Cesium Removal from Wastewater Using Banana Peel

The potential of banana peel (BP) on the cesium removal from aqueous solutions is study by using different design parameters by adsorption process. The design parameters studied to adsorb cesium using BP as an adsorbent material were initial concentration of cesium , absorbance material packing height which was BP, pH of cesium feed inlet, treatment time, feed flow rate and feed temperature, results show that the higher removal efficiency was 97.50 % for cesium from aquatic solution and this efficiency was decreased with increasing of initial concentration and flow rate while the removal efficiency increased with increasing pH, sorption media bed height and feeding temperature. By this way we can possess different benefits which are: remove the hazard and toxic cesium contaminated the water and get rid of waste BP.

An integrated approach to enhance the desalination process: coupling reverse osmosis process with microbial desalination cells in the UAE

The growing need for better sources of fresh water has led to water desalination become a dominant technology in the water industry, especially in arid countries like the UAE. Across the globe, Reverse Osmosis (RO) has become the key method used to desalinate seawater. Due to the high energy requirements of RO desalination, the need to reduce the energy load has become a pertinent area of research. Microbial Desalination Cells (MDCs) are an emergent technology that show great promise being integrated into the RO desalination process. Studies have shown that a significant portion of the energy utilized in RO desalination could be eliminated by using MDCs as a pretreatment process. In this study, the integration of various MDC types into the pre-treatment process for Reverse Osmosis Desalination were compared and explored. Existing MDC integration setups were briefly explained. Research was split into possible configurations for the integration. This includes optimization of key parameters such as anodic inoculum, feed inlet ratios and accompanying pretreatment processes. The limitations and challenges faced in the integration were investigated and the required future studies aligned with subject was deliberated.

Mathematical modeling and optimization of spiral drum screen in the concrete residue recovery system

To overcome the drawbacks of the traditional concrete residue recovery system, the processing capacity is insufficient and the volume is large. This paper deals with the mathematical modeling and optimization of the spiral drum screen in the concrete residual recycling system. First, based on the maximum amount of material taken by the first spiral at the feed inlet, the paper establishes a theoretical model of screening capacity. Second, according to the relationship between the number of material drops and the screening efficiency, the model of screening efficiency was established from the optimal separation angle of materials. Finally, with the minimum volume of the spiral drum screening sieve as the optimization target, the optimization model was established with the constraints of system screening capacity, screening efficiency, drive power and structural strength. Based on the optimization results, spiral drum screening was produced. The experimental results show that under the condition of 90% screening efficiency, the quality of the spiral drum screen is reduced by 35%, and the screening treatment capacity is doubled, which illustrates the feasibility of the method.

Simulation of CO2 Conversion into Methanol in Fixed-bed Reactors: Comparison of Isothermal and Adiabatic Configurations

CO2 capture and utilization (CCU) has been widely considered as a potential solution to overcome global warming. Conversion of CO2 into methanol is an interesting option to transform waste into value-added chemical while also reducing greenhouse gases emissions in the atmosphere. In this paper, utilization of CO2 into methanol was simulated using Aspen Plus software. The reaction between CO2 and H2 to produce methanol and water was carried out in a simulated fixed-bed reactor with Cu/ZnO/Al2O3 commercial catalyst, following LHHW (Langmuir – Hinshelwood – Hougen – Watson) kinetic model. Isothermal and adiabatic reactor configurations were compared under similar feed conditions and the concentration profile along the reactor was observed. The result showed that isothermal configuration converted 3.23% more CO2 and provided 16.34% higher methanol yield compared to the adiabatic reactor. Feed inlet temperature variation was applied and the effect to methanol production on both configurations was studied. The highest methanol yield for adiabatic and isothermal reactor was obtained at 200 oC and 240 oC respectively.

A Pilot Study of an Electromagnetic Field for Control of Reverse Osmosis Membrane Fouling and Scaling During Brackish Groundwater Desalination

This study investigated the effects of an electromagnetic field (EMF) on control of membrane fouling and scaling during desalination of brackish groundwater using a pilot reverse osmosis (RO) skid. The groundwater was primarily CaSO4 type with a total dissolved solids concentration of 5850 mg/L and hardness of 2500 mg/L as CaCO3. Two EMF devices were installed in the pipeline before a cartridge filter and in the RO feed inlet to induce an electric signal of ±150 kHz to the groundwater. The effects of EMF on membrane scaling were evaluated under accelerated conditions, i.e., without pH adjustment and addition of antiscalant. Two-phase experiments were conducted: Phase 1 (376 h) with the EMF devices turned on after 150 h baseline operation; and Phase 2 (753 h) with the EMF devices turned on from the beginning of testing. The EMF significantly reduced membrane scaling and improved RO performance by 38.3% and 14.3% in terms of normalized water permeability decline rate after 150 h and 370 h operation, respectively. Membrane autopsy results indicated that the fouling layer formed under the influence of EMF was loose with a low density and was easily removed by hydraulic flushing.

