Dear Mr Myin, I have already answered the main points of this question in your previous one which was very similar. I think if you want such extreme and unjustified accuracy in your calculations you will have to analyse a few batches of your spent bleaching earth and take the average, because other people's figures will be different from yours. Different batch of crude oil, different bleaching earth, different plant and conditions. Regards, FP (03.03.2011)

Dear Mr Myin, You should take what is in the spent earth as oil. Strictly speaking it will have a higher concentration of colour compounds viz.carotenoids which you can only determine by analysis. But such extreme precision is is unnecessary and in any case you already paid for it as oil when you bought it. Regards, FP (03.03.2011)

Dear Mr Thesz, The statistics available are on the volume of biodiesel production in different countries, not on the composition of their feed stocks. Indeed I expect many biodiesel `producers would consider this as a trade secret. Also much vegetable oil is used directly as fuel without prior conversion into biodiesel and these amounts are not recoded any where. Of course writers in trade publications and speakers at conferences often mention figures, but usually the source of the data is a trade lobby with vested interests and one must take their figures with great caution. Regards, FP (03.03.2011)

Dear Mr Novalita, I regret I have not seen these engineering data published any where. But they can be calculated with reasonable accuracy. Regards, FP (25.02.2011)

Dear Mr Chee, Malaysia keeps excellent records for the commodities it produces and exports, but attempting to collect the kind of data you want would be ridiculously expensive and useless. However I expect practically all the olein produced will be used for edible purposes as the only other use I can think of is biodiesel. Regards, FP (25.02.2011)

Dear Mr Dizon, There are no hard data for the use PO in different products. Different people have made various estimates but they are old and without any explanations which undermines confidence in them. But PO is the biggest oil in world production and the biggest use of oils is in foods, especially frying and baking. Vegetable ghee is a very big use in India, Pakistan, Middle East etc. Margarine and shortenings in Europe and USA.. Cosmetics, soap, detergents, biodiesel, are also big uses. I think eventually PO will have huge use in biodiesel in Asia. Most countries there are short of petroleum and are warm enough to tolerate the high cloud point of PO biodiesel. Regads, FP (24.02.2011)

Dear Mr Patel, Assuming the M&I is 0.5%, caustic refining (which you have not told me) and average deodorisation losses, your total loss might be about 14%. If you get emulsions your loss will be much bigger. However most of the oil loss you will recover as acid oil. Regards, FP (22.02.2011)

Dear Mr Patel, The SFC of these oils has a wide range, especially that of palm stearin, and in best practice it should be checked for every batch. But at the standard room temperature of 20C, average values would be: PS 60%, PO 25%, PL 5%. Regards, FP (22.02.2011)

Dear Mr LMY, Citric acid is sometimes used instead of phosphoric but I think it woks out more expensive. There are not many other acids that can be used. The others are too corrosive or not permitted in foods or in effluents. Regards, FP (22.02.2011)

Dear Mr Henry, Your question is outside the rules for this page. So far the events in the Middle East have had little effect on veg.oil prices. But these have a strong correlation with petroleum and if any thread to the latter is perceived, PO prices will most probably follow. But you never know if another even will not upset expectations. Regards, FP (22.02.2011)

Dear Mr LMY, The oil loss in bleaching is not affected significantly by any of the parameters.you mentioned, when they are within the usual limits. In physical refining, which I assume you use, it is primarily affected by the amount of gums present.in the oil.These block the fine passages between the bleaching earth particles and those of the filter cloth and prevent the oil from draining properly.There could possibly be some correlation between the amount of gums and the FFA, but as far as I know, no one has yet tested it. I find it incredible that with so many big wealthy refineries in S.E.Asia, none of them is publishing any research, and yet there is nothing that will enhance their standing as much, or as quickly. Short sighted technical directors who are only concerned with profits tomorrow. Regards, FP (21.02.2011)

Dear Mr Ng, Quality is reflected in many different properties and you have not said which one you have in mind. The only value that I know to affect the olein yield is the IV and this can easily be proved mathematically. Regards, FP (18.02.2011)

Dear Mr Ng, It is natural for oils to form some foam if they are made to splash down from a height and for that foam to subside gradually. But if that foaming is more than usual, it is a sign.of poor quality. Also it is bad practice to have the oil inlet pipe stop at the top of the tank and so cause maximum aeration. Unfortunately most engineers know nothing about oil quality and some of the bad designs I have seen beggar the imagination. Regards, FP (17.02.2011)

Dear Mr Ng, You are quite correct, I too have noticed it when I was working with PFAD. At first I thought it was experimental error in the test, but it happened too many times and I had to believe it. The FFA drop goes on and can get much bigger over time. The only explanation I can offer is polymerisation in the linoleic acid content. but I admit the matter needs experimental investigation. Regards, FP (17.02.2011)

Dear Mr Herdiansyah, There is nothing wrong with your antioxidant and assuming you do not grossly overuse it, the amount of acid in it cannot account for any significant effect on the FFA analysis. So I have no explanation for your FFA rise. But if it is made by one of the big Western companies it is worth you asking them to comment. But to prove that it is happening beyond reasonable doubt, you must test the same batch of oil on the same product in the same fryer, alternating with and without antioxidant each day and get a positive result 5 days in a row. Regards, FP (17.02.2011)

Dear Mr Herdiansyah, Antioxidants are meant to suppress PV increase, not FFA. Even for that the results depend on the circumstances. So, unless you want to extend the shelf life of your products, you are wasting your money. I cannot tell you why your FFA is increasing because you have not told me the composition, or even the brand name, of your antioxidants and there are dozens of them on the market. Regards, FP (16.02.2011)

Dear Mr Patel, The relationship between RI and IV depends on the type of oil and the temperature That is why refractometers have thermostatically controlled water circulation. As tempeature changes the RI changes but the IV does not. For PO IV 52.5, the RI is 1.455 at 50C. Regads, FP (14.02.2011)

Dear Mr Patel, Refining losses depend on the type of oil involved, its age, actual analytical values including gum levels, not simply its specification, bleaching dose, etc. Also just the name of the plant is not enough as plant constructors have different versions and introduce modifications all the time. Consultants have to visit clients and preferably also talk to the constructors, before offering advice on plants. It cannot be done from thousands of miles away and a few lines on the internet. Regards, FP (14.02.2011)

Dear Mr Adnan, To give you full instructions on two methods of soap making would need many pages and this column is for simple, short, explanations. The only difference between the hot and the cold process is that the hot one is quicker. You have not told me what is wrong with your soap, "does not come out good" means nothing. As regards your formula, the mount of water is far too much and you should reduce it to 25kg. Dissolve the caustic in it fully and start adding it to the mixer slowly and steadily when about half the oil charge is in. Regards, FP (14.02.2011)

Dear Mr Mohamed, Please read my answer to Q1062. You have told me your batch size, from which I can guess you will have a batch process, but before I can give you any estimate of yield, you must at the very least also tell me the FFA of your CPO, its moisture and impurities, and the amount of bleaching earth you expect to use, which will depend on the colour standard you want in the RBD oil. As you see, when it comes to processing a lot of information is needed before any meaningful calculations can be made. Any fool can give you a figure out of a hat and leave you to take the consequences. Regards, FP (11.02.2011)