2.2. Operational Details and Parameters

The BWRO membrane is a polyamide thin-film composite TFC-type spiral wound membrane used in the study. In the composition, the RO membrane polyamide (PA) is at the top, followed by polysulfone (PSF) and a base of polyester.

The PA layer is highly susceptible to chlorine exposure and starts degrading at 1000 ppm/h due to the deformation in its structure as Singh explained in 2006. Membrane properties are described in Table 1.

RO membrane specifications and operating conditions.

The recycled RO (R-RO) membrane water recovery %, saltwater rejection %, permeability, and transmembrane TMP are calculated during the operation.

For water recovery percentage following Equation (1) was used [29,30].

where Q_p is permeate and Q_f is feed water flow in (L/h).

Saltwater rejection % was determined using Equation (2) [30].

where C_p refers to permeate and C_f refers to feed concentrations, respectively.