Techno-economics of natural gas pipeline compression system.

The demand for the natural gas is on the increase as a result of industrialization and urbanization. There is need of transporting this natural gas from production fields to consumer market through long distances pipelines. Transporting natural gas through a long distance requires constructing of compressor station driven by a gas turbine at a suitable distance along the pipeline. Pipeline construction is capital expensive that requires important data such as the pipe diameter, pipe thickness, pipeline length, proper gas compressor and gas turbine sizes, flow rate and required operating pressure. The technical and economic success of a pipeline compressor station depends on the operation of gas compressor and gas turbine involved. Therefore, to techno-economic tool to assess the pipeline project becomes imperatives. The objective of this research is the application of TERA on gas turbine compressor station in natural gas pipeline taking into account the station location, equipment selection, power matching based on ambient temperature variation while optimizing for the project lifecycle lowest cost. The model and methodology developed to provide useful decision-making guide for Nigerian government on investment of Trans-Sharan gas pipeline. This research was divided into two aspects, the performance aspect, and the economic aspect. The performance presents a model for booster station definition along the gas pipeline. The model was developed using thermodynamic gas properties, HYSYS and Weymouth gas flow equation. The model also accounts for the variation in the elevation and ambient temperature at each of the compressor stations located along the pipeline network. For each of the stations gas compressor and gas turbine model was selected. The model has been verified using pressure ratio and a number of booster station spacing of a pilot project, Trans-Sahara gas pipeline (TSGP). The project was aimed at exporting natural gas from Niger Delta, Nigeria to the consumer market in Europe via Niger and Algeria. The project is expected to transport 30bcm/year of natural gas through 56-inch pipe diameter and a total distance of 4180km with 18 compression stations. For the power matching, the daily three hourly temperature measurements for winter, hot, and dry seasons were recorded for each of the compressor stations along the gas pipeline. The power requirement for the centrifugal compressors was calculated based on the three hourly intervals. The gas turbines were simulated in Turbomatch based on these ambient temperatures. The result shows that both the centrifugal compressor polytropic head and the gas turbine output power are strongly influenced by the ambient temperature with gas turbine power output dropping by average 0.95% for every 10oC rise in ambient temperature and the centrifugal compressor polytropic head increasing by average of.1% for every 10oC rise in ambient temperature vis-viz increase in the centrifugal shaft power. The major costs associated with the natural gas pipeline is the capital cost and operating cost. At baseline case, the project capital cost is USD 15.7 billion and the project lifecycle cost is USD 27.6 billion. The project life cycle cost is made of the following 33% fuel cost,10% maintenance cost, 26% pipeline cost, 6% gas turbine cost, 12% gas compressor cost, and 13% auxiliary cost. For this baseline, The NPV at 15% discount rate negative. For the optimised case, the studies considered two gas turbines of 43.3MW and 100MW capacities. For the first case, optimisation study was done for two 43.3MW gas turbine driving two gas compressors while for case 2, one 100MW gas turbine was used to drive one gas compressor. The result shows 10 number of compressor stations along the pipeline. The optimized result also shows a reduction in the lifecycle cost from USD 20.1 billion in 43.3MW to USD 18.8 billion in 100MW. The NPV at 15% discount rate for both engines is seen to be positive.PhD in Aerospac

Determination of the Phytochemical Constituents and Antifungal Properties of Annona senegalensis Leaves (African Custard Apple)

Phytochemical screening of Annona senegalensis leaves was carried out in order to identify and to quantify the bioactive compounds that are present in the plant. Methanol extracts and aqueous extracts of the plant leaves were screened for the presence of ten metabolites. The qualitative study indicated the presence of alkaloids, flavonoids, polyphenols, steroids, cardiac glycoside and carbohydrates for both the aqueous extracts and the methanol leaves extract. Tannins and terpenoids were only present in the aqueous extract and saponins were only present in the methanol extract. Anthraquinones were absent in both of the extracts. Quantitative analysis showed the amount of alkaloid that was present in both the leaves extract of Annona senegalensis. Antifungal activities of the methanol extracts and the aqueous extracts of Annona senegalensis were investigated and assessed against cultured Trichoderma spp fungus. The susceptibility of the tested fungus on the extracts was determined by measuring the diameter of the inhibition zones formed around the well. The highest anti-fungal activity was observed in the aqueous extracts of the leaf. This gave an inhibition zone of 14.5mm. The methanol extract of the leaf gave the lowest inhibition zone of 8.3mm. Keywords: Annona senegalensis, bioactive, extracts, metabolites, leaves, phytochemical, antifunga

