DEGRADATION OF PALM OIL MILL SECONDARY EFFLUENT (POMSE) USING by broverya76

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									DEGRADATION OF PALM OIL MILL SECONDARY EFFLUENT (POMSE)
                       USING BIOSTRUCTURE




               NURUL BAHIYAH BINTI ABD WAHID




          A project report submitted in partial fulfillment of the
    requirements for the award of the degree of Master of Engineering
                  (Civil- Environmental Management)




                       Faculty of Civil Engineering
                      Universiti Teknologi Malaysia




                               JUNE 2007
                                                  PSZ 19:16 (Pind. 1/97)
                        UNIVERSITI TEKNOLOGI MALAYSIA


               BORANG PENGESAHAN STATUS TESIS ?
JUDUL :             DEGRADATION OF PALM OIL MILL SECONDARY EFFLUENT
                              (POMSE) USING BIOSTRUCTURE

                              SESI PENGAJIAN :    2006/2007

 Saya :                       NURUL BAHIYAH BINTI ABD WAHID
                                      (HURUF BESAR)


mengaku membenarkan tesis (PSM/Sarjana/Doktor Falsafah)* ini disimpan di Perpustakaan
Universiti Teknologi Malaysia dengan syarat-syarat kegunaan seperti berikut :

1. Tesis adalah hak milik Universiti Teknologi Malaysia.
2 Perpustakaan Universiti Teknologi Malaysia dibenarkan membuat salinan untuk tujuan pengajian
    sahaja.
3. Perpustakaan dibenarkan membuat salinan tesis ini sebagai bahan pertukaran antara institusi
    pengajian tinggi.
4. **Sila tandakan ( )


                SULIT     (Mengandungi maklumat yang berdarjah keselamatan atau
                          kepentingan Malaysia seperti yang termaktub di dalam
                          AKTA RAHSIA RASMI 1972)

           v    TERHAD (Mengandungi maklumat TERHAD yang telah ditentukan
                       oleh organisasi/badan di mana penyelidikan dijalankan)


                TIDAK TERHAD



                                                               Disahkan oleh


__________________________________                   _______________________________
       (TANDATANGAN PENULIS)                            (TANDATANGAN PENYELIA)

Alamat Tetap :
LOT 1099, SIMPANG LIMA,                                       DR AZMI BIN ARIS
34200 PARIT BUNTAR,                                              Nama Penyelia
PERAK DARUL RIDZUAN.

Tarikh :        29 JUN 2007                              Tarikh :   29 JUN 2007

CATATAN : * Potong yang tidak berkenaan.
          ** Jika Tesis ini SULIT atau TERHAD, sila lampirkan surat daripada pihak
             berkuasa/organisasi berkenaan dengan menyatakan sekali tempoh tesis ini perlu
             dikelaskan sebagai SULIT atau TERHAD
          ? Tesis dimaksudkan sebagai tesis bagi Ijazah Doktor Falsafah dan Sarjana secara
             penyelidikan, atau disertasi bagi pengajian secara kerja kursus dan penyelidikan,
             atau Laporan Projek Sarjana Muda (PSM).
                                                                        29 June 2007


Librarian
Perpustakaan Sultanah Zanariah,
UTM Skudai,
Johor Darul Takzim.


Sir,


               CLASSIFICATION OF THESIS AS RESTRICTED


  DEGRADATION OF PALM OIL MILL SECONDARY EFFLUENT (POMSE)
                               USING BIOSTRUCTURE
                      NURUL BAHIYAH BINTI ABD WAHID


Please be inform that the above mentioned thesis entitled “DEGRADATION OF
PALM OIL MILL SECONDARY EFFLUENT (POMSE) USING
BIOSTRUCTURE” be classified as RESTRICTED for a period of three (3) years
from the date of this letter. The reasons of this classification are:


        i.     Commercialization of research product.
       ii.     Patent pending.




Thank You


Sincerely yours,


……………………….
(DR AZMI BIN ARIS)
Faculty of Civil Engineering,
UTM Skudai, Johor.
013-7467722
                                                                                      ii




“We declare that we have read through this project report and in our opinion this
project report is adequate in term of scope and quality for the purpose of awarding
   the degree of Master of Engineering (Civil- Environmental Management).”




