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Syftet med detta examensarbete är att utforska möjligheten att minska resurssvinnet vid utförande av en så kallad clean-in-place-rengöring. Arbetet svarar på frågor gällande de möjligheter som finns att effektivisera rengöringsprocessen alternativt att minska medieförbrukningen genom att förkorta sköljtider. Den huvudsakliga metoden som arbetet baseras på är faktorförsök genom försökplanering. Detta är en metod för att strukturera försök med flera korrelerande faktorer. De faktorer som har förändrats med mål att göra resurseffektiviseringar är en minskning av lutlösningstemperatur för rengöring, prov av olika mängd tillsatsmedel i lutlösningen och en förkortad tid för avslutande kallvattensköljning. Analysen visar att godkända resultat för rengöring erhålls även efter genomförda förändringar. En stor del av arbetet fokuserar på förståelse av systemets uppbyggnad och funktion. Att återvinna spolvatten i högre grad och att använda en lägre lutkoncentration skulle vid vidare arbete kunna ge möjlighet att ytterligare minska resursförbrukningen. / The purpose of this degree project is to explore the possibility of reducing the use of resources in performing a so-called clean-in-place cleaning. The work answers questions about the possibilities that are available to streamline the process or to reduce media consumption by shortening rinse times in the cleaning process. The main method on which the work is based is factor attempts through trial planning. This is a method of structuring trials with several correlating factors. The factors that have been altered, with the goal of making resources use more efficient, are a reduction of the caustic temperature for cleaning, using different amounts of additives in the caustic solution and a shortened time for the last cold water rinse in the cleaning process. The analysis shows that approved results for cleaning are also obtained after changes have been made. A large part of the work has been focused on understanding the system's structure and function. Recycling waste water to a greater extent and using a lower caustic concentration could possibly allow to further reduce resource consumption.

This thesis work is about an improvement in Tate and Lyle’s Clean-in-Place system. The thesis investigates how the designs around two machines can be constructed to automate its Clean-in-Place system. Alongside, two step-by-step manuals were created on how the machines should be cleaned. Furthermore a cleaning agent were searched for which eliminates the oat residues that Tate and Lyle faces. The study’s focus was to reduce the cleaning time in their closed systems by automating the cleaning sequences and use a more suitable cleaning agent for their type of residues.   The background to the study can be described as a cleaning problem. Tate and Lyle’s Clean-in-Place system is operated manually and is executed twice a month. The cleaning agents in their current situation is sodium hydroxide and nitric acid which is not adapted for the remaining residues that appear in their equipment piping and edges. The problem arises when the monument remains isn’t properly cleared so the production cannot be resumed since contamination may occur. The equipment is disassembled, cleaned by hand and reassembled before the production can be continued.   The purpose of the thesis work is to find the most advantageous way to clean a decanter centrifuge and a separator. A more suitable cleaning agent are examined as well as the economic benefits that can occur at reduced cleaning time. The work delimited from practical construction and planning for an upgraded system.   The result consists of two step-by-step manuals that specifically describes how the machines should be cleaned with a Clean-in-Place system. Subsequently, two designs were developed around the decanter centrifuge and separator. The designs describe the placement of pipes, valves and pumps as well as suggestions for new pipelines that provide cleaning benefits. Examination of more customized cleaning was done as an experiment in the chemistry department at the School of Engineering in Jönköping. The experiment presented as unsuccessful and wouldn’t be repeated because of optimistic planning. Instead, the result was presented as a Pugh-matrix where four supplements based on similar studies were used. With an automated system and a qualified cleaning the production time could be increased by 9, 7 %. The economic change was presented as an investment calculation. / <p>Vissa bilagan har valt att döljas på grund av sekretesskäl</p>

