In year of 2002, Anshan city became the Second " National Sanitation City" after the First one of Dalian City in Northeast of China. The expert in China Patriotic Health Campaign Expert Conclusion Committee pointed: " Anshan Iron and Steel Group (Angang Group) made a very good connection between the enterprise revamping and the all--round control of the whole city environment. It increased efficiently the comprehensive prevention ability of the city pollution and the city function and make an outstanding contribution for the city to establish the work to be the national sanitation city and the increasing of the city comprehensive sanitation level."
Since the "Ninth Five—Year Plan", Angang Group made the large—size of technical revamping work according to the requirement of walking on the way of new type of industrial road to look for the further potential of energy—saving and consumption—decreasing, strengthen the pollution prevention, utilize the "three wastes" reasonably, carry out clean production, and take a way of energy –saving, consumption—decreasing, utilization of wastes, self—improving and well—cycling. The development of the enterprise makes a historical new breakthrough and got a very high appraise as " new face taking the place of old view". All the product of steel in Angang Group got the certificate of ISO 14000 Environmental Management System. The enterprise has been awarded with Garden Plants of Liaoning Province.
1. Clean out the backward production processing and technical equipment by means of technical revamping.
Normally the old enterprise is always with high energy—consumption, terrible pollution and poor marketing competition ability. It is closely related with the backward technical equipment and the production processing. The appearance of Angang Group in nine (9) years before was with the following features:
•More furnaces and fewer converters. The output of steel made with the furnaces was 62.1 5 of the total amount, the metal recovery ratio could only get to 80%, large energy consumption and terrible pollution.
•More modeling casting + Primary Rolling, less continuous casting. Modeling casting + primary rolling was 70 % of the entire process, poor quality, high-energy consumption and heavy pollution.
•Backward equipment. Among the equipment of the production, the equipment with backward or clean—out occupied 80%, and the semi—continuous mill that produced nearly half of the total output of steel section was the equipment provided by the ex—Russia during the time of 50's in the Twenties Century.
•Lower Grade of the Product. The product that could get to the international level was only 6 %, and 69% of the product could get to the national standard level. The backward product was 25%.
•Unreasonable structure of the product. Less plate section or tube section. They were only 40% of the total; the bar section was 60%.
•More primary level and less further processing product. There were 2 million tons of slabs, and 4.8 tons of primary section, 900,000 tons of cold mill plate and 0 ton of color coated sheet.
In this case we can imagine that the enterprise problems with high energy—consumption and the heavy pollution could not be solved without increasing the strength of technical revamping. Otherwise the marketing competition could not be increased very easily.
Since "Ninth Five—Year Plan", Angang Group has kept utilizing the high and advanced technology and the applicable technique to make the revamping work for the traditional production. The new road of "Higher Starting Point, Less Investment, Quicker Output and More Profit" is the technical revamping way for the old enterprise. This way not only increases the level of the product, improves the variety structure, enlarges the production size and makes Angang Group as the second " ten thousand tons of output" iron and steel enterprise, but also makes the energy—saving, environmental protection and achieves the " double increases" of both the economic profit and social benefit.
1) The technical revamping projects during the " Ninth Five—year Plan" Period and the result of the energy—saving and the environmental protection
During the " Ninth Five—Year Plan" period, firstly we focused on the revamping work of the main final production processing flow part of well steel making and well rolling mill. During the " Ninth Five—Year Plan", the investment of the environmental protection was 930 million Yuan and this investment was 7% of the total technical revamping investment for the " Ninth Five—year Plan".
•For the blast furnace, the new technique of coal blowing was used for energy—saving and consumption—decreasing. We utilized technique of the basic—speed grinding and fine power coal collection with one machine. This technique increased the coal blower ratio of the blast furnace further more and decreased the amount of the coke into the furnace. The coke ratio into the furnace in 2002 decreased by 87 kg / t than the one in 1995. In this case, it decreased the production of the dust and the sulphur dioxide and it also saved the energy.
