SummaryAn increasing fraction of energy is generated by intermittent sources such as wind and sun. A straightforward solution to keep the electricity grid reliable is the connection of large-scale electricity storage to this grid. Current battery storage technologies, while providing promising energy and power densities, suffer from a large environmental footprint, safety issues, and technological challenges. In this paper, the acid base flow battery is re-established as an environmental friendly means of storing electricity using electrolyte consisting of NaCl salt. To achieve a high specific energy, we have performed charge and discharge cycles over the entire pH range (0-14) at several current densities. We demonstrate stable performance at high energy density (2.9 Wh L −1 ). Main energy dissipation occurs by unwanted proton and hydroxyl ion transport and leads to low coulombic efficiencies (13%-27%). Although the CGFB has low environmental impact, energy density and power density are too low to be attractive for practical application. KEYWORDSIn this work, we show that the energy density and power density of the CGFB can be improved by implementing a bipolar membrane. The studied system is an energy storage system based on a reversible acid-base reaction. In this system called acid base flow battery (AB-FB), energy is being stored in acid and base solutions created by the bipolar membrane. The charge step of the AB-FB is similar to the well-known bipolar membrane electro dialysis (BPM-ED). BPM-ED converts NaCl solutions into NaOH and HCl solutions by spending electric power to separate protons and hydroxyl ions from water dissociation from the bipolar ----------------------------------------------------This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

The lack of clean water sources, due to the presence of pollutants in water, is a major issue in many countries, including Malaysia. To overcome this problem, various methods have been introduced, including phytoremediation treatment. Therefore, this phytoremediation study examined the ability of five aquatic plants—Centella asiatica, Ipomoea aquatica, Salvinia molesta, Eichhornia crassipes, and Pistia stratiotes—to remove three pollutants—total suspended solids (TSS), ammoniacal nitrogen (NH3-N), and phosphate—from aquaculture wastewater. Using wastewater samples, each containing 50 g of one of the plants, the pollutant levels were measured every two days for 14 days. The results showed a drastic decline in the concentration of pollutants, where C. asiatica was able to remove 98% of NH3-N, 90% of TSS, and 64% of phosphate, while I. aquatica showed the potential to eliminate up to 73% of TSS and NH3-N, and 50% of phosphate. E. crassipes drastically removed 98% of phosphate, 96% of TSS, and 74% of NH3-N, while P. stratiotes was able to eliminate 98% of TSS, 78% of NH3-N, and 89% of phosphate. S. molesta was efficient in removing 89.3% of TSS and 88.6% of phosphate, but only removed 63.9% of NH3-N.

Concerns about the reliability of electricity supplies have motivated researches to investigate the possibility of electrical consumers to take a more active role in the operations of the power system. The work in this paper looks into the potential of an industrial chemical plant to provide support to the electricity grid by means of demand-side response (DR) programs. To do so, this paper proposes a method to assess the flexibility of the plant to provide electrical power reserves while ensuring that the production demand is satisfied, as well as an economic analysis of the plant operations incorporating DR programs to quantify the incentives the plant should receive in order to participate in these programs. Therefore, the current study presents a novel optimization framework which integrates production scheduling with DR programs, with the aim to determine optimal decisions for the operating * corresponding author Email address: d.xenos@imperial.ac.uk (Dionysios P. Xenos) June 7, 2016 conditions within the plant while safely providing services to the electricity grid. Preprint submitted to Applied EnergyKeywords: demand-side management, demand response, optimization, industrial smart grid, power reserve, air separationIndices/Sets ch1 ∈ CH1 measurements of variables of convex hull problem one ch2 ∈ CH2 measurements of variable of convex hull problem two ch3 ∈ CH3 measurements of variable of convex hull problem threee ∈ E products of air separation plant (e.g., N 2 and O 2 )set of headers connected with compressor i J (u) set of headers that are connected to air separation unit u U (z) set of air separation units connected to storage tank z U (e) set of air separation units that produce product e Z (e) set of storage tanks that store product e

Abstract-Efficiency and sustainability considerations have propelled changes in power and process industries. These changes, which include the increased electrification of process industries, are causing concerns about the reliability of future electricity supplies, and therefore motivate the need for a Smart Grid on an industrial scale. This paper presents a method by which process automation engineers can assess the suitability of an oil and gas plant to participate in power system frequency control services. This paper discusses the necessary specifications for an automated system that enables effective variable operation by analysing the safe operating envelope of the plant. To do that, this paper proposes a methodology to characterise the appropriate actuators, variables and limits of set-point change. This methodology is applied to a case study representing an oil processing facility. The resulting analysis indicates demandside response capability that the facility can provide without jeopardising operations on-site.