Acid Rock Drainage (ARD) with Automated Neutralization Potential
Acid Rock Drainage (ARD)
Waste from mining activity that contains sulfide minerals has the potential to form a source of acidic contamination in the environment called acid rock drainage (ARD). Therefore, testing waste materials helps provide data for the mining industry to create more informed and effective waste management practices.
Testing ARD
There are two types of methods to predict ARD, Static ARD Testing and Kinetic ARD Testing.
Static ARD tests determine the acid generation and the neutralization potential of a sample. Kinetic ARD tests simulate the conditions for which acid generation happens over time. These tests can occur over multiple weeks to years.
The Static ARD test typically requires a lot of analyst involvement over more than 24 hours. Sample pH must be measured and adjusted every few hours according to the standard procedure with intermittent shaking throughout the test. To mitigate testing of hundreds of samples, MANTECH offers a solution for automating neutralization potential included in the static ARD test, Modified Acid Base Accounting. Automation from MANTECH frees up analysts’ time from these time-consuming, labor-intensive steps by automating the full Static ARD test from start to finish.
Automating Neutralization Potential with MANTECH
MANTECH’s MT30 system measures pH with a pH electrode and automates the addition of HCl and NaOH using 100,000-step burets. MANTECH Pro software records the starting pH value, final adjusted pH value, and volume of acid added. The software also controls each shaker so that the speed, duration and the time they turn on and off follows the standard procedure. The user can select the interval for the MT30 system re-checking each sample and re-adjusting pH as necessary. After 24 hours of shaking the acidified samples, the system will titrate NaOH into the samples until a pH of 8.3 is reached. Stabilization criteria ensure this value is sustained for at least 30 seconds before proceeding. Neutralization Potential is then automatically calculated in the software and listed on the final report along with any of the mid-analysis parameters desired for reporting.
Key Features of MANTECH’s Automated MT30 Neutralization Potential System:
- Shaker Racks with RPM controlled by software
- Custom rack options for user-specified vessels, mountable on shakers
- pH Electrode with automated stirring during analysis and acid addition
- 100,000 Step Burets for acid and base addition
- MANTECH Pro Software
Interested in Automated ARD Testing?
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