Palm kernel incinerated ash as low cost concrete component
- Authors: Agbenyeku, Emem-Obong Emmanuel , Okonta, Felix Ndubisi
- Date: 2014
- Subjects: Lightweight concrete , High strength concrete , Incineration
- Type: Article
- Identifier: uj:5058 , ISBN 9781614994657 , ISSN 9781614994664 , http://hdl.handle.net/10210/13620
- Description: The incorporation of commercially available fly ash (FA) as low cost material in concrete has long been established. Large quantities of FA are utilized for research and field applications because of the pozzolanic characteristics. One of many pozzolanic materials is palm kernel incinerated ash (PKIA). The abundance of PKIA as an agricultural waste material in West Africa obtained by the incineration of palm kernel husk and shells in milling boilers paved way for this study. Specimens containing 50%PKIA were cast and cured both in water and air and their compressive strength and shrinkage behaviours were investigated with and without the addition of superplasticizer (hydroxylated carboxylic (HC) acid) in comparison with controlled specimens containing 100%OPC. Results showed that the strength development in PKIA green concrete at all ages of curing; 7,14 and 28 days were lower than OPC concrete. On the addition of superplasticizer, strength of 36.9N/mm2 was observed for specimens with superplasticizer as against 31.7N/mm2 for specimens without superplasticizer on the 28day. The water curing method produced the best results while the predicted shrinkage strain of the green concrete in accordance to ACI 209R-92 standard was higher than the control specimens.
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Incineration as a potential solution to Africa’s plastic waste challenges? A narrative review
- Authors: Mazhandu, Z. S. M. , Muzenda, E. , Belaid, M. , Mamvura, T. A. , Nhubu, T.
- Date: 2020
- Subjects: Incineration , Life Cycle Assessment , Plastic waste
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/458865 , uj:40776 , Citation: Mazhandu, Z.S.M. et al. 2020. Incineration as a potential solution to Africa’s plastic waste challenges? A narrative review.
- Description: Abstract: Africa is considered the second most polluted continent and it will contribute the highest amount of waste into the world’s oceans by 2035. A paltry 4% of the total municipal solid waste (MSW) generated in Africa is recycled and yet 70-80% of the MSW is recyclable. In addition, 90% of the waste that is generated is dumped at uncontrolled landfills while 10% is illegally burnt. Africa has accumulated over 130 million tonnes of plastic waste on its landfills. The poor recycling statistics of the continent means that Africa is missing out on the benefits that plastic waste can yield such as job creation and energy generation; both which are lacking in Africa. The objectives of this review are therefore to assess whether incineration can be considered in the management of plastic waste in Africa based on past life cycle assessment studies; to determine the risks associated with incineration as well as evaluate threats to its success. Data was sourced using keywords and phrases in academic databases and grey literature. The results show that opportunities exist for Africa to manage its plastic waste sustainably and therefore, landfilling of plastic wastes is not the solution due to the risk of spontaneous fires that release harmful toxins. In conclusion, as the continent navigates the path to “zero waste to landfills” in line with circular economy principles; it is time for waste to energy technologies such as incineration to be considered in waste management systems. Life cycle assessments (LCAs) within the African context need to be carried out as they are lacking, in order to determine how incineration or other treatment methods such as pyrolysis and use of plastic wastes in cement kilns and blast furnaces can be successfully implemented without increasing eco-toxicological and human toxicological impacts.
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