Effect of Adding Functionalized Graphene on the Performance of PVDF Membrane in Direct Contact Membrane Distillation

In this paper, the effect of adding modified graphene nanoplatelets (MGNPs) as a filler on the characteristics and performance of Polyvinylidene fluoride (PVDF) membrane in a direct contact membrane distillation (DCMD) configuration was investigated. Both pure PVDF and PVDF/MGNPs composite (2%) membranes were fabricated by using electrospinning technique. The fabricated membranes were characterized using different analyses techniques such as SEM imaging, XRD analysis, static water contact angle as well as membrane porosity and liquid enter pressure measurements. Also, the average fiber diameter and the average membrane pore diameter were estimated using ImageJ software. The prepared PVDF/MGNPs composite membrane exhibited lower fiber diameter by about 5.7%, whereas the contact angle increased by 10 and liquid entry pressure increased by 11.7%. The membrane also showed an enhanced flux that reached about 19.8 kg/m2∙h at feed inlet temperature of 65°C, feed flow rate of 30 l/h. and feed inlet concentration of 10000 ppm. This represents about 13.46% improvement over the pure PVDF membrane at the same conditions. The produced membrane presents a viable alternative to commercial MD membranes.

Treatment of Wastewater Solutions from Anodizing Industry by Membrane Distillation and Membrane Crystallization

The treatment of wastewater containing various metal ions is a challenging issue in the anodizing industry. The current study investigates the application of membrane distillation/crystallization (MD/MCr) for the simultaneous recovery of freshwater and sodium sulfate from wastewater originating from a Danish anodizing industry. MD/MCr experiments were performed on supernatant from wastewater obtained after centrifugation. The effect of various feed temperatures and cross-flow velocities on flux and crystal characteristics was investigated. The crystal growth in the feed tank was monitored through the use of an online PaticleView microscope. The crystals’ morphology and form were determined by using scanning electron microscope (SEM) and X-ray powder diffraction (XRD), respectively, while inductively coupled plasma (ICP) was applied to determine the purity of the obtained crystals. The weight and dimensions of the MD/MCr unit that were required to treat the specific amount of wastewater were evaluated as a function of the feed inlet temperature. It was demonstrated that the application of MCr allows extracting high-purity sodium sulfate crystals and more than 80% freshwater from the wastewater.

Experimental Study of the Hydrocyclone H11 with Rotational Feed

Hydrocyclones are separators that are widely used in industry that belong to an important group of equipments designed to solid-liquid or liquid-liquid separation. The employment of hydrocyclones is generally restricted to an equipment need with a high classifying power (based on the size of particles collected in the underflow) or with a high concentrating capacity. The separation occurs by density difference or particle size distribution of the dispersed phase. In order to maximize the separation efficiency of these devices, the aim of this work was to study experimentally the consequences of an unusual feed in the behavior of a hydrocyclone. Therefore, tests were carried out with aqueous suspensions of phosphate rock at a fixed level of pressure drop equal to 1.47 bar, using the optimized geometry hydrocyclone H11. The influence of the so called rotating feed inlet for the H11 was evaluated in clockwise and anticlockwise. Experimental studies have suggested that the rotation of the fluid in the feed inlet of hydrocyclone did not change significantly the underflow-to-throughput ratio (RL), although it has caused changes in the energy cost and in the performance of the separator.

The Study of Blanking Frequency Effect on the Acceleration Performance of Impact Testing Machine Rotor

This paper designed an impact testing machine to observe the movement characteristics of particles. We simulated the rotor with different blanking frequency and different rotating speed by EDEM to explore the acceleration of the rotor. Through simulation, blanking frequency could have an impact on the rotor acceleration of testing machine, and the greater Blanking frequency was, the more obvious hanging material phenomenon was. Increasing the diameter of feed inlet could ease the phenomenon of hanging material, but would decrease particles speed. Therefore, we should not only avoid the phenomenon of hanging material, but also make the particles get high speed when designing the impact testing machine.