As the population is ever-increasing the demand for clean, safe drinking water all over the world is constantly rising. It is no surprise that this has resulted in increased numbers of water treatment plants all over the world. The increased number of water treatment plants has led to increased levels of sludge being produced. The disposal of this sludge can cause problems, as there is just nowhere available to store it. The Universiti Teknologi in Malaysia took on a project to try to find a solution to this problem - to introduce a 'sludge management concept'. This water sludge is not considered to be hazardous, it is a by-product of water treatment. It has been discovered that this product can be used to make so-called 'eco-pottery'.The fact that it is not considered hazardous is good news as it means it can be re-used. Several tests were completed in laboratories on the chemical composition, energy properties and mineral content of the water treatment plant sludge. It was found that it would be suitable for use in pottery products. This means that not only does the sludge get re-used, the problem of storing it is also solved. The sludge could be used in the structural ceramic industry, meaning it could be used to make bricks. Any organics substances in the sludge are burnt off and heavy metals are safely contained within the "pottery". Other by-products from Water Treatment Plants are more hazardous such a fecal sludge. The Department of Water and Sanitation in Developing Countries (SANDEC) have written a guide on the subject. Sludge is created during the filtration process in treatment plants, it is made from the accumulated solids removed from the sedimentation basin / setting tank. In the United Kingdom sewage sludge is recycled in the following ways: - 62% is used as bio-solids A bio-solid is a nutrient rich material and often used as a fertiliser in agriculture. Sludge can be used to produce biogas, a fuel for heating and energy. - 19% is incinerated - 11% is used in land reclamation Land reclamation is the process of creating new land. Sewage sludge can be used along with other materials including sand to form new land masses. The sludge in this case acts as a fertiliser and provides a base for new plants to grow. - 7% is used for other purposes - 1% goes to landfill A similar project in Spain by Eco Ceramics found that there were many benefits to using Water Treatment Plant sludge in the manufacture of ceramic products. The environmental benefits include a reduction in the disposal of sludge, a reduction of carbon dioxide emissions and it is thought that using sludge could result in a 6% decrease in the net energy consumption within the ceramics industry. The only disadvantage Eco Ceramics found was that during the drying process, there was a smell produced which some found unpleasant. So what do you make of this? Would you be happy to have your house bricks made using waste products from water treatment plants? I think it is a great idea to stop more waste going to landfill.
July 29, 2014
In: Industry News
Tags: Eco Pottery, Pottery, Ceramics, Industry, Water Treatment Plant, Water Treatment Waste, Sewage Sludge, Water Sludge, Spain, Malaysia, Land Reclamation, Landfill, Recycling