Techno-economic evaluation of pipeline compression system: economic evaluation of the natural gas pipeline compression system - part 3

This paper presents the evaluation of the life cycle cost (LCC) of the natural gas pipeline investment using ‘’techno-economic and environmental risk assessment’’ (TERA) technique. The significance of this paper is to evaluate the cost implication of all the parts of this research work. The selected engines models for the gas compressor drive were developed based on public domain specification, using an inhouse engine performance simulation software: TURBOMATCH. The gas turbine engines were modelled to run at constant power amid high ambient temperature. The performance results were further used for the economic investigation using a developed model in MATLAB. These were investigated with respect to three seasons (winter, dry and hot season) of the years based on the location of this project (Trans- Saharan gas pipeline with 18 compression stations). Three economic conditions of 0%, 2% and 4% escalation rate of fuel and maintenance cost were investigated to analyse the LCC. The results obtained shows that the total LCC for the 0% escalation rate was approximately $32.01 billion. The fuel cost was 39.60% of the total LCC for the entire project. The operating and maintenance (O&M) costs, gas turbine, gas compressor, the pipeline with all accessories costs and emission tax attracted 10.1%, 6.89%, 9.95%, 28.89%, and 4.57%, respectively of the total life cost. The result also depicted that 2% and 4% escalation rate of fuel and O&M cost on the LCC result in 19.5% and 47.8% increased, respectively when compared with the 0% escalation rate at the end of project life. The result of the overall life-cycle cost of the pipeline investment represents the operational cost of the system. The proposed approach will help operators on the real potential cost of pipeline investment, taking into account the different cost element and ambient condition of the natural gas pipeline system. Importantly, this model can be applied or adapted to any natural gas pipeline transportation business

Isolation and characterization of a fatty acid from the seed extracts of citrullus lanatus (water melon)

A sample of powdered watermelon seeds sample was macerated with ethanol for two weeks using a maceration method. The mixture was stirred using magnetic stirrer, for 24 hours, in order to extract the powders. It was then decanted, filtered and concentrated on a rotavapor (R110) at 40 ºC in order to obtain the crude ethanol extract (F001). The crude ethanol extract was partitioned into aqueous methanol, chloroform, ethyl acetate and acetone in order to obtain F002, F003, F004 and F005 fractions respectively. The methanol fraction indicated strong activity in the antimicrobial test compared to other fractions. Based on these results, the methanol fraction was subjected to activity-guided chromatographic purification targeting the compound responsible for the observed activity. The methanol fraction (10 g) of the extracted seeds of Citrullus lanatus was chromatographed on a silica gel column, using different eluents. This afforded 117 fractions which were combined based on their thin layer chromatography (TLC) pattern. The pooled fraction (-62 – 67-) was further chromatographed in order to obtain the fatty acid. The structure of the compound was characterized – using,- Proton nuclear magnetic resonance (1H NMR), Carbon-13 nuclear magnetic resonance (13C NMR), Distortionless enhancement bypolarization transfer (DEPT), Fourier transform infrared spectroscopy (FTIR) spectroscopic techniques and Mass spectrometry (MS) analysis in order to propose the structure of the compound as a straight chain aliphatic dicarboxylic acid (3-methylnonadec-4,6-diene1,19-dioic acid)

Determination of surface radiation dose-rate in the environment of Kelantan State, Malaysia

