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UTILIZATION OF WASTES FROM THE FOOD INDUSTRY

RICE PRODUCTION

Emilia Pramova

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UTILIZATION OF WASTES FROM THE FOOD INDUSTRY

RICE PRODUCTION

1. Why Rice?2. The Rice Hull 3. Construction Sector

- Insulation- Composite Boards- Cement

4. Utilization in Other Sectors

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Why Rice

• Second largest produced cereal in the world

• World production totaled 395 million tons of milled rice in 2003

• Consumption increased 40% in last 30 years (from 61,5 kg per capita to about 85,9 kg per capita)

• International rice trade estimated between 25 and 27 million tons per year → corresponds to only 5-6% of world production.

• Forecast: global market will increase 3% per year over the mid to long term.

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Why Rice

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Why Rice

• Rice hull → 20% of the rough, harvested weightof rice

• 120 million metric tons of rice hulls generated each year globally

• A large amount of the husk is burned or dumped as waste

• Burning: 100 million tons of ash per year

• Hulls cause disposal problems → resistant to decomposition, harmful gases when burned

• Unique properties!

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Why Rice

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The Rice Hull

• Hard, protective coverings of the rice

• 20% opaline silica & large amount of lignin

• Do not flame or smolder easily

• Resistant to moisture penetration & fungal decomposition

• Do not transfer heat

• Non-corrosive

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Insulation

• Class A insulation material → wall, floor & roof cavities

• Thermal barrier → R-values greater than 3.0 per inch

• No need for flame & smolder retardants and fungicide

• High concentration of opaline silica on outer surface impedes atmospheric transfer of moisture into hull

• Hardness (opaline silica) + elasticity (lignin) + peculiar bonding → resist settling & compression.

• Technology exists → engineered lumber products, sugarcane rind

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Composite Boards• Composite boards → usually wood & cement but rice hull ash

(RHA) can substitute for cement

• RHA is high in silica!

• Usually wood fibres absorb water → can swell

• RHA mixed with cement is very porous → water enters the ash and not the wood, stopping the wood from swelling.

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Cement Industry• Low cost building blocks → replacement of 50% of Portland

cement with RHA leading to a concrete cost reduction of 25%

• Indonesian company used a mix of 10% cement, 50% aggregate and 40% RHA plus water → test blocks with an average compressive strength of 12N/mm

• Normal blocks without RHA have an average of 4.5 to 7N/mm

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Cement Industry• Enhancing properties of cement

• Portland cement produces an excess of lime Adding RHA pozzolan → combines with lime in the presence of

water → stable and more amorphous hydrate (calcium silicate). Stronger, less permeable and more resistant to chemical attack.

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Utilization in Other Sectors

• Bio packaging from rice hulls, recycled paper & fungus from Ecovative design http://www.ecovativedesign.com/

• Bio dishware that is temperature-proof from EnviroArc http://www.enviroarc.net

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Utilization in Other Sectors

• Steel industry → in the production of high quality flat steel (automotive body panels and domestic 'white goods' products)

• RHA → excellent insulator, having low thermal conductivity, high melting point, low bulk density and high porosity.

• Excellent `tundish powder' → insulate the tundish, prevent rapid cooling of steel & ensure uniform solidification in the continuous casting process

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Utilization in Other Sectors

• Control of insect pests in food goods storage → RHA prevents insect attack in stored food stuffs

• Studies with Indonesian soy beans (infested by Graham bean beetles) → mixing 0.5% ash to soy bean

• RHA also shown to keep stored potatoes free of the Potato tuber moth (Phthorimaea operculelle) for up to 5 months of storage

• Insects irritated by high levels of silicon and the needle like particles

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Utilization in Other Sectors

• Soil ameliorant → RHA helps break-up clay soils and improve soil structure. Porous nature assists in water distribution. Also increases PH of soil.

There are other uses for RHA which are still in the research stages:

• in the manufacture of roof tiles• as a free running agent for fire extinguishing powder• an abrasive filler for tooth paste• a component of fire proof material and insulation• as a beer clarifier• extender filler for paint• production of sodium silicate film

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References• Build Green with Recycled Rice. (2008). Video retrieved from

http://www.youtube.com/watch?v=dF2Y6tGzZOI• Build Green with Recycled Rice. (n.d.). Recycled Rice. Retrieved January 24,

2010, from http://recycledrice.org/• Lee, J. (n.d.). Rise Waste May Build New Asian Homes. ANU Reporter.

Retrieved January 24, 2010, from http://info.anu.edu.au/mac/Newsletters_and_Journals/ANU_Reporter/_pdf/vol_29_no_01/rice.html

• Olivier, Paul. (n.d.). Rice Hull House. Washington, Louisiana 70589: Engineering, Separation & Recycling LLC. Retrieved from www.thelaststraw.org/backissues/articles/Rice%20Hull%20House.pdf

• Rice Husk Ash Market Study (Report for renewable energy technology exporters in the UK). (2003). . DTI New and Renewable Energy Programme.

• Rice Market. (n.d.). UNCTAD Market Information in the Commodities Area. Retrieved January 24, 2010, from http://www.unctad.org/infocomm/anglais/rice/market.htm

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THANK YOU!!

UTILIZATION OF WASTES FROM THE FOOD INDUSTRY

RICE PRODUCTION