Anodic oxidation has been widely used to modify the surface properties of titanium in order to improve the biocompatibility after implantation. In this study, high purity titanium foils were exposed in a mixture of β-glycerophosphate disodium salt pentahydrate (β-GP) and calcium acetate monohydrate (CA). The parameters for anodic oxidation method such as applied voltage (50-350 V), current density(10-70 mA.cm-2), electrolyte concentration (0.02 M β-GP + 0.2 M CA, 0.04 M β-GP + 0.04 M CA) , anodising time (5-10 mins), agitation speed (300-1500 rpm), ultrasonic amplitude (20-60 μm) and bath temperature (4-100 °C) were varied to investigate the impact on the surface properties of titanium. The results showed that surface of the titanium foil appeared to be highly porous and demonstrated high crystallinity as well as high hydrophilic properties especially when the parameters of anodic oxidation have been varied. This study also proposes two novel methods particularly to accelerate the bone-like apatite formation on the anodised titanium in a shorted time: (1) UV irradiation during in vitro testing and (2) adding additives in electrolyte. After soaked and irradiated with UV in simulated body fluid (SBF) for 7 days, highly crystallised bone-like apatite was fully covered on the anodised surface. Interestingly, the smooth and partially porous surface of the anodised titanium was observed to be fully covered by the bone-like apatite layer, which contradict previous research results. The mechanism for growth of bone-like apatite was developed and involved several stages from the existence of hydroxyl groups (•OH) under the UV irradiation has been disclosed thoroughly. Further, additives such as sulphuric acid (H2SO4), hydrogen peroxide (H2O2) and sodium hydroxide (NaOH) were added into the electrolyte were also able to accelerate the formation of bone-like apatite because of the presence of (•OH), tricalcium phosphate (Ca3O8P2), calcium diphosphate (Ca2O7P2), calcium titanate (CaTiO3) or sodium titanate (Na2Ti3O7) on the anodised surface, which able to induce the nucleation site of bone-like apatite

Lee, Te Chuan

English

Parabens are chemicals that are frequently used as preservatives in numerous cosmetic products. In recent years, the safety concern over these compounds has grown due to their endocrinedisrupting activity. In this research, a novel green magnetic molecularly imprinted polymer

(GMMIP) was synthesised using propylparaben as a template and then applied as an adsorbent to selectively recognise and remove parabens from cosmetic samples. The green strategies were introduced by using Persicaria odorata or Kesum leaf extract as a reducing agent to synthesise

green magnetic nanoparticles (MNP) as a magnetic core, and deep eutectic solvent (DES) has been designed as an environmentally friendly functional monomer that was used in the preparation of GMMIP. The GMMIP was characterised using Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), and BrunauerEmmett-Teller (BET). The results of FESEM and BET indicated that the GMMIP exhibited an irregular spherical shape and mesoporous characteristics with a pore size of 17.74 nm. The adsorption pH, kinetics, isotherms, and thermodynamics parameters were performed to investigate the interactions that take place between GMMIP and propylparaben. The adsorption processes appeared to best fit the pseudo-second-order kinetic and Freundlich isotherm models at an optimum pH of 12. Findings from a thermodynamics study revealed the adsorption process

was exothermic, spontaneous, and more favourable at 298 K. The optimised GMMIP was applied as an adsorbent to remove the parabens from cosmetic samples. When compared to methylparaben and ethylparaben, the GMMIP had the highest selectivity and effectively removed propylparaben, with recoveries ranging from 75.6% to 113.3%. It was found that the limits of detection (LOD) and quantification (LOQ) were between 0.03 and 0.05 mg/L and 0.11 and 0.16 mg/L, respectively. The synthesised GMMIP proved to be a convenient and effective adsorbent to remove parabens from cosmetic products. © 202

Ramin, Nursyahera Azreen

Asman, Saliza

UTHM Institutional Repository

Synthesis and evaluation of green magnetic mesoporous molecularly imprinted polymers for adsorption removal of parabens from cosmetic samples

