An Identification Size of The Interdigitated Flow Field on Pressure Loss Effects and Efficiencies in Vanadium Redox Flow Battery

In vanadium redox flow battery (VRFB), the active area for charge-discharge plays an important role on the optimization of the system. In this work, the optimum flow rate and current density of Nafion 117 membranes were examined and compared using 5cm2 and 25cm2 size of interdigitated flow field to operate VRFB at maximum efficiencies and discharge capacity. During discharge, flow field 25cm2 showed the highest discharge capacity of 367.5mAh at 10mAcm-2 as compared to 5cm2 flow filed which gave 221.9mAh. For battery efficiencies, three different parameters showed significant effects on different size of interdigitated flow field. 25 cm2 size of interdigitated flow field gave higher efficiencies than 5.0 cm2 up to 98%. This research offers fundamental understandings that bigger active area is needed to fully utilize the performance of VRFB.

Optimisation of degreemont water treatment package on Kedung Halang water treatment plant, Bogor, West Java

To provide drinking water in Bogor Regency, PDAM Tirta Kahuripan has several Water Treatment Plants (WTP) Kedung Halang WTP. Kedung Halang WTP consists of two water treatment packages, Indisi and Degreemont, with an average production of 37.3 L/s and 83.9 L/s, respectively. The purposes of this research are to evaluate the performance of the operating unit and process on the Degreemont Package and to provide optimisation recommendations based on the evaluation result. Steps in this research include evaluating the existing condition, providing recommendations, and analysing the quality of water produced. The evaluation found that one of the parameters did not fulfil the design criteria: the G.Td value on coagulation. The evaluation result of maximum flow rate is 125 L/s on intake, 150 L/s on coagulation, 130 L/s on flocculation and sedimentation, and 200 L/s on filtration. Thus, the optimum flow rate that can be operated is 125 L/s. The turbidity of the water produced has met the drinking water standard according to Minister of Health Regulation No. 492 of 2010, with removal efficiency above 95%. According to the result, it can be said that Degreemont Package is qualified to be applied as a drinking water treatment.

Karakteristik Hydrocyclone untuk Pemisahan Minyak dan Air

Eksplorasi minyak bumi dari sumur-sumur yang sudah tua menghasilkan minyak dengan kandungan air tinggi. Hydrocyclone suatu alat yang berfungsi untuk pemisahan cair-cair berdasarkan perbedaan berat jenis setiap komponen. Pemisahan ini terjadi dikarenanakan adanya gaya sentrifugal dan gaya gravitasi yang dihasilkan dari bentuk hydrocyclone yang seperti kerucut. Perancangan dan pembuatan hydrocyclone menghasilkan alat dengan spesifikasi sebagai berikut : diameter pipa masukan : 25,4 mm, diameter cylindrical section : 120 mm, tinggi cylindrical section : 120 mm, tinggi cone section : 600 mm, diameter pipa overflow : 25,4 mm, diameter pipa underflow : 25,4 mm. Laju alir optimum untuk pemisahan air-minyak tanah pada hydrocyclone adalah 91,8 liter/menit dengan kadar minyak tanah di overflow sebesar 11,4% dan kadar minyak tanah di underflow sebesar 3%.Petroleum exploration from old wells produces oil with a very high water content. Hydrocyclone is a device that functions for liquid-liquid separation based on differences in specific gravity of each component. This separation occurs due to the presence of centrifugal forces and gravitational forces resulting from cone-like forms of hydrocyclone. The design and manufacture of hydrocyclone produces tools with the following specifications: input pipe diameter: 25.4 mm, cylindrical section diameter: 120 mm, high cylindrical section: 120 mm, cone section height: 600 mm, overflow pipe diameter: 25.4 mm, underflow pipe diameter: 25.4 mm. The optimum flow rate for the separation of water-kerosene on hydrocyclone is 91.8 liters / minute with the level of kerosene in overflow of 11.4% and the level of kerosene in underflow of 3%.

A miniature piezomembrane hydraulic pump with decreasing chambers in succession

A miniature piezomembrane hydraulic pump with decreasing chambers in succession (PHPDCS) is presented. The number of chambers in PHPDCS decreases successively in two serial stages. The first stage consists of two chambers in parallel while the second stage consists of only one chamber. The proposed PHPDCS has the comprehensive advantages of serial and parallel connection of multi-chamber and has a high energy conversion efficiency. The prototype of PHPDCS is designed and manufactured. The output performance of PHPDCS under different external loads is investigated by experiments. Experimental results indicate that the optimum flow rate of the proposed PHPDCS is obtained when phase difference between two serial stages is 180°. The output performance of PHPDCS is superior to that of traditional piezoelectric pumps with two chambers in serial (PPCS). At 50 Hz, the maximum flow rate of PHPDCS under external load of 5 kPa is more than twice as high as that of PPCS. Under the external load of 10 kPa, the maximum flow rate of PHPDCS reaches 6.87 mL/min, whereas PPCS has no flow rate output.

Head lettuce production and nutrition in relation to nutrient solution flow

ABSTRACT The optimum flow rate of nutrient solution in hydroponic system can better nourish the crops, allowing healthy and faster growth of lettuce. However, flow also interferes with electric power consumption, so further researches are necessary, mainly on the effect of flow rate, nutrient accumulation and lettuce production. In this context, the aim of this study was to evaluate nutrition and production of head lettuce in relation to the nutrient solution flow in NFT hydroponic system. The treatments consisted of nutrient solution application at the flow rates 0.5; 1; 2, and 4 liters per minute in each cultivation channel. Five replicates per treatment consisted of 15 plants each. The flow in hydroponic systems to produce head lettuce alters the technical performance of the crop. Due to the greater nutrient accumulation in shoot and use efficiency of these elements, the highest production (g/plant) of head lettuce was obtained with a flow rate of 1 L/min of the nutrient solution.

