Energy saving and environmental protection in Chinese Steel Industry (a typical process industry) Activity 3.2

Transcription

1 Energy saving and environmental protection in Chinese Steel Industry (a typical process industry) Activity 3.2 Daqiang CANG School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Key Lab of Ecology and Circle Metallurgy, Ministry of Education China Contract number: CN/ASIA-LINK/016(103 LINK/016( ) 187) 1

2 Content 1. Preface 2. Chinese steel industry 3. Present situation of energy consumption in Chinese steel industry 4. Environmental protection in Chinese steel industry 5. New tech. on Energy Saving & Environmental Protection for steel industry 6. Conclusions 2

3 Steel industrial process Power generation Gas Coking BF LD CC Hot rolling Cold rolling Wasted plastic Slag Scrap Sintering Cement Products 3

4 1.Preface * Steel still is the main material, but is a energy intensive and heavier polluted industry. * A huge domestic market in China. * Some gap between China and the others: 4

5 2. Chinese steel industry Production of crude steel: 420 million tons, 2006(~1/3 of the world). 18.5% increase comparing to Domestic crude steel consumption: 384 million tons, 2006, 30.98% in the whole world. 5

6 China Steel Output In Recent 5 Years Outp ut( tons) Steel output 6

7 China steel output in the past 16 years 7

8 The Characteristics of Chinese steel production, 2006 The structure of Chinese steel products changed. The production and proportion of high- level products increased. The production of special-purpose purpose steel products increased. 8

9 Some steel products adjusted in 2006 Class Output (10000 tons) Growth proportion High-level products plate Cold rolling sheet % 53.1% Container plate % Specialpurpose products Bridge plate Shipbuilding plate % 34.8% Stainless steel % 9

10 New policy Chinese steel production Change the steel industry from big size to higher level. Improve the technology and hardware. Increase the proportion of high-level products. Strengthen steel enterprises centralization and reorganizing. 10

11 3. Present situation of energy consumption in Chinese steel industry Pictures from Baosteel,, Shanghai, China 11

12 Energy consumption in 2006 Gross energy consumption: 198 million tons ce (standard coal),increased 15 million tons ce than 2005,about 8.45%(production:18.5% increased). Comprehensive energy consumption : kgec/t,reduced 7.06% than Comparable energy consumption : kgec/t,reduced 6.19% than Fresh water consumption: 6.56t/t,reduced 14.9% than

13 The energy consumption between 1990 and 2000 (The data after 2000 are from large and middle sized steel enterprises ) amount of energy consumption,0.01million tec nationwide energy consumption,0.01million tec total energy consumption of iron and steel making industry,0.01million tec energy consumption of steelmaking industry /nationwide energy consumption,% energy consumption of steel making/nationwide energy consumption,% year 13

14 The constitution of energy consumption in Chinese steel industry, 2004 Naturalgas,0.50% Fuel oil,3.02% Electricity power,26.40% Coal, 69.90% 14

15 Steel industry energy structure in some countries China USA Germany Japan Coal 69.9 % 60 % 55.8 % 56.4 % Fuel oil 3.2 % 7.0 % 20.7 % 19.9 % Natural gas 0.5 % 17.0 % 8.2 % Electricity power 26.4 % 16.0 % 15.3 % 23.7 % 15

16 Year Comprehensive energy consumption Comparable energy consumption Sinter Iron making Cocking LF EAF Rolling The variation quality of 2005 to Change rate -20.3% -8.6% -5.9% -2.0% -11.2% 25.8% -24.3% -25.0% Changes of the process energy consumption in 2000~2005 (kgce/t) 16

17 Comprehensive Energy Consumption/t steel Comparable Energy consumption/t steel Cocking Sinter Iron making LF EAF Rolling Key enterprises (kgce/t) Advanced level (kgce/t) Lagging indicator (kgce/t) The gap between advanced and average,% The gap between lagging indicator and average,% The energy consumption gap between steel enterprises in ChinaC 2005, (kgce/t( kgce/t)

18 Process Sintering Pelleting Cocking Iron making LF EAF Power Rolling The domestic key enterprises Baosteel (first season) O International advanced level(1999) Hot-rolling47.82 Cold-rolling80.28 The proportion of total energy consumption(%) 约 The gap between China(2005) and international advanced level(1999) l(1999) (kgce/t) 18

19 Some new energy saving technology applied in China There are more and more energy saving tech. were used in Chinese steel industry, the following are some of them which start to be used in the past few year. (1) Coke Dry Quenching (CDQ) 1) Recovery sensible heat from red coke : 80% 2) Produce 0.5t/t,steam pressure: 4MPa, ) Improve environmental quality. 4) Improve coke strength, with M40 increase 3~8%, M10 reduce 0.3~0.8%. 0.8%. 19

