Energy Efficient Deep Mine Cooling
Keeping mines cool, especially deep mines, is critical for safe and efficient operation.
IDE’s Vacuum Ice Maker (VIM) is the most efficient icemaker on the market and therefore a very efficient method to cool deep mines. With very low power consumption per ton refrigeration it does its job efficiently and effectively.
The VIM produces a concentrated ice water mixture (ice mass fraction at 75% – 80%) that is transportable either pneumatically or by conveyors. This makes it ideal for mine cooling applications where the ice is produced on the ground surface and then transported through a shaft to the different mine levels.
Using transportable ice for mine cooling enables the utilization of the latent heat of the ice, achieving more than four times reduction of the required mass flow of the cooling water that needs to be pumped back to the surface. This results in a significant reduction of energy consumption for the cooling of the mine.
IDE’s VIM can use any type of feed water (fresh or brackish), as the process is performed through direct contact with no heat transfer surfaces.
In addition, by using an optional brine washing system, the VIM can be used simultaneously for desalination of mine water. This reduces the minerals content of the return water.
Benefits of IDE’s Deep Mine Cooling system
- Low energy consumption – less than 1 kW/tonR
- Utilization of the latent heat of ice & reduction of cooling mass flow
- Produces transportable ice
- 5 MW refrigeration per unit
- Usage of any type of feed water
- Optional desalination & Thermal Energy Storage (TES) abilities
- Environmentally friendly
How It Works – Deep Mine Cooling and the VIM
Inside the VIM freezer, water is exposed to deep vacuum. The vacuum forces a small part of the water to evaporate, while the remaining water freezes forming a water-ice mixture.
The mixture is pumped from the freezer to an ice concentrator that separates the water from the ice crystals and delivers the ice to the mine ice distribution system.
In order to maintain the deep vacuum in the freezer, the water vapor is continuously evacuated from the freezer, compressed and fed into a condenser by IDE’s unique centrifugal compressor. Condensing the vapor requires cooling water at 5°C, which is supplied in a closed loop circuit by a standard water chiller.
|Specifications||VIM 400 (Ice)||VIM 850 (Ice)|
|Cooling Capacity||1,750 kW||3,500 kW|
|Ice Making Mass Capacity (1)||560 ton ice/day||1,120 ton ice/day|
|Electrical Supply||400V / 50Hz / 3 Phase or 480V / 60Hz / 3 Phase|
|Typical Power Consumption (2)||235 kW||397 kW|
|Specific Power per tonR||0.47 kW/ tonR||0.4 kW/ tonR|
|Typical Ice Mass Fraction (IMF)||75%|
|Ice Grain Size||0.5-1.0 mm 0.02-0.04 inch|
(1) Considering IMF 75%
(2) The power consumption refers to the VIM unit only and does not include the supporting cooling system (Chiller, Cooling Tower and Cooling Tower circulation pump)