VCE Environmental Science » fluoride

Report on your findings from Portland Aluminium

brittgow — Mon, 10 Aug 2009 23:32:56 +0000

Water discharge from Portland Aluminium

By now you should have all your information, including relevant data, about fluoride as a pollutant at Portland Aluminium. Your report should include the characteristics of fluoride, including strategies that reduce the risk of pollutants affecting human health and the environment as well as the direct and indirect effects on the health of humans and the environment.

“On completion of this unit the student should be able to describe the characteristics of pollutants and evaluate the management options for reducing the risk of a pollutant affecting the health of the environment and humans.”

It is important that you make an attempt to evaluate the management options that Portland Aluminium have implemented to reduce fluoride emissions at the smelter. Have they been successful? Could they be improved? Compare emissions from Portland to other aluminium smelters – how do they measure up?

Portland Aluminium tour

brittgow — Fri, 07 Aug 2009 03:26:28 +0000

The Portland Aluminium smelter is situated on 600 hectares of land, 500 of which form “Smelter in the Park”, a once-barren area that has been revegetated with a large variety of indigenous plants. This area forms a buffer zone, that protects surrounding residents from the full impact of gaseous emissions from the smelter. There are five monitoring stations at different locations around the smelter that provide data on fluoride and sulfur emissions on a regular basis. Portland Aluminium also routinely test their workers, using urine and blood tests, as well as exposure badges, which monitor the levels of fluoride that staff have been subjected to.

Environmental scientists also do water testing and take tail-bone samples of the local kangaroos and teeth, bone and horn samples of the beef cattle , to test for long-term fluoride exposure. An international botanist expert visits annually to check for signs that toxic emissions may be affecting local vegetation. Signs of fluoride exposure include yellowing and curling of leaves and tissue death.

Portland Aluminium use several methods to prevent excessive fluoride emissions, including the A398 fluoride recovery system, in which fluoride emissions are captured from the hooded aluminium pots and forced through a conveyor of alumina, to form reacted or fluoride-enriched alumina. This is then added to the pots, which reduces the temperature (and therefor the energy required) to obtain the pure aluminium. The particulate and gaseous emissions are filtered through huge canvas bags, also coated with alumina, which traps 98% of fluoride.

In the potrooms, the major point source of fluoride emissions, Portland Aluminium have laser air monitoring of gaseous fluoride, with a traffic light system – green, amber and red. Between 045ppb and 600ppb, the lights are green; between 600ppb and 800ppb the lights are amber and above 800ppb the lights are red, which indicates an error in the process – too many hoods open at the same time.

The Victorian governmetn has produced this site, “Fluoride in the air environment“, which describes the sources of fluoride in Victoria and how it is monitored, including EPA limits.

Week 1, Term 3 – Unit 4

brittgow — Wed, 24 Jun 2009 01:06:17 +0000

Photo Source - Most of the anti-fluoride protest is scare-mongering and irrational – note the swastika!

As I will be with the Year 9/10 camp, at Rubicon during the first week back at school, you will need to work through Chapters 1 and 2 in class. The Area of study is pollutants, with case studies of mercury, sulphur and fluoride. In the previous post there are some worksheets for you to download and complete.

You may have heard about fluoride in the news recently – there have been bomb threats to Barwon South West Water and a Victorian MP is under police guard after fluoride has been intoruduced to Geelong’s water supply. Warrnambool received fluoride in the water supply last year after many months of contentious debate. Some people claim it is poison, while many scientists and dentists believe it reduces the incidence of tooth decay. Should we consider it as a pollutant?

Unit 4: Pollution

brittgow — Tue, 16 Jun 2009 03:45:52 +0000

Photo Source

Over the two week study break and before you return to school on Monday 13th July, you need to have read Chapters 1 and 2 from the “Issues of Sustainability” textbook. This is an introduction to human health and the environmental effects of pollution in the air, water and soil. Try this worksheet to match various terms with their definitions: environmental-pollutants-worksheet.

Use the following to write notes about mercury, sulphur dioxide and fluoride: unit-4-pollutants-table

Fluoride emissions at Portland Aluminium

brittgow — Mon, 21 Jul 2008 00:32:12 +0000

Photo Source

Following our excursion to Portland Aluminium on Wednesday 6th August you will be required to complete a report considering the fluoride emissions of aluminium production. Make sure your report includes the following information:

Have you identified where fluoride comes from and whether it is a point source or diffuse source?
Is it a solid, liquid or gas pollutant?
How is it transported through the environment?
Does it bio-accumulate?
What are the direct and indirect human health effects?
What are the direct and indirect environmental effects?
How have Portland Alcoa Aluminium reduced fluoride emissions and by what percentage?
How does Portland Alcoa Aluminium monitor emissions and who do they report to?
What requirements does this organisation impose upon PAA and what are the penalties for non-compliance?
Using your knowledge of the characteristics of pollutants suggest ways in which the PAA could improve their environmental management to reduce risks associated with pollutants.
Assess the credibility of primary data collected; compare data collected relating to the pollutant with relevant standards or protocols.

Fluoride emissions from Portland Aluminium

brittgow — Fri, 18 Jul 2008 04:34:53 +0000

Photo Source

The first outcome for this term is as follows:
“Describe the characteristics of pollutants, and evaluate management options for reducing the risk of a pollutant affecting the health of the environment and humans.”
You are required to write a report describing the properties and effects of fluoride. This task is worth 25% of your school-assessed course-work. We will be visiting Portland Aluminium on Wednesday 6th August (departing 9.00am and returning 3.30pm) to meet the environmental officer and obtain primary data regarding fluoride emissions from point, diffuse and fugitive sources.

You can access the unit-4-assessment-task-fluoride sheet here.

You can use the following resources:

Victorian Government – Fluoride in the air environment

National Pollutants Inventory – Fluoride compounds

Alcoa in Australia – Environmental Sustainability

Australian Aluminium Council – 2007 Sustainability report

Spent Pot Lining Treatment and Fluoride Recycling Project

Environmental Improvement Plan for Portland Aluminium (2003/4)

Fluoride a pollutant?

brittgow — Tue, 08 Jul 2008 01:49:41 +0000

Photo Source

Your parents have probably told you hundreds of times to brush your teeth – and a fluoride toothpaste is recommended by good dentists everywhere. Many cities worldwide have fluoride added to their water supplies – Beaconsfield in Tasmania was the first town in Australia for this to happen and currently the Warrnambool City Council and residents are debating the issue. Low concentrations are good for teeth, but excessive concentrations can lead to debilitating disease, such as skeletal fluorosis, which has devastated some communities. Millions of people are exposed to excessive amounts of fluoride through drinking water contaminated from natural geological sources. As a result, many suffer conditions ranging from mild dental fluorosis to crippling skeletal fluorosis. Clinical dental fluorosis is characterized by staining and pitting of the teeth. In more severe cases, all the enamel may be damaged. In skeletal fluorosis, fluoride accumulates in the bone progressively over many years, leading to stiffness and pain in the joints. In severe cases, it can cause changes to bone structure, calcification of ligaments, and crippling effects.

One of the major anthropogenic sources of floride compounds is the aluminium industry. Scientists from the CSIRO and Portland Alcoa have developed a process that renders the flouride less harmful by converting the spent pot linings to a less harmful “synthetic sand”.