Ecoefficiency Study in a Sunflower Oil Mill

1
Eco-efficiency Study in a Sunflower Oil Mill

• Sibel Uludag-Demirer (Dpt. of Industrial Eng.,
  Çankaya University, Ankara)

2
The share of SMEs in

• total economic growth
• industrial pollution

90 in Europe (Hillary, 2000) 74 in Turkey
(DIE, 1996)
70 (note that the environmental data is very
limited for SMEs) (Hillary, 2000)
3
The major drivers for taking environmental
actions for SMEs

• Social Responsibility
• Legislation
• Public Awareness
• Financial Benefits
• Internal/External Benefits
• Improved Image

4
Eco-efficiency is a management tool encouraging
industries to create more value with less impact.

• Eco-efficiency
• allows industries to be more profitable,
• makes industries to be environmentally
  responsible,
• improves the performance of industries,
• minimizes waste production,
• avoids end-of-pipe solution or lowers its share
  in waste management.

5
Eco-efficiency focuses on practices throughout
the industry, such as,

• lowering the chemical usage,
• preventing material loss during storage,
  handling, transportation,
• operating the units at optimum conditions (amount
  of additives, optimum T and P, etc.) to achieve
  higher performance,
• searching for water and energy saving
  opportunities,
• environmentally and economically sound residual
  management opportunities.

6
Eco-efficiency focuses on the economical
efficiency that will result in environmental
benefits while cleaner production targeting
environmental benefits, which brings in
economical benefits in most of the applications.
Eco-efficiency applications precondition the
industry for cleaner production studies, while
implementing cleaner production strategies
improves the eco-efficiency of the industry.
7

• Eco-efficiency applications are very
• suitable for SMEs due to
• their low or no investment requirements
• short pay-back periods
• easy and fast applications
• direct effect on reducing the environmental
  impacts

8
Methodology for eco-efficiency

• A- Analysis of the production by auditing the
  entire system
• collect data about the production, such as, raw
  materials used, material
• handling techniques, processes and their
  operational conditions, generation
• of product and waste, waste management practices,
  etc.
• develop process flow diagrams for each department
  and construct
• mass/energy balance.
• define and predict immediate environmental
  benefits as outcomes of a better
• operational and waste management using typical
  indicators, such as, use of
• hazardous compound, use of obscelete
  technologies, production of waste in
• large quantities, lack of waste management.
• recognize the existing eco-efficiency
  applications in the system and analyze
• their benefits.

9
Methodology for eco-efficiency-cont.

• B) Identification of eco-efficient opportunities
  for the activity
• analyze the problems related with material
  selection, handling and facility layout
• analyze the mass/energy balance to define
  material loss and wasted energy for each unit
  process
• compare the operational conditions with the
  conditions reported in relevant literature and
  sectoral guidelines or fact notebooks.
• investigate a better waste management focusing on
  minimization.

10
Methodology for eco-efficiency-cont.

• C) Evaluation of Opportunities
• Technical feasibility
• Economical feasibility
• D) Implementation

11
Objectives of the case study

• Company Name Eskisehir Oil Industry
• carrying out an industrial audit to collect the
  data required for developing process flow diagram
  and material balance
• determining the points of eco-efficiency
  applications
• reporting and testing the required changes and
  modifications proposed
• estimating the benefits
• calculating the pay-back period when initial
  investment is necessary

12
Facts of Eskisehir Oil Industry

• Product vegetable oil from sunflower seeds
  (RavinTM)
• Annual turnover 3.5 million USD
• Number of employees 23
• Capacity 12 000 tons from 30 000 tons of seed
• Seed composition 40-48 oil and 8 moisture
• Other activities refining crude oil (corn,
  cotton) in the periods of seed shortage
• Wastewater treatment plant simple physical and
  chemical treatment units (neutralization and
  sedimentation)

13
Methodology of the case study

• Entire production cycle was observed.
• Process flow diagram was developed.
• Existing eco-efficiency applications were
  determined.
• New eco-efficiency applications and their
  pay-back periods were determined.

14
An example for the checklist used in the study
based on hexane (solvent)
15
Calculation of pay-back period

• Pay-back period the length of time it takes for
  the revenues from
• a project to equal the initial investment costs.
• This approach was adopted in this study due to
• its simplicity
• existence of no alternative eco-efficiency
  applications for the same problem to compare in
  the study
• although there are some drawbacks in using the
  payback period,
• such as
• ignorance of the time value of money
• not showing the costs and savings beyond the
  point where the project pays for itself.