•Clean out the process of furnace and the entire process of steel—making was with converter. The feature of steel—making with furnace is high energy—consumption, low profit, and terribly heavy pollution. Especially the secondary dust and smoke going out of the workshop affected the quality of the air terribly. We cleaned out 5.30 million tons of furnace steel and built 6 sets of modernized converters. The steel—making with converter will decrease the cost by 95 Yuan per ton comparing with steel—making with furnace. Since this project utilized some new technology like secondary dust collection, bulk material screening, new—type of oxygen gun positioning structure, and all the basic parameters such as the parameters of oxygen gun, weighing, boiler and dust and smoking cleaning etc. were controlled by the computer. 2.65 billion of cubic meters of out—going air wastes were decreased per year. 18 thousand tons of dust drainage was decreased. Therefore, the pollution of steel—making was under the permanent control. For example: After the converter took the place of the furnace for No.2 steel—making works, the energy—consumption was decreased greatly and the environmental protection profit was very obvious. The steel output of this Works was increased from 2.75 million tons / year before the revamping to 3.26 million tons / year in 2002. However, the total energy—consumption was decreased by 52.9 %, and the fuel—consumption was decreased by 52.6%. The dust and smoke (ash) in this Works is decreased 89.5% per year, the sulphur dioxide was decreased by 91.1%; and the solid wastes comprehensive utilization gets to 100%.
•Clean out the modeling casting, and make the completely continuous casting in process. The process of modeling casting is with high energy—consumption, poor profit, and serious pollution. The proportion of continuous casting in Angang Group in 1994 was only 24.88%. At the end of 2000, the entire line was with continuous casting process. Comparing with the modeling casting, the cost of continuous casting can be decreased by 200 Yuan per ton. For the process of continuous casting project, we utilized the technology like roll gap automatic monitoring and measuring and the roll line with fine rollers, multi—point bending and multi—straightening, air—mist secondary cooling, hot charging and hot discharging for the continuous casting bloom etc. In this way, the polluted material drainage was decreased greatly. In No. 1 Steel—making Works, the dust and the smoke (ash) and the sulphur dioxide total drainage amount was respectively decreased by 1058.88 tons and 1620.09 tons per year by means of the measurements like increasing the continuous casting ratio, parts of continuous casting slabs with high temperature hot charging rolling, revamping the production process, decreasing the waste drainage and the steel—making energy—consumption in the sequence, cleaning out the backward production equipment etc. After the entire line was with complete continuous casting process in this Works, the ex—silicon sheet Works, the Primary Rolling Mill with high energy—consumption and wastes drainage, the ex—small size of No. 1 workshop etc were cleaned out. 86,700 tons standard coal of consumption was decreased among the annual total energy—consumption.
•Three short—circuit processing flow production lines with the international first—class were built. 1780 hot strip mill production line was with the latest and most advanced hot strip mill technology including energy saving and environmental protection technology. 1700 continuous casting and continuous rolling mill production line is a short processing flow line composed of the sheet slab continuous caster, two stepped reheating furnaces, two sets of roughing mill stands and six finishing mill stands. Because a series of international advanced processing technology such as the advanced short processing flow compact layout, hot discharging and directly charging technology etc. are used in this line, the energy—consumption, material—consumption and all kinds of pollution drainages are decreased greatly. in 2002, the fuel consumption was decreased by 23,000 tons of standard coal / year comparing with the consumption before the revamping work.; the drainage of the waste water was decreased by 2.16 million tons and as a matter of fact, the drainage of the waste water is zero.
The acid pickled—mill stand combined unit utilized the hydrochloric acid process to take the place of sulphuric acid one and this process was combined with the five sets of mill stands to make an acid pickled –mill stands unit. In this way, it not only decreased the pollution material and the wastewater drainage amount during the processing, but also increased the product quality and the production ability. It saved the energy, decreased the consumption and decreased the pollution too. In 2002, the unit consumption of the acid pickled—mill stands combination unit was decreased by 76.8 kg standard coal / ton of steel comparing to the one before the revamping work.
