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In this work, a non-conventional distillation sequence with thermal coupling (Petlyuk Column) was presented as a technique to perform the separation of the NGL consist of ethane, propane, butane or other higher alkanes. The improvements were investigated through the energy analysis and remixing effect. From the result obtained, it was found that the Petlyuk arrangement consumes less amount of energy and able to reduce the remixing effects as compared to the conventional column sequencing. The Petlyuk arrangement saved about 44.49% and 12.83% in terms of cooling and heating duty, respectively. The overall annual energy saving shown by this arrangement is 39.22%. This arrangement proved to be able to prevent the remixing effect occurrence that contributes to thermal and separation inefficiency. The desired separation efficiency also obtained by this arrangement as all the product specifications are met. The ability in avoiding remixing effect by the Petlyuk column permits a significant reduction in CO2 emission with an average of 29.43 % of each equipment involved. Hence, it can be concluded that the Petlyuk arrangement model is a better alternative to be implemented in the NGL fractionation train.

The characterization and properties of sand from beaches in Malaysia that has potential to be used as proppant in hydraulic fracturing was investigated through impingement tests. Eight sand samples were obtained from eight different locations in Malaysia; three samples from West Coastal beaches (Selangor) and five from East Coastal beaches (Kelantan). These impingement tests were conducted by varying several parameters i.e. size ranges of sand, type of targeted metal and distance of nozzle standoff from target. In these tests, air was fed through an acrylic pipe with inner diameter of 8 mm and 4 m length at gas velocity of 100 m/s and flow rate of 200 l/min. 250 g of sand samples were fed in compressed air stream and the samples were projected toward targeted metal i.e. mild steel and aluminium with a 90° of impingement angle. These tests were conducted at different separation distance of 0.5, 2.5 and 5.0 inches of nozzle and target. The results were analysed by measuring the mass loss of the metals after impingement and the images of the impinged metals were captured using camera. The highest metal loss was obtained when the targeted metal was impacted with the largest size range of sand samples. The mass loss of mild steel ranged from 0.03 to 0.16 g and 0.10 to 0.22 g for aluminium, at a variable distance between the nozzle and metal target due to higher hardness of mild steel than aluminium. The mass loss reduced when the distance between nozzle and metal target increased due to energy loss because of the inter particle collision.

Alkaline-surfactant-polymer (ASP) flooding is significant to the oil and gas industry due to synergistic interaction between alkaline, surfactant and polymer. However, chemical losses due to adsorptions of surfactant and polymer on the rock surface could lead to inefficiency of the process. There are also significant uncertainties on adsorption mechanism when surfactant is flooded with presence of alkaline and polymer. This study highlights the static adsorption tests using anionic sodium dodecyl sulphate (SDS), hydrolysed polyacrylamide (HPAM) and sodium carbonate (Na2CO3) as the surfactant, polymer and alkaline, respectively. Sand particles and kaolinite clay were used as the reservoir minerals. The adsorption tests were conducted at various surfactant concentrations ranging from 50 to 2000 ppm. Sodium chloride (NaCl) concentration was investigated from 0 to 2 wt.%, while the local sand and kaolinite was mixed in surfactant solution at a fixed mass to volume ratio of 1:5. The static adsorption test was conducted by shaking the mixture samples and centrifugation before analysing the supernatant liquid using UV-Visible spectrophotometer. The results showed that the surfactant adsorption was higher on kaolinite compared to sand particle. The higher the salinity, the higher the adsorption of surfactant due to higher ionic strength. The adsorption of SDS surfactant on sand particles and kaolinite was lesser in ASP system compared to the presence of surfactant solution alone. Thus, it can be concluded that the presence of polymer and alkaline in ASP solution have great potential to reduce the surfactant adsorption on both sand particle and kaolinite.

Mercaptans is one of the major volatile organosulfur compounds produced in natural environments. The presence of mercaptans creates a great threat to the environmental safety and can cause health problems due to their toxicity, even at low concentrations. Knowledge on the thermodynamics properties and vapor-liquid equilibria of mercaptans-water is important for environmental impact studies and engineering design particularly when dilute aqueous systems are involved. In this work, we propose a generalized thermodynamic framework that uses Soave, Redlich and Kwong (SRK) EOS/Peng-Robinson (PR) EOS coupled with Huron-Vidal mixing rules to correlate the solubility of mercaptans-in water systems at low concentration. For this approach, the Huron-Vidal mixing rule are combined with infinite-dilution activity coefficients and the procedure is based on the reduced UNIQUAC model, suitable for infinite-pressure conditions. New binary interaction parameters are reported for studied systems for a wide range of pressure. By employing the pure component parameters with the values of infinite dilution activity coefficients, the solubility of mercaptans in water at dilute concentrations was predicted quite satisfactorily. The results of Root Mean Square Error (RMSE) illustrated good accuracy of the studied models for all systems considered in this work, with values of about 1.14-5.12%.