'30000002161854* U N I V E R S I T I T U N H U S S E I N O.N'N M A L A Y S I A PENGESAHAN STATUS TESIS I M P R O V E M E N T O F S C R E W P R E S S P R O D U C T I O N IN P A L M O I L M I L L USING F U Z Z Y L O G I C S Y S T E M SESI P E N G A J I A N : 2008/2009 Saya WAN ZUI.KAKNAIiN BIN OTIIMAN mcngaku mcmbcnarkan Tcsis Sarjana ini D I M N I P . m <li Perpustakaan dengan syarat-syarat kegunaan seperti beriknt: 1. Tcsis adalali hakmilik Universiti Tun I lussein Onn Malaysia. 2. Perpustakaan dibenarkan membuat salinan untuk tujuan pengajian sahaja. 3. Perpustakaan dibenarkan membuat salinan tcsis ini sebagai balian pertukaran antara iiistilusi pengajian tinggi. 4. ** Silatandakan(V) SULIT (Mengandungi maklumat yang bcrdarjab kcselamatan atau kepentingan Malaysia seperti yang tcrmaktub di dalam AKTA RAIISIA RASMI 1972) • T E R H A D TIDAK. T E R H A D (Mengandungi maklumat TERHAD yang telah ditcntukan oleh organisasi/badan di mana penyelidikan dijalankan) Disahkan Oleh ( T A N D A T A N G A N PENULIS) A l a m a t T c t a p : 11051 Taman Sri Jaya 3, Gong Pauh, 24000 Chukai Kcmanan, Tcrcngganu PROF. DR M A N BIN HASSAN Tarikh Tarikh : 'Jo/c CATATAN: Jika tcsis sarjana ini SULIT atau TERHAD, sila lampirkan sura! danpada pilink berkuasa'organisasi berkenaan dengan mcnyatakan sckah ^cb.sb d.:r, tcmpoh tesis ini pcrlu di kclaskan sebagai SULIT atau TERHAD. "I hereby declare that I have read this thesis and in my opinion this thesis in terms of content and quality requirements fulfills the purpose for the award of the Degree of Master of Mechanical Engineering" IMPROVEMENT OF SCREW PRESS PRODUCTION IN PALM OIL MILL USING FUZZY LOGIC SYSTEM W A N ZULKARNAIN BIN O T H M A N A thesis submitted in fulfillment of the requirement for the award of the Degree of Master of Mechanical Engineering Faculty of Mechanical and Manufacturing Engineering Universiti Tun Hussein Onn Malaysia JUNE, 2008 I hereby declare that the works in this thesis is my own except for quotations summaries which have been duly acknowledged. Signature Name of Author Date J^k&H W A N ZULKARNAIN..BIN O T H M A N iii Dedicated to my beloved wile and children iv ACKNOWLEDGMENT Bismillaahirrahmaanirrahiim... Praise be all to Allah SWT, the Most Gracious, the Most Merciful. Shalawat and salam be to Rasulullah Muhammad saw. By the grace of Allah SWT, this thesis is finally completed and submitted to Faculty o f Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia, to full fill the requirements for the Degree of Master o f Mechanical Engineering. I would like to take this great opportunity to express my warmest gratitude to my supervisor Professor Dr. Sulaiman bin Hassan and co-supervisor Assoc. Professor Dr. Mohd Nor bin Mohd Than for their guidance, concern and strong support throughout the completion of this thesis. Their enthusiasm has been a great source of inspiration to me and it gives me a great sense of honour to be under their wings. Great thanks to my friends who have assisted in making this thesis a wonderful one and finally to those who have contributed to the success of this thesis, especially Kumpulan Kilang Sawit RISDA Bhd. Without them this thesis would not have been possible. V ABSTRACT A screw press machine is used to compress the fruit mash between the main screw and the travelling cones to extract the palm oil. The position of the cones against the discharge end o f the press cage determines the pressure. The pressure controller is an important factor in determining the oil loss and nut breakages. A conventional control system which is the band control system, uses a kilowatt meter as a controller in adjusting the press cage pressure. However, the screw press machine can be improved in order to reduce the oil loss and nut breakages. Not much researches has been conducted on reducing the nut breakages as well as oil loss. Therefore, the objective of this study is to minimise the oil loss and broken nuts. The objective can be achieved through upgrading the screw press machine and the use of fuzzy control system. During the course of this research project, the hydraulic system of the screw press machine was upgraded by utilising the proportional pressure relief valve. A current transducer was used to measure the motor current load. A ladder diagram program and fuzzy logic algorithm were written and downloaded into the programmable logic control to regulate the press cage pressure. For comparison purposes, a band control system and fuzzy control system were implemented in the control environment. The performances of both systems were compared in a number of tests. The first test was the oscillation of motor current load with the