2)The technical revamping projects during the " Tenth Five—year Plan" Period and the result of the energy—saving and the environmental protection.
Under the condition with pay—back of the entire investment for the " Ninth Five—Year Plan" projects and the accumulated capitals, during the " Tenth Five—year Plan" Period, the revamping for the before iron--making and after rolling was done to improve the technical process before the iron—making and improve the further processing ability of the steel section.
•In the mine, the revamping for increasing the content of iron and decreasing the silicon content was done. The grade of the iron into the furnace in 2002 was increased by 3.5% comparing to the one in 1995. Each percentage point increased for the iron grade into the furnace will decrease the slag amount by 30—40 kg / ton of iron and 50 % of gas ash of the blast furnace. After the revamping project for increasing –iron and decreasing—silicon, the iron consumption for the blast furnace was decreased by 99 kg / ton of iron.
•Clean out the hot sintering process, and make the cold sintering product ratio with 100 %. 8 sets of 90 m2 sintering machines with hot sintering ability of 15.61 million tons altogether were cleaned out and two sets of 360 m2 sintering machines were built to produce the sintering product. It not only optimized the charging material structure in the blast furnace, but also made the dust drainage amount decreased by 78.2 % per year.
•New No.1 Blast furnace project. After the New No.1 blast furnace with 3200 m 3 was put into production, it not only made the technical equipment for the iron—making system in Angang Group get to the advanced level in China, but also made a permanent control of the problem of iron—making causing the environment pollution. This project utilized the latest advanced technology home and abroad, firstly, in the production process, it is with high efficiency, good quality, energy—efficiency and decreasing pollution and this made the index for material—consumption, energy—consumption and water—consumption get to the advanced level home and abroad; we also took the reliable and perfect final end of control measurements to do the control for the entire processing pollution and make the output—increasing and pollution—decreasing. The major clean production technology we utilized include: entire computerized automatic control, trained cage eccentric discharging type of bell—less top of blast furnace, high—pressure operation technology, power—generating technology with the extrapressure on the top of the blast furnace, blast furnace rich oxygen coal blowing technology, extraheat utilization technology of the hot stoves, high air temperature operation technology, sintering product graded to charge into the blast furnace, the recovery of the small –piece of coke and the new technology of mix—charging of iron into the blast furnace, INBA slag granulation treatment technology, new technology of end control and water—saving technology etc.
•Two sets of 55—bore 6—meter coke oven and equipped dry—extinguishing coke project. No. 1 coke oven will be put into production in October of this year and No.2 coke oven is planned to put into production in December of this year. The dry—extinguishing coke project is scheduled to put into production in 2005. At the same time, we will equip dust collectioning of coke oven charging and coke pushing to control the dust of the coke oven and the poisonous and harmful dust. The environmental protection equipment of the coke oven will decrease the dust by 896 tons per year, 170 tons of poisonous and harmful air such as sulphur dioxide etc; the environmental protection equipment of the dry—extinguishing coke project will decrease the dust by 912 tons per year and 350 tons of poisonous and harmful air such as sulphur dioxide etc.
•Short processing flow of high—speed heavy rail production line. This production line is the first short processing flow of high—speed heavy rail continuous casting and continuous rolling mill production line home and abroad. We imported the rail universal mill from SMS in Germany and the international advanced level of horizontal and vertical combined straightener and four—end straightener. The production line not only has the ability to produced high—speed and high strength heavy rail of 50 meters long and 300 kilometers / hour, but also can produce H section of steel product with middle and small size and this increased the competition ability of the section steel in the market for Angang Group. Since it was put into the production, the unit consumption of this production line was decreased by 7 kg standard coal / t of steel and 7.5 tons per ton of steel for new water consumption comparing to before the revamping. The new water consumption is zero.
