Life cycle analysis  
  Life Cycle methodology was applied to evaluate the overall environmental impact due to production and disposal of Earthsoul® bags used by households to collect organic waste. Paper and polyethylene bags are the reference products. The evaluation includes raw material acquisition, production, processing and disposal of bags, as well as all transportation..

 
 

System Boundaries and Unit Processes

 
 

 
 

Selected Products

 
  The analysis is based on use and disposal of bags in the territory of Switzerland. The reference products have been taken from local distribution:

 
 
  Paper Bag Earthsoul Bag Polyethylene Bag
Material Kraft paper Mater-Biclass Z HDPE
Country of origin Paper: Sweden
Bag : Switz.
PCL: USA
Corn: France
Mater-Bi: Italy
PE: Malaysia
Bag: Malaysia
Disposal Composting Composting Incineration
Dimensions
(mm)
(240+105)
*510
(220+220)*440 (180+360)*600
Weight (gr) 59.6 9.15 7.04
 
 

Evaluation Model :

 
  The analysis is performed on the basis of the modified impact-oriented model (Heijungs, 1992; BUWAL 1996) and the impact categories of ECO-Indicator 95 (Goedkoop, 1995); the software of EMIS (Environmental Management and Information System, version 2.2) is used for all calculations. See bottom page for detailed description of impact categories. The study has been conducted by an independent Swiss organisation and certified with critical review according to EN ISO 14040.

 
 

 
  Paper bags definitely consume more energy than Earthsoul® and polyethylene bags, due to much higher weight.

 
 

 
  The Earthsoul® bag gives an important contribution to the reduction of green-house effect, thanks to the presence of its natural components.

 
  Mater-Bi Bag in comparison with:

 
 
Impact Category Paper Bag PE Bag PE Bag including residue organic combustion
Energy + + 0 +
Global warming + + + +
Acidification + 0 + +
Nutrification + + 0 +
Ozone creation + + + + +
Toxicity air + ++ + +
Toxicity water ++ 0 +
Salination _ _ _ + +
Deposited waste ++ _ _ _
 
 
  Deposited waste

 
  (++) = significantly better
(+ ) = better
(0 ) = comparable
(- ) = worse
(--) = significantly worse

  According to the LCA analysis, the Earthsoul® bag has significant lower environmental impact than paper bag, and similar impact to polyethylene bag incinerated alone after separation of the waste. Practical experience, however, shows that polyethylene bags sorted out at composting plants are polluted by organic waste stuck on the film. This organic fraction is incinerated together with the bags. When this effect is taken into consideration, the Earthsoul®® bag shows a much better environmental profile than the polyethylene bag. In any case, the Prithvi-Pran® bag is significantly better than reference products for the green house effect.

Detailed description of the impact categories considered in the analysis:

  Energy resources
 
  consumption of energetic resource (e.g. petroleum, natural gas), calculated from the energy contents of the required resources; (MJ).

 
  Global warming potential
 
  increase of average earth temperature because of gases; e.g. CO2, methane; (CO2-equivalent).

 
  Acidification potential
 
  acidification of soil and consequent damage of plants because of the release of substances like nitric oxides (NOx) and sulphur oxides (SOx); (SO2- equivalent).

 
  Nutrification potential
 
  disturbing of nutrient balance of water and soil on account of substances that have a fertilising effect, e.g. nitrate, ammonia; (PO4-equivalent).

 
  Ozone creation potential
 
  increased creation of ozone (summer smog) caused by release of substances like organic solvents and nitric oxides; (C2H4-equivalent).

 
  Toxicity to air
 
  pollution of air by harmful substances like organic compounds, nitric oxides (NOx). Weighting factors are calculated according to quality objectives (mg/m3), duration and/or degradation times.

 
  Toxicity to water
 
  pollution of water by toxic substances like organic pollutants, heavy metals, organic ions. Weighting factors are calculated according to quality objectives (mg/m3), duration and/or degradation times.

 
  Salination
 
  damage of flora and fauna in water caused by release of salts like chlorides. Weighting by number of ions (relative to acid as H+).

 
  Deposited waste
 
  amount of deposited waste: inert substances, reactive waste, hazardous waste, aggregated according to the procedure for the transport of harmful substance (BRAUNSCHWEIG ET AL. 1993).