           Signature                : …………………………….
           Name of Supervisor I     : DR AZMI BIN ARIS
           Date                     : 29 JUNE 2007


           Signature                : …………………………….
           Name of Supervisor II : PM DR ZAHARAH IBRAHIM
           Date                     : 29 JUNE 2007


           Signature                : ……………………………..
           Name of Supervisor III : DR ZAITON A. MAJID
           Date                     : 29 JUNE 2007
                                                                                      ii




“I declare that this project report entitled “Degradation of Palm Oil Mill Secondary
Effluent (POMSE) Using Biostructure” is the result of my own research except as
cited in the references. The report has not been accepted for any degree and is not
                   concurrently candidate of any other degree.”




            Signature        : ……………………………
            Name             : NURUL BAHIYAH BINTI ABD WAHID
            Date             : 29 JUNE 2007
iii
                                                                                    iv




                             ACKNOWLEDGEMENTS




       I would like to express my sincere gratefulness to Allah S.W.T for giving me
wisdom and strength in my project work. Deepest appreciation to my supervisor and
co supervisors: Dr Azmi Aris, Dr Zaharah Ibrahim and Dr Zaiton A.Majid for giving
me support and guidance throughout this project.


       Greatest appreciation to my family especially my mother and my late father
who gave me full support in completing this project. I am also grateful to all the lab
staff especially Puan Rosmawati, Pak Usop and En Ramlee for their kindness,
guidance and sharing their experience with me. Also deepest thanks to research
assistants from Department of Biology especially Miss Nadirah, Saiful Zaini, Zaini,
Azrimi, Izza and Fareh who help me in doing research on biological aspects. Also
special thanks to PhD students, Pn Khalida Muda, En Zulkifli and Miss Nurmin for
their guidance and advice.


       Lastly, I would like to thank my fellow friends for their help, encouragement,
inspiration and support in completing this study.
                                                                                     v




                                    ABSTRACT




       Biostructure treatment is one of the latest biotechnology applications in
environmental engineering. In this study, the biostructure treatment was used to treat
the palm oil mill secondary effluent (POMSE). Biostructure is comprised of cement,
aggregates, sand, zeolite, lightweight aggregates, granular activated carbon (GAC),
water and microorganisms. In this study, biofilm was developed to increase the
biostructure’s performance. Seven types of microbes were used consist of microbe
A, B, C, S1, S2, ADL1 and ADL2, which were isolated from textile wastewater, Sg
Segget and fermented food.       The microorganisms grew on the surface of the
biostructure in the form of biofilm and degrade the waste, hence treating the
POMSE. The three reactors that were used to treat POMSE in this study comprised
of reactor A (10 biostructures), reactor B (5 biostructures) and reactor C (without
biostructure) that acted as a control. Results obtained showed that 10 biostructures in
the 5-liter batch reactor gave the average removal of colour of 51%, COD of 42%,
TOC of 42% and SS of 80% in 4 days HRT, whereas 5 biostructures able to remove
48% colour, 37% COD, 35% TOC and 70% SS. The results showed that the
efficiencies of the biostructure treatment depend on the surface area of biostructures
and the retention time. More biostructures resulted in higher degradation of POMSE.
From the survivability test, only three out of seven microbes developed at the early
stage of biofilm development survived at the end of the experiments, namely microbe
A, B and ADL1. It can be concluded that biostructure treatment is a viable polishing
treatment of POMSE before being discharged into the river.
                                                                                     vi




