Some aspects on the sustainable process design in a timber mill using the design for manufacturability/sustainability

Figures & data

Figure 1. Research methodology.

Figure 2. CAD Model of the product and its specifications.

Figure 3. Timber manufacturing sequence.

Figure 4. Sawmill subsystem layout.

Table 1. Data input for sustainability analysis as per the current facility setup.

Material Class	Woods
Material Name	Pine
Part Weight	15793.52 gm
Built to Last	50 Year
Duration of Use	45 Year
Manufacturing Region	Australia
Manufacturing Process	Custom
Manufacturing Natural Gas	146 BTU/gm
Scrap Rate	40 %
Paint	No paint
Surface Area	2.45E+06 mm^2
Use Region	Australia
Truck Transportation	163 km
Percent Recycled	25 %
Percent Incinerated	65 %
Percent Landfill	10 %

Table 2. Fuel energy breakdown for manufacturing the timber.

Diesel	Operation Hours	Diesel (L)/Day	Diesel h	BTU
Generator	7.25	275	42.10345
truck	7	120	0.008286
Bulldozer	6	200	0.0008683
Loader in Forest	2	40	0.000666
Loader on site	7	150	0.002232
Company Transport (Navua to Sawmill)	1	17	8.5
Company Transport (Sawmill to Jungle)	2	22	11
Total consumption		824	61.6155	2268678.306
Petrol
Chainsaw	Operation Hours	Petrol(Litres)	Petrol h	BTU
	6	4	0.1667	22065.172
Oil
Chainsaw	Operation Hours	oil (Litres)	Oil h	BTU
	6	4	0.1667	24339.932

Table 3. Environmental Impact based on current facility setup.

EI Parameters	Carbon Footprint (kg CO2)	Energy Consumption (MJ)	Air Acidification (kg SO2)	Water Eutrophication (kg PO4)
Material	6.78273	36.40520	0.01402	0.00285
Manufacturing	15.24000	157.37800	0.06909	0.00378
Use	0.00000	0.00000	0.00000	0.00000
End of Life	10.17070	6.45821	0.00336	0.01272
Transportation	0.12354	1.75867	0.00055	0.00013
Total	32.317	202.000	0.087	0.019

Table 4. Technical specifications comparison for current and proposed setup.

Processor	Facility Specifications	Existing setup	Proposed setup
P2	Power consumption (KW)	100	21
	No. of blades	1	Maximum of 6, but 2 is enough for this case study
	Sawing wood width (mm)	Max. 400	Max. 600
	Sawing wood thickness (mm)	12-400	10-400
	Type of blade	Band saw
P3	Power consumption (KW)	75	9
	No. of blades	1
	Sawing wood width (mm)	100
	Sawing wood thickness (mm)	10-80	5-85
	Type of blade	Circular saw

Figure 5. Proposed facility layout.

Table 5. Environmental Impact for the revised facility setup.

	Carbon Footprint (kg CO2)	Energy Consumption (MJ)	Air Acidification (kg SO2)	Water Eutrophication (kg PO4)
Material	6.78273	36.4052	0.01401	0.002855
Manufacturing	13.0501	134.682	0.05923	0.003237
Use	0	0	0	0
End of Life	10.1707	6.4582	0.00336	0.01272
Transportation	0.1235	1.75867	0.00055	0.000128
Total	30.127	179.304	0.07715	0.01894

Table 6. Break-even point.

				Variable costs
Parts	Selling price	Production per day	Fixed cost	Material	Labor	Overhead	BEP in days
Construction timber (6x2 inch)	$1200 per m^3	30 m^3	$129,137.50	$400/m^3	$400/m^3	$300/m^3	44
Pallets	$25/piece	15 pieces/day	$21,934.90	$3/piece	$8/piece	$6/piece	183

Figure 6. Environmental impact comparison between existing and proposed setup.