Eco-pottery product from water treatment sludge

July 23, 2014
Pottery making in Sarawak, Malaysia. Credit: Colin Charles / Flickr

Sludge is a by-product of water treatment. Sludge is produced during the clarification and filtration process in the water treatment system. It is also produced from the accumulated solids removed from sedimentation basin or settling tank.

The increasing number of water treatment plants has led to a considerable increase in generation. The disposal of sludge from water treatment operations poses a problem in Malaysia.

The problem is acute because of the scarcity of space to store the sludge. The advantage of water sludge is that it is not considered as hazardous waste.

The objective of this project is to reduce the environmental impact generated by the sludge coming from the Water Treatment Plant (WTP), through a new sludge management concept that introduces a method that re-uses sludge as raw material for the structural pottery industry.

Pottery is the type of ceramic material, which the American Society for Testing and Materials (ASTM) has defined as wall fired ceramic wares that contain clay when formed except technical, structural and refractory product.

The term pottery is also used for a technique involving ceramic, where clay is mixed with other minerals and is formed into objects, including vessels generally designed for utilitarian purposes.

Ceramics have characteristics that enable them to be used in a wide variety of applications including i) high heat capacity and low heat conductivity, ii) corrosion resistance, iii) electrically insulating, semi-conducting, or super conducting, iv) non-magnetic and magnetic, and v) hard and strong, but brittle.

The Eco-pottery is made from water treatment sludge. During the process, the organic substances in the sludge were eliminated through burning, while the heavy metals were safely contained in the product.

Furthermore, energy is saved during the production process since sludge is used as combustion during the burning process. Technically the Eco-pottery has demonstrated that the WTP sludge could be viably used in the mixture to produce pottery. The , the energy properties of the sludge and the mineral contained in the sludge were analysed in a laboratory.

Chemical composition is vital because of its effect on the product behaviour. X-ray Fluorescence (XRF) and Total Nitrogen Measurement (TNM) determined the chemical composition of water treatment sludge.

The physical characteristics of the sludge were also tested. The test conducted is moisture content and plasticity of the sludge. The mineral compositions were determined by X-ray Diffraction (XRD) was silica, kaolinite, muscovite, iron oxide and iron hydrogen phosphate.

Water treatment sludge contained high concentration of free silica. The Eco-pottery was made using throwing technique. The samples are then pressed into mould to make prismatic bar each mark with 100mm measurement. Linear shrinkage was determined by measuring the length of the samples before and after the firing stage using a calliper with a precision of ±0.01 mm. Water absorption was done according to the Malaysian Standard, MS ISO 10545-3:2001. Firing properties were obtained by observing whether potteries resistant to low and high temperature.

The results show that water treatment sludge can be used as raw materials in the production of pottery products. This will provide reuse option to sludge.

Explore further: Energy from microbes for drying sewage sludge

Related Stories

Energy from microbes for drying sewage sludge

August 13, 2012

A new biodrying process from Siemens quickly converts sewage sludge into a usable form while saving energy. When dried with the new process, sludge from wastewater treatment can be used as fertilizer, dumped in landfills ...

TU Delft's promising water-treatment technologies combined

September 6, 2012

Thanks to research by Mari Winkler, it should now be possible to integrate two successful TU Delft technologies for the treatment of waste water with bacteria, Nereda and Anammox, into a single plant. On Wednesday 5 September, ...

Purifying sludge through oxygen-based digestion

April 29, 2013

An additive for oxygen-based processing of sludge may be useful in specific cases in lowering the environmental impact of waste water treatment for the meat and dairy industries.

New material to enhance crop yield

December 16, 2013

Researchers at the UPM have developed a carbonaceous material from sewage sludge that when applied to soil can help to improve its quality.

Turning mining wastewater into rainwater

June 12, 2014

A new cost-effective technology to treat mining wastewater and reduce sludge by up to 90 per cent has been used for the first time at a commercial mine. The technology, called Virtual Curtain, was used to remove metal contaminants ...

Recommended for you

Amazon deforestation leaps 16 percent in 2015

November 28, 2015

Illegal logging and clearing of Brazil's Amazon rainforest increased 16 percent in the last year, the government said, in a setback to the aim of stopping destruction of the world's greatest forest by 2030.


Adjust slider to filter visible comments by rank

Display comments: newest first

4 / 5 (1) Jul 23, 2014
recursive chamber pots
5 / 5 (1) Jul 23, 2014
The organic portion (low density, low settling velocity) of the sludge can be separated from the higher density minerals portion and collected for sterilization (heated to 72 °C (161 °F) for at least 15 seconds in a solar pasteurizer), after which it makes a fine organic fertilizer.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.