Cactus Opuntia as natural flocculant for urban wastewater treatment

Abstract

The cactus tree, species Opuntia ficus-indica, is a primary material of many products in various domains such as cosmetics, medicine and nutrition. In the present work, we assess its potential as a flocculant. We tried a technique which adopts three sequential treatments that used coagulation, flocculation and sedimentation processes under certain operating conditions. For this purpose, we used the aluminum sulfate (AS) as coagulant and fresh cladodes juice (FCJ) as bioflocculant. All tests were carried out on high turbid urban wastewater collected from the Metlaoui's Wastewater Treatment Plant (MWTP) (in Gafsa in southwest Tunisia). Experiments with this couple AS/FCJ show very interesting results: a high-removal of turbidity (TUR), suspended solids (SS) and chemical oxygen demand (COD). The percentages of abatement of these parameters are respectively 93.65%, 82.75% and 64.30%. The experimental results of the present study prove that the turbidity, SS and COD removal efficiency of new technique is superior to that of conventional process (with only AS). By this technique, we save 50% in AS dose. Moreover, flocs formed by the treatment using AS/FCJ are coarse and readily settleable.

Extraction and Physicochemical Characterization of Dried Powder Mucilage from Opuntia ficus-indica Cladodes and Aloe Vera Leaves: A Comparative Study

“…They have medicinal attributes such us wound, burn, and ulcer healing, as well as antidiabetic and antiglycation effects [ 3 , 4 ]. Other mucilage applications include its use in foods as a stabilizer, flavoring agent, fat substitute [ 5 ], and edible coating to extend the useful life of fruit [ 6 ], among others [ 7 , 8 ].…”

Toward unfolding the bioeconomy of nopal (Opuntia spp.)

“…Brazil leads the world in terms of hectares (600 000) dedicated to Opuntia cultivation (900 000 ha including cactus plants in the wild), whereas in Mexico the area occupied by Opuntia 's plantations currently is around 230 000 ha . This area is about 150 000 ha in Morocco and 600 000 ha in Tunisia, where scholars have recently shown that cladode juice is even a superior flocculant for urban wastewater treatment …”

The Use of Polymers in the Flotation Treatment of Wastewater

“…To combine the best properties of both types, it was suggested that synthetic PEs be grafted onto the backbone of natural polymers. A completely natural PE has been obtained from the cactus tree (Opuntia ficus-indica) [62,63]. Others have been reviewed [4].…”