Western Sintering of Handan Iron and Steel cogeneration technology

Paper Keywords: waste heat recovery; sintering heat generation: environment protection and energy efficiency
Abstract: The dual-pressure sintering Hangang Western double pressure heat recovery boiler and make steam turbine cogeneration technology, this technique does not require power consumption of primary energy, no additional emissions, waste, dust and other harmful gases; and a substantial reduction Central cooler air emissions of heat, reduce heat pollution effect is remarkable, with full use of low-temperature exhaust gas, turning waste into treasure, the multiple meaning of cleaning up the environment.

Preface
In the steel production process, the sintering process of the energy consumption accounts for 10% of total energy consumption, second only to iron-making process, in second place. The total energy consumption in the sintering process, nearly 50% of the heat energy to smoke sintering machine exhaust gas and cooler form of sensible heat into the atmosphere. As the sintering temperature of exhaust gas cooler ring is not high, only 150 ~ 450 ��, with the limitations of previous waste heat recovery technology, waste heat recovery projects often gives a "high cost power generation are low, long life, "the impression has long been overlooked forgotten.

1, Handan Iron & Steel sinter cooler waste heat recovery loop defined classes
Central cooler waste heat recovery, flue gas through the ring of cold gas waste heat recovery boiler heat energy of low taste, combined with low temperature waste heat power generation technology, using waste heat boiler superheated steam to drive turbine parameters do work with low power of the latest complete sets of technology; compared with thermal power, no consumption of primary energy, no additional emissions, waste, dust and other harmful gases; it is the current energy saving and environmental requirements of industrial enterprises under the inevitable trend and the product, with full use of low-temperature emissions, turning waste into treasure, the multiple meaning of cleaning up the environment. Specifically, the significance of waste heat recovery loop cooling is reflected in the following aspects:
1) the use of sintering flue gas waste heat power generation annular cooler, partially replace fossil fuels from the grid power supply for the energy to play the effect of reducing greenhouse gas emissions;
2) reduce the energy consumption of Handan Iron and Steel sintering process, and promote resource conservation, reduce the Hangang energy consumption per unit of output, increasing the efficiency of enterprises;
3) help enterprises to achieve sustainable development goals to reduce the local thermal power plants brought about by the regular S02, NOX, air pollutants like dust and help to improve the local energy structure, improving energy security.

2, Hangang New Area sintering cogeneration technology
Handan Iron and Steel Plant Handan Iron and Steel sintering District 2 production lines, each sintering 360m2 of production line 1 set and 1 set 415m2 sintering machine cooler ring. Each annular cooler configuration 5 the same blower, blower air volume every 45.3 ~ 48. 4X 104Nm3 / h, wind pressure is about 3648 ~-4070Pa, the blower on the annular cooler air through the material layer of mineral aggregate, mineral material is cooled to 150 ~ 200 �� into the next process after; cold and mining heat transfer material into a 450 ~ 150 �� after the hot flue gas, respectively, to the atmosphere, the hot flue gas contains a certain amount of mineral dust also will be released to the air. for the use of sintered steel plant generated by annular cooler exhaust gas sensible heat, Hangang New Area, 2 sets of sintered 68t / h dual-pressure waste heat boiler, and a set of temperature compensation 25MW condensing steam turbine generator steam, the exhaust heat recovery through waste heat boiler superheated steam generated by in the turbine power generation.

2.1 sintering flue gas cooler ring system. Sintered annular cooler air the original 22 interlinked rooms, the sintering process to a waste heat power generation # 5 # Wind Room (corresponding to the 1 # fan) and 6 # ~ 10 # Air chamber (corresponding to # 2 fan) of gas collected, respectively, through the gas system from 1 # and 2 # flue into the waste heat boiler, waste heat boiler as a heat source.

# 1 fan in the range set on the exhaust flue baffle, Tower 1, the impact of settlement type dust collector, blower # 1 # and 2 share a table within the flue gas circulating fan (fluid coupling speed) and alternate row of Block 1 Air chimney, and flue gas waste heat boiler in each system were set up 3 sets of tee damper, heat recovery system to facilitate fault isolation waste heat recovery system at any time, to ensure the normal sintering.