Distillation column is one of the effective unit operations that is commonly used to separate chemical mixtures. The only drawback of this separation process is its huge energy consumption especially for a multicomponent separation process which involves a series of distillation columns. Therefore, an optimal sequence must be determined to address the issue. This research proposes the methodology to determine the optimal sequence of distillation columns by using driving force method. Then, thermal pinch analysis is applied to obtain further energy saving in the process. The case study selected is a distillation process to recover 5-component of natural gas liquid (NGL) mixture. Based on the input data, the driving force sequence is determined first and simulated together with a conventional sequence (direct sequence). Then, the extracted data from the simulation will be used for thermal pinch analysis via problem table algorithm (PTA). From the results of PTA, energy consumption between both sequences were compared including the energy consumption before and after the thermal pinch analysis. In addition, economic analysis has been performed as well to indicate which sequence has lower capital and operating costs based on the proposed heat exchanger network (HEN). According to the results, the combination of the driving force and thermal pinch analysis methods has successfully recorded 48% of energy savings and operating cost, and 58.2% capital cost saving compared to the conventional sequence (direct sequence). Therefore, it can be said that the proposed framework has a great potential to be employed towards the process and economic feasible distillation process.

2 Mercaptan in Methyldiethanolamine (1) + Water (2) with w 1 = 3 0.25 and 0.50 at temperature of 298 to 348K using Inert Gas dilution in a mass fraction of 25%, and 50% of methyldiethanolamine (MDEA) aqueous 19 solution within the temperature range of 298-348 K at atmospheric pressure, were measured. 20 An inert gas stripping method was used to perform all the measurements. The new values of 21 Henry's Law Constant and the activity coefficients in infinite dilution correlation with solute 22 molecular size were explained. The influence of the solvent is discussed taking into 23

Combined degumming and bleaching is the first stage of processing in a modern physical refining plant. In the current practice, the amount of phosphoric acid (degumming agent) and bleaching earth (bleaching agent) added during this process is usually fixed within a certain range. There is no system that can estimate the right amount of chemicals to be added in accordance with the quality of crude palm oil (CPO) used. The use of an Artificial Neural Network (ANN) for an improved operating procedure was explored in this process. A feed forward neural network was designed using a back-propagation training algorithm. The optimum network for the response factor of phosphoric acid and bleaching earth dosages prediction were selected from topologies with the smallest validation error. Comparisons of ANN predicted results with industrial practice were made. It is proven in this study that ANN can be effectively used to determine the phosphoric acid and bleaching earth dosages for the combined degumming and bleaching process. In fact, ANN gives much more precise required dosages depending on the quality of the CPO used as feedstock. Therefore, the combined degumming and bleaching process can be further optimised with savings in cost and time through the use of ANN.

The focus of this research was to investigate and study the cogeneration potential in PTA production plant for reducing the emission to the environment due to high energy consumption in the respective plant. Currently, the total power requirement of the plant is about 26 MW per month in which fortunately, the Energy Improvement Team manage to locally generate 6 MW by using the expander and another 6 MW by using the steam turbine. However, through this new improvement project, it still contributes up to approximately 49,500 tonne CO 2 emission per year. In view of that situation, the potential of cogeneration is studied in this research with the main objective to reduce the carbon dioxide emission to the environment. Gas turbine system is selected over other Cogeneration or Combined Heat and Power (CHP) technologies due to several reasons such as power demand are continuous as well as high availability of natural gas in the plant[1]. In this study, the by product from the gas turbine (exhausted hot gases from turbine), will be utilized for local heating; the hot oil system facility. A preliminary design of gas turbine engine with heat recovery system has been carried out and research study had attested cogeneration has high potential to reduce the emission up to approximately 40,500 tonnes per year with reasonable annual percentage of emission savings up to 18.2%. The gas turbine design also manages to reduce the utilities and electricity costs in the plant of approximately RM 14 million per year which is accounted for 25% savings. Shaft work produced by the turbine is used to power the air compressor of axial flow type which amount up to 20 392.64 kW and producing net power of 29.61 MW before being transformed into electricity for domestic application in PTA plant and sales purpose. For the heat recovery system, an amount of 20 934 kW have been recovered from the exhausted air with temperature of 493.29 °C. Overall thermal efficiency of the system is determined to be 70.71% while the payback period of the gas turbine engine is determined to be 6 years with net present value of RM 347 491 087 and rate of return of 18.91%. Therefore, it is really a valuable and worth effort to install the new gas turbine engine in the respective plant. Through the implementation of this new gas turbine, not only the emission can be reduced but also impact a significant reduction in operating cost. Therefore, it is really a valuable and worth effort to install the new gas turbine engine in the existing PTA plant to sustain the environment.

International audience; Mercaptans (RSH) or thiols are odorous substances offensive at low concentration and toxic at higher levels. The presence of mercaptans as pollutants in the environment creates a great threat on water and air safety. In this study, the solubility of mercaptans in water was studied through the use of apparent Henry's Law constant (H) and infinite dilution activity coefficients (γ ∞). These thermodynamic properties are useful for environmental impact studies and engineering 2 design particularly in processes where dilute aqueous systems are involved. The aim of this paper is to develop a new thermodynamic correlation for estimation of apparent Henry's Law constant (H), infinite dilution activity coefficient (γ ∞) and solubility of C1-C4 mercaptans including their isomers in pure water. This correlation was developed based on compiled literature data. New measurements of apparent Henry's Law constant and infinite dilution activity coefficients of methyl mercaptan and ethyl mercaptan in water were carried out to validate the developed correlation. Validation with new measurement data showed a good consistency with low differences (less than 5%) for majority of the data. Additionally, heat of absorption of various mercaptans in pure water was discussed based on temperature influence, Henry Law Constants and solubility.