Slag generally refers to coal slag, which is a type of industrial solid wasteResidual slag discharged from coal-fired power plants, industrial and civil boilers and other equipment. is also called slag. Smelting waste slag refers to converter slag, electric furnace slag, ferroalloy slag, alumina red mud and non-ferrous metal ash, but does not include smelting water slag. blast furnace.
Slag is an important phase involved in various metallurgical reactions and has the function of removing impurities from steel and protecting molten steel. They keep the slag in good condition at all stages of electric furnace steelmaking. This is one of the important conditions for producing high quality steel.
Metallurgical waste slagrefer to various solid wastes generated during the production process of the metallurgical industry, mainly referring to blast furnace slag and steel slag generated in ironmaking furnaces; -smelting of ferrous metals, such as copper slag, lead slag, zinc slag, nickel slag, etc. as well as red sludge discharged from bauxite alumina refining and a small amount of iron oxide slag produced during the steel rolling process.
Slag is also called molten slag. It is a molten mass floating on the surface of metal and other liquid substances generated during the pyrometallurgy process. Its composition is composed of oxides (silica, alumina, calcium oxide, magnesium oxide). ) Mainly, it often contains sulfide and a small amount of metal.
1. Full utilization of remaining gas and hpresidual heat
Blast furnace gas, coke oven gas, converter gas, dry quench coke steam, and other low temperature steam Most of the waste heat steam is used for power generation: the company currently has 2 × 3 MW, 1 × 6 MW and 2 × 9.5 MW thermal units, with an annual power generation capacity of approximately 250 million KWH and direct economic benefits of approximately more than 115 million yuan.
2. Comprehensive utilization of wastewater
The company's various existing production recycling waters in ironmaking, sintering, coking, power, smelting, steelmaking units , steel rolling and others. is about 18,150 m3/h, excluding energy consumption and other operating costs, based on 0.1 yuan/ton of water revenue, the annual direct economic benefit is about 15 million yuan .
3.Full utilization of solid waste
(1) All blast furnace slag is exported as a by-product: water quenching slag produced during the blast furnace production process can be used. as raw material for cement production. Our company produces about 500,000 tons of blast furnace slag every year, all of which are exported as by-products to cement manufacturers such as Conch Cement Group, with an annual economic income of about 10 million yuan.
(2) Dust removal ash are all used as raw materials for sinter production: blast furnace gas gravity dust removal, dry dust removal, blast furnace taphouse dust removal, gas ash and iron-containing smoke dust collected daily and coal collected during dedusting of the coking ground station Dust, iron-containing powder dust (smoke)collected by cyclone dust collector at the head of the sintering machine and electrostatic precipitator at the tail of the machine, dust collected when transferring other raw materials, etc., powder dust (smoke) collected every day by the 60 (sets) of dust collectors belonging to the company. There are about 400 tons in total, all of which are used as raw materials for sinter production; of dust containing iron is recycled each year. Based on 300 yuan/ton, it can generate direct economic benefits of 42 million yuan per year.
(3) All steelmaking red mud is used for sintering of raw materials: the dust removal water of the steel converter gas venturi is treated in the inclined plate sedimentation basin then recycled. The red mud at the bottom of the sedimentation basin is entirely transported to thesintering ingredients through the mud. pump and is not discharged outside. The production volume of red mud is about 25,000 tons. Based on 100 yuan/ton, it can generate direct economic benefits of 2.5 million yuan per year.
(4) Coal tar, tar residue, etc. are exported as by-products: approximately 24,000 tons of coal tar and tar residue produced during the coking production process are exported to relevant chemical enterprises and municipal management departments. and other units each year. The annual economic income is about 26 million yuan.
The above “three wastes” comprehensive resource utilization projects generate direct economic benefits of about 210.5 million yuan per year. On September 18, 2006, it passed the certification of ISO14001 environmental management system;
During the period of "onzth Five-Year Plan", Wuhu Xinxing Cast Pipe Co., Ltd. will be built in a "clean" factory environment;
During the "Eleventh Five-Year Plan" period, Wuhu Xinxing Cast Pipe Co., Ltd. will be built in an "industrial tourism zone". The company's total investment in environmental protection between May 2003 and the end of 2009 was approximately more than 360 million yuan, accounting for about 15% of the total investment in technological transformation during of the same period once iron making, coking, sintering, power, pipe casting, pelletizing, steel making, steel rolling and other processing projects. completed, the environmental benefits generated are as follows:
1 Blast furnace gas dries dust removal system3 60 sets (sets) of dust collectors, including a set of desulfurization plants.of coke oven gas, coke oven coal loading and dust removal of coking ground station, environmental dust removal of dry quenching coke and dust removal of blast furnace withdrawal site. A total waste gas treatment capacity of 6.8 million m3/h (an additional waste gas treatment capacity of approximately 6 million m3/h before technical transformation) has been achieved, bringing the rate of 100% waste gas treatment. The main pollutants include smoke. (dust), SO2, NOx, etc. Outgoing to standard.
2. Transform a set of coking phenol cyanide wastewater treatment plants, adding a new wastewater treatment capacity of 35 m3/h, as well as a complete technical transformation of the production water supply system and drainage of the entire plant; was realized ; total industrial water consumptionThe company's water consumption is about 18,500 m3/h, of which the new water consumption is 310 m3/h (390 m3/h less than before the transformation), the repeated water consumption (circulated ) is 18,130 m3/h, and the reuse rate of produced water is 98% (an increase of approximately 20 percentage points compared to before the transformation); production and domestic wastewater from pipe casting, ironmaking, sintering, etc. are collected in a 4,000 m3 pool for treatment by sedimentation then treated in a secondary purification tank. All of this treated wastewater is used as supplemental water for the circulating production water, thereby achieving zero discharge of production wastewater.
3. Noise at the plant boundaries from major noise sources essentially meets standards.
4. Solid waste: All blast furnace slag is exportedtees as a by-product (460,000 tons of blast furnace slag were exported in 2009, about 400 tons of dust ash collected by 60 sets (sets) of); dust collectors are all used daily for sintering. The use of production raw materials reduces smoke dust (powder) emissions by approximately 140,000 tons per year.
5. At the end of 2009, the company's green area was 96,930 m2, with a green coverage rate of 12.27%, the green space per capita is 25.61 m2, further greening, beautifying and purifying the environment.