Export air circulating fan (I #, 2 # Central chiller for backup) through the annular cooler is heated to 4000C or so, were introduced through the damper to the waste heat boiler, (when the waste heat boiler failure to switch to the row of baffle damper empty), 1 #, 2 # was heated furnace smoke ventilation before entering the heat baffle-type filter is simple to simple dust (dust 50%). by heat, gas heat furnace was reduced to 1500 C or so. through the filter After removal, the circulation fan through the gate into the ring cooler door again, when the waste heat oven door closed when the gate failure, annular cooler cooling air is still needed from the original 1 # 2. # loop cooling fan entrance.


Circulating fan is required before entry to add 15% of the cold wind to enter, in order to enter the ring cold winds will reach the original value.

2.2 cogeneration sintering process parameters: Handan Iron and Steel 2 sets of sintering New 68t / h dual pressure low temperature waste heat boiler QC400 (400) / 450 <350) -70 <20) -2.35 (0.49) / 425 (230)-type heat boilers, pressure does not help for dual fuel natural circulation boiler, cooler ring for the sintering exhaust gas waste heat recovery and dust removal. reposted elsewhere in the Research Papers Download http://www.hi138.com tower layout of the boiler ( tight seal), when the boiler into the working state, the flow of boiler flue gas at the top level of the entrance corner of the flue, turn the heat flow through the body surface, the heat from the boiler at the bottom of the flue gas after the discharge.

Water system of the boiler heating surface by the preceding tube box, cylinder pressure cooker, pressure drum, temperature control, a steam superheater header formed. Boiler feed water (condensate) into the console by the respective water economizer After heating, close to the saturation temperature of the water into the drum, the drum by the decline in the water pipe into the evaporator, the evaporator heat back after a soft mixture of drum (separator), the drum (separator) within the separator, separating off the water back to the drum of water space, saturated steam through the saturated vapor withdrawal tube is sent to the superheater, saturated steam is heated in the superheater into superheated steam, and then by the desuperheater thermostat , after the required steam temperature, the main steam pipe into the turbine.

3, the sintering environment protection and energy efficiency cogeneration
Sintering cooling fan is currently a total of 10 units, according to previous processes, emissions are not treated directly to the atmosphere. Sintering process of waste heat power generation flue gas emissions from the open to closed, in principle, into the waste heat emissions from furnace dust , launched after the sintering process waste heat power generation, each emission reduction per hour 7. 7t / h, calculated according to 8000 hours of operation, 2 sets of annual emission reduction sintering 123,200 t smoke.

Sintering process in order to reduce cycle cogeneration fan wear, annular cooler exhaust fan cooling air into the circulation prior to the dust, integrated dust removal efficiency of about 80, according to the boiler dust content lOg/m3, the total gas volume 770100m3 / h calculation, 2 waste heat boiler soot (mainly iron ore) to collect the amount of 12. 32t / h. iron ore a year to collect 98,560 tons.

4, Handan Iron and Steel sintering process waste heat power generation soldiers. The following characteristics and advantages
1) The sintering process uses waste heat power generation ring cooler waste flue gas heat recovery power generation, not only do not consume any fossil fuels, and Handan Iron and Steel Group sinter cooler waste heat power generation project ring significantly reduce air emissions annular cooler heat, reduce heat the effect of pollution significant.

2) waste heat boiler exhaust gas cooler ring sent back to recycling, while imports increased boiler flue gas temperature, increased evaporation of the boiler, increasing the turbine's power output: On the other hand prevents the cold gas in the ring mineral dust emissions to the air, play an important role in environmental protection.

3) waste heat recovery system with 100% gas bypass system, if the heat recovery steam generator failure, the control system can quickly start of the original 1 #, 2 # loop cooling fan, and close the chimney flue damper switch, switch to the original running condition, and fully guarantee the safety of sintering the main process and normal operation.

4) The boiler flue gas intake system with dual-channel, high-temperature flue gas heat exchanger heating surface by the part of the high-pressure, low temperature flue gas heat exchanger heating surface by the part of the low-pressure, high temperature and low temperature flue gas flue gas temperature dropped quite, the two shares gas mixture and then with the rest of the heating surface heat transfer, full use of the different quality of flue gas to achieve energy cascade utilization of flue gas to improve the efficiency of energy recovery.

5) The dual pressure heat recovery boiler and steam turbine double pressure compensation. Sintering process using two-pressure waste heat power generation waste heat boiler, heat recovery efficiency programs in a variety of heat recovery is the most efficient, most significantly to the cold gas in the recycling loop heat; dual-pressure steam turbine can make full use of superheated steam generated by waste heat boiler to improve power generation. Links http://www.hi138.com Research Papers Download