Biodiesel Log

6/28/2004        Prepared mini-batches of biodiesel using 4.5 and 5.1gm lye per 1 liter oil           and 200 ml methanol

                        Good separation of biodiesel and glycerine layers with small soap layers

                        Also prepared mini-batches using ‘Fool Proof’ (two stage) method at 3.1                                              and 3.5gm lye per 1 liter oil and 200ml methanol

 

 

7/2/2004          Prepared mini-batches of biodiesel using 5.6 and 6.1 gm lye per 1 liter oil          and 200 ml methanol

                        Good separation of biodiesel and glycerine layers with small soap layers

                        Good separation of biodiesel and glycerine layers with moderate soap   layer for the 3.1gm and small soap layer for the 3.5gm mini-           batches

 

7/3/2004          Batch #1 – 1st Generation Processor

                        Using ‘Fool Proof’ method (two stage method)

                        55 gal of oil (no titration needed for this method)

                        Acidification step first, mix 60 minutes, let stand overnight

 

7/4/2004          Then base catalysis second (per procedure outlined by Kacs)

                        Let stand overnight

 

                        Mixed barrel of feedstock oil using paint mixer and cordless drill for 2-3                        minutes.  Took two 1 liter samples.

                        Prepared methoxide with 200ml Methanol and 6.6gr Lye and stirred with          stir bar on magnetic stirrer for 30min.

                        Prepared methoxide with 200ml Methanol and 6.3gr Lye and stirred with          hand swirling off/on for 30min.

                        Mixed methoxide (6.6gr Lye) with 1 liter oil for 5min and poured into    freshly cleaned jar.  Approx 2100.

                        Mixed methoxide (6.3gr Lye) with 1 liter oil for 5min and poured into    freshly cleaned jar.  Approx 2115

                        Let stand overnight

 

 

7/5/2004          Drained glycerine – approx 10 gal with some soapy material

                        Started spray wash

                        Noticed soapy layer forming in sight tube (off white colored)

                        Sprayed in 15 gal of water, then drained cloudy water and soapy material

                        Sprayed in another 15 gal of water, more soap formed, drained cloudy water and soapy material.  Let stand overnight.

 

                        At 0900 inspected both Mason jars and both had layers of soap nearly 1cm in height above glycerine layers.

 

                        Not sure why such prominent soap layers formed.  Maybe jars still had residual water in them from recent cleaning?  Maybe water present in feedstock oil, but settled to bottom, stirred up when mixed?  Will perform mini-batch after feedstock has settled for 1 hr using 6.3gr Lye.  In meantime, am preparing a mini-batch of mixed feedstock oil using 6.1gr lye as previously done 7/2

                        No visible soap layer formed in 6.1gm sample

 

 

7/6/2004          Inspected material in tubing – biodiesel becoming clear, soapy layer       present, water nearly clear.

                        Drained water

                        Sprayed in 15 gal of water

                        White haziness appeared in tubes showing water level and haziness        appeared in tubes showing biodiesel.  Soap layer remains present.

                        Drained water and soap layer

                        Took sample of cloudy biodiesel in Mason jar to inspect

                        Examined processor and discovered that the paint had come off of the   sides in sheets/strips/chips

                        With paint in the biodiesel, transferred this batch to a 55 gal drum to store

                        Sample in Mason jar showed settling of paint particles

                        Hopeful that given enough time, this biodiesel will be salvageable

                        Processor abandoned

 

                        Mini-batch at 6.3gm NaOH with no stirring of feedstock results in no soap layer – confirms suspicion that water settling in feedstock barrel and contaminating oil, creating soap when the NaOH /methoxide is introduced

 

                        Do not stir up oil prior to filtering and reacting with methoxide, let it settle before dumping it into the processor and don’t take oil from the bottom of the barrel

 

7/8/2004          Batch #2 – 2nd Generation Processor

                        Single stage method

                        40 gal oil, titration to 4.7gm NaOH (1.2mg from titration + 3.5mg)

