Eco-Cement and Eco-Concrete Environmentally Compatible

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The most popular buzzword in construction today has also
  pervaded almost every other aspect of modern
  life: green. Whether it is applied to building, living, or
  eating, everyone is attempting to reshape their habits in
  an environmentally-friendly manner.
Limestone is crushed to create cement powder. Also,
  since limestone is so common around the world, it
  can generally be harvested and processed locally,
  which reduces the amount of resources needed to
  transport the cement from the plant to the
  construction site. In addition, cement can be made
  or partially comprised from waste products from
  various production processes such as fly ash, silica
  or slag
How Concrete Reduces the Carbon

 Concrete acts as a natural insulator, or better said, helps
 to adjust to environmental conditions. Concrete retains
 heat, which can significantly help with homeowner's
 heating and cooling needs. It can absorb warmth from
 the sun in the winter months and retain the heat inside,
 while keeping in the cool air in the summer.
One of the most popular features of concrete is its durability,
  which is also one of the main factors in its being a green
  building material. Sustainable building and living emphasizes
  long-term solutions and products over cheap, short-term
  products that will be thrown away and add to the waste
  management issues that already exist. Concrete can last for
  many times longer than conventional building materials, such
  as wood or drywall. It is very resistant to common causes of
  deterioration in homes such as insect activity, rot, rust and
  even fire.

Overall, concrete can offer many homeowners the sustainable
  option they want, while giving them the cost effectiveness and
  structural strength they require. Contractors, meanwhile, may
  find that they are already employing more green business
  practices than they had ever imagined.

The rising trend to build more efficiently with less impact on the
  environment has spurred a lot of interest in the unique qualities of
  concrete. Green building includes reducing waste from products
  used, finding non-toxic product alternatives, and using recycled and
  local materials. These environmentally-conscious choices are readily
  available when designing and building with concrete. Below are
  details of the eco-friendly strategies concrete offers for sustainable
  and environmentally friendly living
 Green concrete floors

 Green concrete countertops

 Green concrete homes
Top Reasons to Go Green with
 Concrete Floors

 Design Versatility
 Energy Efficiency

 Easier Breathing

 Economy

 Durability and Resource Conservation
Green Concrete Countertops
Because of its low impact on the environment, concrete is
 one of the greenest countertop materials you can use.
  Green Concrete Homes

The Healthy House Institute reports that
indoor air pollution is the cause of about
50% of illnesses. Common sources of this
pollution include outgassing from toxic
paints and finishes, carpeting,
manufactured wood products containing
glues high in formaldehyde, dust mites,
mold spores, mildew, and some cleaning

 Concrete floors, stained with nontoxic pigments, are a healthier alternative to
 carpeting because they do not emit harmful VOCs and are easy to sweep
 clean. In fact, VOC emissions from concrete building products are much lower
 than those for most other building materials, according to PCA. The use of
 natural lime-cement plaster wall finishes and concrete countertops can also
 significantly reduce total VOC concentrations inside a home.
Key Technology in Eco-cement
Incinerator ash generally also contains a high concentration
  of chlorides and a small amount of heavy metals.
  Therefore, decomposition, removal, or enclosure of these
  substances is the key to the success of this project.

      The metals vaporize in the form of chlorides through
  the burning process and are caught as kiln dust in the
  bag filter. The heavy metals are then extracted from the
  dust through the metal recovery process and delivered to
  a smelter for refining. This makes the eco-cement
  process a complete recycling system for municipal and
  industrial wastes.
The targets in development of eco-
  As much as 50% of the raw materials have to be replaced by
   incinerator ash or other waste
   materials such as sewage sludge.
  The cement has to have general wide use.
  Both the manufacturing process and the
   products have to be environmentally-friendly.
  The entire process has to be a complete

     recycling system.
Raw mix and incinerator ash
Incinerator ash composition

                     Major components(%)
   ig.loss Sio2    AL2O   Fe2O    Cao         Mgo        So3    Na2O       K2O        Cl
                   3      3

   11.0    22.9    19.7   5.6     30.4        4.8        2.1    3.3        2.6        8.5

                  Minor components (%, ppm)

   Tio2    P2O     Zno    Cuo    Cr      As         Cd    Hg    Pb     F         Cn         Pcb

   0.9     1.8     0.6    0.6    438     55         11    3.5   311    120       Nd         Nd
Typical Mix Design of Raw Meal (%)

Type of cement          Incinerator          Limestone         Clay    Ferro M.
Portland cement type         58.2                40            1.3        0.5           -
Rapid-hardening              52.2                45            2.2        0.3          0.3

