week 6 + field trip

Question 1

Define mining

Answer 1

Commercial exploitation of mineral or energy resources. the extraction of material from the ground in order to recover one or more component parts of the mined material.

Question 2

what is the difference between mineral processing and metallurgical extraction

Answer 2

processing is physically separating and concentrating ore minerals

metallurgical extraction aims to destroy the crystallographic bonds in the ore in order to recover the sought after element.

Question 3

what forms of mineral processing are there

Answer 3

crushing, grinding, floatation, and gravity, magnetic and electrostatic separation.

Question 4

what is a metal

Answer 4

elements which have characteristic chemical and physical properties like the ability to lose one or more electrons or the ability to conduct heat and electricity

Question 5

what is a metalloid

Answer 5

elements with metallic and non metallic properties such as ability to gain electgrons

Question 6

what is a heavy metal

Answer 6

metals with density greater than 6 g cm-3

Question 7

what is common in metal ores

Answer 7

found in chemical combination with other elements forming metal bearing ore minerals such as oxides or sulfides.

Question 8

what is the difference between ore minerals and industrial minerals

Answer 8

ore = minerals from which elements can be extracted at a reasonable profit

industrial = any rock or mineral of economic value excluding metallic ores, mineral fuels and gemstones. It has an industrial use.

Question 9

what are the valueless minerals associated with an ore

Answer 9

gangue minerals

Question 10

what characterises coal

Answer 10

dual porosity with fractures (cleats) which are larger than micropores. Methane is loosely sorbed on coal and can be released due to its permeability

Question 11

what functions coal permeability

Answer 11

cleat number, connectedness and other minerals filling the voids.

Question 12

what kind of hazards are associated with coal mining and what is involved in most coal mine disasters

Answer 12

rockbursts and methane explosions, suffocation. methane is involved in most of the disasters.

Question 13

how much more potent is methane than CO2

Answer 13

28 times more.

Question 14

what do we want to do with the methane

Answer 14

dont want to release it, its better to burn it. as an energy source it releases half the carbon as coal

Question 15

where are most of the major coal seam gas exploration areas in australia

Answer 15

NSW and QLD

Question 16

what is hydraulic fracturing (or fracking)

Answer 16

where water, sand and other chemicals are injected into a well that leads to the coal seam and creates fissures. natural gas flows out of the well at the top.

Question 17

how much water is recovered in shale fracking

Answer 17

9-40%, always needs water because its dry.

Question 18

what uses more water - shale gas or CSG

Answer 18

shale gas is a consumer of water

Question 19

why do you use a cluster of piezometer

Answer 19

to determine the level of the different aquifers

Question 20

what is flowback water

Answer 20

the withdrawn water following fracking. CSG produces the same or more of the same amount of water as was injected.

Question 21

what is produced water

Answer 21

the residual water after flowback water is removed. the chemistry is natural and reflects the geological origins of the water

Question 22

when is there a peak in stable production of gas

Answer 22

after the dewatering stage

Question 23

what sort of disruption is associated with CSG

Answer 23

drill pads, haul roads, PW storage as well as devege, soil erosion and habitat loss

Question 24

what risks are taken when pumping gas from CSGs

Answer 24

aquifer leakage and contamination of the groundwater by the hydraulic fracturing fluids.

Question 25

what are some of the issues associated with produce water volume

Answer 25

evaporation (leftover brine)
discharge (what happens to small catchments, water tables or to the ocean?)
transporting it away (what happens elsewhere)
reinject brine

Question 26

what level of TDS is suitable for livestock that uses produced water

Answer 26

<1000 mg/kg

Question 27

what is characteristics of produced water

Answer 27

if you discharge sodium rich salts, you are increasing erodibility and erosion. having double charges ions doesn’t satisfies all charge points allowing more to stick to it (like clay).

Question 28

can produced water be beneficial

Answer 28

yes, its different in each state

Queensland: water is used for the environment and users, as well as discharging

NSW: reuse and reinjection, treatment and resuse is approved on case by case

Question 29

what are some treatment methods for re use of produced water

Answer 29

remove particulates, remove salt and disinfection

Question 30

what is the preferred options for use of CSG water

Answer 30

aquifer reinjection, use of untreated water where no impacts would occur and appropriate treatment and reuse for agricultural, industrial and potable purposes.

Question 31

what are non permitted options for use of CSG produced water

Answer 31

disposal via evaporation dams, to surface waters or to land

Question 32

what are the two greatest environmental challenges for CSG water

Answer 32

salt and brine