Not so fantastic plastic

You may have noticed that the Carrefour supermarket chain is trying to get people to stop using plastic bags. If you want to understand the damage they do to the environment, then take a look at these two videos about the devastating effect plastic is having on the Pacific Ocean.





You may remember the poet Levi Tafari came to school last year. Here is his tongue in cheek look at the way we use plastic.

World Environment Day

It was World Environment Day on June 5th and I came across two neat videos to mark the event. Take a look at them both and spend a few minutes reflecting on the message:

Talent Show

As you know the auditions for the talent show will be held soon, so get practising and make sure you produce a top-quality act. If you want some inspiration, take a look at this video of 47-year-old Susan Boyle who became one of the biggest hits of the year on You Tube when she appeared on the UK TV show Britain's got talent.

And here is another video that you saw during the anti-bullying sessions we watched earlier in the year:

Ecology Group visit

Last month the Ecology Group went to the recycling plant at Pinto. Here is Miranda Imperial's excellent and highly informative account of the visit.

ECOLOGY GROUP TRIP TO PLANTA DE BIOMETANIZACIÓN Y COMPOSTAJE DE PINTO

A report by Miranda Imperial, 7Z

On Wednesday the 1st of April, the Y and Z families Ecology Group went to the Planta de Biometanización y Compostaje, in Pinto. Firstly, we were taken to the classroom, where two educators explained what they do there with recyclable garbage, methane and organic compost. We were together with Bachillerato children from another school and the level of explanations was a little high for us. As a result, I did not quite understand all they said. Fortunately, the Plant has an excellent website (http://www.rcir.es/6_pintoBIO/6_1_PintoBIO_portada.html), where I could go back for the information I needed for this report.

Urban solid waste disposal is a big problem, especially because there is so much of it. Traditionally, cities have designated landfill sites where urban waste is dumped. These sites are problematic, because the organic contaminants can be leached out into the soil and will pollute our waterways. In addition, natural fermentation of the organic fraction will result in the formation of methane (natural gas) that is released to the atmosphere. Methane is an important greenhouse gas: it contributes to global climate change and remains in the atmosphere for over 10 years. Many of these problems can be solved by constructing a biomethane and composting plant at the dump site. In such plants, the fermentable organic waste fraction is fed to an anaerobic biodigester, where bacteria eat up the organic matter and produce methane that is collected and used as energy source. The leftover is a compost that has organic matter that is difficult to degrade, but that can help aerate soils and is enriched in salts and minerals that can be used directly as fertilizer for plant growth.
Before entering the bioreactor, urban waste must be separated in different fractions. Part of the waste can be recycled and reused. Some other fractions are not organic and can go directly into the dump site. Finally, the organic fraction must be mechanically milled and sieved before entering the bioreactor.

Since 2003, the Biomethanization and Composting Plant in Pinto processes garbage from urban containers of about 1,500,000 inhabitants of the South of Madrid region. Garbage is classified, and metal, plastics, cardboard and paper are recycled. Methane from bioreactors fed with organic garbage and methane recovered from the dump site is used to make electricity, and the residue from the bioreactors is used as compost for plant fertilization. The second component of the site is a sealed dump, where non-recyclable, non-fermentable garbage is stored. However, it is not simply “dumped”. Garbage is deposited in layers, on top of impermeable layers of plastic, loam and gravel, to ensure that nothing leaches down, and with a collection system to recover effluents, both liquid and gas (methane), which are constantly monitored.

This is how the plant works. Trucks bring in the urban garbage and put it in deposits. From them, garbage goes onto conveyor belts for classification and separation. Some of these processes are automated, whereas other separations are carried out manually. After sieving in rotary sieves, coarse and fine fractions are obtained. From the coarse fraction, large pieces of cardboard, plastic of different classes, and metal (with the help of electromagnets) are separated and made into packages that are given to recyclers. Other large pieces, which are considered not recyclable, go into the dump.
The fine fraction is mostly organic, and is conducted to the pulper, where it is mixed with water and made into a pulp. The pulper disaggregates the garbage and prepares it to feed the bioreactor for biomethane production. At this stage, the fine non-organic fraction (rocks, glass, metal, …), that can be as much as 50%, is deposited at the bottom, separated and taken to the dump. After a final filtration, the pulp is taken to a tank for further homogenization and then to the bioreactor, where bacteria will digest it. After bacteria use up all the oxygen, the anaerobic fermentation process that produces methane starts and continues for 3 weeks. Methane is collected at the top and piped to a gas deposit (gasometer), and the solids resulting from the digestion are collected at the bottom.
Methane is burned to generate electricity at the eleven motogenerators that the Plant has, and this electricity is fed to the general electric system.
The solids resulting from digestion contain 90% water. After centrifugation to eliminate most of the water, the residue is moved to a maturation tunnel, where it is mixed with plant residues and incubated under controlled temperature and humidity conditions for up to two weeks, after which the compost is collected and trucked away.

All water used in the Plant, either collected from the sealed dump or from the bioreactors, is treated and reused in the plant or used for irrigation.

Each person living in a city generates about 1.5 kg garbage each day, and this goes into the urban garbage system: it must be collected, transported and treated. Any individual effort on our part to reduce this amount helps lower the difficulties (and cost) of collecting, transporting, and treating it at Plants such as the one in Pinto. Furthermore, some of the most complicated (and costly) processes in treating urban solid garbage come from separating organic matter and reusable materials (cardboard and paper, plastics and metals, glass) from the rest. If we try hard to do this separation at home, treatment at the Plant will be not only easier, but far more effective, and as a result, our garbage will have a lesser impact on our environment.

Energy Revolution

Check out these two videos to see what we can do to help bring about an energy revolution that will help reduce the dangers of climate change.

Earth Day

April 22 was Earth Day. Environmental group Greenpeace are trying to spur people into action in order to take measures to prevent the further destruction of the planet on which we live. Take a look at their latest video and have a think about what you can do to save energy, recycle and care for the environment in which you live.

Respect

One of the most important aspects of life at school is showing repect to your fellow students, teachers and everyone who works with us. Here is an entertaining video produced by the English Football Association that demonstrates what happens when that respect is missing.