performance of fuzzy control system that was stabilised at 8.33mA. This is due to the reaction o f fuzzy pressure controller in regulating the proportional pressure relief valve. The fuzzy control system is able to reduce 1.20% of oil loss compared to tiie band control system. The percentage o f the broken nuts of the fuzzy control system was reduced by 3.55%. This implies that the objective to reduce the breakages is achieved. Thus, the screw press machine with a fuzzy control system is found to be significantly more efficient than the band control system. vi ABSTRAK Mesin penekan skru digunakan untuk memampatkan lecekan buah antara skru utama dan kon penggerak bagi tujuan mengekstrak minyak sawit. Kedudukan kon di hujung keluaran sangkar pemerah menghasilkan tekanan. Pengawal tekanan merupakan satu faktor yang utama terhadap kehilangan minyak dan biji pecah. Sistem kawalan lazim yang sedia ada iaitu sistem kawalan jalur, menggunakan kilowatt meter sebagai pengawal bagi tujuan melaras tekanan di dalam sangkar pemerah. Oleh yang demikian, prestasi pemprosesan mesin pemerah skru ini, beipotensi untuk dimajukan bagi mengurangkan lagi kehilangan minyak dan biji pecah. Tidak banyak penyelidikan yang telah dijalankan dalam mengurangkan kehilangan minyak dan biji pecah. Oleh itu, objektif kajian ini adalah untuk mengurangkan kehilangan minyak dan biji pecah. Objektif kajian ini boleh dicapai dengan menaik taraf mesin penekan skru dan penggunaan sistem kawalan kabur. Sepanjang projek penyelidikan ini, sistem hidraulik mesin penekan skru telah dinaik taraf dengan menggunakan injap pelega tekanan berkadar. Pencerap arus elektrik telah digunakan untuk mengukur muatan arus elektrik motor. Aturcara PLC dan algoritma logik kabur telah ditulis dan di muat turun ke PLC bertujuan untuk mengawal tekanan sangkar pemerah. Perbandingan antara sistem kawalan jalur dan sistem kawalan kabur telah dilaksanakan dengan mengadakan beberapa ujian. Ujian pertama adalah ayunan muatan arus elektrik motor dan didapati prestasi sistem kawalan kabur adalah stabil pada 8.33mA. Ini adalah disebabkan oleh tindakan pengawal tekanan kabur dalam mengatur injap pelega tekanan berkadar. Sistem kawalan kabur didapati mampu mengurangkan 1.20% kehilangan minyak berbandingan sistem kawalan jalur dan peratusan biji pecah sistem kawalan kabur adalah lebih baik dengan perbezaan sebanyak 3.55%. Ini menunjukkan, objektif kajian iaitu untuk mengurangkan kehilangan minyak dan biji pecah telah dicapai. Oleh itu, mesin penekan skru dengan sistem kawalan kabur adalah lebih baik berbanding dengan sistem kawalan jalur. TABLE OF CONTENTS CHAPTER TITLE PAGE TESTIMONIAL ii DEDICATION iii ACKNOWLEDGMENT iv ABSTRACT V ABSTRAK vi TABLE OF CONTENTS vii LIST OF TABLE xi LIST OF FIGURE xii NOMENCLATURE xiv ABBREVIATIONS XV LIST OF APPENDIX xv i I PALM OIL SCREW PRESS 1.1 Introduction 1 1.2 State of The Art in Palm Oil Mill Screw Press 3 1.3 Problem Statement 4 1.4 Objectives 5 1.5 Thesis Outline 5 viii II LITERATURE REVIEW 2.1 Introduction 6 2.2 History o f Palm Oil Extraction 7 2.3 Screw Press Power Consumption 8 2.4 Basic Principles of the Screw Press 9 2.5 Screw Press Conventional Control System 10 2.5.1 Band Control System II 2.5.2 Proportional Control System 11 2.6 Comparison of the Performance between the Band and the Proportional Controller 12 2.7 Fuzzy Control 14 2.7.1 Fuzzy Sets 15 2.7.2 Fuzzy Set Membership Functions 16 2.7.3 Fuzzy Set Operations 17 2.7.4 Union or Max 17 2.7.5 Intersection or Min 17 2.7.6 Fuzzy Logic Controller 18 2.7.7 Knowledge Base IS 2.7.8 Fuzzy Set Variables 19 2.7.9 Inference Rules 19 2.7.10 Fuzzification 20 2.7.11 Defuzzification 21 2.8 Reviews o f Fuzzy Logic Controller Application 23 2.9 Application of Fuzzy Logic in PLC 25 2.10 Conclusion 28 ix III SCREW PRESS FUZZY LOGIC CONTROLLER DESIGN 3.1 Introduction 30 3.2 Screw Press System Development 31 3.3 Fuzzy Logic Control System Development 35 3.3.1 Fuzzy Pressure Controller 37 3.4 Fuzzy Pressure Controller Development 38 3.5 Fuzzy Logic PLC Programming Development 48 3.5.1 Assigning of Inputs and Outputs 49 3.6 PLC Program 50 3.7 Conclusion 50 IV EQUIPMENT SETUP 4.1 Introduction 51 4.2 Current Transducer (CT) 55 4.3 Proportional Pressure Relief Valve (PPRV) 56 4.4 Fuzzy Logic PLC 57 4.5 Complete Equipment Setup 60 4.6 Conclusion 61 V EXPERIMENTAL RESULTS 5.1 Introduction 62 5.2 Oil Loss and Broken Nuts versus PPRV Command Value 63 5.3 Regression Analysis of Screw Press X Motor Current Load 64 5.4 Simulation Studies 65 5.5 The Performance of the Fuzzy Pressure Controller 68 5.6 Comparison of Oscillation Current Load 70 5.7 Comparison of Power Consumption 71 5.8 Process Performance 