Yes / The estimation of Polycrystalline Diamond Compact (PDC) cutters wear has been an area of concern for the drilling industry for years now. The cutter's wear has been measured practically by pulling the bit out for evaluation at the surface. It is important to find the right time for tripping out as this helps to avoid the fishing job and reduces the operational cost significantly. The prediction of the drilling performance is based on the interaction of cutter and rock. Several authors focused on the cutter-rock interface but only a few researchers tried to model the wear of the PDC bit cutters. The aim of this research is to understand the relationships between the rate of penetration (ROP) and the drilling variables per each foot, and then determine the overall bit efficiency for the whole drilling operation. A new mathematical model is derived to predict the PDC bit performance by considering the factors that were already not taken into account. These factors include rock strength, bit design, and bit hydraulic. The model investigates the effect of these parameters to estimate the abrasive cutters wear on the inner and the outer bit cones by deriving modified equations to calculate the mechanical specific energy (MSE), torque, and depth of cut (DOC) as a function of effective blades (EB). The model is used to forecast the bit cutters wear conditions in four wells in the oil fields located in Libya, which were drilled with three different PDC's sizes. The model enables the results to be compared to the actual bit cutters wear measured for inner and outer cones. The results are found that are well in agreement with the actual field data obtained in bit records. / Financial support from ministry of higher education in Libya.

Yes / Predicting the PDC bit performance during drilling operation is important for the cost effectiveness of the operation. The majority of PDC bits are assessed based on their performance that are relative to offset wells. Determination of mechanical specific energy (MSE) in real time and compare it with the known MSE for a sharp bit to assess the bit life has been utilized by several operators in the past. However, MSE still cannot be used to predict the bit performance in exploration wells and also it cannot assess the bit efficiency in the inner and outer cones. A more precise approach needs to be devised and applied to improve the prediction of bit life and the decision when to pull the bit out of the hole. Effective mechanical specific energy (EMSE) developed in this work is a new wear and performance predictive model that is to measure the cutting efficiency based on number of cutters, which contact the rock as a function of weight on bit (WOB), rotary speed (RPM), torque, and depth of cut (DOC). This model modifies the previous MSE model by incorporating such parameters and including detailed design of the bit, number of blades, cutter density, cutter size, and cutting angle. Using this approach together with the analysis of rock hardness, a level of understanding of how the drilling variables influence the bit performance in the inner and outer cone is improved, and a convenient comparison of the bit condition in the frame of the standard bit record is achieved. This work presents a new simple model to predict the PDC cutters wear using actual data from three sections drilled in three oil wells in Libya. It is found that the obtained results are in well agreement with the actual dull grading shown in the bit record.

Yes / Brackish water can be considered an important source of fresh water, via desalination, especially for arid districts. Reverse Osmosis (RO) process has been successfully used to produce fresh water from brackish water sources. However, there is still the challenge of improving the performance of multistage RO desalination plants. From the selection of the RO configurations to the selection of the appropriate type of membranes and the operating conditions at the end determines the performance of RO process in terms of recovery, salt rejection, energy consumptions and ultimately the cost of production of freshwater. Using model-based simulation, this work attempts to investigate the most suitable types of membranes for an industrial scale RO plant from a set of different membrane brands that would attain the highest-performance at lowest specific energy consumption (SEC). As a case study, we considered a multistage multi-pass medium-scale RO plant (1200 m3/day) of Arab Potash Company (APC, Jordan) which produces high quality water for the boilers after pre-treatment stage. The simulation results confirmed that employment of the Filmtec BW30LE-440 would increase water recovery by about 22% besides reducing the product salinity and SEC by about 15% and 10%, respectively compared to the existing membrane.

Yes / Polymer extrusion is an important but an energy intensive method of processing polymeric materials. The rapid increase in demand of polymeric products has forced manufactures to rethink their processing efficiencies to manufacture good quality products with low-unit-cost. Here, analyzing the operational conditions has become a key strategy to achieve both energy and thermal efficiencies simultaneously. This study aims to explore the effects of polymers' rheology on the energy consumption and melt thermal quality (ie, a thermally homogeneous melt flow in both radial and axil directions) of extruders. Six commodity grades of polymers (LDPE, LLDPE, PP, PET, PS, and PMMA) were processed at different conditions in two types of continuous screw extruders. Total power, motor power, and melt temperature profiles were analyzed in an industrial scale single-screw extruder. Moreover, the active power (AP), mass throughput, torque, and power factor were measured in a laboratory scale twin-screw extruder. The results confirmed that the specific energy consumption for both single and twin screw extruders tends to decrease with the processing speed. However, this action deteriorates the thermal stability of the melt regardless the nature of the polymer. Rheological characterization results showed that the viscosity of LDPE and PS exhibited a normal shear thinning behavior. However, PMMA presented a shear thickening behavior at moderate-to-high shear rates, indicating the possible formation of entanglements. Overall, the findings of this work confirm that the materials' rheology has an appreciable correlation with the energy consumption in polymer extrusion and also most of the findings are in agreement with the previously reported investigations. Therefore, further research should be useful for identifying possible correlations between key process parameters and hence to further understand the processing behavior for wide range of machines, polymers, and operating conditions.