                                     ABSTRAK




       Biostruktur adalah salah satu aplikasi bioteknologi terkini dalam kejuruteraan
alam sekitar. Di dalam kajian ini, biostruktur telah digunakan untuk merawat air sisa
sekunder dari kilang kelapa sawit. Biostruktur dihasilkan daripada campuran simen,
aggregat, pasir, zeolite, aggregat ringan, karbon teraktif, air dan campuran
mikroorganisma.     Dalam kajian ini, biofilem telah dibentuk bagi meningkatkan
keberkesanan biostruktur. Tujuh jenis mikrob telah digunakan iaitu mikrob A, B, C,
S1, S2, ADL1 dan ADL2, yang telah dipencilkan dari air sisa tekstil, Sungai Segget
dan sumber makanan tertapai. Mikroorganisma hidup pada permukaan biostruktur
dalam bentuk biofilem dan mendegradasi, seterusnya merawat airsisa tersebut. Tiga
reaktor telah digunakan dalam kajian ini iaitu reaktor A (10 biostruktur), reaktor B (5
biostruktur) dan reaktor C (tanpa biostruktur) sebagai kawalan. Keputusan ujikaji
mendapati bahawa 10 biostruktur di dalam 5 liter sampel telah menghasilkan peratus
pengurangan sehingga 51% penyahwarnaan, 42% COD, 42% TOC dan 80% pepejal
terampai dalam 4 hari masa tahanan, manakala 5 biostruktur mampu mengurangkan
48% warna, 37% COD, 35% TOC dan 70% pepejal terampai dalam tempoh masa
yang sama.     Keputusan menunjukkan bahawa keberkesanan biostruktur adalah
bergantung kepada luas permukaannya dan masa tahanan. Lebih banyak biostruktur
yang digunakan memberikan lebih kemampuan degradasi terhadap airsisa tersebut.
Daripada ujian kebolehupayaan, hanya tiga daripada tujuh mikrob yang dibentuk
sebagai biofilem pada peringkat awal berupaya hidup sehingga ke akhir eksperimen,
iaitu mikrob A, B dan ADL1. Dapat disimpulkan bahawa biostruktur berupaya
menjadi salah satu teknik rawatan air sisa sekunder kilang kelapa sawit sebelum
dilepaskan ke sungai.
                                                     vii




                         TABLE OF CONTENTS




CHAPTER                             TITLE     PAGE


          THESIS STATUS DECLARATION LETTER
          SUPERVISOR’S CERTIFICATION
          TITLE                                 i
          DECLARATION                           ii
          DEDICATION                           iii
          ACKNOWLEDGEMENT                      vi
          ABSTRACT                              v
          ABSTRAK                              vi
          TABLE OF CONTENTS                    vii
          LIST OF TABLES                       xi
          LIST OF FIGURES                      xii
          LIST OF ABBREVIATIONS/TERMS          xiii
          LIST OF APPENDICES                   xiv




I         INTRODUCTION                          1
          1.1   Introduction                    1
          1.2   Problem Statement               2
          1.3   Aim and Objectives of Study     3
          1.4   Scope of Study                  4
                                                                     viii



II    LITERATURE REVIEW                                             5
      2.1   Introduction                                            5
      2.2   Palm Oil Industry Background                            5
      2.3   Palm Oil Mill Effluent Characteristics                  7
      2.4   Technology of Palm Oil Mill Effluent Treatment          8
            2.4.1    Pre treatment of Palm Oil Mill Effluent        8
            2.4.2    Aeration System                                9
            2.4.3    Aerobic and Anaerobic Treatment                10
            2.4.4    Membrane Treatment System                      10
            2.4.5    Fenton System                                  11
      2.5   Colour Removal of Palm Oil Mill Effluent                11
      2.6   Introduction to Biotechnology Applications              12
            2.6.1    Biostructure Treatment                         13
            2.6.2    Biofilm                                        13
            2.6.3    Advantages and Disadvantages                   14
            2.6.4    Microorganisms                                 14
            2.6.5    Composition of Biostructure                    16
                     2.6.5.1 Cement                                 17
                     2.6.5.2 Aggregates                             17
                     2.6.5.3 Water                                  17
                     2.6.5.4 Lightweight aggregates, GAC, Zeolite   17
      2.7   Previous Studies on Biostructure and Bio Block          18
            2.7.1    Eco Bio Block                                  18
            2.7.2    Industrial Wastewater                          19
            2.7.3    River and Domestic Wastewater                  20




III   METHODOLOGY                                                   21
      3.1   Development of Biostructure                             21
            3.1.1    Preparation of Growth Medium                   21
            3.1.2    Preparation of Cell Suspension                 22
                                                                      ix

           3.1.3    Basic Components                             22
           3.1.4    Mixing Process                               23
           3.1.5    Mould Preparation and Curing                 24
     3.2   Development of Biofilm                                26
     3.3   Analytical Method                                     26
           3.3.1    Chemical Oxygen Demand and Colour            27
           3.3.2    Total Organic Carbon                         28
     3.4   Experimental Procedures                               29
     3.5   Test for Survivability of Bacteria                    30
           3.5.1    Colony Morphology                            31
           3.5.2    Simple Staining                              31