                        Temp 120-125F

7/9/2004          Separation of biodiesel and glycerine – no soap seen

                        Spray wash with soap formation

                        Sprayed 10 gal of water, let stand overnight

 

7/10/2004        Drained water and soap, sprayed in 10 gal, let stand overnight

 

7/11/2004        Drained water and less soap, sprayed in 10 gal, let stand overnight

 

7/12/2004        Put in blue aeration stone and bubbled overnight

 

7/13/2004        Drained water, clear in color, small amount of soap, let stand overnight

 

7/14/2004        Transferred washed biodiesel to storage tank, pumped initial 1-2 gallons back into processor (to be sure to keep any impurities that had settled to bottom of biodiesel layer out of the storage tank)

 

7/14/2004        Batch #3 – 2nd Generation Processor

                        Titration result is 4.6mg NaOH (1.1mg from titration + 3.5mg)

                        Temp 120-130F

                        40 gallons used oil, 696.5mg NaOH from calculation (used 700mg) and 8 gallons of methanol combined (first made methoxide, and then mixed with oil)

                        Mixed oil with methoxide for 90 minutes, then settled.

 

7/15/2004        Drained glycerine (approx 6 gal)

                        No soap layers

                        Transferred to wash tank after purging line with new biodiesel (emptied to glycerine bucket)

 

                        Storage tank biodiesel appears clearer than earlier

                        Pumped some storage biodiesel into BIOBUG, probably too early as it had       not settled for several days, but Barb insistent.

                        Emptied all mini batch biodiesel into wash tank with Batch #3

                                    Noted glycerine ‘cake’ in jar of 5.6gm NaOH, not in 4.5 gm jar

                                    ?Will this be a characteristic of glycerine from jars with the higher                                   NaOH concentrations?

                                    Jar marked 6.6gm NaOH with well formed ‘cake’ of glycerine

                                    Conclude that the glycerine by-product becomes increasingly solid                                 with increasing amounts of NaOH used (avoid using too                               much NaOH in process – could clog processor)

 

                        Started spray wash – tiny soap layer up to 4 gal, then noticed thick                                soap layer at 10 gal of water.

                        Sprayed in 20 gal total – generous soap layer formed.

                        Drained water only, leaving 11 gal of soap layer

 

7/16/2004        Added 13 gal of new water

                                    Soap layer compressed to 10 gal

                        Drained 3 gal of water and 10 gal of soap

                        40 gal of biodiesel in tank

                        ?Does the sprayer I’m using agitate the biodiesel enough to cause soap formation or is something else causing soap formation?

                        Added another 15 gal of water via sprayers and thin layer of soap formed

                        Let stand overnight

 

7/17/2004        Drained water (pH 7), clear in color, then the thin soap layer and a bit of biodiesel

                        Transferred biodiesel to storage tank

 

7/27/2004        Batch #4

                        Changed wash – added vinegar to biodiesel, then the water, then started            the bubbler

                        Very little soap

 

8/9/2004          Batch #5

                        Titrated to 4.4gm NaOH

                        Good separation of biodiesel and glycerine, no soap

                        Started the bubble wash, forgot vinegar, then added 90ml 10 minutes after         starting bubbler – soap layer formed – not big, but bigger than           batch #4

 

Global problem with the PVC tubing weeping the biodiesel, delaminating from the nylon braids.  Have ordered polyurethane (ether) tubing

Global seepage of fluids from most threaded joints despite use of Teflon tape (disintegrated), and two different thread compounds

 

Gap in log entries

 

9/6/2004          Then added water for first wash using 10 gal.  No soap seen initially

 

9/7/2004          1003 – drained 9.5 gal wash water, milky white, pH 5

                        Added 8 gal fresh water, bubbler on

 

9/8/2004          1723 – drained 7.5 gal wash water, milky white (thicker than 9/7) with pH 10

                        1726 – added vinegar, 300ml, bubbler on

                        1812 – added fresh water, 6 gal, bubbler on

 

9/9/2004          0856 - 6.5 gal clear water drained, pH 4

                        6.5 gal fresh water added, bubbler on throughout

 

9/10/2004        1635 – drained wash water, no soap layer visible, pH 7

                        Biodiesel settling in wash tank

 

From here on, I got a bit lazy with the log entries.  To summarize, the polyurethane tubing arrived and was installed.  It seems to be holding up better with no leakage/weepage over the past several weeks.

