Rigorous Process Simulation Services for the Vegetable

oils & Fats refining industry (Degumming - Neutralising

– Bleaching – Deodorising/Physical Refining)

PROCESS SIMULATION TECHNICS

ProSimTechs MODELLING & SIMULATION

The Acid Degumming/Neutralising process

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Acid Degumming and Neutralising are the

first steps in the entire refining process, and a

very important stage in terms of the

appropriate quality of the degummed/refined

vegetable oil, in terms of fatty acids and

phospholipids removal

Along the overall refining process, the Acid

Degumming/Neutralising process is by far,

the process stage where the higher NOL

(Neutral Oil Loss) takes place.

What we want to remove at this process stage?

Quality

To remove phospholipids, FFAs, solid

impurities ?

Do we need to know at first the type of

phospholipids the inlet vegetable oil contain?

Do we have a given target of residual

moisture in outlet refined oil ?

Process conditions

Besides the quality, we need to define most

efficient process for obtaining the required quality

of refined oil, considering the following aspects:

- Yield /losses

- Consumption of auxiliaries as chemicals

- Effluents generated

- Energy recovery

- Type of by-products (soapstock/gums) generated

Process

Type of Process

Flow diagram

Equipment

Process condition

s

Lab results

Neutralising

Bleaching

Deodorising

Acid Degummin

g

Acid Degumming/Neutralising Process

Ca or Mg O P

H

ProSimTechs MODELLING & SIMULATION

The performance in terms of refined oil quality and NOL

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The Acid Degumming/Neutralising Process Unit is one the

economic heart of today’s refinery. Small reductions in NOL

(Neutral Oil Loss) can bring significant gains in productivity and

revenues.

Rigorous process simulation studies have diagnosed operating

problems and helped improve the performance of all major

components of this process stage .

Each project is customized to provide the information needed

to optimize or troubleshoot your specific process.

Data collected can be used to identify operating parameter

changes to improve unit productivity, or gauge the accuracy of

process modeling and simulation.

A typical study employs a rigorous, accurate

and customized model of the process taking

into account the characteristics of the oil, the

flowsheet and the equipment.

The starting information for the complete

study is the actual information managed by

the plant, for example:

Capacity of processing

Vegetable oil inlet-outlet composition –

Distillate composition

Flowsheet (P&IDs or PFDs) and

equipment characteristics.

Current process conditions

DRAWING SOURCE: WESTFALIA

ProSimTechs MODELLING & SIMULATION

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Modelling and Process Simulation

Process modelling is the activity of building a

mathematical model of the process by describing its

fundamental physical and chemical relationships, by

means of equations.

Process modeling and simulation are used to describe a physico-chemical process as a set of

physic-chemical equations in order to perform all the calculations involved in it, in a powerful,

accurate, reliable, quick way.

A point during the process of building the model of the vegetable refining process, is to

select the appropriate models for each main parts of simulation model:

Thermodynamic models: the fatty compounds requires a very specific

thermodynamic model, more over considering Unit Operations with liquid-vapor

equilibrium (LVE) processes.

Unit operations models rigorous: most of the key process equipments are quite

particular and non std designs (deodorising trays, packed columns, scrubbers).

Compounds (basic data and temperature dependent properties): quite complex

molecules, a few info available, predictive approach is required.

cambiar

SCREEN SHOT OF A ACID DEGUMMING AND NEUTRALISING PROCESS SIMULATION

ProSimTechs MODELLING & SIMULATION

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Study case: Soybean oil refining in Acid Degumming/Neutralising

Relevant information for the Modelling

Process conditions

Oil inlet temperature (ºC)

Final heating temperature (ºC)

Temperatures in heat recovery stages

Oil outlet temperature (design)

Vacuum at Drying stage (mbar)

Temperature at Drying stage (ºC)

Oil outlet temperature (ºC)

Equipment

Type and general dimensions of

the main equipments

Heat exchange areas

Soapstock/Gums composition

FFA (%)

Phospholipids

Moisture

Fatty matter

Vegetable oil inlet composition

FFA (%)

Moisture (ppm)

Impurities (ppm)

Phospholipids (%)

Soaps (sodium oleate) (ppm)

Vegetable oil outlet composition

FFA (%)

Moisture (ppm)

Impurities (ppm)

Phospholipids (%)

Soaps (sodium oleate) (ppm)

Relevant information for validation of first simulation run

ACIDO FOSFATIDICO

FOSFATIDIL COLINA (PC)

FOSFATIDIL INOSITOL

FOSFATIDIL ETANOLAMINA (PE)

ProSimTechs MODELLING & SIMULATION

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Objectives

Modelling of the process

Simulation of a given scenario in terms of process conditions and oil inlet quality

Validation of the modelling against plant

Sensitivity studies

To compare different NOL scenarios in terms of OPEX

Piping and instrumentation diagram (P&ID)

Study case: Soybean oil refining in Acid Degumming/Neutralising

From the real P&Id of the plant,

we select the main streams of

each type of fluid, and the main

equipment.

