Roasting of copper sulfide ore
Thread Content
I came across a sulfuric acid plant that roasted copper sulfide ore, but the roasting process was almost a failure – the system could not operate properly. We have been entrusted with carrying out the technical upgrades, but I find it extremely difficult. The current situation is as follows: a 30-square-meter calcination furnace, and an acid production system with a capacity of 60,000 tons. The ore contains about 32% sulfur, 5-6% copper, and around 15% water. Pulp feeding, full-acid roasting. While driving, I tried turning on the furnace several times without success. Later, the furnace area was reduced to 25 square meters; the furnace was successfully ignited, but the ore baked did not meet the standards, resulting in a low copper recovery rate. The conversion section is equipped with 4 sets of electric furnaces, with a SO2 concentration of 6%. Please help diagnose what the problem is. Additionally, there is very little information available regarding the roasting of copper sulfide ores (material and heat calculations); could that expert please help address this issue?
How about the roasted ore? Are there any tests available?
I don’t think it’s a big problem; just replace it with a larger fan. I won’t explain the reason; you should understand it.
The problem is likely with the slurry feeder; I think switching to a dry feeder will resolve the issue.
-- I am relatively in favor of switching to dry feeding and using large fans. However, it would be best for the poster to include the relevant analysis and testing data. --
Thank you all! I’ll prepare the materials more thoroughly first, and then I’ll ask everyone to give it another look! Sorry!
I don’t think the feeding method is a problem; slurry feeding is a commonly used method for sulfation roasting.
-- The roasting of copper sulfide is indeed a difficult task. However, there are also many successful experiences in China. --
Characteristics of full-acid roasting of copper sulfide ore: 1. Low roasting temperature: 650±20°C； 2. The baking strength is low, around 4.5 t/m2·d; slight carelessness during operation may lead to the furnace going out of function ； 3. The raw ore has a high moisture content, generally ranging from 12-20% (for flotation) ； 4. The desulfurization rate is low, generally 70-80% ； 5. The SO2 concentration at the furnace outlet is low, around 8%, while it is near 6% at the inlet to the converter.
It’s similar to our system: our copper can be heated to 13%, with slurry feeding, and it’s a 60 M2 furnace; the first operation was successful, and the operation has been stable.
I guess your furnace temperature is high, and the bed efficiency is also high – semi-oxidative roasting?