بفضل من الله تمكن الباحث يوسف نبيل يوسف من تحقيق نجاح في معالجة مياه الصرف الناتجة عن طحن زيت الزيتون بطريقة سهلة ورخيصة. ونال ببحثه درجة الماجستير في العلوم البيئية. المرفق يوضح النتيجة المتميزة التي توصل إليها الباحث، باستخدام مواد طبيعية ورخيصة، كما يتضح من الملخص التالي:
 
Olive mill wastewater (OMW) is a liquid by-product contains toxic compounds generated during olive oil extraction industry. The OMW is representing a severe environmental problem due to its highly polluting organic and inorganic load. Several studies have been devoted to build up efficient treatment technologies for OMW through various kinds of physicochemical and biological pretreatments. However, these treatments are in many cases not economically feasible, due to short olive oil season, typical biennial olive harvest cycle, and small isolated area of olive mills. In this study, processes used to treat OMW were chosen according to technical feasibility, economics, simplicity, societal needs and political priorities. Different type of successive columns contain different type of natural materials were investigated for its treatment efficiency; however, the successive columns of gravels, fine sand, and mixture of acidified cotton using diluted acetic acid and Zeolite (2 cotton: 1 Zeolite (wt: wt)), and then treatment with activated charcoal and lime was found to be the best treatment in terms of the quality of water obtained. The results indicated that this method is efficient in reducing the concentration of nitrate, boron, potassium, phosphorus, turbidity, total fat, and electric conductivity in OMW by about of 78.0, 92.4, 66.6, 48.3, 96.8, 93.3, and 48.4% respectively.  Most contaminants were removed from OMW on third column (zeolit column); this is due to the high sorption affinity of zeolite on its specific sites in the channel/cage systems. The activated charcoal was found to be efficient on colloidal and soluble organic particle removal; on the other hand, the lime was used to raise the treated OMW pH to reach 5.1 instead of 2.9. This simple method enables us not only obtain environmental friendly treated OMW but also treated water can be used for irrigation with some degree of restriction due to salinity.