Measurements of environmental surface radiation dose rate in Kelantan state, Malaysia was carried out using a portable hand held radiation survey meter and Global Positioning System (GPS). The surface radiation dose rates ranged from 44 to 500 nGy h-1. The measurements were done based on geology and soil types of the area. The mean radiation dose rate was found to be 209 ± 8 nGy h-1. Few areas of relatively enhanced activity were located in Pasir Mas, Tanah Merah and Jeli districts which have external gamma dose rates between 300 to 500 nGy h_1. An Isodose map of the state was produced using ArcGIS10 software version 10.1. To evaluate the radiological hazard due to terrestrial gamma dose, the annual effective dose equivalent (AEDE), the mean population weighted dose rate and cancer risk factor were calculated and found to be relative excess lifetime cancer risks were 1.280 mSv y-1, 18 mSv and 1.04×10-3 respectively

A model for booster station matching of gas turbine and gas compressor power under different ambient conditions

Transporting natural gas across different locations require compressor stations to provide the pressure needed to keep the gas moving. This paper presents a model for matching the gas turbine and gas compressor power required under different environmental conditions to support the continuous gas transmission across other locations. The trans-Saharan gas pipeline (TSGP) project proposed to transport gas from Nigeria to Algeria has been used as a case study in this paper. The TSGP project is a Nigerian Government initiative to rejig its gas development and transportation infrastructure to meet its internal and external market demand. The numerical method used in this paper integrates the effect of the ambient temperature in the power matching of the gas turbine and gas compressors. There are 18 compressor stations across the TSGP network, and compressor station 2 is used as the reference point. The daily temperature fluctuation is segmented into hours of the day, emphasising considerable ambient temperature variation at 3:00 h, 9:00 h, 15:00 h. One benefit of the model against others in the open literature is accounting for changes in the ambient temperature along the pipeline network and gas compression stations. Accounting for changes in ambient temperature provides accuracy to near real-life operational experience for gas distribution via pipelines. The model also accounts for variations in turbine entry temperature (TET) to compensate for changes in the ambient conditions to meet the power requirements of the gas turbine and the gas compressor. The results show that for every 1% increase in ambient temperature, a 3.5% increase in power is required to drive the gas compressor and a 1% decrease in gas turbine output power. The effect of the 1% increase in ambient would require a 3.5% increase in TET to meet both the gas turbine and gas compressor requirement

Radiological information of Kelantan - a review

This study reviewed radiological research works conducted in the state of Kelantan, Peninsular Malaysia. A total number of eleven research articles available to the authors were reviewed and reported accordingly in this paper. From the studies it was observed that not much has been done in revealing the radiological state of the region despite been blessed with abundant granitic rock deposit. Some of the papers reviewed reported the presence of high activity concentration of naturally occurring radionuclides i.e. 238U, 232Th, 226Ra, 228Ra, 222Rn, and 40K in some study areas like work of (Siti Afiqah et al, 2012; Mohammed Kasim et al, 2011 etc.) while few studies were reported to be below the global and Malaysian average as can be seen in the tex

Natural radioactivity and associated radiation hazards in soil of Kelantan, Malaysia

Radiological effects due to external and internal exposure to natural radiation associated with the natural radionuclides 226Ra, 232Th, and 40K in soil of Kelantan, Malaysia was carried out. Terrestrial gamma radiation dose rates (TGRD) measurement was carried out using a portable [NaI(TI)] micro roentgen (µR) survey meter and hyper purity germanium (HPGe) detector for the activity concentrations of 226Ra, 232Th, and 40K in soil samples. The mean TGRD was found to be 209 nGy h−1 and from soil samples analyzed, the mean activity concentrations of 226Ra, 232Th, and 40K were found to be 82 Bq kg−1, 123 Bq kg−1, and 643 Bq kg−1 respectively, which were both about 3 times higher than the Malaysian average as reported by UNSCEAR 2000. The mean radium equivalent (Raeq), absorbed dose rates (D), annual effective dose (H), annual gonadal dose equivalent (AGDE) as well as external and internal radiation hazard index (Hex), which were the indicators of radiological health hazards, were found to be 307 Bq kg−1, 139 nGy h−1, 0.22 mSv y−1, 969.422 µSv y−1, 0.653 and 1.05, respectively