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Based on experimental data, a simulation and optimisation of the adsorption Á microfiltration (AMF) process for boron removal from reverse osmosis (RO) permeate was done. An impressively low flow rate of the dry boron adsorbent of about only 54.3 kg h(1 is needed in the adsorbent recirculation loop of a unit for treatment of 100 m3 h(1 of RO permeate and boron concentration in the feed and raffinate 1.2 and 0.4 mg dm(3, respectively. The optimum concentrations of dry adsorbent in the suspension leaving submerged microfiltration module (MF1) and cross-flow microfilters are 110 and 200 kg m(3, respectively. A diafiltration of regenerated adsorbent suspension is an effective way of decreasing of adsorbent flow rate and consumption of chemicals in the desorption loop. Use of about 0.5% of the raffinate for diafiltration is optimal. Specific consumption of regeneration media per unit volume of raffinate at these conditions are 0.97 and 0.19 mol m(3 for acid and alkali, respectively. Segmentation of submerged MF1 module is a useful way of reducing membrane area needed, which is at an optimal conditions in case of ideal mixing in segmented and non-segmented MF1 modules 1315 and 1695 m2, respectively. The overall theoretical power input for MF pumps and air blower is of about 0.018 kWh m(3.

Introduction of the diafiltration of regenerated suspension only very slightly increases the theoretical power inputs for pumps in MF and air blower of aeration in MF1. Air consumption in model unit and theoretical power input to blowers, presented in Table 2, have been calculated for membrane surface area in segmented ideally mixed submerged MF1 modules. In the third segment, the volumetric flow rate of the air per 1 m2 of membrane area was 0.067 Nm3 m(2 h(1. In the first and second segment, 2/3 of this volumetric flow rate was supposed sufficient. The theoretical compression work of blowers has been calculated for ideal isothermal conditions at 258C, assuming that the values of pressure of uncompressed and compressed air are 100 and 140 kPa, respectively. Power input to pumps is about two times higher than to air blower and overall power needed for boron removal in AMF process is of about 0.018 kWh m(3, which is less than in classical IEX installation [2].