 

                        I used different thread compounds and found one called Christy’s Superseal to be the best.

 

                        The first processor was resurrected and cleaned up.  It was prepped  according to recommendations from the POR 15 producers.  This involved a special cleaning solution, a special metal prep solution and finally, the paint – POR 15.  Everything looked great.  This refurbished processor (a 55 gallon drum with lid) was put back into the system.  The newly rejuvenated processor allowed for the use of pressure during the mixing and a band heater to keep the temperature up.

 

                        It all worked well the first batch, then the second batch ended with disaster.  The chemical resistant paint, POR 15, started peeling off and eventually plugged the pump with fragments of paint.  With help (my dad and sister who were visiting), one of the mixing tubes was disconnected and the contents were strained through a colander, then suctioned back into the system by the pump (all from a 5 gallon bucket!).  I’m still picking up fragments of black paint in my filters.

 

                        Disgusted with the whole thing, I considered abandoning the effort of home brewing in favor of just trying to buy biodiesel or waiting for it to be available locally.  Well, after pulling the 55 gallon tank out of the system, I put the plastic 55 gallon conical bottomed tank back into the system (no paint to peel).  Heating became problematic since I had decided to go to the two stage method of converting oil to biodiesel (used oil has a free fatty acid content higher than virgin oil).  Since the two stage method involves acidification of warm oil, a period of 8 hours, then alkalinization (base part) of warm oil, I needed a way to heat the oil without melting the plastic tank.

 

                        I had a spare spa heater sitting around (240V 6000watt variety), so I hooked it up to a water heater thermostat (my dad’s idea) glued to the side of the tank, wired it for 120V operation and plumbed it into the system after the pump.  It worked very nicely without leaking (so far) and keeps the circulating fluids at 130 F.

 

                        The next batch of biodiesel went well.  The two stage process produced a nice ‘crack’ of biodiesel and glycerine (no soap layer).  The water washing stage needed some acetic acid (white vinegar) to keep the foam down to a minimum.  The wash water removed the visible soap.  Upon transferring the finished product to the settling/holding tank, a fair amount of soap precipitated to the bottom of the settling tank.  This had not happened in prior experiences.

 

                        The most current batch is resting in the wash tank after several days of washing.  The bubbler bubbled for 3-4 days while I’ve been busy (installing a 240V 3000 watt garage heater to keep the biodiesel from turning to jell-o) doing other things.  We’ll see what happens!

 

Cold temperature experiments:

                        Using the refrigerator/freezer, I put a sample of biodiesel in a mason jar and shoved a thermometer through the lid to keep track of the temperature.

                       

 

Sample 1:         Temperature                             Description

30 F                                         Gelled/Pudding – stirring liquefies to very thick (barbecue sauce)

40 F                                         Opaque, thick fluid (tomato soup)

56 F                                         Cloudy thin fluid (hot olive oil consistency)

70 F                                         Clear, thin fluid (watery)

 

Sample 2:         2 F                                           Solid – ice cream

32 F                                         Gelled, jell-o, opaque thick fluid after stirring

52 F                                         Cloudy with particulates visible floating about.  Fluid thin (like hot oil)

70 F                                         Clear, less particulates

80 F                                         Clear, less particulates

 

Sample 3: 0.25 ounce of PowerSource (diesel antigel compound) added to Sample 2.

                                                           

                        80 F                                         Visible particulates, clear, thin

                        50 F                                         No particulates, slightly cloudy

                        30 F                                         Opaque, thick fluid

                        10 F                                         Gelled, nearly solid