A comparison of the sludge conditioning capabilities of Canavalia ensiformis and Brachystegen eurycoma

. The finely ground seeds of Canavalia ensiformis (jack bean) and Brachystegen eurycoma (achi seed) were used in the treatment of sewage sludge. They were found to improve sludge filterability and compare favourably with the traditional, ferric chloride conditioner. The optimum dosage for each sample can be determined by drawing a tangent to the corresponding curve of each sample at the point where there is a sharp break between the straight and curvilinear portion. In this work, the optimum values for C. ensiformis and B. eurycoma are 19.50% (0.39 g/cm³) and 21.5% (0.4 g/cm³) respectively. For ferric chloride, the optimum value is 25% (0.5 g/cm³). These results show that ferric chloride is still a better conditioner than both the other conditioners. However, during sludge filtration, cake and filtrate concentration increased with increasing dosages of both C. ensiformis and B. eurycoma samples. This indicates that they would be useful as conditioners if the primary product of filtration is the procurement of low filtrate concentration or high-quality cake.