72 5.9 Financial Implication of Oil and Free Kernel Loss 75 5.10 Conclusion 76 VI CONCLUSION AND SUGGESTION 6.1 Conclusion 77 6.2 Contribution and Future Research 78 REFERENCES 80 APPENDIXES 85 X I LIST OF TABLE TABLE TITLE PAGE 2.1 Comparative press trial between the band control and proportional control system (Ongand Yong, 1987) 13 2.2 Example of rule matrix for two input and single output system 20 2.3 Inferred fuzzy output sets 21 3.1 The linguistic variable and the magnitude of input error 39 3.2 Fuzzy rules 42 3.3 Fuzzy rules application 46 3.4 Fuzzy control output 47 3.5 I/O words 49 3.6 I/O bit 49 5.1 Summary of press cake results 73 5.2 Financial implication of oil and free kernel loss 75 xii LIST OF FIGURE FIGURE TITLE PAGE 1.1 Palm oil processing 1 1.2 The operation of screw press 2 1.3 Schematic diagram of the hydraulic system for the hand control system (Bosh Rexroth,2000) 4 2.1 Relative distance of the travelling cone, d, 8 2.2 Reaction of the travelling cone at variance with the force 9 2.3 Fuzzy membership 16 2.4 Block diagram of a fuzzy logic controller 18 2.5 Fuzzy input membership 19 2.6 Fuzzy input sets 20 2.7 Fuzzy output sets 22 3.1 Overview screw press fuzzy logic controller design work flow 31 3.2 Screw press system schematic diagram 32 3.3 Parts of screw press system: (a) press mechanism; (b) hydraulic system; and (c) fuzzy logic control system 33 3.4 The structure of a fuzzy logic control system 35 3.5 The structure of a fuzzy pressure controller 37 3.6 Input membership functions for current error (ie) and current error variance (Az'e) 40 3.7 Fuzzy output membership function 41 3.8 The degree of membership function for ie and Me 45 3.9 Fuzzy output control surface 47 3.10 Control flow of pressure control 48 Band control system setup Fuzzy logic control system setup Fuzzy logic control system configuration Wiring connection Current transducer (CT) The installed proportional pressure relief valve (PPRV) on the hydraulic system Detailed schematic of the proportional pressure relief valve (PPRV), (Bosch Rexroth, 2002) Programmable logic controller (PLC) with fuzzy logic unit Overall schematic of the implementation equipment setup Linear analogue output characteristic of the analogue output unit Complete equipment setup for the screw press fuzzy control system The effect of PPRV command value to the oil loss and broken nut Command values and current load data fitted to a regression model Fuzzy logic control system The increment and decrement of hydraulic cylinder pressure were determined by fuzzy output variable, u Current error (ie) performance test Current error variance (A/e) performance test Fuzzy output (M) performance test Comparison of signal level between band control system and fuzzy control system Power consumption between band control system and fuzzy control system NOMENCLATURE SYMBOL DESCRIPTION A Ampere Ai Rod side piston area A2 Piston surface area d Relative distance F Force 'a Actual current ie Current error ir Desired current load mA Milliampere Pi Pressure acting on the rod side of the hydraulic piston Pi Pressure acting on hydraulic piston surface Ppc Press cage pressure Pr Hydraulic pressure 11 Output of Fuzzy Controller Ale Current error change APf Fuzzy output variable Apr Hydraulic pressure output variable Membership grade of the j th Membership grade of the / th ABBREVIATIONS AID Analogue to Digital AC Alternate Current COG Centre of Gravity CPU Central Processing Unit CT Current Transducer D/A Digital to Analogue DC Direct Current DM Data Memory FFB Fresh Fruit Bunch FSS Fuzzy Support Software HMPB Harrisons Malaysian Plantations Berhad I/O Input/Output IR Internal Relay KW Kilowatt MPD Mass Passing to Digester NL Negative Large NM Negative Medium NS Negative Small PD Proportional-Derivative PI Proportional-Intergral PID Proportional, integral and derivative PL Positive Large PLC Programmable Logic Controller PM Positive Medium PPRV Proportional Pressure Relief Valve PS Positive Small rpm revolutions per minute SBB Binary Subtraction ZR Zero xvi LIST OF APPENDIX APPENDIX TITLE PAGE A Flow Chart 86 B PLC Ladder Diagram 100 C The Operation of PLC Program 10 8 D Simulation of Screw Press Fuzzy Logic Controller 112 CHAPTERI PALM OIL SCREW PRESS 1.1 Introduction The palm oil mill processes is shown in Figure 1.1. On the arrival of the fresh fruit bunch (FFB), the FFB are steam sterilised where the fruits soften and easily detached from the stalk. These detached fruits are further softened with steam in digesters. The digester mash is then passed to the screw press where the oil and the nut are extracted. Find Shift Eflfesnt p l t Figure 1.1: Palm oil