20 (2) Heat Recovery Technology from Hot Sinter product for Steam and electricity generation Recovery 76kg steam /per ton sinter product in Baosteel eel. (3) Blast Furnace Top Gas Pressure Recovery Turbine Unit (TRT) which can generate 37kwh electricity/ ton of product in Baosteel. 20

21 (4) HTAC (High temperature air combustion) Fuel oil Hot air 1000 o C Burner nozzle A Burner nozzle B Fuel oil High temperature gas Temperature 1200 o C Left regenerative chamber Cold flue gas<200 o C Left regenerative chamber Rom temperature air Directional control valve 21

22 4. Environmental protection in Chinese steel industry (for gas, solid, liquid phase pollutants) 22

23 The proportion of the pollutants of Chinese steel industry to the gross national pollutants Based on the data of the National Bureau of Statistics of China, The proportion of the steel industry pollutants to the national total pollutants are as follows: 23

24 Gross National emissions Steel industry emissions Proportion (%) Waste gas (cubic meters) SO2 (10 thousand tone) Smoke (10 thousand tone) Dust (10 thousand tone) Waste water (10 million tone) The proportion of the steel industry pollutants to the gross national pollutants 24

25 Index (statistic incompletely) Reused industrial water (%) New water consumption per tone steel (cubic meters) Outfall waste water capacity per tone steel (cubic meters) Waste water disposing ratio (%) The ratio of disposed water (%) Utilization ratio of the coking gas (%) Main indexes of environmental protection and pollutants utilization in main steel enterprises recently 25

26 Index (statistic incompletely)% Utilization ratio of the blast furnace gas (%) Utilization ratio of the converter gas (%) Utilization ratio of the dust and sludge (%) Utilization ratio of the waste dregs (%) Utilization ratio of the furnace slag (%) Utilization ratio of the steel slag (%) Utilization ratio of the waste acid (%) Converter slag Sulfuric 76 Hydrochloric 98 26

27 The major problems of environmental protection for Chinese steel industry.(1) Wasted water from coke making process (2) SO 2 and NOx in Sinter flue gas (3) High temperature dedusting (4) Dioxin remove from sinter plan (5) Organic pollutant remove from water (6) BOF and EAF slag utilization (7) Tailing from iron ore mine 27

28 The goal of energy saving and environment protection after the tenth five-year year-projects. Several important target of clean production in large and middle-size enterprises in 2005 and 2010 Year 1million t/a coke oven dry quenchin g proportio n (%) BF over 1000m 3 TRT proportio n (%) New water consump tion per tone steel (m3) Proporti on of converte r gas utilizatio n (%) Waste water and gas standardi ng rate (%) Decrease of main pollutant discharg e amount (%) Compreh ensive energy consump tion per tone steel (kg/t) (BF between 300 to 1000m 3 TRT proportio n)

29 Strengthen the Environment Impact Assessment Minimizing pollutant Improve the energy utilization efficiency Improve the water utilization efficiency Improve the material utilization efficiency 29

30 Some concerned activities in China: The principle: Cleaner production (CP) Recycle economy (RC) Industrial ecology (IE) 3R : Reduce, Reuse, Recycle From the resource side minimizing the pollutant emission, energy consumption and resource consumption. 30

31 5.New technologies and approaches New approaches for energy saving: (1)process innovation: Continuous casting instead of model casting, etc. (2) short process instead of long process. (3) small size ---large size enterprises. (4) develop more super steel products. (5) industrial ecology (industrial group system). 31

32 New approaches for environment protection: (1)Treat wastes before process, in process and after process. (2)Waste treatment with wastes. (3)Industrial ecology: use wastes as a new resource (for another industry or enterprise). 32

33 New tech.: For energy saving: (1) Low temperature,dispersed, batch emitted wasted heat for power generation. (organized a national symposium in China) (2) Energy saving materials development : Nano fluid, nano coating, copper stave for BF (3)Physical fields to change the chemical and physical properties or the process (patens). (4) Super-critical conditions for new energy production. (5) High temperature slag heat recovery. 33

34 New tech. for environment protection: (1)In process control (not end of pipe control): e.g. fixed SO 2 in solid sinter product, not in flue gas etc). (2) Slag reform: change crystal structure and composition for new application etc. (3) High temperature dedusting (4) H 2 metallurgy (5) Water saving (6) Waste treat waste: coking wasted water treats SO 2 in sinter flue gas and 34

35 Conclusions 1) Different countries have different conditions and requirement under different developing stage, some tech. be used maybe different in different countries. 2) Recycle economy is a good way for energy saving, environment protection and resource utilization effectively. 35

36 Many thanks! 36