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  1. Explain what is meant by a 'risk assessment'.
  2. Imagine that you have been asked to conduct a risk assessment of the Sasol/Lurgi gasification process. What information would you need to know in order to do this assessment?
  3. In groups, discuss the importance of each of the following in ensuring the safety of workers in the chemical industry:
    • employing experienced Safety, Health and Environment personnel
    • regular training to identify hazards
    • equipment maintenance and routine checks
  4. What other precautions would you add to this list to make sure that working conditions are safe?

Sasol and the environment

From its humble beginnings in 1950, Sasol has grown to become a major contributor towards the South African economy. Today, the industry produces more than 150 000 barrels of fuels and petrochemicals per day, and meets more than 40% of South Africa's liquid fuel requirements. In total, more than 200 fuel and chemical products are manufactured at Sasolburg and Secunda, and these products are exported to over 70 countries worldwide. This huge success is largely due to Sasol's ability to diversify its product base. The industry has also helped to provide about 170 000 jobs in South Africa, and contributes around R40 billion to the country's Gross Domestic Product (GDP).

However, despite these obvious benefits, there are always environmental costs associated with industry. Apart from the vast quantities of resources that are needed in order for the industry to operate, the production process itself produces waste products and pollutants.

Consumption of resources

Any industry will always use up huge amounts of resources in order to function effectively, and the chemical industry is no exception. In order for an industry to operate, some of the major resources that are needed are energy to drive many of the processes, water , either as a coolant or as part of a process and land for mining or operations.

Refer to the data table below which shows Sasol's water use between 2002 and 2005 ( Sasol Sustainable Development Report 2005 ), and answer the questions that follow.

Water use ( 1000 m 3 ) 2002 2003 2004 2005
River water 113 722 124 179 131 309 124 301
Potable water 15 126 10 552 10 176 10 753
Total 157 617 178 439 173 319 163 203
  1. Explain what is meant by 'potable' water.
  2. Describe the trend in Sasol's water use that you see in the above statistics.
  3. Suggest possible reasons for this trend.
  4. List some of the environmental impacts of using large amounts of river water for industry.
  5. Suggest ways in which these impacts could be reduced

Industry and the environment

Large amounts of gases and pollutants are released during production, and when the fuels themselves are used. Refer to the table below, which shows greenhouse gas and atmospheric pollution data for Sasol between 2002 and 2005, and then answer the questions that follow. ( Source: Sasol Sustainable Development Report 2005 )

Greenhouse gases and air pollutants (kilotonnes) 2002 2003 2004 2005
Carbon dioxide ( C O 2 ) 57 476 62 873 66 838 60 925
Hydrogen sulfide ( H 2 S ) 118 105 102 89
Nitrogen oxides ( N O x ) 168 173 178 166
Sulfur dioxide ( S O 2 ) 283 239 261 222
  1. Draw line graphs to show how the quantity of each pollutant produced has changed between 2002 and 2005.
  2. Describe what you see in the graphs, and suggest a reason for this trend.
  3. Explain what is meant by each of the following terms:
    1. greenhouse gas
    2. global warming
  4. Describe some of the possible effects of global warming.
  5. When sulfur dioxide is present in the atmosphere, it may react with water vapour to produce sulfuric acid . In the same way, nitrogen dioxide and water vapour react to form nitric acid . These reactions in the atmosphere may cause acid rain . Outline some of the possible consequences of acid rain.
  6. Many industries are major contributors towards environmental problems such as global warming, environmental pollution, over-use of resources and acid rain. Industries are in a difficult position: On one hand they must meet the ever increasing demands of society, and on the other, they must achieve this with as little environmental impact as possible. This is a huge challenge.
    • Work in groups of 3-4 to discuss ways in which industries could be encouraged (or in some cases forced) to reduce their environmental impact.
    • Elect a spokesperson for each group, who will present your ideas to the class.
    • Are the ideas suggested by each group practical?
    • How easy or difficult do you think it would be to implement these ideas in South Africa?

