Material flow analysis. Making material flows visible

Transcription

1 Material flow analysis Making material flows visible 1

2 How does a balance work? A balance traces flows within a defined time frame input mass = output mass + storage it is assumed that there is no chemical reaction present 2

3 Goals of a material flow analysis: to observe raw materials through the company to identify and demonstrate linkages in the process to trace waste and emissions back to the place where they were produced to identify and demonstrate weak points (inefficiencies) to elaborate the material flow basis for evaluation and optimization to present data in view of decision making to give priority to sensible measures for waste and emission minimization 3

4 What are materials? Purchased 10 kg Einkaufsmenge 10.0kg goods/material e.g. Wood Water Gravel PVC Varnish 8 kg, thinner 2 kg Prepared varnish 8,5 kg Applied varnish 7,5 kg Residual varnish 1 kg Thinner 1,5 kg Chemical compounds e.g. Benzene Methane Solvent in exhaust air 1,5 kg 2.5kg Overspray 5.0kg Solvent in exhaust air 3,5 kg Solids in exhaust air 0,1 kg elements e.g. Carbon Cadmium Oxygen Dry varnish film on workpiece 1 kg Dust 0,1 kg Sludge 1,3 kg 4

5 Selection Criteria Purchased 10 kg Einkaufsmenge 10.0kg Quantity: Mass Varnish 8 kg, thinner 2 kg Prepared varnish 8,5 kg Residual varnish 1 kg Cost Applied varnish 7,5 kg Thinner 1,5 kg 2.5kg Overspray 5.0kg Quality: Solvent in exhaust air 3,5 kg Toxic properties Solvent in exhaust air 1,5 kg Solids in exhaust air 0,1 kg Legal requirement Dust 0,1 kg Storage restrictions, etc. Sludge 1,3 kg Dry varnish film on workpiece 1 kg 5

6 How do we conduct a material flow analysis? 1. Definition of goals 2. Identification of considered parameters 3. Consideration of limitations of the balance-frame 4. Consideration of limitations of the balance-period 5. Identification of metering system 6. Recording and defining the production steps 7. Drafting the flow sheet: material flows - in quality 8. Balancing: material flows - in quantity 9. Interpretation and conclusions 6

7 Material flows in a car repair paint shop: before and after optimization Purchased 10 kg Einkaufsmenge 10.0kg Purchased -7,84 kg Varnish 8 kg, thinner 2 kg Varnish -6 kg Thinner 1,8 kg Prepared varnish 8,5 kg Residual varnish 1 kg Prepared varnish - 6,6 kg Thinner 1,3 kg Applied varnish 7,5 kg Thinner 1,5 kg Applied varnish - 5,7 kg Residual varnish 0,9 kg 2.5kg Overspray 5.0kg - 1,25 kg Overspray - 4,4 kg Solvent in exhaust air 3,5 kg Solvent in exhaust air 3,4 kg Solvent in exhaust air 1,5 kg Solids in exhaust air 0,1 kg Solvent in exhaust air 1,3 kg Solids in exhaust air 0,1 kg Dust 0,1 kg Dust 0,1 kg Sludge 1,3 kg Sludge 0,9 kg Dry varnish film on workpiece 1 kg Dry varnish film on workpiece 1 kg 7

8 Material flow analysis of machine painting 8

9 Structure 1 Step 1: considered parameters Paints Solvents all process materials Step 2: definition of the balance frame painting chamber and drying Step 3: definition of the time frame 1 hour 1 week 1 month 1 year What else might be reasonable? 9

10 Structure 2 Step 4: definition of operating steps pre-treatment priming / painting Drying Step 5: identification of additional processes steam generator exhaust air filter Spray gun- and container cleaning Step 6: drawing of a flow sheet Representing process steps with rectangles Representing process flows with arrows 10

11 Flow Chart - Prozesses air filter pre-treatment priming/ painting drying steam generator cleaning Balance Frame 11

12 Flow Chart filled filter Paint, thinner, container Filter, paint air filter Air, thinner Air and thinner Air, paint, thinner Parts with oil pre-treatment Cleaned parts priming/ painting tools Wet parts drying Painted parts steam generator cleaning water thinner Waste thinner Dust containers Balance Frame 12

13 Quantitative material flow balance 13

14 Quantitative material flow balance - Detail 14

15 Step 7: Interpretation by indicators and conclusions e.g. through parameter identification Calculation of the so called Application efficiency": dry surface film mass efficiency = solid state mass in the concrete case for small pieces < 10% in the concrete case on average < 20% State of the art? 15

16 Benchmarking: Typical efficiencies (application efficiency, expressed as % solids): 16

17 Evaluation of material flow analysis Flowsheets to illustrate material flows and processes, Pie charts and histograms to illustrate distributions and compositions, X-Y-graphics for chronological illustrations Sankeydiagramms to visualize material flows true to scale 17

18 Evaluation of material flow analysis 2 Indicators e.g: Data sources: Efficiency factors Book-keeping ratio between use and expenditure Quality factors ratio between real efficiency factor and the theoretically possible one Storage keeping Collection of process data Operational accounting personal information (e.g. methods engineer) Estimation Measurements Original documents own measurements Consider and evaluate data quality! 18

19 Data collection: the waste box 19

20 Evaluation of the waste box 20

21 Step by step optimization Purchased 10 kg Einkaufsmenge 10.0kg Purchased -7,84 kg Varnish 8 kg, thinner 2 kg Varnish -6 kg Thinner 1,8 kg Prepared varnish 8,5 kg Residual varnish 1 kg Prepared varnish - 6,6 kg Thinner 1,3 kg Applied varnish 7,5 kg Thinner 1,5 kg Applied varnish - 5,7 kg Residual varnish 0,9 kg 2.5kg Overspray 5.0kg - 1,25 kg Overspray - 4,4 kg Solvent in exhaust air 3,5 kg Solvent in exhaust air 3,4 kg Solvent in exhaust air 1,5 kg Solids in exhaust air 0,1 kg Solvent in exhaust air 1,3 kg Solids in exhaust air 0,1 kg Dust 0,1 kg Dust 0,1 kg Sludge 1,3 kg Sludge 0,9 kg Dry varnish film on workpiece 1 kg Dry varnish film on workpiece 1 kg 21