A flowsheet of the process with

the main streams is then built,

in order to be considered during

the construction of the

simulation model of the process Low

pressure steam

Dynamic

mixer

Washing

centrifugal

separator

Heater 1

Dynamic

mixer

Acid

reactors

Centrifugal

Separator

Oil/oil

economiser 1

Citric acid

solution

(30%)

Caustic soda

solution (50%)

Process

water

Soapstock

Oil/oil

economiser

2

Heater 2

Citric acid

solution (30%)

Effluent

Fat trap

Neutralising/

Hydratation

reactor

To soapstock

Dynamic

mixer

Process Simulation Technics

Process Flow Diagram (PFD)

Acid Degumming / Neutralising

1.0

DESCRIPTION

PROJECT

RevPROCESS UNIT Date 01-02-2011

Low pressure

condensate

Low pressure

steamLow

pressure condensate

Water

degummed

oil

Heater

3

Low pressure

steamLow

pressure condensate

Oil/oil

economiser

3

Cooler

Cooling water inlet

Cooling water return

Refined

oil

Vacuum

system

Motive steam

Motive steam

Drier

Effluent

Cooling water inlet

Cooling water return

ProSimTechs MODELLING & SIMULATION

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Simplified Process Diagram + Relevant process information

Objective

- We want to determine the impact in OPEX, in function of an

increase of 0.1 % NOL, that ends up in the soapstock.

- To compare the soapstock compositon vs STD NOL soapstock

composition

- To prepare a complete OPEX comparative analysis in between both

simulation scenarios

ProSimTechs MODELLING & SIMULATION

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OPEX analysis on Chemical refining extra NOL 0.1 %

An extra NOL of 0.1 %,

which is feasible to detect

by process simulation and

soapstock comparative

between plant lab analysis

and simulation values, is

analysed by OPEX

calculations in both cases.

As it is shown from the

detailed OPEX table, the

OPEX by neutral oil losses,

that end up in the

soapstock, has a cost

weight in total gross OPEX,

in this neutralising process

case of around 83 %.

That is why, the total OPEX

is very sensitive to small

NOL values.

Finally, making a annual OPEX

calculation, considering the net OPEX

departure from STD, capacity plant and

330 working days/year, we have:

1- Quality specification of vegetable oil

Type of vegetable oil

water degummed

soybean oil

FFA (as oleic acid by titration) 0,10 %

Phospholipid (as P) 200 ppm

Volatiles 0,10 %

Impurities 0,10 %

Plant Capacity 600 TPD

2- Price of vegetable oil and by-products

Water degummed oil 1000 U$S/Ton

Soapstock 90,00 U$S/Ton

3- Operative cost of the different processes

RBD

(Chem)

RBD

(Chem)

Extra NOL Difference

U$S/Tn U$S/Tn U$S/Tn

OPEX per Tn water degummed oil 4,22 4,52

OPEX per Tn refined oil 3,05 3,06 0,00

OPEX x losses 14,79 15,79 1,00

OPEX total per Tn refinado 17,84 18,84

RBD OPEX 1017,84 1018,84 1,00

Byproduct income per Tn RBD 4,59 4,69 0,10

Net OPEX 13,25 14,16 0,91

RBD (Chem) RBD (Chem)

Extra NOL

Section Loss

%

NEUTRALISING 1,38 1,48

WASHING + DRYING 0,10 0,10

1,48 1,58

NOL excess 0,10

Annual OPEX departure USD 179.563

ProSimTechs MODELLING & SIMULATION

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Concluding remarks

Acid Degumming/Neutralising is a key process in terms of overall neutral oil

losses.

Vegetable oil is a multicompound mixture that directly impacts on

soapstock/gums composition.

Also configuration and type of the equipment plays a role towards a given product

quality.

Modelling and Simulation is an optimum and very valuable tool to predict and

analyse different scenarios and see “what if”.

The information from a simulation run, sensitivity analysis and global optimisation

allows to have an in-depth knowledge on our process, then to make the appropriate

decision-making.

There is a new point of view to analyze your processes. Let us exchange ideas.

info@prosimtechs.com www.prosimtechs.com

(C) 2013 ProSimTechs

ProSimTechs MODELLING & SIMULATION