Membranes and renewable energy — a new era of sustainable development for developing countries

This article outlines the combination of a small scale hybrid ultrafiltration and nanofiltration/reverse osmosis system with solar energy. The system is targeted to remote communities with access to either contaminated surface or brackish water. The treatment accomplishes dual barrier disinfection, desalination, and removal of trace contaminants such as arsenic. Investigation of the system is carried out for a variable power source that leads to fluctuations in feed flow and recovery. Those variations may affect water quality and fouling and to ensure satisfactory performance in locations far from qualified maintenance personnel this information needs to be integrated into process design and operation procedures. The system exhibits a very low specific energy consumption and is able to desalinate brackish water to drinking water guidelines. Trace contaminant removal is under investigation and results are not presented in this paper

Renewable Energy Powered Membrane Technology. 1. Development and Characterization of a Photovoltaic Hybrid Membrane System

In isolated communities where potable water sources as well as energy grids are limited or nonexistent, treating brackish groundwater aquifers with small-scale desalination systems can be a viable alternative to existing water infrastructures. Given the unavailability of power in many such situations, renewable energy is an obvious solution to power such systems. However, renewable energy is an intermittent power supply and with regards to the performance of intermittently operated desalination systems, only very limited experience exists, both with regards to efficiency as well as water quality. In this paper, this lack of knowledge is addressed by evaluating a system operated with varying parameters (pressure and flow) with constant power as a step toward defining a safe operating window, and they provide a basis for interpreting future data obtained with a renewable energy source. Field trials were performed on a brackish (5300 mg/L TDS; 8290 μS/cm) bore in Central Australia with a photovoltaic-powered membrane filtration (PV-membrane) system. Four nanofiltration and reverse osmosis membranes (BW30, ESPA4, NF90, TFC−S) and a number of operation parameter combinations (transmembrane pressure, feed flow, TFC-S) and operating parameters transmembrane pressure and feed flow were investigated to find the best operating conditions for maximum drinking water production and minimum specific energy consumption (SEC). The ESPA4 membrane performed best for this brackish source, producing 250 L/h of excellent drinking water (257 mg/L TDS; 400 μS/cm) at an SEC of 1.2 kWh/m3. The issue of brine disposal or reuse is also discussed and the article compares the salinity of the produced brine with livestock water. Since the feedwater is disinfected physically using ultrafiltration (UF), the brine is free from bacteria and most viruses and hence can be seen more as a reusable product stream than a waste stream with a disposal problem

Simultaneous nitrification/denitrification and trace organic contaminant (TrOC) removal by an anoxic-aerobic membrane bioreactor (MBR)

Simultaneous nitrification/denitrification and trace organic contaminant (TrOC) removal during wastewater treatment by an integrated anoxic-aerobic MBR was examined. A set of 30 compounds was selected to represent TrOCs that occur ubiquitously in domestic wastewater. The system achieved over 95% total organic carbon (TOC) and over 80% total nitrogen (TN) removal. In addition, 21 of the 30 TrOCs investigated here were removed by over 90%. Low oxidation reduction potential (i.e., anoxic/anaerobic) regimes were conducive to moderate to high (50% to 90%) removal of nine TrOCs. These included four pharmaceuticals and personal care products (primidone, metronidazole, triclosan, and amitriptyline), one steroid hormone (17β-estradiol-17-acetate), one industrial chemical (4-tert-octylphenol) and all three selected UV filters (benzophenone, oxybenzone, and octocrylene). Internal recirculation between the anoxic and aerobic bioreactors was essential for anoxic removal of remaining TrOCs. A major role of the aerobic MBR for TOC, TN, and TrOC removal was observed

Repercussions del codi i el programari en la nostra vida diària

Al llarg d'aquesta conversa amb Andreas Broeckmann, el codi i el programari artístic esdevenen els temes principals. Fem un repàs del passat, el present i el futur de l'art digital, i més específicament del programari i el codi artístics. En aquest repàs també parlem de l'evolució de les utopies de l'art digital, les que ja s'han ensorrat i les que estan sorgint, i també parlem de la repercussió de l'evolució de les utopies i de la creació de programari i codi en la nostra cultura i societat. Vull veure el vídeo de l'entrevista [YouTube - 33 min