Perhitungan waktu resistensi CST (continous settling tank)

Prediksi  Waktu Retensi di Vertical Clarifier Tank .

Waktu retensi adalah waktu tinggal cairan atau massa dalam suatu wadah bervolume tertentu dan dinyatakan dalam satuan waktu.

Waktu Retensi yang diharapkan min 4 jam.

                             

Data dibutuhkan:

1.   Total Volume cairan dalam tangki Vertical Clarifier Tank.

2.   Kapasitas Pabrik(TpH)

3.   %OER aktual

4.   Oil in crude aktual

5.   Laju light phase ke Vertical Clarifier Tank.

                                       

Volume Cylinder = V1=  ¼. π .d² . h₁

Volume kerucut = V2 = ¹/₁₂. π .d²  . h₂

Total = V₁ + V₂ = Volume Total Cairan (m³)

Note:

Untuk mempermudah perhitungan, volume cairan dibawah pipa underflow 

dimasukkan dalam perhitungan volume cairan

Jenis- jenis Decanter dan fungsinya

Kesulitan yang dialami dalam pengolahan sludge terutama dalam mekanisme pengoperasian Sludge Separator dan penggantian Nozzle, maka dipikirkan cara pemisahan lumpur yang lebih efektif. Cara pemisahan lumpur dalam Sludge Separator adalah putaran horizontal dan vertikal, maka  decanter (40) adalah sejenis separator dengan posisi horizontal memanjang dengan jenis putaran vertikal..

Decanter dapat menggantikan unit-unit pengolahan di Stasiun klarifikasi Desander, Sand Cyclone, Sludge Centrifuge dan Oil Purifier.

Keberhasilan dalam pengoperasian Decanter dipengaruhi oleh :

a.      Komposisi umpan yang akan diolah, karena ratio antara minyak, air dan lumpur mempengaruhi terhadap daya pisah alat tersebut.

b.      Fungsi alat Decanter tersebut.

c.      Perimbangan kapasitas alat dengan jumlah Sludge yang diolah.

1.      Jenis Decanter

Alat Decanter yang digunakan ada dua jenis yaitu berdasarkan keluaran yaitu

Komposisi Continous Setling Tank

komposisi pada CST

Keterangan	Umpan CST dari COT	Under Flow	Overflow
Minyak (%)	38	9	28
Emulsi (%)	10	10	56
Air      (%)	21	40	15,5
Sludge (%)	29	40	0,5
Pasir   (%)	2	1	0

Prosedur pengoperasian unit Continous Settling Tank ( CST)

Sebelum start proses lakukan pemeriksaan terhadap valve steam coil, agitator dan lakukan drain terhadap lumpur ± 3m³

1. Start proses

·         Buka Valve Steam coil ke CST

·         Hidupkan motor agitator

·         Hidupkan motor umpan CST dari COT

2. Saat proses

•      Pengecekan ketinggian minyak dengan ketebalan oil  25 – 30 cm.

•      Kontrol temperatur terjaga 90-95⁰C pada CST.

•      Pastikan steam trap berfungsi dengan baik.

3. Stop proseshttp://intisawit.blogspot.com/

•      Tutup pipa-pipa steam, valve

•      Matikan motor agitator.

•      Matikan pompa umpan dari COT.

•      Naikkan posisi oil skimmer dan sludge skimmer dan pastikan tidak ada aliran minyak ataupun sludge ke oil tank maupun ke sludge tank.

Metode pemisahan minyak kelapa sawit

Metode pemisahan minyak dari minyak kasar

            Ada beberapa cara yang lazim dilakukan dalam pemurnian minyak kasar dipabrik minyak kelapa sawit yaitu :

• Dengan cara pengendapan (settling)

Pemisahan minyak dari minyak kasar terjadi/berlangsung karena pengendapan bagian yang berat (slugde + air) dan minyak yang terpisah berada dilapisan atas

• Dengan cara pemusingan (centrifugal )

Dengan cara ini waktu pemisahan yang diperlukan menjadi lebih singkat karena bantuan tenaga centrifugal.

• Dengan cara pengaruh biologis

Cara ini adalah merupakan kelanjutan dari kedua cara tersebut diatas dan dilakukan pada proses pemisahan di fat-fit atau sludge oil recovery system.

