how to make a clay brick in the lab 2

[budaryah]

I am a researcher in civil engineering materials specializing in asphalt mixes. I am doing research in recycling idusterial solid waste as a construction material.I have used waste materials in concrete and asphalt in the past. I am trying this time to utilize two wastes in clay bricks which is a new area to me. The first waste is a spent Zeolite catalyst pwder (Ecat) generated from oil refinary operations. The seconed waste is an air dried solid sludge cake obtained from the textile effluent treatment plant, which will be pulverized before mixing with red clay.

I am thinking to prepare 70X70X70 mm cubes and fire them in a muffel furnace at different emperatures. I am not sure how to properly mix the materials to get red of all the air inside and avoid cracking during the firing process. Any ideas, standards, and specifications for the mixing, firing and the testing to evaluate the new products and compare them to the standard normal clay bricks ?

 

[Ron]

Go to a local craft shop that provides instruction in pottery and has a kiln on site. They can tell you how they mix their clay and keep the air out for proper firing.

If you consult the industry, you'll likely only get info on large batches, which will sometimes not work well with small batches and your available equipment. The local crafts instructors are used to working with small batches and minimal equipment.

 

[concretemasonry]

Clay brick have an astoundingly wide range of properties depending on the raw materials (the clay particles - shape and chemistry). This is compounded by the firing process (time and duration) AND the timing of the cooling process. Some clays can become vitrified.

Consequently, any lab attempts will be impossible to correlate to a new production process unless the material and their properties can be correlated and combined and matched to a typical process.

There is very little correlation between pottery and fired clay brick, especially of the shape and configuration (cored vs. solid) is included. The "red" color is often an indication of the amount of iron in the brick, but other minerals can be combined to give the "red clay brick" appearance.

Dick

Engineer and international traveler interested in construction techniques, problems and proper design.

 

[budaryah]

Many thanks Ron(Structural) and Dick(Concrete Masonary) for answering my question.

The clay I am using will be supplied to me in a powder form by a local brick making factory.

Any body is aware of the relavent standars or specifications for quality control in the lab.

 

[bimr]

An extrusion process is usually used in brick making process to form the bricks. Prior to extruding, the mixed raw materials are passed through a vacuum chamber to reduce the amount of air in the brick mix. This results in a denser, more homogeneous product.

http://www.glengerybrick.com/about/manufacturing/index.html

 

[concretemasonry]

I would suggest working with a clay brick producer to extrude some typical samples under real manufacturing conditions, but they may not be willing to adjust the firing conditions because of the time involved in changing a production process that has a tremendous thermal inertia. An alert - the firing temperature and duration is critical to any similar product because of the chemistry and expansion.

There are some progressive manufacturers that are faced with limited availability of natural resources.

Engineer and international traveler interested in construction techniques, problems and proper design.

 

[saplanti]

To my knowledge, cooking by steam or any other nature is the way.

Ibrahim Demir

 

[budaryah]

bimr(Civil/Environmental): I looked at the link you provided, the problem is that I am working with small quantities in the lab, so I have to find a way where I can extrude the sample in a vacuum chamber to get red of the air inside, but i havent found a way yet!

(Concretemasonr): I contacted a manufacture of bricks,he will supply me with ground red clay free of charge. However, he cant mix the stuff for me in the plant or fire it, because of small quatities of waste materials I have, and because he cant disturb his production process.

Ibrahim demir : I think steem cooking you refered to is good in concret, this is an autoclaving process that wel speed up the hydration rate of concrete. In clay we have to fire ( burn ) the brick, it is a completely different mechanism.

 

[ewh]

I don't know how applicable it is to returning a result you can use, but Ron may have a good suggestion; could you "throw" the clay to eliminate any trapped air, much the way a hobbiest would?

Technically, the glass is always full.

 

[budaryah]

ewh(Aerospace): many thanks for your response. I did not understand exactly what did you mean by "throwing the clay". I decided however, to nead the paste by my hands and then use a rod to compact the clay in the small cube moulds (70x70x70mm)and finaly exert some pressure on the material by a plunger that fits exactly in the moulds. I shall start as soon as the clay arrive, I hope this will work !

 

[ewh]

"Throwing" is fairly literal; you repeatedly throw a hunk of clay down firmly, forcing the air to the surface.

Technically, the glass is always full.

 

[concretemasonry]

budaryah -

Make sure you fire the clay samples at the proper temperature for chemical properties of the clay sample. The firing temperatures have an effect of the properties of the finished product. The dimensions of the samples may also have an effect on the properties and dimensional stability.

Trying to match lab samples with the real world is a very difficult challenge.

Dick

Engineer and international traveler interested in construction techniques, problems and proper design.