Mining Contract: Collaborative Safe Integrated Engineering in Mining (COSINE in Mining)

Contract # 200-2019-06090
Start Date 9/9/2019
Research Concept

This capacity-building contract will support a total of eight PhD students while cross-training them in various disciplines related to mining. Students researchers and advising faculty will conduct research in the areas of mining planning and design that address significant mining health and safety issues.

Contract Status & Impact

This contract is ongoing. For more information on this contract, send a request to mining@cdc.gov.

Underground mines are designed and planned based on various factors including: geology, deposit type, geotechnical characteristics, economic factors, physical limitations, operational parameters, and safety. Decisions include how the deposit will be: (i) accessed, e.g., vertical shaft or decline, (ii) mined, e.g., stope and/or cut-and-fill, (iii) transported, e.g., trucks, rail, conveyor, and/or hoist, and (iv) remediated, e.g., paste or rock backfill. In 2015, there were 136 active metal and nonmetal (e.g., potash, limestone and crushed rock) underground mines operating in the U.S., compared to 1,103 surface mines. There are an additional 405 underground and 1,055 surface coal mines. These operations vary in size and annual production, each with some unique—but many shared—challenges related to ensuring the safety and health of miners.

The research on underground mine planning will occur in three phases:

Underground production scheduling with ventilation

The researchers will intertwine state-of-the-art production scheduling algorithms that produce exact solutions in a timely manner with detailed computational fluid dynamics simulation models that yield accurate measurements of heat and other nuisances such that decisions regarding production schedule and ventilation are made in concert.

For a fixed design, underground mine planning is currently an iterative process involving (i) the determination of a production schedule, or start dates for the activities in question in the absence of ventilation considerations and then (ii) the analysis of the schedule in ventilation software to determine whether or not the scheduled activities produce heat and other nuisances that the ventilation system cannot sufficiently flush out or dilute below regulatory limits. As the depth of an underground mine increases, heat from the geothermal gradient, auto-compression, and equipment can increase significantly. Correspondingly, miners can suffer from heat exhaustion, resulting in numerous physical conditions. This research will produce a methodology such that when excessive emissions are identified in the strategic schedule, engineers have the opportunity to modify the production schedule and/or the ventilation systems to maintain heat levels below acceptable limits.

Integrated mine design and production scheduling

Mine design decisions are often made far in advance of operational decisions, and with productivity as a primary consideration. However, after a mining method is chosen and a corresponding design is tailored to suit production needs, it is imperative to ensure that adequate ventilation is placed underground to mitigate the effects of nuisances such as excessive heat. Ventilation decisions are inextricably intertwined with the timing of activities in a production schedule, yet this timing is often not determined, even on an approximate basis, in concert with the mine design. Therefore, an iterative process is required after the mine design has been established to ensure that the level of ventilation is commensurate with what is required to keep operators safe. An approach that would consider strategic and operational decisions in tandem would reduce costs, enhance productivity, and eliminate the ad hoc nature currently associated with ensuring a safe working environment. This research will develop a mathematical model that would simultaneously consider design and operational decisions such that desired production levels are met while ensuring that design does not need to be altered ex post and at great expense (perhaps even after levels have been dangerously high) to accommodate health and safety requirements associated with heat emissions from the diesel equipment.

Operation-level scheduling with ventilation

We propose a framework wherein short-term schedules are created using a 12 to 18 month time horizon as a foundation, while simultaneously accounting for current operational conditions using real-time monitoring data. Expanding on the techniques identified in Phase I, we propose to integrate ventilation requirements and real-time monitoring data into the short-term underground mine planning process by expanding upon the work of Chowdu (2019). The model provides an operational-level production schedule at hourly or shift-based fidelity that incorporates ventilation capacities and requirements associated with maintaining heat, diesel particulate matter, dust, and/or gas levels below regulatory limits.

Understanding the hazardous conditions that can occur in an underground mine, the development of a short-term production scheduling tool that utilizes real-time monitoring data for, e.g., DPM, dust, and heat, would provide mine engineers with the ability to rapidly adjust the operational schedule in response to changing operational conditions, while meeting the target forecasts and improving resource utilization. Technological advances in the monitoring of diesel particulates, dust, and heat levels in underground mines are now providing real-time data representing the immediate condition of the mine environment. Researchers will use this data, in real-time or near real-time, to provide engineers with a tool that is flexible enough to rapidly respond to changing conditions, thereby reducing the impact of health- and safety-related hazards and operational inefficiencies.

Page last reviewed: 9/18/2020 Page last updated: 9/18/2020