Yes / In this work, we considered model-based simulation and optimisation of a medium scale brackish water desalination process. The mathematical model is validated using actual multistage RO plant data of Al- Hashemite University (Jordan). Using the validated model, the sensitivity of different operating parameters such as pump pressure, brackish water flow rate and seasonal water temperature (covering the whole year) on the performance indicators such as productivity, product salinity and specific energy consumption of the process is conducted. For a given feed flow rate and pump pressure, winter season produces less freshwater that in summer in line with the assumption that winter water demand is less than that in summer. With the soaring energy prices globally, any opportunity for the reduction of energy is not only desirable from the economic point of view but is an absolute necessity to meet the net zero carbon emission pledge by many nations, as globally most desalination plants use fossil fuel as the main source of energy. Therefore, the second part of this paper attempts to minimise the specific energy consumption of the RO system using model-based optimisation technique. The study resulted not only 19 % reduction in specific energy but also 4.46 % increase in productivity in a particular season of the year. For fixed product demand, this opens the opportunity for scheduling cleaning and maintenance of the RO process without having to consider full system shutdown.

The laboratory cutting specific energy is widely used to estimate the cuttability of rocks by a roadheader fitted with sharp picks. Sharp picks on the other hand become blunt due to wear in time and require replacement. Although it is known that the pick blunting affects adversely the rock cuttability, no study exists to show the relationships between the degree of pick wear and the cutting specific energy obtained by standard cutting tests. In this study, standard cutting tests were carried out on different rock types, with picks having varying degrees of blunting. The relationships between wear flats and the cutting forces, specific energies and size distribution for various rock properties such as uniaxial compressive strength, tensile strength, cone indenter number, shore hardness, schmidth hammer hardness, density and grain size were established. The mean cutting force and the cutting specific energy have been found to increase 2-3 times and 4-5 times respectively with 4 mm wear flat as compared to sharp picks as the strength and density of rocks increase. No relation exists between mineral grain size and the cutting performance. A definite relation could not be established between the wear land and the size distribution of the product. Charts have been produced to predict critical wear flats for different rock property values considering 25 MJ/m&sup3 / as the limiting specific energy above which poor cutting performance occurs. Nine prediction models have been developed by statistical analysis to estimate the laboratory cutting specific energy from various rock properties and wear rates.

In this thesis, in-situ instantaneous cutting rates of boom type, medium-weight milling type roadheaders (Mk-2B) at &Ccedil / ayirhan Coal Mine are determined by studying previous performance tests and carrying out additional underground cutting tests. Some rock properties such as uniaxial compressive strength, tensile strength, Cone Indenter hardness, Shore hardness, Schmidt hammer rebound hardness and laboratory cutting specific energies are determined by laboratory tests for the rock and coal types encountered in the drivage of roadways. The relations between the instantaneous cutting rates and the above rock characteristics and the laboratory cutting specific energies are established. The results show that instantaneous cutting rates can be best predicted using laboratory cutting specific energy which provides the highest correlation (R2 = 0.8411) as compared to other rock properties. The model developed for the medium-weight machine to predict instantaneous cutting rate is compared with those developed earlier for the light-weight and heavy-weight machines. It is determined that improvements in cutting performance with the medium-weight machines as compared to light-weight machines is achieved for the rocks requiring laboratory cutting specific energy greater than 5 MJ/m3.