IV   RESULTS AND DISCUSSIONS                                     32
     4.1   Introduction                                          32
     4.2   Characteristics of Palm Oil Mill Secondary Effluent   32
     4.3   Degradation of Palm Oil Mill Secondary Effluent       33
           4.3.1    Colour Removal                               33
           4.3.2    Chemical Oxygen Demand Removal               36
           4.3.3    Total Organic Carbon Removal                 38
           4.3.4    Dissolved Oxygen Profile                     39
           4.3.5    Suspended Solid Removal                      40
     4.4   Survivability of Bioaugmented Bacteria                42
           4.4.1    Morphology of Bacteria                       42
           4.4.2    Viable Count                                 44
           4.4.3    Simple Staining                              46
                                             x



V   CONCLUSIONS AND RECOMMENDATIONS     48
    5.1   Conclusions                   48
    5.2   Recommendations               49




    REFERENCES                          50


    APPENDICES                        55 - 64
                                                               xi




                         LIST OF TABLES




TABLE                          TITLE                    PAGE


 2.1    Standard Discharge Limit by the Department of    7
        Environment Malaysia
 2.2    General Characteristics of Raw POME              8
 3.1    Sources and Functions of Microorganisms Used     22
 3.2    Chemical Composition of Cement                   23
 3.3    The Mix Proportions for 12 Biostructures         24
 4.1    Characteristics of POMSE before Treatment        33
 4.2    Bacterial Morphologies                           42
 4.3    Viable Count Results                             44
                                                                              xii




                             LIST OF FIGURES




FIGURE                               TITLE                             PAGE
  2.1    Process of Palm Oil Industry                                   6
  2.2    Bacterial Growth Curve                                         15
  2.3    Typical Shapes of Bacteria                                     16
  2.4    Various Types of EBB                                           18
  3.1    The Processes of Biostucture Development                       25
  3.2    Biostructure: (a) without biofilm, (b) with biofilm            26
  3.3    Hach DR4000U Spectrophotometer                                 27
  3.4    Shimadzu TOC Analyser VCSH                                     28
  3.5    Batch Reactors set up. (a) Reactor A: 10 Biostructures, (b)    29
         Reactor B: 5 Biostructure and (c) Reactor C: Control
  3.6    Crushed Biostructure in Saline                                 30
  3.7    Equipments Used in Viable Count Process: (a) Incubator,        30
         (b) Colony Counter
  4.1    Profile of Colour Removal                                      34
  4.2    Colour Removal in Reactor A after 96 hours HRT                 35
  4.3    Profile of COD Removal                                         37
  4.4    Profile of TOC Removal for Cycle 1                             38
  4.5    Profile of DO for Cycle 1                                      39
  4.6    Profile of Suspended Solid Removal                             40
  4.7    Suspended Solid after 96 hours HRT                             41
  4.8    Colonies of Bacteria on Plate                                  45
  4.9    Examples of Indigenous Microbe Found in POMSE                  45
 4.10    Simple Stain (400 x magnification)                             46
                                               xiii




        LIST OF ABBREVIATIONS/ TERMS




ADMI     American Dye Manufacturer Institute
APHA     American Public Health Association
BOD      Biochemical Oxygen Demand
COD      Chemical Oxygen Demand
DO       Dissolved Oxygen
DOE      Department of Environment
EQA      Environmental Quality Act
FFB      Fresh Fruit Brunch
GAC      Granular Activated Carbon
HRT      Hydraulic Retention Time
POME     Palm Oil Mill Effluent
POMSE    Palm Oil Mill Secondary Effluent
SS       Suspended Solid
TOC      Total Organic Carbon
                                                       xiv




                    LIST OF APPENDICES




APPENDIX                          TITLE          PAGE


   A       Data of Colour with Time               55
   B       Data of COD with Time                  57
   C       Data of TOC with Time                  59
   D       Data of SS with Time                   60
   E       Optical Density and Cell Dry Weight    62
   F       Equipments Used in the Experiment      63
                                    CHAPTER I




                                 INTRODUCTION




1.1    Introduction


       Palm oil is one of the important industrial sectors in Malaysia. Every single
year, the production of palm oil increased rapidly (Wah et al., 2002). In 1998,
Malaysia had produced 7,425,000 tonnes of palm oil for worldwide export, while in
2001, the amount of crude palm oil production increased to 985,063 tonnes per
month which contributed to total amount of more than 12 millions tonnes in a year
(Palm Oil Link, 2001).