Interesting fact

Sasol is very aware of its responsibility towards creating cleaner fuels. From 1st January 2006, the South African government enforced a law to prevent lead from being added to petrol. Sasol has complied with this. One branch of Sasol, Sasol Technology also has a bio-diesel research and development programme focused on developing more environmentally friendly forms of diesel. One way to do this is to use renewable resources such as soybeans to make diesel. Sasol is busy investigating this new technology.

Questions & Answers

what is an isomer?
Kiba Reply
organic compounds with the same molecular formula but different structural formula
liphelo
how is frequency directly proportional to kinetic energy max. and what is the relationship between the wavelength and the energy of a photon. eg if a photon with a greater wavelength and a photon with less frequency. what would be the energies. as in which one would be greater and why
Pearl Reply
relationship wave depend n enrgy greadt reflect of energy n the form of tex shape
thulare
what is Cell capacity?
liphelo Reply
what are hydrocarbons
Nyiko Reply
compounds that are made up of hydrogen and carbon only
Patience
They are compounds that consist only with hydrogen &carbon elements.
Duncan
how do i calculate the work done on an object by a frictional force
Emmelda Reply
@ Emmelda it's W = FxCos180 Where 180° is the angle between Frictional force and where the object is going, it's always 180° because it opposes the motion. Then F is the magnitude of the force and x is the displacement
Vukona
Ohm's law state that provide the temperature remains constant, that potential difference is directly proportional to the current flowing in the circuit
Ezile Reply
state ohms law
Booi
what does ohm's law state ?
Gugu Reply
ohm's law state that the potential difference across a conductor is directly proportional to the current in the conductor at constant temperature
Nqobile
ohm'law in metalic conductor is directly proportional to the potential difference provided the temparature
Nandise
what is the principle on which generator is based
Nqobile Reply
electromagnetic induction
Sethu
Explain it😌
Nelisa
mechanical​ energy is used to rotate turbines inside the generator where a coil placed between two fixed magnets.as the coil rotates it cuts the magnetic flux due to the magnets. the magnetic flux will then induce an electric current into the coil which will be transmitted to the brushes
Ruva
may you Please instruct me on how to do Flemmings Right hand dynamo Rule
Siphe
Fleming's right-hand rule shows the direction of induced current when a conductor attached to a circuit moves in a magnetic field. It can be used to determine the direction of current in a generator's windings
Ruva
 hold out the right hand with the first finger, second finger and thumb at the right angle to each other.forefinger represents the direction of the line of Force, the thuMb points in the direction of Motion or applied force, then seCond finger points in the direction of the induced Current
Ruva
what is spectrum
Mpeh Reply
It is a different combinations of frequency of light or any types of waves.
Duncan
Heii guys what's the topic? Am neww
Vannessa Reply
In nuclear reactions, is it necessary that there must only be one element on the product side and a radioactive particle or you can have a product that are both radioactive particles?
Jobena Reply
conservative force is a force when the work done in moving the object between the two points that does not depend on the path way
Bongiwe Reply
what is conservative force?
Mh Reply
It is a force , that does not have any external features affecting it
Duncan
what does the alternating current do
Kwanga Reply
what is definition of hydrocarbon
jessha Reply
it is the atoms that Contain of C atoms and H atoms only
Xolani
You mean molecules
Jc
yea 💯
Xolani
what's the definition of le chatelier?
Karabo
what is electromagnetic
Daniel
differentiate between DC motor and Ac generator
Kwanga
dc motor converts electrical energy into mechanical energy while ac generator converts mechanical into electical
Ophola
DC has a Split-ring but then Ac has a slip-rings.
Joyous
what's the other name of galvanic cell?
Cwenga
galvanic cell is also called Voltanic cell
Bongiwe
is the chain whereby there is only Hydrogen and Carbon atoms only.
Hlonny
what is the difference between AC and DC moto
Mihle
please check the answer from Ophola and Joyous
Nomsa
AC motor consists of 2 slip rings and a DC motor has a single split ring commutator
Vukona
ac have slip rings n DC has split rings
mudodzwa

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Source:  OpenStax, Siyavula textbooks: grade 12 physical science. OpenStax CNX. Aug 03, 2011 Download for free at http://cnx.org/content/col11244/1.2
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