Pal oil mill machines

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Machineries and their problems in Palm Oil Mill

Transcript of Pal oil mill machines

  • 1. Chronology of Operational ChallengesItemChallenges Root CauseReference 1 Furnace no draftLow ash melting point of EFB fibers 1. Faxes from Hartalega to Vyncke, Combustion chamber is kept The inherent property of low ash referenceconstantly underpressure to avoid melting point of EFB fibers resulteda. H.A.-Vync-KML-43explosion or leakage of flame toin formation of soft and sticky b. H.A.-Vync-KML-44outside of the chamber. ashes.c. H.A.-Vync-KML-46 This underpressure is created by a These soft and sticky ashes formed d. H.A.-Vync-KML-51large suction fan mounted. before adhere to the thermal oil coils, hotthe chimney. Between thewater economisors and dust collector 2. Faxes from Vyncke to Hartalega,combustion chamber and suction fanblocking the travel path hot gases. referenceare thermal oil coils and dust Therefore pressure of thea. 1.2549 dated 20.08.2003collectors where the hot gasescombustion chamber increases. b. 1.2549 dated 02.09.2003produced from the combustionchamber would to pass through.3. Figures 1, 2, 3, and 4 The combustion chamber draft ismonitored real time by a pressuresensor. The plant stops whenevercombustion chambers pressure goesto positive (no vacuum). We experienced frequently furnaceno draft situation that resulted instoppage of the plant. 2 Excessive clinker formation Low ash melting point of EFB fibers1. Faxes from Hartalega to Vyncke, Excessive clinkers were formed on A softened / melted ash due to thereferencethe furnace (combustion chamber low melting point property of emptya. H.A.-Vync-KML-43side wall), furnace floor (step grate)fruit bunches and its high potassium b. H.A.-Vync-KML-44and at the furnace ceiling. content resulted in formation of hardc. H.A.-Vync-KML-46silica like clinker on the mentioned d. H.A.-Vync-KML-49 Damaged furnace refractory wallsurfaces.e. H.A.-Vync-KML-51 Accumulation of clinker resulted in

