Lab-scale Reproduction of Siloxane Foam Synthesis

Evonik has a synthesis reaction to create siloxane-based foam for sale that they run in their Hopewell plant. They would like to utilize a bench scale reactor system for experimentation on the process. The problem is that the foam created on the lab scale does not show the same properties as the foam created on the plant scale and to run experiments accurately they would have to use the plant reactor, wasting both reactor time and plant resources. Evonik wanted the Senior Design team to find a way of recreating the conditions of the plant reactor on the lab scale so that experiments could be run in a way that eliminates waste and gives accurate data. The final direction of the project was to provide a 1 Liter jacketed glass reactor and an outline for a recirculation bath that would mimic the heating profile of the plant reactor as closely as possible, as well as a way to provide a comparable agitation profile to the plant scale. To facilitate the agitation profile, an equation was found to relate the size and speed of both the lab and plant impellers. In addition, a quantitative method of measuring “good” and “bad” quality of the product was discovered in UV-Vis Spectroscopy, which allows Evonik to instantly test the liquid product without having to “foam up” the product and test qualitatively.https://scholarscompass.vcu.edu/capstone/1157/thumbnail.jp

Pilot scale study of chlorination-induced transport property changes of a seawater reverse osmosis membrane

A pilot-scale study was performed to assess variations of reverse osmosis (RO) membrane water permeance (A) and salt retention (Robs) induced by chlorination and to compare them with those observed at the lab-scale. A chlorination protocol was adapted to expose only the surface active layer (an aromatic polyamide)of a composite RO membrane to consecutive free chlorine doses ranging from 40 to 4000 ppm h, at pH 6.9. Along the long-term filtration of seawater, performed with a 4" spiral wound RO module, we monitored the variations of A, the decrease of Robs and the rate of increase of A with time, and found themquantitatively similar to those reported in previous studies performed at the lab-scale under accelerated exposure conditions. The elemental analysis of the feed and permeate streams revealed that the rejection of divalent ions remained constant (ca. 100%), irrespective of the free chlorine dose reached, whereas the rejection of monovalent ions of the seawater (mainly sodium, chloride and bromide ions) decreased as the exposure dose increased. Overall, transposing the characterization procedure to the pilot-scale further supports that chlorination of PA, under pH conditions usually found in desalination plants (6.9 to 8.0), is controlled by the concentration of HOCl, as observed from elemental analysis of the surface by XPS

Carbon capture in the cement industry: technologies, progress, and retrofitting

Several different carbon-capture technologies have been proposed for use in the cement industry. This paper reviews their attributes, the progress that has been made toward their commercialization, and the major challenges facing their retrofitting to existing cement plants. A technology readiness level (TRL) scale for carbon capture in the cement industry is developed. For application at cement plants, partial oxy-fuel combustion, amine scrubbing, and calcium looping are the most developed (TRL 6 being the pilot system demonstrated in relevant environment), followed by direct capture (TRL 4–5 being the component and system validation at lab-scale in a relevant environment) and full oxy-fuel combustion (TRL 4 being the component and system validation at lab-scale in a lab environment). Our review suggests that advancing to TRL 7 (demonstration in plant environment) seems to be a challenge for the industry, representing a major step up from TRL 6. The important attributes that a cement plant must have to be “carbon-capture ready” for each capture technology selection is evaluated. Common requirements are space around the preheater and precalciner section, access to CO2 transport infrastructure, and a retrofittable preheater tower. Evidence from the electricity generation sector suggests that carbon capture readiness is not always cost-effective. The similar durations of cement-plant renovation and capture-plant construction suggests that synchronizing these two actions may save considerable time and money

Enhanced backscatter of optical beams reflected in turbulent air

Optical beams propagating through air acquire phase distortions from turbulent fluctuations in the refractive index. While these distortions are usually deleterious to propagation, beams reflected in a turbulent medium can undergo a local recovery of spatial coherence and intensity enhancement referred to as enhanced backscatter (EBS). Using a combination of lab-scale experiments and simulations, we investigate the EBS of optical beams reflected from corner cubes and rough surfaces, and identify the regimes in which EBS is most distinctly observed.Comment: 10 pages, 8 figure

