Ranking of Vinasse mulches in terms of environmental indicators using TOPSIS model (Case study: North of Khorramshahr)

Today, due to the negative effects of oil mulches on the environment, has attracted a lot of attention the use of environmentally friendly mulches. The purpose of this study is to determine the best combination of vinasse, filter cake, bagasse and bagasse ash as mulch in terms of environmental indicators in the north of Khorramshahr. In this study, 81 treatments were provided with combination of vinasse (0, 100, 200 g), bagasse (0, 25, 50 g), ash bagasse (0, 25, 50 g), filtercake (0, 12.5, 25 g) and one-liter water. In the first step, among 81 treatments, were determined treatments in the appropriate range of salinity and acidity and in the second step, after mulching (35 optimal treatments in the first step) on laboratory trays (2×30×100 cm), have been measured shear strength, compressive strength, impact resistance, surface crack coefficient for optimal treatments with at least three replications. In the third step, the selected mulches are qualitatively scored. In the fourth step, the selected treatments in the previous step are examined in terms of the indicators of heavy elements (cadmium, chromium, lead, zinc, arsenic, mercury, vanadium, nickel), salinity, acidity and chemical properties (calcium, magnesium, sodium, sulfate, chlorine, phosphorus, (Potassium, organic carbon, nitrogen and sodium uptake ratio). In the last step, the treatments were ranked in terms of environmental indicators using the TOPSIS model and the treatment with the highest proximity index was selected as the optimal mulch. The results of TOPSIS model showed that treatment 19 (100 g vinasse, 50 g bagasse, no ash bagasse and 12.5 filter crack) with a proximity index of 0.89 was the first. Based on the results of this study, it can be concluded that the use of vinasse (100 g) in the optimal treatment will increase the rank of vinasse mulch in terms of environmental indicators with a proximity index of 0.89 and on the other hand, The presence of bagasse and filtercake in the optimal mulch has a significant effect on increasing the shear strength (up to 2 kg / cm2 compared to the control) and reducing the crack coefficient (up to 1.8% compared to the control).