The cheapest and most rapidly available metal for agro‐processing equipment fabrication in Nigeria is plain carbon steel. However, there are some aggressive ions present in raw agricultural and food products, which may attack the steel components of these processing machinery, resulting in their untimely failure in service. The present study investigates the effect of fluid squeezed from cassava tuber on the corrosion behaviour of mild steel.
The investigation involved periodic weight loss measurements of 0.8 per cent carbon and 0.36 per cent carbon steel rods as they were exposed to cassava fluid. The relationships between loss in weight of the exposed samples and exposure period were determined. Models were developed to relate corrosion rate in each environment with total surface area and exposure period.
The results show that 0.36 per cent carbon steel was less affected by corrosion than 0.18 per cent carbon steel, with corrosion intensity in both cases, increasing with duration of immersion. Generally, there was low level of corrosion resistance (high corrosion rate) by the two steel materials. The correlation coefficient between the experimental values of corrosion rates and predicted values (using the developed models) was high.
In food and agricultural industries, product quality, health and sanitation issues are the major concerns. The industries cannot tolerate corrosion deposits in the manufactured products. Hence, material selection for machinery fabrication is essential. In line with this, the results of this study indicate that mild steel materials are unsuitable for use in cassava processing without some forms of surface treatment.