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The unwanted occurrence of biofilms in various industries requires critical remedial action in order to prevent their detrimental effects which potentially result in huge economic losses. Adequate monitoring of biofilms is a powerful tool to aid their thorough understanding and ultimate control. The Rotoscope is an instrument based on the principle of light absorption and reflection that was used in this study to monitor and study biofilms. Biofilm development of cocci and bacilli species was monitored using the Rotoscope and microscopy. Light reflectance decreased over time as the biofilm developed. Information on the different stages of biofilm development could also be deduced from light reflectance assays of the Rotoscope. Microscopy validated results which were obtained from light reflectance assays. Information on the morphology of the bacteria, depth of the biofilm as well as the different stages of biofilm development was deduced from EM and CLSM images. The Rotoscope was an easy, effective, on-line monitoring device for the development of biofilms. It was a lso showed to be useful in coll ecting informati on to help characterize bacteria species present within a biofilm The Rotoscope was integrated into a simulated soft drink (SO) production line to monitor biofouling and the efficacy of a clean-in-place (CIP) regime using electrochemically acti vated (ECA) water. During CIF the Catholyte and Anolyte (components of ECA) were effective as detergent and disinfectant respecti vely. This was indi cated by results obtained from microbial analysis of removable slides from the MPD, microscopic analysis, as well as pH, ORP and EC analysis. The absence of microbial growth and soil on microscope slides from the Rotoscope were a good indication of the high efficacy of Catholyte and Anolyte (components of ECA) as detergent and disinfectant respectively in a crp system. In addition, the re latively constant values reported for pH, ORP and EC before and aft er CIP suggests that the Catholyte and Anolyte were effective during CIF. The effect of Anolyte on trihalomethane (THM) formation was observed because of the presence of chl orine compounds. Low levels of THMs were obtained from CIP effluent which provided a good indicati on that Anolyte is an environmentally friendly alternative disinfectant compared to conventional disinfectants currently used in CIP. Increased pH and the presence of bromide resulted in an overall increase of THMs in systems using dissolved organic carbon (DOC) models (Glucose, maltose and phenol). There was however variation in the amount of THM produced using the three DOC models. The differences were attributed to the composition of organic matter in particular the aromacity and the nature and position of the functional groups of the model DOCs. / Dissertation (MSc)--University of Pretoria, 2012. / Microbiology and Plant Pathology / unrestricted

<p> Fouling is one of the main problems in the food processing industry. The formation of fouling generates complications that could significantly impact the cost of production due to a reduction in heat transfer capacity or sanitation problems. Fouling formation inside enclosed systems can also lead to the growth of biofilms, causing food safety hazards. The fouling layers are firmly attached to the food contact surface of the equipment in ultra-high temperature (UHT) systems where a food product gets sterilized. Clean in place (CIP) is the most common process for cleaning and removal of fouling as it reduces cleaning time, chemicals, and water consumption compared to a regular cleaning out of place process. While cleaning and solids removal, microbubbles (MB) have shown improvement by enhancing the interaction of the components in the cleaning process with the source of contamination. Therefore, a novel pilot-scale microbubble-based CIP (MBCIP) technology was used for cleaning of fouled surfaces and compared to the traditional CIP process in terms of efficiency and reduction in water usage. The fouling layers attached to the food contact surface of the equipment in UHT was the main area examined. The research evaluated the fouling created at 110ºC in sections of stainless-steel pipes heated in a convection oven and at 121 ºC during regular processing in a UHT with coil heat exchangers system. Reconstituted Non-fat Dry Milk Powder (NFDM) was used as the primary source of protein to evaluate the cleaning efficiency. CIP factors were combined with temperatures at 21.11 ºC, 43.33 ºC, and 76.66 ºC, together with water, alkali, and acid, respectively. The optimal conditions for MBCIP were established and applied to a pilot-scale UHT system representative of a commercial-scale UHT system. The sequence of the CIP was water, alkali, water, acid, and water. The results showed that the acid solution at 76.66 ºC with microbubbles had a significantly higher protein removal compared to the rest of the evaluated conditions, removing 72% of the initial protein content compared to alkali and water which were 10 and <2.55%, respectively during 60 minute of CIP. During the full CIP with the combination of water, alkali, and acid, the effect of alkali was significantly higher than in the rest of the steps performed individually. With the addition of MB overall, CIP removed a considerable amount of protein (>21.5%) in a UHT system compared to the traditional CIP method within the 60 minutes period. CIP chemicals were the main factor contributing to the protein removal, and the gas content was the second most crucial factor in determining the removal. The addition of MB will have a meaningful impact when interacting with cleaning chemicals for industrial CIP. MB also occupies a very small amount of space inside the pipelines representing <0.05% of the volume fraction of the fluid inside the pipes, nevertheless, it can potentially reduce water consumption and provides a sustainable cleaning method for the food industry </p>

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No description available.