processing 2 There are various types of screw presses used for the extraction of palm oil. The earliest was introduced to the palm oil industry in the early 1960's. This type of machine had been developed for a multitude of applications, both for extraction and extruding (Sivalingam, 1999). The concept of the screw press is to compress the fruit mash between the main screw and the travelling cones to extract the palm oil. The position of the cones, as shown in Figure 1.2, against the discharge end of the press cage determines the pressure maintained on the mash i.e. smaller slot between cone and press cage will result in higher pressure and vice versa. Figure 1.2: The operation of screw press In the screw press, the stability of the press cage pressure is an important factor in determining the oil loss and nut breakage in the press cake. A high pressure causes a better recovery of the oil but unfortunately produce a higher nut breakage. The effectiveness of the screw press is very critical in optimising the oil extraction. Ineffective press will result in oil loss and nut breakage and also high maintenance cost of the machine. Engineers and researches have always tried to optimise the oil press operation and this research is studying one method of achieving this. Therefore a fuzzy logic system has been chosen in this research to stabilise the pressure in the press cage. 3 Fuzzy logic system has been successfully used for a wide number of applications dealing with complex and non-linear processes, wherein they are proved to be robust and less sensitive to parametric variations and noise than conventional controllers (Roger Jang and Gulley, 1997). In addition, fuzzy logic system has been proven to reduce the oscillations, smoothing the output as far as the error decreases. This nonlinear characteristic of the controller is a great advantage and was not possible by a linear Proportional-Derivative (PD) controller (Corbet and Lawrence, 1996). 1.2 State of The Art in Palm Oil Mill Screw Press The screw press system is one of the least understood processes in a palm oil mill even though it is one of the most important. Hence, very little progress in the quantitative understanding of screw presses has been achieved even though they have been used in palm oil mills for the past fifty years. In view of the oil losses improvement, the extraction method has gone through some evolution in term of method of extraction, design and control (Sivasothy, 1993). One method of controlling the press cone is utilising kilowatt set point. The press cone movement depends on the kilowatt set point. When the measurement is less than set point, the press cone will move in and vice-versa (Yee, et. al., 1987). These conventional pressure control systems are used extensively in the palm oil industry. This controller is sometime referred to as band control system. However, these controllers do not take the interaction effect into consideration and the design and adjustment are difficult despite of their high performance (Burhan Sidek, 1988). The pressure inside the cage must be measured accurately to ensure effective control. Thus the method of measuring the pressure is therefore very important. Pressure can be measured indirectly by the measurement of the power consumed by the screw press. In general, the pressure can be controlled and it relies on the precision of the instrument and the screw press condition (Sivasothy, 1993). 4 To summarise, an extensive review of the literature have shown that there are limited number of published papers on the topic of palm oil mill screw press control system. As such, that this will remains as an area in which substantive research needs to be conducted. This research project will attempt to introduce another mean of controlling pressure in the palm oil mill screw press. 1.3 Problem Statement In conventional screw press control system, as shown in Figure 1.3, the press cage pressure is measured via the screw press motor current load by using the current transducer. If the level is rises, the travelling cone will move away from the press cage opening. By doing this, the pressure inside the press cage will be reduced. However the regulating pressure in the press cage efficiency is relatively poor and produces a fluctuation pressure. The fluctuation press cage pressure cause the increment of oil losses and nut breakage. Figure 1.3: Schematic diagram of the hydraulic system for the band control system (Bosch Rexroth, 2000) 

In vitro bioactivities of anodised titanium in mixtrue of B-Glycerophosphate and calcium acetate for biomedical application

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