February 25, 2013

Manufacturing concrete from recycled materials earns award

CONCRETE FEATURE

PETER CAULFIELD

correspondent

Lock-Block Ltd., a Richmond, B.C. company that manufactures concrete products from recycled materials, recently won a TechGREEN Award from the Applied Science Technologists and Technicians of B.C. (ASTTBC).

“The ASTTBC Awards Committee felt that (Lock-Block) was very deserving of the TechGREEN Award and felt that (company founder and president) Jay Drew... should also be recognized for his leadership in green technology,” said ASTTBC executive director John Leech.

He said Lock-Block met almost every one of the numerous and detailed criteria for the TechGREEN Award.

They include demonstrated leadership in green technology, positive impact on sustainable living, significant environmental benefits and a major impact on energy conservation.

ASTTBC is an association of 10,000 professional technologists, technicians and technical specialists in engineering and applied science technology in British Columbia.

The association has been giving the TechGREEN Award for four years.

Lock-Block, formerly United Lock Block Ltd., won the award just as it was about to mark its 30th year in business.

Founder Jay Drew’s idea for using recycled materials to make concrete goes back to when he was a division engineer for Lafarge Canada Inc. in the 1970s.

“When I had the time, I used to think of ways to make good use of all the concrete that was left over in the ready mix trucks at the end of the day,” Drew said.

“I designed a metal form into which the trucks could pour their left-over concrete. It looked like a steel cardboard box without a bottom.”

The resultant concrete blocks were sturdy enough, but the original dimensions – two metres by <0x00BE> metre by <0x00BE> metre – were not suitable for all applications.

“So, I modified the steel forms to make them twice as long and as wide,” Drew said.

The blocks weighed more than 4,000 lbs each.

When he discovered his employer wasn’t as interested in his innovation as he was, Drew decided to start his own business in order to capitalize on the idea.

“I made the steel forms myself and distributed them to ready mix companies around the province,” he said.

“Lock-Block sold the concrete blocks that were made from the companies’ left over concrete and we split the revenues 50/50. Instead of dumping the concrete, they turned what had been a cost into revenues.”

Drew estimated some companies were able to earn an extra $10,000 per month from selling blocks made from the concrete they used to throw out.

Because of the high cost of transporting heavy concrete blocks, most of the customers were located in the same parts of the province where the blocks were made.

Lock-Block quickly proved to be successful.

It was so successful that it attracted competitors.

As a result, the company changed its business model and now all of its production is done at its plant on an eight-and-a-half acre site on Mitchell Island in Richmond.

After his company’s success with the lock-blocks, Drew went on to make other products.

For example, rubble and waste from demolition sites are fed into recycled crushing, screening and washing equipment and out come pre-cast aggregates.

And, recycled latex paint is blended into some pre-cast products.

In total, Lock-Block produces about 50 different concrete products and licences its technologies around the world. <0x2028>

Cengiz Guldemet, manager of the Burnaby branch of Metro Testing Laboratories Ltd., which inspects and tests construction materials, said there is an increasing use of recycled and low-carbon materials to make concrete, and there will be more in the future.

“For example, silica fume and blast furnace slag, which are both by-products of the steel-making process, are being used increasingly to make concrete,” he said.

“But, they are not being used much in western Canada because there is little steel making here.”

In this part of the country, fly ash is being used increasingly to replace cement in the manufacture of concrete.

“Fly ash can replace cement from a standard 20 per cent up to as much as 70 per cent, depending on the strength and weight requirements of the concrete,” Guldemet said.

“Fly ash is being used a lot to replace cement in LEED projects.”

The fly ash used to make concrete is created in coal-generated power plants in western Canada and the U.S. and shipped to B.C. by train.

In addition, limestone, another low-carbon material, is being used to replace cement in concrete.

Portland-limestone cement is said to reduce greenhouse gas emissions associated with traditional cement manufacturing by about 10 per cent.

Limestone is also mined in B.C., on Texada Island.

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