                  Composition of eco-cement
                            Chemical composition(%)
 Type of cement   ig.loss   Sio     Al20   Fe2   Cao     Mgo     SO3   Na20     K20    Cl
                            3       3      O3
 Portland         0.6       19.1    8.1    4.5   62.7    1.4     3.7   0.05     0.00   0.04
 cement type
 Rapid-           0.8       15.5    11.0   1.9   58.5    1.4     8.8   0.60     0.00   1.00
 hardening type
 NPC              0.6       22.2    5.1    3.0   63.8    1.4     2.0   0.30     0.20   0.00
                  Mineral composition(%)
Type of cement     C3S   C2S   C3A   C11A7.Cacl2   C4AF   Caso4

Portland cement    49    12    14                  13     7.7
type                                      -
Rapid-hardening    44    11                        8      15.0
type                           -         17
NPC                56    19    9                   9      3.4
                   Project of eco-cement
   1991 Starting the eco-cement project
   1994 50ton/day Test Plant Operation
   2001.4 350ton/day (95,000ton/year) 1stCommercial Eco-cement
    plant 90,000ton/year of incinarotor ash from 2,500,000 people can be
    treated in Ichihara Plant (Chiba Prefecture)
   2004 800ton/day (200,000ton/year) 2ndCommercial Eco-cement
    plant started to construction
   2006 2ndPlant will start to operation.
 cement industry has the potential to make the best use of
   waste and to purify the environment. This eco-cement
    and concrete technology is divided into four specific

i)Utilizing waste materials as alternative fuel and raw materials (AFR).
   An example includes “eco-cement” developed by Taiheiyo Cement
   Corporation in Japan.

ii) Purifying the environment with concrete photocatalyst
road, whereby TiO2decomposes NOx with ultraviolet rays.

iii) Encouraging natural flora and fauna, with bio-sowed
Concrete technology.

iv) Reducing the heat island phenomenon in urban areas
through sowed concrete technology.
  1.Waste Material (AFR)
  Use in Cement Industry

AFR Alternative Fuels and Raw Materials

                                    World cement average:0.8 to 1.0
% fuel CO2 by sector cement in cl
                                    ton CO2/t-cementGlobal cement
process CO2

                                    industry:5% of global
                                    CO2 emission


                                    Cement industry
RESIDENTIAL=15                      =largest source of
                                    manufacturing industry
2.Purifying the environment with
  concrete photocatalyst road,
  whereby TiO2 decomposes NOx
  with ultraviolet rays
 Air pollution of NOx by cars has become a
  seriomolecules on the surface when the
  ultraviolet rays light (sun light) the
 Rapidly NOx in the air is oxidized into nitric acid
  by active oxygen molecules.
 us problem.
 The TiO2 photocatalyst creates active oxygen
Application of photocatalyst TiO2 on wall

 Application of photocatalyst TiO2 on road
3.Encouraging natural flora and fauna,
 with bio-sowed concrete technology

 Background

Ministry of construction of Japan changed a law
 concerning to management of river for the
 benefit of amenity of the river landscape in 1997.
     The ministry is focusing on the improvement
 and maintenance of the river environment for
 natural flora and fauna in additionto previous
 mandates of flood control and forestry
4.Reducing the heat island
 phenomenon in urban areas through
 concrete technology sowed
Field of Porous Concrete

• Sowed concrete
• Permeable concrete
• Insulation block
• Humidity control block
• Photocatalyst pavement
• Crab libable sea wall
• Fish bank, Sea grass bed

Essentially, pervious concrete is a structural concrete pavement
 with a large volume (15 to 35 percent) of interconnected voids.
 Like conventional concrete, its made from a mixture of
 cement, coarse aggregates, and water. However, it contains
 little or no sand, which results in a porous open-cell structure
 that water passes through readily
   How Pervious Concrete Works
When pervious concrete is used for paving, it can take in storm water at a
  rapid rate of 3 to 5 gallons per minute per square foot of surface area,
    which exceeds the flow rate needed to prevent runoff in most rain
        events. The rainwater may be stored in a coarse gravel layer
   underneath the pavement or allowed to percolate into the underlying
   soil. Because the pavement itself acts as a retention area, it helps to
 prevent much of the polluted runoff that normally occurs with impervious
  pavements. The filtration process also helps to purify the water. As the
    water percolates through the open cells of the pavement, aerobic
      bacteria in the voids help to break down harmful pollutants and
Role of Cement and Concrete

  The20th century has been the century of concrete.
  Throughout the 20th century, concrete has contributed to
    human society as the basic construction material.

Now, towards the 21st century, the cement industry will
 become a greater contributor to society by taking on a
 second role as an environmental system manager. The
 cement and concrete industry will also provide a solution
 to municipal and industrial waste problems and to
 manage sound environment.

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