Testing methodologies for corrosion fatigue

Offshore constructions are subjected to cyclic loading conditions. This situation is combined with the corrosive nature of the surrounding environment. It is of actual concern whether the combined effect is more damaging or not than the superposition of each effect independently. This literature review first introduces the reader to corrosion fatigue. Thereafter a critical comparison of some typical lab-scale fatigue corrosion test setups is given. Special emphasis is devoted to the instrumentation of the setup. This is followed by a design criteria summary which will be used to design a new corrosion fatigue test set-up for evaluating the fatigue properties of steel components in sea water environment

Compressible Media for Water Treatment

Tertiary water treatment is used to remove total suspended solids (TSS) from wastewater. Suez uses compressible media for their tertiary water treatment. There have been supplier issues in the past such as unreliability, long lead-times, unknown manufacturing process, and chances of resale. The chance of resale is an important issue because the specifications may change from one supplier to another. The group was tasked to characterize different types of compressible media for water treatment, design a lab scale filtration unit, and design and manufacture a new media to be tested. In order to gain an operational expenditure advantage, Suez accomplishes media compression without the use of a mechanical device, which was taken into account when designing the filtration unit. The media characterization determined that the media’s fiber was crimped polyethylene terephthalate and the node was atactic polystyrene. The original media was tested on the lab scale filtration unit at concentrations of 10, 30, and 50 mg TSS/L. Due to the size of PVC column diameter (3 inches), channeling and wall-effects were observed, which allowed solids to pass through the media. Because of these effects, the 10 mg TSS/L run was the only acceptable test in terms of turbidity requirements (\u3c2 NTU). New media was designed and manufactured using uncrimped polyethylene terephthalate and hot melt adhesive. The team has future plans to test the new media on the filtration unit. It is expected that the media will be less successful because the fibers are uncrimped.https://scholarscompass.vcu.edu/capstone/1156/thumbnail.jp

Effect of cytostatic drug presence on extracellular polymeric substances formation in municipal wastewater treated by membrane bioreactor

The effect of the cyclophosphamide and its mean metabolites on extracellular polymeric substances (EPS) formation was investigated. Two lab-scale membrane bioreactors were followed in parallel (one with the cytostatic drugs, the second without). Chromatographic and spectroscopic studies (UV–Vis spectroscopy and IR spectroscopy) showed that the presence of CPs induced an increase in EPS concentration in the biological sludge, especially of soluble substances, mainly polysaccharides and proteins. Size exclusion chromatography analysis revealed that in the presence of CPs, macromolecular EPS were formed (polysaccharides corresponding to about 6 KDa and proteins to about 18 KDa). The formation of EPS seemed to be a protection mechanism. More important membrane fouling in reactor with CPs seemed to be related to the retention of an increased amount of soluble substances

Patchouli oil extraction by using hydro distillation (lab scale)

Patchouli or its scientific name Pogostemon cablin, is used in variety of field. For example it is used in Pharmaceutical industry as effective for fungal or bacterial infection and is of great help for insect bite. Patchouli essential oil is mostly used in perfumery industry as product of cosmetic and fragrance oil. The objectives of this research are to study the effect of extraction time and particle size of the leave on the yield of patchouli essential oil. Effects of extraction time and particle size (grinded and non grinded leave) were studied on the yield of patchouli essential oil. The extraction process is performed by using hydro distillation method. Extraction time is varied at 1, 2, 3 and 4 hours and the extraction process is repeated several times on grinded and non grinded patchouli leave. The essential oil obtained, was analyzed by using GC-MS. From the result, the yield of patchouli essential oil is increased as extraction time increased for both grinded and non grinded leave. The highest yield of grinded and non grinded patchouli leave is at four hours in which 1.32% and 0.89% of yield was obtained respectively. From the result also, grinded patchouli leave produces more oil than non grinded patchouli leave

Development of the laboratory anaerobic bioreactor for wet and dry digestion processes

This article presents partial results of the laboratory development of an anaerobic bioreactor designed for the physical modelling of (semi)continuous dry or wet anaerobic digestion processes. A horizontal cylindrical tank reactor of 0.4 m3 total capacity has been developed. The reactor allows the continuous stirring of a liquid batch or the intermittent stirring of a solid batch. The bioreactor has been used as a lab-scale digestor in the research project dealing with high-solids (dry) anaerobic co-digestion organic fraction of mixed municipal solid waste. The first experiment was performed on the mixture of MSW with corn silage (1:1) with the weight of 300 kg