Syftet med det här examenarbetet har varit att analysera ett flerbostadshus som redan har energieffektiviserats med vanliga energieffektiviseringsåtgärder för att ytterligare installera andra energiåtgärder som är lönsamma och kan minska den inköpta energin.Bygg- och fastighetssektorns står för ungefär 40% av energianvändningen i Sverige. En stor del av denna energianvändning går det att minska genom att utföra energieffektiviseringsåtgärder på befintliga byggnader. Sverige har ett miljömål som är att nå ett nettoutsläpp år 2045 och bostadssektorn har en stor potential för att underlätta att Sverige når sitt energimål. Vanliga energieffektiviseringsåtgärder i flerbostadshus är bland annat fasad- och vindisolering, fönsterbyte och att installera mer energieffektiva ventilationssystem och belysningar. Exempelhuset har redan fått vindisolering, fasadputsning, treglasfönster, energieffektiva LED-lampor och en ny undercentral. Detta har resulterat i en specifik energianvändning som låg på ca 108 kWh/m2 år 2020. I Sverige ligger den genomsnittliga specifika energianvändningen på flerbostadshus ca 134 kWh/m2. För att få ner den specifika energianvändningen ännu mer har fyra andra energieffektiviseringsåtgärder undersökts och analyserats med avseende på sina energibesparingspotentialer och lönsamheter. De valda åtgärderna är en solvärmeanläggning, en solcellanläggning, snålspolande armaturer och en spillvattenvärmeväxlare (Ekoflow). Den specifika energianvändningen har gått ner till 90 kWh/m2 efter dessa energibesparingsåtgärder har utförts. Det visade sig att de snålspolande armaturerna, solcellanläggningen och solvärmeanläggningen är lönsamma. Däremot visade resultatet att spillvärmeväxlaren (Ekoflow) inte är lönsam. Men genom att paketera alla åtgärder har det lyckats att uppfylla lönsamhetskravet och att få en gemensam internränta som är högre än kalkylräntan. Kalkylräntan antas vara 5 % och internräntan har beräknats 6,45 %.Lönsamheten är förstås beroende på framtida energipriser såsom fjärrvärme-och elpriser. På energimarknaden kostar en kWh el ca 1,82 kr och en kWh värme ca 0,847 kr för konsumenter. Med hjälp av annuitetskalkyl har kostnaden för en kWh som alstras genom solvärmeanläggning och solcellanläggningen beräknats. För solvärme kostar 0,75 kr/kWh och för solel kostar 1 kr/kWh. Detta är fast pris under 30 år, alltså under kalkyltiden och denna energi är billigare jämfört med energin på marknaden. / The purpose of this thesis was to analyse an apartment building that has already been implemented with standard energy efficiency measures to further install other energy efficiency measures that are profitable and can reduce the purchased energy.The building sector is responsible for about 40 percent of energy use in Sweden. A large part of this energy use can be reduced by installing energy efficiency measures on existing buildings. Sweden has an environmental goal which is to reach a net emission by 2045 and the building sector has great potential to facilitate for Sweden to reach its energy goal.Common energy efficiency measures for multi-family buildings include insulation of external walls and attic insulation, window replacement, installing more energy-efficient ventilation systems and upgrading the lighting system. The example house has already received an attic insulation, facade plastering, triple-glazed windows, energy-efficient LED lamps and a district heating substation. This has resulted in a specific energy use that was 108 kWh / m2 in 2020 and in Sweden the average specific energy use is 134 kWh / m2 in apartment buildings.To reduce more the specific energy use, 4 energy efficiency measures have been investigated to be able to assess their potential of energy use reduction and profitability. These measures are a solar heating system, a photovoltaic system, Energy-efficient taps, and a wastewater heat exchanger (Ekoflow). The specific energy consumption has decreased to 90 kWh / m2 after these energy saving measures have been implemented. It turned out that the Energy-efficient taps, the photovoltaic system, and the solar heating system are profitable and Ekoflow is not profitable. But by collecting all measures in a package, it has been succeeded to fulfil the profitability requirement and to obtain a common internal rate of return which is higher than the discount rate. The discount rate is assumed to be 5% and the internal rate of return has been calculated at 6.45%.Profitability is dependent on future energy prices such as district heating and electricity prices. The market price is one kWh of electricity about 1.82 SEK and one kWh of heat costs about 0.847 SEK. Using an annuity calculation, the cost for a kWh obtained through a solar heating system and the solar cell system has been calculated. For the solar collector is calculated 0.75 SEK / kWh, and for the photo voltaic become 1 SEK / kWh. It will be a fixed price during the calculation period which is 30 years, and that means that this energy is cheaper than the energy on the market.

This master’s thesis deals with side channel pumps. Derivated formula of specific energy is supplemented by other equations and the results of CFD simulation. Further are analysed the mechanism of energy transfer from the impeller and external characteristics of the pump.

As the world becomes more focused on sustainability, there is increasing pressure on steel-bearing companies to improve their energy efficiency and reduce their carbon footprint. The heat treatment process accounts for about 25% of SKF's energy consumption, and it aims to achieve decarbonized operations by 2030 and the supply chain by 2050. Therefore, improving the energy efficiency of the heat treatment process can have significant economic and environmental benefits for the company. This thesis project aimed to conduct an energy mapping of different heat treatment processes at SKF to develop a methodology and standard key performance indicator for establishing energy performance and ensuring comparability between installations and processes. Three heat treatment processes were studied: through hardening, location A; case carburizing, location B; and surface induction hardening, location C. A detailed methodology and guidelines for carrying out energy mapping were developed. A standard key performance indicator known as Specific Energy consumption in kWh/kg at a particular utilization in % was set for comparisons among different heat treatment processes. Regression analysis was used to normalize the results. On the same utilization level, case carburizing, location B consumes more energy than through hardening, location A. Surface induction hardening, location C consumes 90% less than others and is less dependent on utilization. The carbon intensity in g CO2-eq/kg for greenhouse gas scopes 1, 2 and 3 were also studied. Case carburizing, location B had the highest climate impact due to the coal-based electricity mix of the country. Hence, the future availability of renewable electricity is critical when switching from gas to electricity across factories in SKF.