Hi

I currently have a small plant (15,000 l/yr) running in rural India producing biodiesel from Jatropha oil, methanol and sodium hydroxide catalyst.

We have found a far cheaper feedstock in fish oil and I was wondering if and how the acid esterification process differs from the alkaline-based one we're currently using.

Sulphuric acid is available but comes with significant costs and we can only receive it in bulk so I want to gain some better knowledge in this area before I buy in volumes of it at the community's expense. Ditto with importing the fish oil. We're trying to work out if the fish oil is worth the investment.

Any information on the above would be greatly appreciated.

Thanks.

H Weston

Before you get involved with it, you should get a typical sample and test for FFA level (titration value, acid number, or percentage), or perhaps you know already. Let us know that value, and we can offer more helpful advice.

The acid process takes at least twice as long, 4 times would be a better number. You would need at least one settling tank between the acid and base stage. Since a large excess quanity of Methanol is used, a recovery system for the methanol is needed. The sulfuric acid is technically recoverable but requires some expensive equipment do to the high acid level. Depending on the water level in the raw oil you may need to heat it to over 110 C also.
Just a few issues that need to be addressed.