Olive processing wastewater composition? 1

[dalcazar]

Does anyone have experience in treating the wastewater generated by a 2-phase olive oil extraction process? I haven't been able to find reliable data on the net regarding the strength of the wastewater or the complexity of the molecules in it. (including the COD and BOD values contained therein). If anyone has had any direct experience with it, it would be extremely helpful.

I need to design the wastewater treatment facility and was wondering what would be the best way to go about it, I want to avoid anearobic processes if at all possible to keep the price down.

Also, a mass balance of the process would be helpful if you know of one.

 

[bimr]

I have not done olive oil, but imagine that it would be similiar to cottonseed oil processing.

A typical process will involve crushing the raw materials to remove free oil. Then a solvent extraction is used to remove the rest of the oil from the crushed mash. The solvent extraction process then utilizes distillation to separate the oil and solvent. The solvent is then recycled back.

There is minimal wastewater and the wastewater is mainly generated in the cleanup of equipment.

 

[dalcazar]

Unfortunately no, olive oil is the only oil that can be consumed without any form of processing, there is no chemical extraction involved in making extra virgin oil, which is what we're talking about here.

 

[bimr]

It seems that solvent extraction is used in the olive processing industry to reduce the waste volume. The point that I was making was that the industry has generally reduced the wastewater though the application of different processes.

You may want to get the book "An Introduction to Olive Oil Processing".

THe website:

http://www.oliveoilsource.com/olive_waste.htm

Has this quote:

"2 phase olive decanters require little added water and produce oil and a watery husk. In 2004 roughly 90% of Spain's 1,753 olive oil mills operate in a two-phase system. The watery husk is considered less of a disposal problem than the olive water produced in a 3 phase decanter. It can be spread back on the field, trucked to landfill or is occasionally dried onsite in commercially available dryers. The dryer may cost more than the decanter and consume high quantities of energy in the form of electricity, fossil fuels or by burning the subsequently dried husk. In all cases, greenhouse gasses and fumes are produced."

 

[bimr]

It appears there that there is a lot of information available to you. Here is a paper that shows the waste material can be composted:

http://www.actahort.org/books/549/549_7.htm

http://www.staffs.ac.uk/schools/sciences/consultancy/cet/pubs/olive.pdf

The 2-Phase Centrifugal Extraction of Olive Oil ..."produces no wastewater (margine) as such, it combines that wastewater that isgenerated with the solid waste (grignon) to produce a single effluent stream of semi-solid (30% solidby mass)"

 

[dalcazar]

Good research bimr, but if possible we want to work with a 5-phase system where the solids come out much much drier and there is a wastewater flow because we don't have the space to compost on site so we have to pay to have the solids removed.

unfortunately there is no real detailed information that I've been able to find, only general descriptions.

 

[bimr]

Since this is a food waste, have you investigated outsourcing this to farms? Would think that this material would have added value for mixing into livestock feed.

 

[dalcazar]

that is one of the uses of it, and there is a very large cattle farm on highway 5 here in california, but I don't know how much they would charge to take it away, it's easily 60 miles, there is no significant animal farming in our area. I wonder what they would put it with though because no animal will touch olive paste that I know of.

We're getting a pretty good rate for composting the solidsn at a somewhat local farm, but again we want to reduce that cost by as much as possible. if we can recycle the water and use it for irrigation we'd be saving that much more, it's the composition of this water I can't find.

correction for before, we want to work with 3-phase and not 2-phase.

 

[dicksewerrat]

You may have to have it tested to get all the strange compounds before you can process it the right way. I can't believe this hasn't been done. Look for an aminal food manufacturer for the solids. they may take it for the trucking costs.

Richard A. Cornelius, P.E.

http://WWW.amlinereast.com

 

[bimr]

On page 5 of the Staffordshire paper, a wastewater analysis is presented. If it is not for the same application, why not send them an email to Staffordshire and ask them for a typical wastewater analysis.

It is doubtful that it is going to be economical to treat such a high strength waste, especially if the crops are seasonal.

 

[dalcazar]

any idea where I can get in touch with them?

 

[bimr]

http://www.staffs.ac.uk/schools/sciences/geography/links/IESR/Skerratt.htm