Metals and Mining

Copper is a valuable metal used in many residential, commercial, and industrial products. From wiring and consumer electronics to HVAC systems to electrical vehicles, copper is an essential element necessary to produce such products. Copper mining is a complex process and water is its’ lifeblood. It allows for the separation and recovery of salable copper. Throughout the milling and flotation cell processed, over double the amount of water is required throughout the crush-grind-flotation-concentrate circuit. Poor control of the mine’s water supply can negatively impact process run-time, leading to constrained production levels and hurting the bottom line.

A large nickel mine in Ontario, Canada produces nickel metal, which is used in the manufacturing of smartphones and rechargeable batteries that power electric cars. Sulfur dioxide (SO2) is a major air pollutant emitted in the roasting, smelting, and converting of sulfide ores. Fortunately, the SO2 is recovered and utilized to make sulfuric acid (H2SO4), an important coproduct that contributes to the mine’s operational revenue. This high-grade sulfuric acid is used to make recyclable fertilizers and paper products.

Coke oven main pressure control is a critical control application for the safe operation of coke making. A plant’s actuator not only must position the cross-over valve to achieve a pressure of 12+/-1 mmWC, but it must avoid pressure spikes from volatile gases soon after coal charging, as shown in Figure 1. If the actuator is slow to respond, the collection main and coke oven gas pressure will increase and leak toxic gas at the oven doors. If the actuator overshoots, the coke oven pressure can decrease to a vacuum, entering oxygen in air which ignites in the over. Both pressure scenarios present major safety concerns.