Document Type : Technical Note


1 Department of Chemical Engineering, Faculty of Engineering and Technology, University of Iloin, Ilorin, Nigeria

2 Department of Chemical Engineering, Faculty of Engineering and Technology, University of Iloin, Ilorin, Nigeria - Department of Chemical Engineering, Nnamdi Azikiwe University, Awka, Nigeria


In this preliminary investigation, the production of liquid fertilizer from rock phosphate and dolomite in Nigeria using the nitrophosphate is evaluated. Rock phosphate was obtained from Sokoto state, Nigeria. Dolomite was obtained from Edo state, Nigeria. This work contains a detailed description of the procedure and the associated chemical reactions. There are also important explanations of some physical observations and their possible implications in a large scale process. The time frame for each batch should not exceed 1 h considering the reaction rates and the temperatures are likely not to exceed 80oC at any point in the process. It was observed that the potassium, phosphorus and nitrogen content of both fertilizers are similar but the calcium content of the product from dolomite was higher than the other products. Furthermore, possible process design modifications based on these physical observations are proposed in line with product quality, safety, cost and other considerations. The process was ultimately successful and recommendations were made based on several aspects of the process.


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