Plastic waste use in the blast furnace as a reducing agent

Abstract: Steel is among the most essential materials in construction, making its manufacture equally important. Steel is manufactured either via an integrated iron and steel making route characterised by the Blast Furnace (BF) and a Basic Oxygen Furnace (BOF), smelting followed by a BOF or in an electric arc furnace. The objective of this paper explores the possibility of using plastic waste in Africa as an alternative reducing agent to coke in the Blast Furnace; a recycling practice that is commonly done in Japan and Europe. There are many benefits that can be accrued environmentally, operationally and economically when using waste plastics in the BF. The hydrogen content in waste plastics is almost three times more than that in pulverised coal making it a better reducing agent environmentally and economically. Plastic waste has a higher calorific value and less impurities, which results in energy savings and less dioxins and furans in the process. In addition, bearing in mind that over 130 million of tonnes of plastic waste are currently in Africa’s landfills, utilising waste plastics in the BF will result in savings in landfills airspace, prevent financial losses incurred through dumping valuable recyclables, protect the environment and the public because if spontaneous fires start in landfills then toxic fumes such as furans and dioxins, cannot be generated if the landfills are plastic free. With such evidence on hand, plastic waste use in the BF presents an untapped beneficial opportunity not only for the continent of Africa but other continents such as North America where landfilling is rife

Incineration as a potential solution to Africa’s plastic waste challenges? A narrative review

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

Consonant assimilation in isiNdebele: A distinctive feature approach

The article discusses consonant assimilation on isiNdebele nouns, and examines that within the parameters of the Distinctive Feature approach. The main submission in this study is that consonant assimilation is local, homorganic and that it is found in the construction of class 9 and class 10 nouns. The terminal alveolar nasal consonant [n] of classes 9 (iN-) and 10 (iziN-) merges with the initial consonant of the following noun stems to give a homorganic sound. Consonant assimilation is threefold; place assimilation, manner assimilation and phonation assimilation. The article also established that assimilation is adjacent, partial, bidirectional, and is either progressive or regressive.Key words: manner assimilation, phonation assimilation, place assimilation, trigger sound and target soun