Differentiation of Mamdani and Sugeno Fuzzy Inference System in developing Automatic Plant Watering Systems for Domestic Use

Water management systems are an essential requirement for maintaining plants. One of the major problems encountered in growing plants in houses, offices or buildings with in-house kitchen gardens is irregular irrigation patterns. This leads to over irrigation of pots or elongated durations of dry soil, both conditions ill for plant growth. This problem is further aggravated when manual irrigation ignores the environmental conditions and plant specific requirements. Utilizing Fuzzy logic for developing Automatic Plant watering systems provide flexibility in manipulating input parameters such as Temperature, Humidity, Soil Moisture and Plant Growth to determine optimum flow rate of the irrigation system. In this study, multiple fuzzy systems are developed for different environments and parameters. MATLAB is used for designing the fuzzy logic controllers using both Mamdani and Sugeno Models. The requirement for the system is to adjust the flow rate in accordance with the environmental conditions and plant requirements. The paper draws comparison between Mamdani and Sugeno methods on the basis of their performance characteristics for different environments. It also provides development of an effective controller for a watering system for household plantations.

A Novel PZT Pump with Built-in Compliant Structures

Different to the traditionally defined valved piezoelectric (PZT) pump and valveless PZT pump, two groups of PZT pumps with built-in compliant structures—with distances between the free ends of 0.2 mm (Group A) and 0 mm (Group B)—were designed, fabricated, and experimentally tested. This type of pump mainly contains a chamber 12 mm in diameter and 1.1 mm in height, a PZT vibrator, and two pairs of compliant structures arranged on the flowing channel. The flow-resistance differences between these two groups of PZT pumps were theoretically and experimentally verified. The relationships between the amplitude, applied voltage and frequency of the PZT vibrators were obtained experimentally, with results illustrating that the amplitude linearly and positively correlates with the voltage, while nonlinearly and negatively correlating to the frequency. The flow rate performance of these two groups was experimentally tested from 110–160 Vpp and 10–130 Hz. Results showed that the flow rate positively correlates to the voltage, and the optimum flow rate frequency centers around 90 Hz for Group A and 80 Hz for Group B, respectively. The flow rate performances of Group B were further measured from 60–100 Hz and 170–210 Vpp, and obtained optimal flow rates of 3.6 mL/min at 210 Vpp and 80 Hz when ignoring the siphon-caused backward flow rate. As the compliant structures are not prominently limited by the channel’s size, and the pump can be minimized by Micro-electromechanical Systems (MEMS) processing methods, it is a suitable candidate for microfluidic applications like closed-loop cooling systems and drug delivery systems.

ISOLATION, PURIFICATION, AND CHARACTERIZATION OF PORCINE SKIN COLLAGEN: ANALYSIS OF THE GLYCINE, PROLINE, AND HYDROXYPROLINE COMPONENTS USING HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY

Objective: The aim of this study is to produce collagen through the extraction and isolation of porcine skin.Methods: Collagen from porcine skin (Sus scrofa domesticus) was isolated, purified, and characterized. Major amino acid content of collagen (glycine,proline, and hydroxyproline) was determined. Samples were extracted with 0.5 N acetic acid and precipitated with 0.9 M NaCl. Characterization testsincluded those to determine the organoleptic content, pH, Fourier-transform infrared analysis, moisture content, ash content, viscosity, and Masson’strichrome staining on collagen tissue. The collagen was further analyzed using high-performance liquid chromatography using C-18® column anda fluorescence detector at 265 nm and 320 nm, acetic buffer (pH 4.2)–acetonitrile (55:45) as mobile phase, and optimum flow rate of 0.8 mL/min.Results: Our findings indicated that the best method for isolating collagen was with 0.1 M NaOH expressed by average contents of glycine, proline, andhydroxyproline in collagen which were 33.663±0.215%, 12.333±0.128%, and 11.303±0.354%, respectively.Conclusion: Porcine collagen has been successfully obtained with this method.

Effect of CO2 Flow Rate and Carbonation Temperature in the Synthesis of Crystalline Precipitated Calcium Carbonate (PCC) from Limestone

The effect of CO2 flow rate and carbonation temperature were studied in the synthesis of PCC from limestone using carbonation method. The synthesis was started by dissolving CaO that was obtained from calcination of limestone into HNO3 6M. The solution was then added with ammonia solution and then streamed with CO2 until pH 8 with flow rates of 0.5; 1.0; 1.5; and 2.0 L/min. The optimum flow rate obtained from this stage was then applied in the carbonation process with temperatures of 50, 80, 100, 150, 200, and 250 °C. The results showed that low flow rate give reasonably high yield but the yields obtained in every flow rate used in this work has insignificant difference based on F-test. The optimum flow rate used for the synthesis of PCC in the next stage was 0.5 L/min with a yield of 62.95%. Different carbonation temperature influences the polymorphs and crystallinity of the synthesized PCC. The synthesized PCC was analyzed by FT-IT, powder-XRD, SEM-EDX, and PSA. FT-IR analysis showed stretching vibrations of C–O at 1419, 1479, and 1384 cm-1 which correspond to calcite, vaterite, and aragonite respectively. Powder-XRD and SEM-EDX confirms that at the carbonation temperature of 50 °C, calcite and vaterite were formed, while at the carbonation temperature of 80 °C, mixture of calcite-vaterite-aragonite were obtained. Higher carbonation temperature changes the vaterite and aragonite polymorphs into calcite, and the best crystallinity was obtained at 250 °C. PSA analysis showed that the particle diameter of the synthesized PCC was about 3.58 to 38.14 µm.