•The revamping work of central power—station boiler in No. 1 Power Works. The 220 tons / hour pure combustion of blast furnace gas boiler is scheduled to take the place of the present 11 sets of oil and coal fuel small boilers. This will decrease the dust by 10,000 tons / year and 4800 tons / year of sulphur dioxide. No. 1 boiler is planned to put into production at the end of March next year and the No. 2 boiler is scheduled to put into production in June next year. For this project, the recovery of blast furnace gas per hour will be 200, 000 cubic meters. And 105,800 tons of standard coal will be saved every year.
Since the " Ninth Five—Year Plan", all the energy—saving environmental projects that have been carried out have achieved very obvious result. The energy consumption of unit steel was decreased by 13.6% in 2002 comparing to in 1997, and the new water consumption of unit steel was decreased from 29.5 tons before to the present 16 tons. The industrial dust and smoke drainage in 2002 was decreased by 34% comparing to in 1995.
2. The reasonable utilization of the industrial " Three Wastes".
Since the " Ninth Five—Year Plan", Angang Group has established more 40 " three wastes (wastewater, waste smoke, waste slag) comprehensive utilization projects such as slag development, fully recovery of the gassy slurry and converter gas, recovery utilization of the extra heat and water resource, powder metallurgy and construction material. The industrial " three wastes" is treated with resource utilization.
1) Increasing the waster resource utilization ratio
•The biggest wastewater treatment Works of China in western ditch was established. The daily treatment amount is 220,000 tons and the water quality after the treatment gets to the standard of clean water circulation. The daily recovery circulating water is 168,000 cubic meters.
•Revamp and improve the wastewater treatment Works in northern ditch. The daily treatment ability is increased by 40,800 tons.
•In the Heavy Plate Mill Works and the Rod Section Works, the falling—down water after the rolling recovery project was carried out. This made zero drainage of the "wastewater". In the heavy plate mill works, the falling down water was decreased by 400 m 3/ hour, and in the rod section works, it was decreased by 180 m 3/ hour.
•Revamp the biological wastewater treatment system of the General Chemical and industrial Works. The measurement of nitrogen and ammonia treatment was taken. At the present it is under the construction. After the project is put into production, it will make the content of nitrogen and ammonia in the water decrease by 245 milligram / liter, and the water after the treatment can be used for other multi—application such as dust collection etc.
In 2002, the output of steel got to 10.0665 million tons and it was increased by 17.03% comparing to in 1996. But the total water consumption was decreased by 12.96%; and the wastewater drainage amount was decreased by 51.1 %. At the present, the water circulating utilization ratio gets to 91 % and the new water consumption of unit steel is decreased greatly.
2) Utilize the secondary resource efficiently and decrease the air pollution
•In No. 1 steel—making works, the steel—making was done with minus energy. In January and February of this year, the energy consumption of NO. 1 steel—making works was 32.85 kg / ton of steel (the steam recovery was 15.45 kg / ton of steel, and gas recovery was 20.32 kg / ton of steel), the recovery of secondary energy was more than the energy consumption of steel—making with converters and this is what we called minus energy steel—making. This index in China was in the top level of the similar converters.
•One set of converter gas recovery system with 80, 000 cubic meters was established. The converter gas recovery in No. 1 and No. 2 steel—making works was done and used for the reheating furnaces in 1780, 1700, medium sheet and middle size of rolling mill sequence and this ended the history of converter gas releasing of Angang Group. It not only saved the energy equivalent to 46,700 tons of standard coal / year, but also decrease the air pollution caused by the gas releasing combustion. The annual economic profit is more than 20 million Yuan.
•The differential pressure of No. 11 blast furnace gas was utilized for generation. One new set of TRT extra pressure generation system was built. And in 2002 the generation amount was 33.75 million KW and it is equivalent to saving 5734 tons of standard coal / year. The annual economic profit is more than 17 million Yuan.
• The project of heavy oil fuel taken placed by gas fuel was done. The oil fuel was changed with gas for the reheating furnaces in heavy plate mill works, rod section works, seamless tube works and Lingshan Forging Works and two sets of limekilns in the refractory corporation. This decreased the heavy oil fuel consumption and efficiently decreased the environmental pollution. The annual comprehensive economic profit was more than 100 million Yuan.