16
Process Flow Diagram and Material Balance based
on a Unit Production in Eskisehir Oil Industry,
Eskisehir, Turkey (annual capacity12,000 tons of
vegetable oil).
17
Current Eco-efficiency Applications

• Sieves used to remove the foreign materials from
  the sunflower seed have been installed
  individually resulting in savings in energy and
  increasing the life span of the sieves.
• The sludge produced in bleaching unit is burned
  in the incinerators for heat spacing, which is a
  solid waste minimization practice.
• The by-products, pulp, stearin and fatty acids
  are sold to the animal fodder and soap
  manufacturers respectively.
• They reuse the plastic containers of the
  phosphoric acid for storage in the plant.
• The packaging department is donated by automated
  pumps preventing any product loss.

18
Recommended Eco-efficiency Applications

• Applications with no pay-back period calculations
• The use of phosphoric acid in the degumming
  process can be replaced by citric acid, which is
  less expensive and easy to apply.
• The water used for cooling the steam (20 m3/hr)
  can be recycled and then reused in the process.
• The steam used in the physical processes,
  refining, and extraction can be used for space
  heating in filling station, which has no heaters.
• The temperature in the odor control unit is set
  to 220C, which is in the range of a typical
  temperature used in the odor control units
  (180-260C). They can save significant amount of
  energy by lowering the temperature in this unit
  by keeping the odor removal at the desired level.
  

19
Recommended Eco-efficiency Applications-cont.

• II. Applications with pay-back period
  calculations
• The Problem Sunflower seed loss (923 kg/year)
  during the sieving process
• The Solution Raise the height of the sieves at
  least by 3 mm using a steel sheet keeping the
  swinging rate the same.
• Economic Analysis

The purchase of a steel plate (6 USD/m2) with an
area of 2 m2
20
Recommended Eco-efficiency Applications-cont.

• II. Applications with pay-back period
  calculations (cont.)
• The problem Optimization of the amounts of
  bleaching additives (bleaching clay and TriSyl)
  to decrease the oil content of the bleaching
  sludge.
• The solution The amounts of additives were
  adjusted to the recommended amounts in the
  literature and oil content of the sludge produced
  before and after changing the amounts of
  additives was determined experimentally using
  hexane extraction method.

21
Recommended Eco-efficiency Applications-cont.
Experimental Work

• Purpose determine the oil content of the
  sludge produced in the bleaching unit.
• Method
• 1. Known weight of sludge was extracted
  using hexane for 6 hours in a 250 mL Soxhlet
  apparatus.
• 2. Solvent was then evaporated under
  reduced pressure at 40C.
• 3. Desolventized oil was filtered to
  remove the particulates and weighed.
• 4. The water content of the sludge was
  determined using xylene.

22
Recommended Eco-efficiency Applications-cont.
based on 50 kg sludge production. Altiokka
and Altay (1991).
23
Recommended Eco-efficiency Applications-cont.

• Experimental results showed that the oil content
  of the bleaching sludge decreased to 25 from 41
  (dry weight) after changing the amounts of
  additives.

Economic Analysis
Recovered oil is assumed to be processed with
100 efficiency to produce the vegetable oil.
24
Recommended Eco-efficiency Applications-cont.

• Other outcomes of the proposal
• Rate of filtration increases.
• Frequency of filter cleaning decreases.
• Amount of sludge produced decreases.
• Loss of natural antioxidants is prevented.

25
Recommended Eco-efficiency Applications-cont.

• II. Applications with payback period calculations
  (cont.)
• The Problem Significant amount of hexane loss
  during the production (atmospheric emissions,
  residual hexane in the pulp, leakage from the
  tank, volatilization,etc.)
• The solution Recovering the hexane vapor
  mixed with steam and pulp, reducing the hexane
  emissions by installing the proper equipments.
• Economic Analysis

excluding the operational and maintenance costs.
26
Recommended Eco-efficiency Applications-cont.

• Other Outcomes
• Protection of workers health and environment by
  preventing the hexane emissions,
• Increasing the quality of the oil and other
  by-products by reducing the residual hexane.

27
Conclusions

• Making the management and employee recognize the
  current eco-efficiency applications motivated
  them in involving proposed eco-efficiency
  applications.
• The benefits of some of the proposed
  eco-efficiency applications could not be
  determined due to the difficulties in valuation
  the impacts and in testing the proposed changes
  on the process.
• The proposed eco-efficiency applications to
  prevent the seed loss in sieving process, to
  reduce the amount and oil content of the
  bleaching sludge were implemented immediately by
  the industry.
• Although the hexane recovery project had a longer
  payback period, the management agreed on
  investing on this project in near future
  considering the monetary, health and
  environmental outcomes of the project.
• This study showed that the simple applications
  may result in significant benefits and reduce the
  environmental impacts in SMEs.