C14//2 Flashcards
why is smelting bad
uses huge amounts of energy which is very expensive and causes environmental pollution
what other ways are scientists developing to extract copper
using bacteria such as - bioleaching or phytomining to extract copper from low grade ores
why is bioleaching and phytomining better
have less environmental impact than smelting
what is phytomining
grows plants on soil containing low grade copper ore
the plants absorb copper ions
the plants are burnt and the copper is extracted
what is bioleaching
uses bacteria to produce a solution of copper compounds from waste copper ore
scrap iron can then be added to solutions of the copper compounds to displace the copper
how else can copper be extracted from copper compounds
electrolysis
What are life cycle assessments (LCA)
used to assess the impact on the environment caused by manufacturing products
what are the 4 stages of LCA
raw material extraction
manufacture
use/reuse/maintenance
recycle/waste management
how do you carry out an LCA
list all inputs (energy etc) and all outputs (into environment) then evaluate the potential environmental impacts and interpret results
why should LCA be peer reviewed
to check the data and validity of conclusions drawn
why is allocating values to environmental impacts more difficult
requires subjective scientific judgements to be made
what is the aim of reduce, reuse and recycle
to reduce the use of limited resources and energy sources, produce less waste and reduce pollution
what are produced from limited supplies of raw materials
metals, glass, clay
