Tuesday, January 3, 2012

Students pin hopes on a concrete breakthrough with algae

Today, Wednesday, December 28, 2011, Page 4, Hot News
From http://imcmsimages.mediacorp.sg/CMSFileserver/documents/006/PDF/20111228/2812HNP004.pdf
Source Website: http://www.todayonline.com/Singapore/EDC111228-0000036/Students-pin-hopes-on-a-concrete-breakthrough-with-algae
By Esther Ng, estherng@mediacorp.com.sg, 04:45 AM Dec 28, 2011

PHOTO: (From left) Singapore Polytechnic students Irmahyunita Misnadi, Nur Fathin, Athirah Rusli and Michelle Chan examining a slab of concrete made with algae (inset) and cement.
SINGAPORE - Concrete road kerbs and drains could be made with algae instead of sand, if a group of Singapore Polytechnic students' final year project becomes commercially viable.

The School of Architecture and the Built Environment students found that a mix of algae and cement is strong enough for non-load bearing structures such as precast concrete drain sections, wheel stoppers in car parks and wall partitions.

And the students' finding might potentially be the construction industry's silver bullet, given recent bans on sand exports by neighbouring countries and the emphasis on sustainable construction methods.

PHOTO: Athira Rusli holding some dried algae in her hand. Next to her is a cube of concrete made from algae and cement
Compared to sand, algae is freely available from water catchment areas here and is more environmentally-friendly. "The alkaline chemical in cement affects the skin and breathing in too much of cement particles makes your lung harden. Wet algae reduces these harmful effects," said team member Athirah Rusli, 19.

She added: "Rather than incinerate the algae collected from cleaning up water catchment areas, algae's binding strength can be put to construction use."

Experimenting with various proportions of algae and cement, students found a mix containing 40 per cent algae and 60 per cent cement to be the strongest.

PHOTO: Sea of algae. This is Qingdao China, where algae is continuing to spread along China's coast. When the algae dies, it will create a dead zone in which plants and fish will not exist.
The students have yet to approach companies in the construction industry for commercialisation as they have just completed the project. However, they hope their idea will impress industry players at Singapore Polytechnic's Engineering Show next weekend.

When contacted, construction firm Penta Ocean's deputy general manager Desmond Hill commended the students for their efforts towards "sustainable construction".

"In the old days, non-structural installations like drainages and road kerbs were made from recyclable aggregates like stones," he said, but added that more studies on the long-term impact on algae's use is needed.

PHOTO: Sea of algae. "For the product to succeed it must be priced lower than normal precast components and overcome the psychological barrier of being made from waste."
Posted at 10:23 AM on July 28, 2011 by Bob Collins

"We need to assess the serviceability element - will the structure deteriorate after five years?" he said.

Concurring, Hexagroup's project director Lim Hong Leong said: "For the product to succeed it must be priced lower than normal precast components and overcome the psychological barrier of being made from waste."

A tonne of sand costs around S$42 per tonne now, down from S$60 per tonne at its peak four years ago when Indonesia banned sand exports. Ready-mix concrete, however, now costs S$109 per cubic metre, up from S$66 per cubic metre in 2007.
By Esther Ng, estherng@mediacorp.com.sg, 04:45 AM Dec 28, 2011

PHOTO: Swimming in Green Algae
Posted by Admin on 7:26 AM in bizarre, Green Algae, latest, pictures
The algae is in full bloom off of the Chinese city of Qingdao, creating a giant greet splotch measuring as much as 70 meters by 100 meters. Green algal blooms aren't dangerous to humans - although the same can't be said for red tides, which are caused by another algae species and can create harmful toxins - they do consume vast quantities of oxygen, which can be devastating to marine life. This particular swath of algae is just a tiny part of the larger bloom, which stretches some 300 miles across the Yellow Sea.
http://4.bp.blogspot.com/-u_O6d_wn-cU/TwUGz-kF2kI/AAAAAAAAQQs/bYuPga4gaTk/s1600/Swimming_Green_Algae_7.jpg

PHOTO: Swimming in Green Algae
Posted by Admin on 7:26 AM in bizarre, Green Algae, latest, pictures
Beach workers, volunteers, and visitors helped clean a carpet of algae about 1,300 feet long and 98 feet wide, China's state-run media reported. Local maritime agencies believe that rising water temperatures have supported the algae's rapid growth, according to state media.
http://2.bp.blogspot.com/-t71xQKdyD-U/TwUG0OiyzsI/AAAAAAAAQQ8/i1sy8QELZc4/s1600/Swimming_Green_Algae_10.jpg
http://www.popgive.com/2011/07/swimming-in-green-algae.html

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