Assessment and heavy metal behaviors of industrial waste water: A case study of Riyadh, Saudi Arabia

Journal Article

Al-Farraj, Abdullah S. . 2013

• نوع عمل المنشور: بحث
• رابط المنشور على الويب: http://www.iaees.org/publications/journals/piaees/articles/2013-3(3)/assessment-...
• الوسوم: industrial effluents; heavy metals; chemical constituent; Riyadh city
• المجلة \ الصحيفة: Proceedings of the International Academy of Ecology and Environmental Sciences
• رقم العدد: 3
• رقم الإصدار السنوي: 3
• الصفحات: 266-277

مستخلص المنشور

This study focuses on the monitoring and chemical analysis of two pathways, unpadded and open drain canal, of the surface industrials effluent on industrial city of Riyadh city, Saudi Arabia. The distribution of the chemical constituents (Major, Minor, and Heavy metals) is determined and compared with Saudi Arabia and USEPA standards.  The obtained results indicated that most collected water samples exceeded the acceptable limits set by standards used for most parameters determined. The concentrations of total suspended solids, Fe, Mn, Zn, Cd, Ni, Pb, Mo, As, B, NO3-, and NH4+ in industrial effluents decreases away from the point source of pollutions. On the other hand, the SAR , RSC,  total hardness, and  soluble ions (Ca2+, Mg2+, Na+, K+, Cl-, CO32-, HCO3-, and SO42-), remained constant. Most heavy metals on wastewater effulent were above permissible limits. On the other hand, making filtration of wastewater decrease the heavy metals concentration to be within permissible limits. The highest average metals concentration in digested effluents for deferent locations and sampling periods were Fe (17.1 mg L-1) followed by Mo (11.6 mg L-1), then Co (0.03 mg L-1). However the Mo recorded the highest value in filtrated effluents (23.2 µg L-1) followed by Fe (21.6 µg L-1), then Cd (8.02 µg L-1). The monitoring of wastewater heavy metals concentrations (determined on filtrate for both pathway) recorded that the concentration of Fe, Mo, Zn, Cd, Pb, As, Ni, and Mn decreased from (60-100 µg L-1) at point sources to be (5-10 µg L-1) at 1000 m from point sources, however no clear behaviour was recorded for Cu and Co. Moreover the concentrations of all heavy metals by the last sampling point on downstream were remained at 10 µg L-1 or less. The study emphasis that continuous application of industrial wastewater on Riyadh environment will lead to more accumulation of heavy metals in the soil and natural plants, and also high possibilities of groundwater contamination by nitrate.