2. collapse of refractory lining of2. Fax from Vyncke to Hartalega,furnace side wall and furnacereference 1.2549 dated 02.09.2003ceiling.3. Purchase order no. to replace (overhaul) old refractory with newa. 041999b. 040225c. 042141d. 042127e. 042129f. 042473g. 0423094. Figures 5, 6, 7 and 83 High furnace temperature Low calorific value of EFB fibers1. Fax from Hartalega to Vyncke, Frequent occurrence of high furnace Owing to this characteristic, reference H.A.-Vync-KML-51 temperature. equipment in the plant such as A temperature sensor senses the thermal oil coil and combustion furnace temperature continually. chamber are undersized Once temperature reaches the limit, To compensate for the reduced the system will cut off to prevent surface area of these equipment (due over-temperature situation.to undersizing), the operating Over temperature may results in temperature has to be higher in order melt down of the furnace and greatly to attain the required capacity shortens the lifespan of the plant. Operating in higher temperature also Hence the necessity of the safety cutresulted in other problems off to prevent over-temperature. mentioned earlier such as clinkerformation due to melting ashes andblockage of pathway of hot gases.4 Over estimation of fuel density Low density of EFB fibers 1. Faxes from Hartalega to Vyncke, Owing to the fact that EFB fibers are EFB fibers were assumed to havereference 3. a relatively new biomass fuel,density of 250 kg/m3 a. H.A.-Vync-KML-46 therefore its properties are not well Actual density was found to be b. H.A.-Vync-KML-49 established.around 105 kg/m3 The density of EFB fibers were2. Faxes from Vyncke to Hartalega, wrongly estimated by Vyncke, reference resulting in undersizing of the a. 1.2549 dated 20.08.2003 feeding systems b. 1.2549 dated 02.09.2003 Therefore feeding conveyors speedsc. 1.2549 dated 09.09.2003 were increased to accommodate the undersize condition, resulting in 3. Figures 9, 10, 11, and 12 much higher wear and tear.5 Damaged moving floor (ESB) Abrasive property of EFB fibers 1. Faxes from Hartalega to Vyncke, Moving floor is a fuel feeding Owing to the highly abrasive referece system that installed at floor level.property of the EFB fibers, the a. H.A.-Vync-KML-49 This system consists of 3 to 4welding joints of the moving floorb. H.A.-Vync-KML-51 ladders, each ladder moving back that were in direct contact with the and forth in a horizontal directionEFB fibers were grinded of,2. Faxes from Vyncke to Hartalega, parallel to the floorresulting in breakages. referece Its function is to discharge biomassa. 1.2549 dated 09.09.2003 materials into feeding screws toEntanglement of EFB fibers b. 1.2549 dated 13.10.2003 convey fuel to the combustion EFB fibers tend to entangle, making chamber. this material difficult to convey by 3. Figures 11 and 12 Moving floor (ESB) for EFB fibers the moving floor. encountered extremely high wear Some modifications were carried out 4. Purchase order no. 037770 to and tear and was also unable tobut were unsuccessful, instead lead purchase new moving floor function wellto further damages to the moving A new moving floor was purchasedfloor. after only running the plant for 18 months6 Over current of screw conveyorsAbrasive property of EFB fibers 1. Faxes from Hartalega to Vyncke, Motors of screw conveyors Owing to the highly abrasive referece conveying EFB fibers frequentlyproperty of the EFB fibers, screw a. H.A.-Vync-KML-57 4. experienced over current.conveyors experience high wear andb. H.A.-Vync-KML-58 tear Breakage of screw conveyors2. Figures 9 and 10 Screw conveyors broke not long Entanglement of EFB fibersafter plant started operation EFB fibers tend to entangle, making 3. Purchase order no. for repair of this material difficult to convey byscrew conveyor Breakage of silo mixerthe screw conveyors.a. 030048 Mixer is installed at the intermediate When EFB fibers are entangled, b. 041288silo forces resisting the screw conveyorsc. 041499 are much increased resulting in overd. 040998 current and breakages. Due also to entanglement, silo mixer4. Purchase order no.030076 to replace experience high forces that results insilo mixer high wear and tear and short fatigue cycle7 Damaged impeller of flue gas fanImpermeability of EFB fibers1. Fax from Hartalega to Vyncke, Flue gas fan impeller welding joints Due to impermeability of the EFB referece H.A.-Vync-KML-60crackedfibers, primary and secondary air Flue gas fan impellers wereflows were increased to provide2. Figures 13 and 14noticeably thinner within less thanmore air for combustion.12 months in operations Increase in primary and secondary 3. Purchase order no. for purchase of air flows have to be compensated by new flue gas fan impeller increasing the speed of the flue gas a. 031117 fan (suction fan installed before theb. 040699 chimney) to maintain a negativec. 041781 pressure inside the combustion chamber.Highly abrasive property of EFB fibers Due to high ash and potassium content of EFB fibers, the flue gas fan impeller where the air flow 5. speed is the highest experiencedhigh wear and tearHigh operating temperature Due to the plant being undersized because of unanticipated problems associated with EFB fibers as biomass fuel, the thermal oil heaters were forced to run at higher temperature in order to achieve its design capacity. This has resulted in accelerated deterioration of parts8 Biomass boilers 1&2 unable to deliverFurnace no draft1. Faxes from Hartalega to Vyncke,up to the design capacity Flue gas fan impeller speed has to bereference All the above has resulted in the increased to increase the furnace a. H.A.-Vync-KML-51boilers 1 and 2 unable to deliver heatunderpressure to compensate for the b. H.A.-Vync-KML-54energy up to the design capacityincrease in primary and secondary Designed capacity 15Gcal/hr air flows due to impermeability of 2. Email from Vyncke to Hartalegathe EFB fibers. From Jef Mestdagh to Kuan Mun This has resulted in reduced Leong dated 24.12.2003retention time of hot gases within thesystem, therefore reducing the time3. Contract signed between Vynckeof heat transfer to the thermal oil and HartalegaExcessive clinker formation Excessive clinkers were formed due to the low ash softening point of EFB fibers. Its furnace design temperature of 1,000C is not sustainable as excessive clinker will form 6. High furnace temperature To deliver the designed capacity, theboilers need to be forced to run atextremely high temperature (furnacetemperature above 1,100C. At such high temperature, the risk ofthe system cutting off is high as thecut off limit is 1,200C. Over-estimation of fuel density Due to over estimation of density ofEFB fibers, all feeding systems areunder-sized. Tuning up their operating speed willincrease wear and tear, not a goodengineering practice. Sticky ashes Build up of soot and sticky ashes around thermal oil coils, creating an insulating layer and therefore reducing heat exchanging surface. Plant has to be stopped frequently to clean of the soot9 Damaged Soot BlowersAbrasive nature of EFB fibers1. Figures 15 and 16 Soot blowers are installed to use Owing to the abrasive nature of EFBcompress air to blow away soot fiber and its high ash content, theformed on the outer surface of the soot blowers have higher wear andthermal oil coils. tear rate. These soot blowers experienced highwear and tear 7. 10 Damaged multicyclonesAbrasive nature of EFB fibers1. Purchase order no. 039586 for A dust collector installed between Owing to the abrasive nature of EFB replacement of cyclones the thermal oil coil and flue gas fanfiber and its high ash content, the to collect dust / soot beforededustor and cyclones have higher wear 2. Purchase order no. 040792 to repair discharging out through the chimneyand tear rate.dedustor Within the dust collector, there are multi-cyclones, these cyclones experienced high wear and tearPHOTOGRAPHSBlocked cycloneCyclone not Soot formationblockedFigure 1: Softened ashes sticking to the thermal oil coilsFigure 2: