Sept 2014-Sept 2015
Conducted acid wash tests, carbon activity tests, grind analysis tests, chloride titrations, lime strength tests, Sulphur analysis tests, and carbo hardness tests
Assisted with different process optimization projects(chloride level, introduction of new ore)
Metallurgical Accounting and Material Balancing
Other metallurgical duties such as electrowinning cell cleaning, pouring gold, etc.
Member of Energy Steering Committee
Volunteered touring the mill in events such as Mining Matters, Family Day, etc.
My PEY internship took place in Goldcorp RLGM (Red Lake Gold Mines) as a Co-op Metallurgical Student in Metallurgy department. My major responsibilities within the department consisted of field work, laboratory work, and refinery work between the two processing plant: Red Lake Mill and Campbell Mill.
In the field, I monitored reagent use by counting the reagents weekly and sent the information to the warehouse and the purchasing departments for them to order any reagents that are running low, and to our department for cost analysis. I also did stockpile analysis whenever there was ore movement between the three different shafts (Red Lake Complex, Campbell Complex, Balmer Complex), which involved tagging the stockpile samples and sending them to internal assay lab. Moreover, every month, I calibrated mercy scales, which measures percent solids using density, measured dissolved oxygen in leach tanks to assure the presence of oxygen for leaching to take place, and sampled and stored backup tailing samples for both mills. Furthermore, every quarter, I have sent out carbon samples that have been either stripped or acid washed to external assay lab for calcium analysis, and helped with shipping out carbon fines to external company by properly strapping and keeping track of the bags. I have also grabbed and prepared samples for other departments, such as tailing samples for environment department for analyzing different metals to meet with environmental regulations.
RLGM had four laboratories between the two mills for me to do work on. One of my responsibility in the lab included making and mixing of Carmoisine dye, which is the red dye added to cyanide to detect any cyanide leaks. Several different testing was also done to understand the process better. I did carbon activity testing on regenerated carbon and acid wash testing on stripped carbon to monitor our carbon regeneration circuit to see the effectiveness of regeneration and see if any changes are needed to be made. I also did grind analysis on the mill feed and product to calculate operating work index to monitor grind efficiency. In addition, I have titrated different samples taken from the two mills for chloride analysis to prevent corrosion in our tanks. Finally, I have done lime strength test to understand our lime consumption to neutralize our autoclave tailings.
In the refinery, I cleaned gold off of electrowinning cell and emptied plate and frame filter press twice a month. I have also build cathodes for the cell and assisted in pouring of gold bars and shipment.
One of the projects I was involved in was improving the carbon regeneration circuit. Activated carbon is used in the gold extraction process for the adsorption of gold on to the carbon, after or during cyanide leaching of gold. After the adsorption process, gold is stripped out of carbon and sent to the electrowinning cell. After stripping, carbon cannot be used again for adsorption unless it is reactivated. Therefore, carbon is regenerated through acid washing and going through the carbon regeneration kiln. However, too much movement of the carbon through these processes creates carbon fines due to abrasion, which has to be sent out to be burnt to get the gold. To understand this abrasion, I have done carbon hardness test on various different carbons also.
To monitor and examine carbon activity in different regeneration processes, I looked at the effects of kiln temperature, and performed carbon activity tests and acid wash tests. Carbon activity test was done on carbon that has gone through the kiln. The carbon sample from the kiln is tested on a known gold stock solution and is agitated by shaking table. The solution was taken in a time interval to determine rate constant for adsorption process. Acid was test was done on stripped carbon, which involved different acids and concentrations on a shaking table to see which acid is most efficient in removing calcium off of carbon.
Along with these tests, I have researched through books and the internet to find optimal kiln temperature and acid type and concentrations. As a result, kiln temperature was changed to a more optimal temperature, and more acid wash tests need to be done before justifying the change of acid used in the plant. To better perform these tests, size analysis should be done on carbon samples at different points in carbon regeneration process as well as before doing carbon activity test, and better tracking of carbon for matching with kiln temperature shown in process automation and control system. This will allow more control on the size when doing carbon activity test for consistency and the effects of carbon abrasion due to carbon movement through different processes will be seen.
