During the smelting of aluminum, there are several needs to enhance the performance by blowing oxygen to prevent oxidization with effective tools. In the meantime, there is a requirement to check the temperature of melted aluminum in order to control the flow of the metal effectively. Eventually, the production process also requires tools with good performance to clean up spilled aluminum metal on the furnace walls and floor. It is optimal that aluminum producers can understand well what kind of Daiwa lance pipe can be used for each of their production steps to reduce cost and increase efficiency.
In this blog, we will briefly explain the manufacturing process of aluminum refining and also introduce our lance pipes suitable for each step of production.
Main Process of Aluminum Production
There are numerous processes in the Aluminum production process, and we summarize the main major processes following:
- Step 1: Aluminum Refining
To make one tonne of alumina, two to three tonnes of bauxite are needed. During the digestion process, boiling caustic soda is applied to the bauxite to dissolve the minerals that contain aluminum. Through sedimentation, clarification separates the bauxite solids from the pregnant liquid. Crystallization in the precipitation stage removes alumina crystals from the liquid. Calcination is a roasting technique to get rid of any leftover water.
- Step 2: Aluminum Smelting
The Hall-Héroult technique is used to melt alumina into aluminum. One tonne of aluminum requires two tonnes of alumina to be produced. Alumina is put into specialized reduction cells known as pots with an electrolytic bath of molten salt known as cryolite at temperatures of around 960°C. The mixture is then injected with an electrical current of 400 KA or greater. Liquid aluminum collects in the bottom of the reduction cell as a result of this current rupturing the connection between the aluminum and oxygen atoms in alumina.
- Step 3: Casting
After that, aluminum is sent to the casting facility, where it is used to create goods in a variety of ways. Many products have alloys added before the solidification step in accordance with customer specifications. In re-melt casting, liquid aluminum is injected into molds at a temperature of more than 700°C. Before the metal is packaged and sent to the client, the molds are cooled and solidified.
Cast aluminum slabs are heated and fed through a series of rollers in sheet ingot casting until the desired plate thickness is achieved or the metal is thin enough for cold rolling, or the slabs are cut into plates. In billet casting, hot cast aluminum billets are either forged into various products, including wheels and automobile components or extruded through a steel die to produce profiles.
Blowing Oxygen to Aluminum Smelter
In aluminum smelters, the challenge is to find tools that are good enough to prevent oxidation. Since blowing oxygen into the melting furnace, it is easy to have corrosion and reduce the life of steel tubes. Having long-lasting life would be helpful and reduce costs by less quantity.
Photo of Worker injecting oxygen into the Aluminum Smelter
Daiwa Calorized Lance pipe (CA) is not only used for oxygen and carbon injection for steel making process mainly with electric arc furnace but also, we recommend this pipe to use in Aluminum Smelter for blowing oxygen, due to the remarkable quality that can prevent corrosion.
Photo of Daiwa CA Lance pipe
Heat Resistance to Protect Thermocouple
During smelting Aluminum into liquid, the temperature will be around 960°C, keeping a stable temperature is a requirement and so CA Lance can be used in this step to protect the Thermocouple and then put into the Smelter for measurement. CA Lance pipe is produced with a one-side welded closed end to protect Thermocouple.
Structure of Calorized Lance pipe:
*1 Refractory Coating: Daiwa CA Lance also has a thin refractory on the interior surface that shields the steel from direct contact with the oxygen stream. On the exterior surface, it has a thick refractory coating that effectively protects the steel from heat attack.
*2 Calorized Layer: Daiwa Lance has a homogeneous calorized layer both inside and out.
*3 Microview of Calorized Layer: Calorizing process - Aluminum diffuses into mild steel when heated up to 1,000°C and forms heat-resistant aluminum-iron alloy (calorized layer) over the surface of mild steel.
Photo of one-side welded closed-end CA Lance pipe
Cleaning Aluminum Plant
Daiwa Thermic Lance (TH) is a steel pipe filled with wires or a mixture of wires and an inner pipe, when burning generates a powerful flame up to 4,000°C without noise and vibration to break up materials quickly. This product is mainly used for burning and cutting large iron castings, stainless steels, brass, non-ferrous metal, refractory materials, concrete, ceramic, natural stone, etc... with high efficiency and productivity.
Conclusion
To cut costs and boost productivity, it is ideal for aluminum producers to know exactly what sort of lance pipe may be used at each stage of production.
If you wish to know more about our Calorized Lance and Thermic Lance to have a try to boost your production performance, let us support you on this journey by contacting our dynamic team.