       The palm oil sector contributes significantly to the economy of Malaysia. It
accounts for approximately 2.93% or RM6.4 billion of the gross domestic
productivity of Malaysia in 2002. Providing a yield of 10 times more than most of
the other oil crops, oil palm is the most efficient in land and resource utilization and
contributing effectively to sustainable development (NVT, 2003).



       As the production of palm oil increased, more palm oil mill effluent (POME)
is generated annually. Currently about 3.0 million hectares of land are under palm
oil cultivation with 300 palm oil mills processing the fresh fruit bunches of palm.
The total annual quantity of wastewater generated is estimated to be 1.8×106m3
                                                                                       2

(Ahmad et al., 2003). This situation contributed to more study on the technology of
treatment of the POME, due to the large amount of water needed for palm oil mill
extraction and the discharge of partially treated effluent into public watercourses.



       Palm oil mill effluent is extremely rich in organic content that needs to be
properly treated before discharge into rivers. It contains lignocellulosic wastes with
a mixture of carbohydrates and oil.          Chemical oxygen demand (COD) and
biochemical oxygen demand (BOD) of POME are very high (Oswal et al., 2002).
Incomplete extraction of palm oil from the palm nut might increase COD values
substantially.


       The palm oil industry should now look beyond their obligation to comply
with the requirements of Environmental Quality Act 1974 in the management of
POME. The future growth of the industry sector will require further enhancement in
their environmental management practices and in advancing their social and
sustainability development responsibility.      Appropriate technologies are rapidly
evolving in the local scene to meet the demands of the industry.


       In Malaysia, the Department of Environment (DOE) has enforced the
regulation for the discharge of effluent from the crude palm oil industry. The
regulations are based on the Environmental Quality (Prescribed Premises) (Crude
Palm Oil) Order and Regulations 1977.




1.2    Problem Statement


       Nowadays, Malaysia is currently the largest producer and exporter of palm
oil. The implication of this scenario, Malaysia has to play important role in fulfill the
needs of palm oil industry. In the processing of palm oil fruit, large quantities of
wastewater are generated from the sterilization and oil clarification sections. Raw
palm oil mill effluent comprises of water-soluble components of the palm fruits as
well as some suspended materials like palm fibre and oil. These components are
                                                                                       3

non-toxic in nature (Golden Hope, 2004). However, palm oil mill effluent cannot be
discharged into the watercourse directly. The effluent must be treated to acceptable
quality before it can be discharged into the watercourse for land application.


             Recently, various treatment processes have been designed to encounter the
problem issued from POME. Biological treatment is the commonly used method as
POME has high organic content which can be degraded by microorganisms (Kon,
2006). However, the application of biological processes is normally incapable of
complying with the standard requirements set by the regulator (Ooi, 2006). In
addition, the treated POME is still coloured and contains high concentration of non-
biodegradable organics which requires further treatment.


             In this study, biostructure treatment technology was used as a polishing
treatment for palm oil mill secondary effluent (POMSE). This technology involved
the application of selected microorganisms to improve the quality of the effluent.
biostructure was formulated through a stringent process of mixing the precise amount
of cement, sand small aggregates and environmental friendly microorganisms
(Azhar, 2006). This method is one of the latest microbial technologies used in
environmental engineering.




1.3          Aim and Objectives of Study


             The aim of this study was to develop an economical polishing treatment of
POMSE that fulfills the standard in the regulation. The objectives of the study were:
        i.          To investigate the feasibility of biostructure in degradation of
                    POMSE;
       ii.          To determine the effects of the gross surface area of biostructure in
                    the treatment process; and
      iii.          To determine the role of the bioaugmented bacteria and their
                    survivability on the biostructure.
                                                                                    4

1.4          Scope of Study


             This study comprises of a series of laboratory scale experiment. POMSE
from a palm oil mill in Kulai, Johor was used. This study covered:
        i.         Development of biostructure at laboratory scale using the basic
                   component of concrete with the addition of zeolite, lightweight
                   aggregates and granular activated carbon (GAC);
       ii.         Development of biofilm on the biostructure surface:
      iii.         Three laboratory scale reactors were developed for the treatment of
                   POMSE; and
      iv.          Sampling and analysis of colour, COD, total organic carbon (TOC),
                   suspended solid (SS) and viable count of bacteria.
                                    CHAPTER II




                              LITERATURE REVIEW




2.1    Introduction


       The industry of palm oil is facing serious challenges to meet the
environmental regulations stated by government. Besides earning a high profit, palm
oil processing mills discharge a large amount of effluent (Ahmad et al., 2005).
Without proper treatment, this wastewater will pollute the watercourses.


