escola de Minas

• To CNPq and FAPEMIG

• To Gorceix Foundation

• To Prof. Suleimenov that gave us time to prepare and

to present this Technical Contribution

.To Prof. Gupta that invited us for this Contribution

All of you for kindly attention !

Acknowledgments

Thank you!

55

Paulo Santos Assis

assis@em.ufop.br

Photo of Escola de Minas, at night in Ouro Preto

Prof. Dr. Paulo Santos Assis assis@em.ufop.br

Thank [English]

Vielen Dank [Deutsch]

Спасибо [Руссо]

谢谢 [中国]

धन्यवाद [ ह िंद ू]

ありがとう [日本人]

Obrigado [Português]