Fish oil

Fish Oil Processing Centrifuge | Fish Meal Production

Fish Oil Processing Centrifuge

A fish oil processing centrifuge is an industrial centrifuge that separates fish oil and fish meal from the process water, also known as stick water. Industrial fish processing involves cooking and grinding leftover fish parts that are separated into fish oil, stick water, and protein or fish meal.

Operation

Fish oil centrifuges operate by using a high centrifugal force to affect the separation of the three phases of processed fish residue. These centrifuges separate Fish Oil, Fish Meal, and stick water from inedible fish processing residue. The fish residue consists of non-saleable fish parts such as skin, guts, heads, bones, offal, and fins.

Methods of Centrifuging in Fish Processing

Pre-centrifuge Fish Processing Steps

The incoming fish leftovers and water are heated in a cooker. This process sometimes uses steam to break down the raw fish and release the oil.

The cooked fish biomass passes through a screening process to separate the bulk of solids from liquids. The solids separated at this phase are proteins. This solid phase is dried and is known as a fish meal. Fish meal is a valuable product for many commercial uses in aquaculture and agriculture.

The liquid phase from the abovementioned process consists of oil, water, and fine solids. There are two ways to separate this fluid's three phases (oil, water, and solids).

Using a Tricanter for Fish Oil Production

The first method uses a tricanter or a three-phase decanter centrifuge to separate the oil, water, and solids simultaneously. A tricanter is a three-phase horizontal centrifuge that separates bulk solids from water and oil. So, a tricanter processing this strained fluid separates the remaining fish meal from the stick water and fish oil.

However, there is an inherent limitation with using a tricanter due to the lower centrifugal force generated. A lower g-force may not be sufficient to efficiently separate the oil and water phases in the feed.

Using a Decanter and Disc-Stack Centrifuge for Fish Meal

The other method is a two-step process using a 2-phase decanter centrifuge as the first step to de-sludge the process fluid. The decanter separates the fish meal solids from the oil and water. The oil and water fluid passes through a three-phase disc-stack centrifuge in the following step.

The following diagram shows a fish oil and fish meal processing plant designed by KOEN The disc-stack separator exerts a higher centrifugal force than the decanter, separating the fine solids and the oil from the stick water continuously. The separator discharges the fish oil and stick water through independent outlets while intermittently ejecting the fine fish meal solids.