       Palm oil mill effluent contains ‘lignocellulosic’ wastes with a spectrum of
carbohydrates, a range of nitrogenous compounds, free organic acids and an
assembly of minor organic and mineral constituents (Marttinen et al., 2003).
Released into rivers without treatment, this viscous brown sludge would choke
aquatic life and pollute water supplies.




2.2    Palm Oil Industry Background


       In the early 1970s, Malaysia's economic development was based on the
agricultural sector. Large areas of forest were converted into oil palm estates. By
the end 1980s, the oil palm estate covered one third of the country's cultivated area.
                                                                                           6

As a result of expansion in oil palm based industry, during 1975-1985, crude palm
oil production rose from 1.3 million tones to 4.1 million tones making it the country
second largest earner of foreign exchange by 1984 (ESCAP, 2005). Figure 2.1
shows the processes involved in palm oil industry.



     Bunch Reception



           Bunch
        Sterilization



     Bunch Threshing
                                               Empty Bunch


      Fruit Digestion



       Pulp Pressing                                   Nut Recovery

                              Nut and Fibre
      Oil Clarification                                  Nut Drying



        Oil Drying                                      Nut Cracking



        Oil Packing                                   Kernel Separation
                                                                                  Shells


                                                       Kernel Storage



             Figure 2.1: Process of Palm Oil Industry (FAO Corporate Document
                                 Repository, 2004).




       With the growth of agro based industries, the palm oil related industries
become a major pollution problem. By 1970s, 42 rivers in Malaysia were severely
aerobically polluted by untreated effluents (ESCAP, 2005).              Consequently, this
                                                                                      7

situation led to significant impacts on coastal areas and rivers, which in turn affected
the socio-economy of the local communities. The industry has made tremendous
strides towards the treatment of liquid effluents since 1977 till now. A variety of
processes are now available for the treatment of the liquid waste.


       In 2004, more than 40 million tonnes of POME was generated from 372 mills
in Malaysia (Hassan et al., 2004). In order to prevent pollution from this effluent,
POME has to be treated to fulfill a few characteristics as which have been stated by
Department of Environment Malaysia. The respective standard for discharge limit is
shown in Table 2.1.




 Table 2.1: Standard Discharge Limit by the Department of Environment Malaysia
                                     (DOE)
                        Parameters                        Limits
                       BOD3, (mg/L)                         100
                 Suspended solids (mg/L)                    400
                   Oil and grease (mg/L)                    50
               Ammonical nitrogen (mg/L)                    150
                   Total nitrogen (mg/L)                    200
                           pH                            5.0 – 9.0
                      Temperature (C)                       45




2.3    Palm Oil Mill Effluent Characteristics


       The raw POME has extremely high content of degradable organic matter,
which is due in part to the presence of unrecovered palm oil. Fresh POME is a
colloidal suspension containing 95-96% water, 0.6-0.7% oil and 2-4% suspended
solids that are mainly debris from palm fruit mesocarp generated from three sources
which are sterilizer condensate, separator sludge and hydrocyclone (Ahmad et al.,
2005). The general characteristics of raw POME are shown in Table 2.2.
                                                                                  8

       Table 2.2: General Characteristics of Raw POME (Hassan et al., 2004)

                       Parameter                              POME

      pH                                                     3.4 - 5.2
      Biochemical oxygen demand (BOD)                    10,250 – 43,750
       Chemical oxygen demand (COD)                      15,000 – 100,000
       Suspended solids                                   5,000 – 54,000
       Ammonical nitrogen                                     4 - 80
       Total nitrogen                                       180 – 1,400
       Oil and grease                                      150 – 18,000
      *all unit in mg/L except for pH.