3) The circulation utilization of the solid wastes
Large amount of solid wastes are produced with the production processing of iron and steel enterprises. These solid wastes pollute the environment and occupy the field. If they could be circulated to use, then the wastes can be changed to source and energy. This not only can decrease the environmental pollution, but also can increase the economic profit.
•Treatment production for the steel slag. 240 tons of steel slag treatment production line imported with German technique will make a treatment to the steel slag with iron—concentration. The steel slag with concentrated high grade of iron will be sent back to the raw material production system. This will save 150,000 tons of sintering material each year. This production line not only makes 100 % of treatment for the new slag steel, but also makes the treatment for the piled slag for years.
•The project of fine slag powder. One production line of fine slag powder production line with annual output of 600,000 tons was established. The annual profit gets to 24 million Yuan. At the same time, one slag cement production line of 450,000 tons of annual output was established as well. The annual profit gets to 10 million Yuan.
•Corporate with Jidong Cement Co. Ltd to establish cement clinker aggregate production line of joint venture. In this line, we utilized 1.4 million tons of cement clinker aggregate with the generation dust ash, limestone screen underflow and slag etc as the raw material.
With the measurements mentioned above, slag, blast furnace slurry, converter slurry, rolling mill slurry and the material with iron content etc. were circulated to utilize. The utilization ratio gets to 89.1%.
Since the " Ninth Five—Year Plan", Angang Group has established 1109 sets of environmental protection facilities. Among them, there are 904 sets of smoke and dust treatment facilities, 87 sets of water treatment facilities, 87 sets of noise treatment facilities, and 31 sets of other facilities. Under the condition of steel output increasing, the amount of industrial smoke (dust) --releasing, oil pollution material in the drainage of wastewater and the suspending material drainage were decreased year after year. In 2002, the industrial smoke (dust)—releasing was decreased by 54,000 tons comparing to in 1995, 10,000 tons of sulphur dioxide was decreased, and the oil pollution material and the suspending material drainage was respectively decreased by 34.5 % and 52.2 %.
3. Ecological environment recovery and rebuilding
1) Mining Replanting
Angang Group owns 6 large—size of mines and has the production ability with 33 million tons of annual iron ore. Because of long time of mining, more than 2500 hectares of rock removal field and more than 1700 hectares of tailings dam were formed all—round the city. In order to prevent the soil erosion, decrease the effect to the environment and make the continuous development, Angang Group developed the mine and replanted it according to the spirit of " Mine Replanting, tree planting, mine beautifying and happiness creation for the young generation".
• The yellow mud after the stripping of the rock was used for covering on the top of the rock removal field. The average thickness of the yellow mud is 3 meters.
• Planting trees. Till to the end of 2002, the replanting and greening area has been finished with 155 hectares and 600,000 trees have been planted.
By the way of replanting, the ecological environment has been protected and the enormous social profit was created and this also became the new economic increasing point of the mine. The fast—speed poplar trees that have been planted could make a direct economic profit of 23 million Yuan per year with the calculation format as 400 Yuan / m3.
2) The greening and beautifying of the site of plant
• With the comprehensive control, from 1999 till to now, the new increasing greening area is 2.112 million m2 and there are 34 gardening greening land inside of the plant site with more than ten thousand square meters.
•Aiming to various pollution sources, we planted different kinds of arbor trees and bushes to improve the all—round environment. For example, we planted 1.37 million arbor trees such as pagoda trees and ginkgo (tree of heaven) that are anti—sulphur dioxide, dust prevention, and anti—chlorine etc. we planted 8.849 million bushes such as lilac, chrysanthemum etc. that could prevent from sulphur dioxide, dust and smoke, hydrogen fluoride etc.
•Greening the Slag hills. On the slag hills, the new increasing greening area gets to 350,000 square meters and 100,000 arbor trees and 210,000 bushes have been planted. The small regional greening ecological environment has formed.