Pada umumnya cara-cara tersebut diatas dilakukan secara tergabung : baik gabungan dari ketiganya maupun dua dari ketiga cara.http://intisawit.blogspot.com/

Tricanter

Tricanter is a tool to separate the oil (Light Phase), sludge (Heavy Phase) and solids (Solid) by means of centrifugal horizontal.
The way this is working Decanter sludge into the bowl with style sentripufal where the heavy specific gravity (solid) thrown kedinding bowl then taken by the scroll area to dry out toward the solid discarded conveyor. While the oil and sludge (water) that its density is lighter thrown stricken liquid (fluid). Then water and sludge is also separated based on its density, where oil (Light Phase) with a lighter specific gravity at the center will be at the center of the scroll or centrifugal force to the regulating tube so the oil will be cited and removed from Decanter with separate channels to the Reclaimed Oil Tank that there is next to the COT to be reprocessed while the water (Heavy phase) will be thrown on the outside of the scroll or bowl is on the wall and out through the regulating tube toward the heavy phase Sludge Recovery Tank (SRT).

Sludge tank

Sludge tank serves to accommodate the separation of Crude Oil Sludge from the CST while before treated or purified on a sand cyclone and Decanter. Sludge which is on CST tank sludge is applied to use the system under flow. In the sludge tank should also be kept temperatures 90 - 950C to allow the separation of sludge with oil in the next process easier and less susceptible to interference. The composition of the sludge from the existing CST on sludge tanks is as follows: - Oil: ± 9% - Emulsion: ± 10% - Water: ± 40% - Sludge: ± 40% - Sand: ± 1% Furthermore, the composition of the oil will be refined over the return on oil purifier and vacuum dryer. serves to accommodate the separation of Crude Oil Sludge from the CST while before treated or purified on a sand cyclone and Decanter. Sludge which is on CST tank sludge is applied to use the system under flow. In the sludge tank should also be kept temperatures 90 - 950C to allow the separation of sludge with oil in the next process easier and less susceptible to interference. The composition of the sludge from the existing CST on sludge tanks is as follows: - Oil: ± 9% - Emulsion: ± 10% - Water: ± 40% - Sludge: ± 40% - Sand: ± 1% Furthermore, the composition of the oil will be refined over the return on oil purifier and vacuum dryer.

Storage Tank

Storage Tank or piled tank is the storage of oil / CPO of the clarification prior to shipping / sent out, where the condition and quality of oil must be maintained during this storage process. During storage the oil temperature must be maintained 500-600 C because too high a temperature will cause the hygroscopic so easily oxidized, while the oil temperature too low can result in increases in FFA. Standards of quality oil production is expected in the storage tanks is as follows: - Levels of FFA: ± 3.50% - Moisture: 0.15% ± - Levels of Dirt: ± 0.02%

Vacuum Dryer

Vacuum Dryer is a means of drying oils by vacuum evaporation pressure minus 0.8 to 1 kg/cm2 (700 mmHg), the water content of the tool is expected to fall from 0.3% to 0.1%. This device consists of vacuum tubes and 3 (three) tinggkat steam ejectors steam generator which utilizes kevacuman  12 kg/cm2 pressure of the boiler, sprinkle the oil in through the nozzle into the tube and result kevaccuman then water vapor will evaporate and exploited by the steam ejectors 1 and condensed, the remaining steam from the steam ejector sucked by an ejector 2 and terkondensasiselanjutnya last remaining steam is sucked by the ejector 3 and discharged into the atmosphere. The water formed from steam ejector 1 and 2 directly accommodated in the hot water tank under the ejector (Hot Well Tank). While the oil is more difficult to evaporate will fall gets under vacuum tube will then be pumped into storage tanks.

Oil Purifier

This tool is often called the oil centrifuge, which serves to purify oils from dirt and water levels, where the water content of oil tanks ranged from 0.5 to 0.75% and impurities from 0.1 to 0.3%. This tool works by centrifugal force where the heavy oil with a lighter kind will be at the center of the instrument and pushed upwards by Paring disc while the dirt and water that the heavier weight of its kind will be on the outside of Paring disc, expected from the results of this process the water content can go down to 0.3 - 0.4% and 0.01% impurities and is a benchmark of success of an oil purifier.