Another project I was involved in was the autoclave tank corrosion prevention. The problem occurred in the middle of my internship when the stainless steel tanks were installed in the autoclave circuit. The tanks started to corrode and needed an urgent attention. This project involved numerous individuals from different departments. My role was to do complete chloride analysis of the two mills to see if there any other tanks with high chlorides and to find the source of chlorides. The source of chloride was found to be coming from underground water and was replaced with another water source for a short term solution. To make the switch, I have helped with drawing of the water process flow diagram to make changes in the simulation software. I have also looked at different long term solution such as different materials for the tanks and new technology to remove chlorides, and their costs and benefits, but more chloride titrations and studies on the tanks must be done before investing in new technology. One of the challenges was testing for chlorides on samples that have cyanide as cyanide react with silver nitrate before chlorides during titration. For recommendation for this task, I would look into reacting cyanide before chloride titration.
The last project I worked on was the Cochenour project. The Cochenour deposit was acquired from Gold Eagle Mines in 2008, located west of Goldcorp’s Red Lake complex and Campbell complex. With the help of Redpath Mining, they have been mining and stockpiling this year and needed to run it through the mill for proper understanding of the Cochenour Ore. I was involved in sampling different parts of the mill every hour and preparing the samples for both internal assay and external assay. As our internal assay was short staffed, I have helped them with sample analysis by doing sulphur analysis on the tailings. I have also cleaned the cell and helped with the pouring of Cochenour gold. This resulted in better understanding of the new ore body and helped the company as a whole.
The various job tasks given to me have contributed to development of my technical skills, general knowledge and professional skills. I gained information on the two different process automation and control system and found out how to look up trends, flow rates, temperature, and other parameters for different equipment in the mill. I could then use this information for projects and could understand the process better. I also gained practice in programming and data analysis in Excel when I was working on metallurgical accounting and analyzing results from the tests I have done. It also helped me with presentation skills when I present the results to others. I learned many different laboratory techniques, refinery work, and different methods of testing through training. Another training I received was Mill Common Core, which covered plethora of topics such as cyanide, silica, sulphur dioxide, conveyor and ladder safety, respirators, WHMIS labels, confined space, Dragger gas detector, fall arrest, fire extinguishers, slinging and rigging, and operating a crane. This really helped me with general knowledge of the safety and work involved in the mill.
As I worked through the year, the safety culture of the mine has been improving continuously. I learned about the safety culture and was impressed by how there was progress every day in safety. I saw myself changing and contributing to the culture by putting on WHIMIS labels on incorrectly labelled chemicals, reading the MSDS, taking care of my PPE (personal protective equipment), and controlling dangerous chemicals. I have also learned a lot about the process of extraction of gold throughout my working year. Before this internship, I had no idea how the gold was extracted from the ore, but now, not only do I know in depth of the process but also the shipment and selling of different forms of gold.
Working at a large company for the first time, I learned about company structure and organizations within the company. I joined a committee myself, Energy Steering Committee, which looks at ways to save energy and costs in the mine through energy saving projects in different departments and going through energy audits throughout the mine site. I learned working with other people, especially with other departments as I have contacted them for help and vice versa. It also improved my decision making skills as I learned what is expected and what is best for the company.
Through this internship, I have learned more about myself, particularly my attitudes and values. I learned that my top five work habits/attributes and traits that employers value are flexibility, physical activity, cautiousness, authenticity, and efficiency. During busy times in our department, I was flexible with my schedule and was able to work overtime as needed. I have volunteered for tours and worked on the weekend, and have worked 84 hours a week when needed. I have helped other departments and colleagues during my normal work hours also. Moreover, I was able to do tasks that required physical activity such as lifting gold bars, cell cleaning, and assisting with gold pours. Following the company’s safety culture, I was very cautious before doing a task, reviewing procedures, assessing hazards, thinking it over, and taking it slow, which has resulted in accident free internship year. I am also authentic with my work and about mistakes I have made. I take responsibility for what I have done and deal with consequences. Finally, I find that I am efficient when doing my work as I am able to multitask and get many tasks done in a limited time.
I have gained some personal and professional insight during my internship and helped me re-evaluate my career plans. In the short term, I plan to graduate from University of Toronto and work after for about one to three years in mining industry. I then plan to go to a grad school in a subject of my interest at that time. In the long term, I hope to achieve both experience and education that allows me to understand myself better, and hope to find a stable career that I enjoy doing.
Overall, I had a really good experience working at Goldcorp. I appreciate all the training and relationships I have had. I learned a lot from my supervisor and enjoyed working with my team. This has allowed me to grow in my current job, lean new skills, and knowledge.