Komati Power Station has installed a membrane plant consisting of ultrafiltration, double pass reverse osmosis and continuous electro-deionisation to treat cooling tower blowdowns in order to produce demineralised water and to conduct sidestream chemistry control of the cooling water circuit. This plant has replaced the existing ion-exchange plant that was used for the production of demineralised water and thus serves to reduce the loading of mobile salts in the ash dam (90% reduction) by eliminating regeneration effluent from the ion-exchange plant. Due to oil contamination in the cooling water circuit (when oil from oil coolers leaks into the cooling water), the membrane plant was also designed to operate on raw water from either the Nooigdedacht or the Vygeboom Dam or a blend of both dams. This is considered to be an emergency intervention under abnormal conditions to prevent possible irreversible fouling of the membranes due to oil in the cooling water. The Nooigtedach Dam water contains high concentrations of organic matter and is also enriched with nutrients due to raw sewage influent into the Dam water. This poses a challenge with regard to treatment of the high fouling feed water on the membrane plant. Natural organic matter in water has the ability to foul reverse osmosis membranes. This adversely affects the operation of the reverse osmosis process. However, very little information is available regarding the fouling characteristics of natural organic material in the raw and cooling water at Komati Power Station for the reverse osmosis membranes. Therefore, a pilot study was undertaken to determine the influence of natural organic matter on membrane fouling, to optimise the process for the removal of natural organic matter and to assess the ability of two different reverse osmosis membranes to effectively treat the high fouling feed water at Komati Power Station. The ability of a polyethersulphone hollow-fibre ultrafiltration membrane system was first evaluated to remove natural organic matter in the feedwater, by conducting pilot tests, initially without coagulation of the raw water and thereafter with in-line coagulation for organics removal. Jar tests were conducted in the laboratory to determine the most suitable coagulant and dosage for turbidity and natural organic matter removal. Various coagulants were tested and, based on the results of the jar tests, a coagulant (U3000) was identified based on optimal removal of both total organic carbon and turbidity at a dosing level of 20 mg/L. During the operation of the ultrafiltration pilot plant, permeate flow; feed pressure and feed temperature were monitored. Performance of the ultrafiltration membrane was monitored in terms of flux versus time for operation with and without a coagulation process. The results indicated that there was very little total organic carbon removal (maximum removal of 4%) without coagulation and a slight decrease in flux. The flux declined as a result of fouling but could be recovered by performing hydraulic backwashes and CEB procedures. Permeate flux, however, could be maintained at about 90 Lmh (from 642 hours of operation). Since most of the organics passed through the ultrafiltration membrane, it was concluded that the loss in flux was due to colloidal fouling of the membrane. This was observed when the operation was carried out using raw water as feed as well as when cooling water was used. The total organic carbon removal increased to 30% when the plant was operated with inline coagulation. The flux remained relatively stable during the first 600 hours of operation and only decreased significantly during the last 200 hours of operation as a result of fouling. The reduction in flux prior to cleaning was less than the 15% (maximum flux decline of 9.9% during the test period) which is acceptable according to the industry norm of 15%. It appeared that flux could be maintained at around 90 Lmh which was about the same as when no coagulant was applied. The 30% total organic carbon reduction that was obtained was not sufficient to reduce the organics to the level of 6mg/L dissolved organic carbon that was specified by the membrane manufacturer for the standard brackish water reverse osmosis membrane. Two reverse osmosis membranes – the standard brackish water reverse osmosis membrane (BW30-2540) and the extra-low-fouling membrane (BW30XFR-2540) – were assessed in terms of their ability to remove dissolved organic carbon, ease of cleaning of the membrane and the ability to recover flux after cleaning. This was done to establish which membrane is more suited to Komati’s high-fouling feedwater. The evaluation of the performance of the two reverse osmosis membranes was conducted using pre-treated water (filtered water after in-line coagulation, anti-scalant and biocide dosing) as well as using water that was not pre-treated. During operation (under both conditions), the normalised permeate flux, conductivity, dissolved organic carbon and organics absorbing at UV254 were monitored. It was established that in terms of flux decline that the extra low-fouling membrane gave slightly superior performance to that of the standard membrane, achieving longer production runs (up to 5 days compared with 3 days achieved by the standard brackish water membrane) without requiring chemical cleaning. The low fouling membrane achieved better CWF recovery after the cleaning cycles (81.26% Lmh of the virgin membrane on the occasions when there was flux loss) compared to the standard membrane (restored to 77.35% of CWF of the virgin membrane) when using untreated feed water. This performance improved when pre-treated feed water was used