At the present, the total area of greening land gets to 8.016 million square meters and the greening-covering rate reaches 33.4 %. This number is 12 of percentage points more than in 1998. In May of 2000, Angang Group was awarded with Gardening Plant in Liaoning Province.
With the development of greening, beautifying and replanting of the mine, the view of the plant site and the mine environment around of the city have been much more improved. Right now the present greening plants in the plant site could restrain the dust of 1560 tons / year, absorb 8064 tons of carbon dioxide each year and releasing oxygen of 8240 tons / year. This made the air quality of Anshan city improve a lot.
4. Develop the cycling economy
The cycling economy is basically a kind of ecological economy with continuous development. It requires restructuring the economy system according to the natural ecological system material cycling and the energy flow principle. The purpose for it is to make the economic system to be melted with the material cycling process of the nature ecological system in harmony.
With the revamping work and the development of the " Ninth Five—Year Plan", Angang Group owns the basis of developing cycling economy in principle. In 2002, the government of Liaoning Province approved Angang Group as the sample enterprise of developing the cycling economy. Angang Group has made up and carried out the " General Schedule of Constructing the Cycling Economy Sample Enterprise" to establish a cycling economic enterprise in 2010.
1) " 3 R" Principle of cycling economy
•Reduce: Reduce the resource of beginning and the target is to reduce the material amount that comes into the production and consumption.
•Reuse: processing control. The target is to increase the utilization efficiency of the product and the service.
•Recycle: turn the wastes into source to reduce the handling load at the end of pollution control.
2) Major measurements and methods
•With the utilization of new process and the new technology to simplify, compact, large—size and continue of the production process. Reduce the amount of material and resource of energe to come into the production process and make "Higher Starting Point, Less Investment, Quicker Output and More Profit".
•Optimize the material structure of blast furnace to increase the level of concentrates. Reduce of the source of beginning and clean the process and product.
•Strengthen the cycling reuse of the resource and the secondary resource of the wastes. The importance is to solve the problem of using the industrial wastes with high value and the secondary resource of fine coal ash and the tailings.
•Utilize the no—harm or low—harm new process and the new technology. Eliminate the releasing wastes in the production process. Those wastes are brought out from the steel production and caused the environmental pollution.
•Establish scientific management system and strengthen the management of energy, water, environmental protection and recycling the wastes.
•Make Angang Group as the center to establish the regional ecological industrial garden with the close connection for steel product with the relative circles like chemical petroleum, construction material, and resource etc. and the social life sharing resource, mutual control of the drainage wastes, mutual recycling utilization of secondary resource etc.
3) Target of Development
In 2010, the steel output will be increased from the present 10 million tons to 16 million tons and Angang Group will become a modern plate section concentrate base with international marketing competition ability.
•Increase the iron resource utilization efficiency and reduce and environment loading. The self—production mine consumption will be decreased from 850 kg / t in 2002 to 578 kg / t.
•Reduce the energy consumption. The unit steel comparable consumption will be decreased from 871.8 kgce / t in 2002 to 678.2 kgce / t.
•Utilize the industrial water in an enclosed circuit and make the wastewater "zero drainage".The recycling rate of water will be increased from 91.5 % in 2002 to 94.2%.
•Make the solid wastes as the secondary resource and make it as the new economic increasing point. The comprehensive utilization rate of the solid wastes (not including the tailings) will be increased from 89.1 % in 2002 to 95.9 %.
•Increase the greening-covering rate in the plant site. It will be increased from 32.42% in 2002 to 35%.
By means of developing the recycling economy, we will keep walking the new—type of industrial way raised in the Sixteenth People's Representative Conference ---" high scientific and technical content, good economic profit, low resource of consumption, less environmental pollution and the advantage of talent resource is completely developed". We will make the target of constructing the green ecological Angang Group to promote the harmonic development of our economy, society and environment and make new contribution share for establishing the " well—to—do" society.
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