Attention, recycling copper industry waste gas treatment integrated solution
Release time:2021-04-23Click:1029
Scrap copper resource scrap copper is the raw material of recycled copper, which comes from social production, circulation, consumption and other fields. The production site of scrap copper resource the production site of scrap copper is changing with the development of society. In the 1950s of the last century, copper scrap resources were mainly produced among the people. In the 1960s, due to the shortage of copper resources in the country, there were almost no copper products in civilian products. Therefore, almost no copper scrap resources were produced among the people. From then until the 1980s, copper scrap mainly comes from industrial and mining enterprises. At present, domestic copper scrap mainly comes from the following aspects.
(1) waste produced by Non-ferrous metal processing enterprises: Copper waste produced by Non-ferrous metal processing enterprises includes pure copper waste and copper alloy waste, such as cutting head and tail, pouring risers, scrap materials, waste secondary materials, copper-containing ash and slag, etc. . The copper scrap produced by Non-ferrous metal processing enterprises was the material allocated by the state in the period of the planned economy. After the market economy, the copper scrap was usually recycled by the enterprises themselves and rejoined in the production process, some of it goes into society, mainly low grade waste and Non-ferrous metal ash.
(2) waste copper resources produced in the field of consumption: the amount of waste copper produced in this field is huge, and it is the main resource of the regenerated copper industry, which is produced in various industrial fields and industrial and mining enterprises in the construction of the national economy. The waste copper produced in this field mainly includes processing waste materials, scrap, waste secondary materials (scrap) , waste machine parts, waste electrical facilities and so on. With the development of processing and manufacturing technology and the acceleration of industrialization, the amount of processing Non-ferrous metal in the waste produced in the consumption field is decreasing year by year, the number and variety of waste equipment, instruments, waste electronic components and waste electrical facilities containing Non-ferrous metal are increasing year by year, and will be the main resource of waste Non-ferrous metal in the future.
(3) waste Non-ferrous metal produced by the society: With the improvement of people's consumption level, the quantity of waste copper produced by the society is increasing, such as waste electric wires, waste household appliances, etc. .
(4) imported waste Non-ferrous metal: As China is a big copper consuming country, the copper resources are seriously insufficient, and the domestic waste copper resources are limited, so China imports a lot of waste copper every year to make up for the shortage of resources. The import of copper scrap can be divided into two parts. One part is pure copper scrap or copper alloy, which is referred to by the customs as six types of scrap. The other part is called waste electrical machinery, electrical wiring and scrap metal, which are mainly used to recover copper. According to customs statistics, in 2003 the country imported more than 3.06 million tons of copper-containing waste, containing about 600-700,000 tons of copper.
(5) defence and military waste: This waste consists mainly of cartridge cases, waste communications and electronic equipment, waste electrical and electronic equipment and waste Non-ferrous metal parts from decommissioned vehicles, aircraft, ships and other military installations.
(1) the temperature of exhaust gas is lower and the air volume is smaller in this stage because a large amount of cold material has to absorb a large amount of heat to melt the raw material.
(2) blowing oxygen harrow slag, because the raw materials are melted and the corresponding additives are added to make slag, and the gaseous harmful metals and additive oxides need to be removed, therefore, the temperature of flue gas is higher and the air volume is larger in this stage than in the stage of stoking.
(3) deoxidization and reduction of copper oxide in copper liquid, due to the need to add natural gas, coal, or trees, during this process, natural gas, coal, or trees that are fed into the copper solution will burn violently and a lot of free carbon will escape to form carbon monoxide as the reduction proceeds, some of the Carbon Monoxide combines with water vapor to produce a certain amount of hydrogen gas (which comes from the combustion of oxygen and natural gas) . Since these gases are flammable and explosive, therefore, the gas temperature in this stage is extremely high air flow is the largest in the smelting process.
(4) thermal insulation casting, since the casting will last for a long time, it is necessary to cover the surface of the liquid copper with a large amount of charcoal for thermal insulation and to stop the combustion system before the start of the casting, at this stage, only when charcoal is added, the flue gas is produced and the flue gas temperature is low and the air volume is small. Solution 1. Dust removal stage, from the flue gas overview, oven feeding stage, blowing oxygen rake slag stage, deoxidization reduction stage and thermal insulation casting stage to solve the improvement.
2.Denitration process
SCR DENOX: SCR means selective catalytic reduction. The core technology of SCR is to catalyze the reduction of NOx in flue gas by ammonia. The principle of SCR is the selective reduction of Nox to N2 and water by NH3 urea or other reductant under the action of specific catalyst, its high removal rate is considered to be the best flue gas denitrification technology, but the disadvantages are larger investment and operating costs. SNCR DENITRATION: Selective non-catalytic reduction (SNCR) for NOx removal is the rapid thermal decomposition of nh_3 and other by-products from nh_x-based reductants (such as ammonia and urea) into nh_3 and other by-products by injecting them into the furnace temperature range from 850 °C to 1250 °C, then NH3 reacts with Nox in flue gas by SNCR to form N2.
Source: Non-ferrous metal