and the low fouling membrane’s CWF regained after the CIP was 95.89% which was within the industry norm of a flux recovery of 95%, indicating that the CIP had been effective. It was determined that the TOC rejection of the low-fouling membrane was higher (average TOC rejection of 97%, maximum TOC rejection of 99%) than that of the standard membrane (average TOC rejection of 95.3%, maximum TOC rejection of 97%). Preliminary efforts to optimize the pre-treatment for organics removal in order to reduce organic loading for the RO membranes confirmed that the use of granular activated carbon and use of an organic scavenger resin might not be economically feasible due to the relatively quick TOC breakthrough (8910BV, approximately 18000BV and less than 18000BV for the Filtrasorb 300, Filtrasorb 400 and organic scavenger resin, respectively). Although further investigations should still be conducted, the preliminary results indicate that it would be beneficial to also identify other options that can be further investigated for optimization of organics removal at Komati Power Station. Decline in the normalised flux as well as the evidence of biofouling were witnessed during the pilot operation suggesting that the membranes were fouled. Autopsies were performed on both membranes to identify foulants responsible for the decline in flux that was observed during the pilot study. The results did not indicate an organic foulant on the membrane surface. Biofouling should however, be monitored in the main plant as this was suspected to have resulted in the flux decline during the pilot study. The low fouling membrane demonstrated a better capability to treat the Komati raw and cooling water and would be expected to achieve lower operating costs for the plant (CIP costs and membrane replacement costs) while achieving better organics removal and it is therefore recommended that the low-fouling membranes be used at Komati Power Station as they are superior to the standard membrane and the cost of the low-fouling membranes is comparable to that of the standard membrane. While this would provide somewhat better performance than that obtained with the standard brackish water membranes, it is proposed that further investigation into pre-treatment optimization for organics removal as well as more efficient cleaning solutions be investigated to improve the performance and economics of the main water treatment plant at Komati power Station. / Dissertation (MSc)--University of Pretoria, 2013. / gm2014 / Chemical Engineering / unrestricted

<p dir="ltr">Pea protein is one of the most used plant proteins in food products, acting as an alternative to conventional animal protein sources due to its abundant, nutritious, and ease in supply chain characteristics. The objective of this study was to investigate the impact of homogenization and UHT processing parameters on the properties of protein emulsion. Protein emulsions (8% w/w pea protein isolate and 1% w/w sunflower oil) were freshly prepared prior to processing, and the untreated sample was considered as the control (NT). The pilot-scale aseptic processing system (APS) used in this study consisted of two coil-in-shell heaters and two coolers. Samples flowed through each section of the APS system following this order: balance tank, pre-heater, final heater, hold tube, pre-cooler, and final cooler. The homogenizer was located either after the pre-cooler (AC) or the pre-heater (AH) with a controlled temperature of 165F. A third setup was utilized by bypassing the homogenizer in the UHT system. An additional 8-hour continuous run was conducted to mimic a commercial manufacturing operation by recirculating the protein emulsion in the UHT system, and fouling detections were made using a non-intrusive sensor (NICS). 5% w/w soy protein, 1% w/w sunflower oil oil-in-water emulsion was also used for fouling tests. Protein concentration, pH and zeta potential, Cryo-SEM microscopic image, particle size distribution, flocculation index (FI), coalescence index (CI), viscosity and color data were collected and analyzed. The protein concentration had a 23.20 ± 4.00 %, 28.35 ± 5.02 %, 27.98 ± 5.05% and 21.38 ± 5.75% reduction for AC, AH, UHT and NT samples, respectively, when compared with the initial concentration in the formula. AC, AH, UHT and NT samples had pH values of 7.24 ± 0.01, 7.27 ± 0.01, 7.28 ± 0.02, 7.41 ± 0.01, and zeta potential values of -42.91 ± 0.89, -47.30 ± 0.91, -46.91 ± 1.40 and -50.11 ± 1.47 mV. AC sample had a smaller and NT sample had a bigger, respectively, mean weighted size D 4,3 value than AH and UHT samples, which could also be seen in Cryo-SEM images where only AC images contained more visually observable smaller particles. FI and CI for AC, AH and UHT indicated the formation of flocs but no irreversible aggregations were found. Shear-thinning AC, AH, UHT and NT samples had viscosity decreases from 4.00 to 3.56, 3.88 to 3.75, 4.02 to 3.79 and 10.42 to 9.56 mPa*s in 1 1/s to 100 1/s shear rate range. NT sample had a very noticeable color difference from the other three treated samples. Overall, AC samples had similar or better emulsion stability in all aspects than AH and UHT samples, suggesting that AC processing could potentially be used in the protein beverage industry for manufacturing products with improved shelf stability. Severe foulants buildups were neither observed nor detected by a non-intrusive continuous sensor (NICS) in the UHT system within 8 hours of process for both pea protein and soy protein emulsion, indicating that this UHT-homogenization processing can potentially be adapted to current industrial practices for higher-quality protein beverages.</p>