2.4     Technology of Palm Oil Mill Effluent Treatment


        Recently, various treatment processes have been designed to encounter the
problem issued from the POME. The Malaysian palm oil industry has applied
various effluent treatment technology which are anaerobic and facultative ponds,
tank digestion and mechanical aeration, tank digestion and facultative ponds,
decanter and facultative ponds and physico-chemical and biological treatment
(Krishnan et al., 2006).




2.4.1 Pre treatment of Palm Oil Mill Effluent


        According to Ahmad et al., (2003), flocculation, extraction, adsorption and
membrane separation can remove suspended solid and residual oil from POME
effectively. In this case, membrane separation was applied to remove any residual
suspended solids and oil remaining after the pretreatments. The treatment efficiency
of the processes was measured as percentage removal of suspended solids and oil
respectively. For flocculation, the optimum performance was achieved using 4,000
mgdm-3 of alum and mixer speed of 150 rpm for one hour. At these conditions, the
turbidity was decreased from 14,080 NTU to 983 NTU.          It was found that the
                                                                                       9

solvent extraction process gave a 95% reduction in residual oil as compared with
88% obtained using the adsorption process. From the findings, it showed that
membrane separation technology is a better treatment technology in terms of water
recovery and its recycling (Ahmad et al., 2003).


       Bhatia, (2006), had covered the suitability of the coagulation–flocculation
process using Moringa oleifera seeds after oil extraction as a natural and
environmentally friendly coagulant for POME treatment.            The performance of
Moringa oleifera coagulant was studied along with the flocculant in removal of SS,
organic components and increasement of the floc size.


       The optimum values of the operating parameters obtained from the laboratory
jar test were applied in a pilot-scale treatment plant. Pilot-scale pretreatment resulted
to 99.7% suspended solids removal, 71.5% COD reduction, 68.2% BOD reduction,
100% oil and grease removal and 91% TKN removal.




2.4.2 Aeration System


       Aeration is one of the effluent treatment processes where water and air were
in contact with one another to supply dissolved oxygen (DO) to the microorganisms.
Hui, (2005), had conducted a study based on the different method of aeration in
POME treatment. For this study, three types of aeration system were used which are
Diffused Air (DA), Oxygen Enriched Air (OEA) and Pure Oxygen (PO).                   The
oxygen purity for PO is 100%, OEA about 35% and followed by DA 20.9%. The
findings showed that the higher purity oxygen, the DO in POME will increase. The
PO aeration able to remove 88.1% of BOD, followed by OEA 63.7% and DA 62.9%
BOD removal (Hui, 2005).
                                                                                10



2.4.3 Aerobic and Anaerobic Treatment


       Modified Upflow Anaerobic Sludge Blanket (UASB) using modulated palm
fibre as a fixed bed is an alternative way to treat POME. A study was conducted to
determine the organic and nutrient removal convincing fixed bed reactor and upflow
design (Jini, 2006). The variables tested were concentration of COD, phosphorus,
ammoniacal nitrogen, and reduction of TSS and VSS. From the results, it showed
that shorter anaerobic period was appropriate for ammonia removal due to
nitrification process, while COD and PO4 removal was significantly removed under
longer period and larger dilution factor. The most relevant organic reduction rate
was at 4 hours HRT.


       According to Zinatizadeh et al., (2005), anaerobic treatment is the most
suitable method for the treatment of effluents containing high concentration of
organic carbon. Anaerobic treatment using up-flow anaerobic sludge fixed film
(UASFF) reactor shows the good result which can reduce 95% of COD at an average
organic loading rate (OLR) of 15 g COD/L/day. COD removal of 96% was obtained
at an OLR of 10.6 g COD/L/day with hydraulic retention time (HRT) of 4 days.


       According to the study done by Vijayaraghavan et al., (2006), treatment of
POME was investigated using aerobic oxidation based on an activated sludge
process. The efficiency of the activated sludge process was evaluated by treating
digested and diluted raw POME anaerobically. As a result, it showed that at the end
of 36 hours of HRT, the highest COD removal efficiency was 83%, whereas at 24
hours HRT, the percentage removal of COD was 57%.




2.4.4 Membrane Treatment System


       Membrane technology is viewed to be more beneficial in treating POME.
There are many membrane process applications in water and wastewater treatment
that have been proven to be efficient. Membrane technology covers a large spectrum

								
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