Environmental Engineering in South African Gold Mines

These flashcards cover heat load calculations, air requirements, and bulk air cooling methods in O.F.S. gold mines as described in environmental engineering lecture materials.

According to Figure 38.5, what do the heat flow rate predictions specifically refer to?

O.F.S. gold mines

In the provided example, what was the heat load predicted for a virgin rock temperature (V.R.T.) of $47,5\,^\circ\text{C}$ and a distance of $2\,500\,\text{m}$?

$176\,\text{kW}$ per $1\,000\,\text{tons}$ per month

What is the determined heat production rate after adding a correction factor of $+12\%$ for a reject temperature of $27\,^\circ\text{C}$ in the example?

$197\,\text{kW}/1\,000\,\text{tons}$ per month

What was the final mine heat load calculation for a production rate of $150$ in the example?

$$197 \times 150 = 29\,550\,\text{kW}$$

What is the formula used to calculate heat added by fissure water ($q$)?

$$q = M \times C_{pw} \times (\text{VRT} - \text{reject temperature})$$

In the fissure water heat calculation, what value is used for the specific heat capacity of water ($C_{pw}$)?

$$4,187\,\text{kJ/kg }^\circ\text{C}$$

What was the total heat load in the example, combining the mine heat load and the fissure water heat load?

$$29\,550 + 1\,288 = 30\,838\,\text{kW}$$

What temperature is associated with the '1st. critical horizon' in Figure 38.4?

$$27\,^\circ\text{C}$$

According to Source 4, what are the two main effects of the fouling of tubes?

It reduces space inside tubes and decreases the ability of heat transfer.

What are the six design considerations listed for Methods of Bulk Air Cooling?

Pumping costs, volume of air to be cooled, positional efficiency, size of excavation, and optimization of total owning costs.

What are the two types of coolers for Bulk Air Cooling mentioned in the notes?

Cascade Cooler and Horizontal Spray Chambers (2 stage cooling)

For what specific application is a Cascade Cooler used?

Used in cooling cars.

What is the title of Figure 38.4 in 'Environmental Engineering in S.A. Mines'?

Air requirements for Zone 1 in the O.F.S.