User:Nellas Galadhon/sandbox

Circumpolar

• Salix vestita Pursh – silky willow
• Salix arctica Pall. – Arctic willow
• Salix glauca L. – northern willow
• Salix hastata L.

• Salix herbacea L. - dwarf willow

• Salix polaris L. - dwarf willow

Alternatives to Cement Concrete

Although the invention and use of portland cement has greatly benefited the modern world, concerns are now being raised about the high embodied energy cost required for the production of cement, high water use requirement, and the fossil fuels use for the overwhelming majority of portland cement production. If Cement production were a country it would be the world's third largest CO2E emitter behind China and the United states. Cement produces 5% of global emissions now. If developing countries expand their infrastructure to current average global levels, the construction sector will emit 470 gigatonnes of carbon dioxide by 2050. The production of cement has also increased more than 25 times since 1950. In light of these concerns alternatives to cement are gaining interest in a warming world.

Mixtures of Cement and other materials

Cement mixtures can have benefits of less unit weight and added tensile strength, insulation or other properties. They also enjoy faster marketability due to the established specifications of portland cement. However they still embody the high energy costs of the slakelime component of cement.

Aircrete

Carboncure

Hempcrete Hempcrete incorporates hemp fibres to increase the tensile strength of the concrete.

Calera in Los Gatos, CA, which has received about $50 million in venture investment. https://forterausa.com/

Alternatives to Cement

Alternatives to cement require much less embodied energy to create. They have varying engineering properties equal to or inferior to cement and face hitertho insurmountable barriers overcoming the establishment that cement enjoys in the engineering and political and economic world.

Cob

A mixture of clay sand and straw. The clay provides adhesion, the sand stability and the straw tensile strength. Cob has been utilized since ancient times. It must be kept dry, and is only suitable in arid climates or in structures with an overhanging roof.

Mycellium brick

https://www.certifiedenergy.com.au/emerging-materials/emerging-materials-mycelium-brick

Dupe

Urine, sand, calcium chloride and bacterium Sporosarcina pasteurii

https://www.wired.com/2014/01/stool-built-sand-bacteria-urine/

Ferrock

Made with steel dust reclaimed from steel mills, recycled glass, and CO2, Ferrock uses carbon dioxide as a feedstock and may sequester further CO2 during its life. Ferrock can be subjected to heat in excess of 600 degrees celsius and extremes of tortion while remaining structurally stable than can Cement. Because the material will not harden until exposed to concentrated CO2, ferrock can be formed into organic shapes and then hardened. 2

Founder of Iron Shell and inventor of Ferrock in 2004 David Stone has secured $200,000 startup capital from the EPA and built prototype structures for Tohono O'odham community college and the University of Arizona in 2015.

Criticisms of Ferrock

• Ferrous carbonate is slightly toxic: The probably oral lethal dose is between 0.5 and 5g/kg, or between 35g and 350g for a 70kg person.
• Ferrock might drive up the price of reclaimed steel and quickly absorb supplies. Fresh iron powder would be too expensive.
• Ferrock must be exposed to CO2 for some days to harden, which is a challenge on construction sites if the material were not pre-formed.
• Hydrogen gas is generated as a by-product, which can be flammable or explosive. It can also be used as a clean energy fuel.

Carbicrete

Based in Montreal, Carbicrete traps and recycles carbon by using it in blocks. They use steel slag (a byproduct of steel production) as a binding agent which is cured with carbon dioxide and water in a cold process.

In December of 2019, CarbiCrete announced that the Environmental division of Harsco Corporation (NYSE: HSC) had made a $3 million investment into the company. They also received $2 million from SQN Venture partners and $3.15 million from the Government of the Province of Quebec.

As of August 9 2021 the company reported that a Ford owned subsidiery Spin would purchase offsets of 75 tonnes.

Novacem Magnesium Silicate Magnesium oxide

Nikolaos Vlasopoulos, chief scientist at London-based startup Novacem, recieved $1.5 million in cash from the Royal Society and others. The company sold it's intellectual property to Australia's Calix and was liquidated in September 2012. Vlasopoulos now works at the cement giant Lafarge. Calix owns technology and works with partners in research and development but are currently investing in carbon capture and storage within the production of traditional cement only.

Geopolymer Cement

Geopolymer cements save carbon emissions by incorporating fly ash and by using aluminum instead of hydrated calcium. Geopolymer cement suffers the drawback of setting extremely quickly.

On Other Worlds

Lunarcrete

Aggregates on the moon would provide shelter from ionising radiation from the sun to astronauts living or working on the moon. They are made with lunar regolith and additives.

Proposed martian biolith

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0238606

Chitin and calcium carbonate

https://ascelibrary.org/doi/10.1061/9780784479179.033