NUCOR mini mills are based on extensive use of scrap metal in electric arc furnaces. Cleveland Ciffs just bought a huge stake in AK Steel and plans on using its Minnesota Irom money to create a all American vertical intrigrated operation. I was always assumed that Virgin iron ore was better aka Taconic pellets. But perhaps scrap metal takes less energy to process.I still saw long trains of ore in Duluth-Superior when I was there last year so some mills still use it and I hear that China is buying out our metallurgical coal & scrap metal
I believe there is more demand for steel than just processing scrap can provide.
I understand that there are some grades of steel that require blast furnace produced iron. Taconite pellets from a single source can be fairly uniform and of known composition. Scrap may contain many alloys.
It likely depends on what the metalurgist wants. I don’t pretend to be a metalurgist, but I believe that even using recycled steel allows for making some adjustments in the final product.
Many years ago, I mentioned Nucor Steel to the father of the woman I was dating at the time. He was a structural engineer and only common courtesy kept him from getting profane about the quality of their product.
Some integrated steel producers (primarily Republic Steel) had electric furnaces at their mills which produced steel from carefully selected scrap. It’s not a new procedure.
I was always of pretty much the same opinion, believing that the recycled steel was good mostly for lawn furniture and the sort. But I soon gathered critics who claimed that considerable effort was put into classifying and sorting the scrap, by content.
I still don’t think that I would relish having my motorcycle frame made from someone’s old swingset.
Iron ore can’t be much used in an arc furnace because the furnace depends on the contents to electrically connect the electrodes. Iron ore is not a conductor. Scrap iron and steel are. So is “fresh” iron and steel.
Arc furnaces were first used to make the highest quality steel.
The one that was around here was closed in 1991. I know they produced rebar. I don’t know what else.
Ed
Why not? Some people would make a motorcycle frame from swing set tubing straight away - without recycling/remanufacturing it through a steel mill. There are people that think exhuast tubing is suitable for safety cage construction in race cars. I am not one of those people.
There are a multitude of grades of steel that each have specific uses. Use the wrong grade for the wrong purpose and disaster is not far behind.
I recently was pricing steel for a power hammer build and the costs for new steel are outrageous. But what’s really interesting is that scrap prices haven’t risen along with the cost of new steel. So it does seem that there is a demand for new steel produced from ore and that scrap steel isn’t able to make up the difference in demand.
We move about 15 thousand loads a year for various Nucor mills. Beams, channel steel, and of course coils. Its a very high quality product… which explains why they’re the largest steel producer in the US albeit steel made from recycled scrap. Nucor as a whole is a top notch company in terms of how they operate… how they treat their employees and vendors.
I suspect that it is crucial for a responsible recycler to understand both his sources as well as his customer’s needs.
Many of us likely think of recycled metal as a product of those free lance scrappers who drive their pickups down our alleys a half hour ahead of the garbage trucks, piling high everything from bicycle frames to bed posts.
When in reality many are sourced directly from machine shop mill tailings and such, where the composition is fairly reliable.
Both American Steel Foundries and Bradken (formerly Atchison Castings, Rockwell, and LFM) make all their steel castings for freight car trucks, couplers, draft gear end sills, and locomotive truck frames and all their other products by melting scrap. They are selective what they use and produce high quality alloys of whatever chemistry is required by the customer. A lot of the scrap is railroad wheels.
Dave
Ten or 15 years ago I heard about iron nuggets as an alternative to taconite pellets. They were also processed near the iron mines. They could be used in mini-mills, and seemed to be set to remake the steel industry. However, that doesn’t seemed to have happened. Now when I google “iron nuggets” I find there is a computer game involving iron nuggets, and it’s hard to find links to actual industrial topics.
Add the word ‘processing’ to your ‘iron nugget’ search and all sorts of things appear.
https://www.energy.gov/eere/amo/itmk3-high-quality-iron-nuggets-using-rotary-hearth-furnace
The Mesabi Nuggets plants in Minnesota were shut down during the last Iron Ore price crash. Even though Iron Ore prices have rebounded I haven’t heard that the plants have reopened.
I had the opportunity to watch an electric steel mill in Lemont IL. start a “melt” and it is impressive. Carbon rods that are below a “lid” fed by about 12 large (4" dia.) cables that start dancing like junp ropes as the lid is lowered into the crucibe and contact is made with the scrap metal. and the sound and vibration is fear inspiring.
I spent 3 years working at a cast iron foundry, the primary customers were rail (including ASF).
99% of the raw material was scrap, but EVERY single melt was analyzed via spectrograph as to content and adjusted as needed. I would suspect it is the same for every steel producer as well.
I’m glad you chimed in on this discussion. I’m a lumber guy so I don’t have deep knowledge about steel. Steel production is pretty sophisticated. It seems to me, the steel manufacturers would have the technology to weed out what they don’t want from the scrap steel. When they start with iron ore, don’t they have weed out stuff they don’t want?
No idea on whether mines are open, but the Great Lakes ships are hauling like crazy (also a Boatnerd).
Somebody with more experience can probably correct me, but from what I understand, even with recycled scrap, the process burns out most additives in the scrap metal. They have to then add back elements to get the alloys they desire from the melt. It is then poured and rolled to final stock.
Which is why the disparity between scrap prices and new steel is interesting to me. It implies to me that the bottleneck is in the mills, not in feedstock.