Vinasse application to sugar cane fields. Effect on the unsaturated zone and groundwater at Valle del Cauca (Colombia)

Abstract

Field assessment of vinasse application in sugarcane fields  Vinasse transport was assessed in vadose zone and aquifer  Major ions were efficiently retained due to vadose zone processes and plant uptake 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 *highlights Click here to view linked References AbstractExtensive application of vinasse, a subproduct from sugar cane plantations for bioethanol production, is currently taking place as a source of nutrients that forms part of agricultural management in different agroclimatic regions. Liquid vinasse composition is characterised by high variability of organic compounds and major ions, acid pH (4.7), high TDS concentration (117,416-599,400 mg L -1 ) and elevated EC (14,350-64,099 S cm -1 ). A large-scale sugar cane field application is taking place in Valle del Cauca (Colombia), where monitoring of soil, unsaturated zone and the aquifer underneath has been made since 2006 to evaluate possible impacts on three experimental plots. For this assessment, monitoring wells and piezometers were installed to determine groundwater flow and water samples were collected for chemical analysis. In the unsaturated zone, tensiometers were installed at different depths to determine flow patterns, while suction lysimeters were used for water samples chemical determinations. The findings show that in the sandy loam plot (Hacienda Real), the unsaturated zone is characterised by low water retention, showing a high transport capacity, while the other two plots of silty composition presented temporal saturation due to La Niña event (2010)(2011). The strong La Niña effect on aquifer recharge which would dilute the infiltrated water during the monitoring period and, on the other hand dissolution of possible precipitated salts bringing them back into solution may occur. A slight increase in the concentration of major ions was observed in groundwater (~5% of TDS), which can be attributed to a combination of factors: vinasse dilution produced by water input and hydrochemical processes along with nutrients removal produced by sugar cane uptake. This fact may make the aquifer vulnerable to contamination.

Combination of chemical coagulation, photo-Fenton oxidation and biodegradation for the treatment of vinasse from sugar cane ethanol distillery

“…The distillation of sugarcane juice and molasses to produce ethanol generates large quantities of vinasse: about 10e14 L per litre of ethanol produced (Júnior et al, 2015;Orteg on et al, 2016). This effluent is characterized by strong brown colour, acidic pH, high turbidity, high content of organic compounds (acids, alcohols, aldehydes, ketones, esters and sugars) that contribute for its chemical oxygen demand (COD) and biochemical oxygen demand (BOD 5 ), and high concentration of ions (K þ , Ca 2þ , Mg 2þ , Fe 3þ , Cl À and SO 4 2À ) (Barrera et al, 2013;Christofoletti et al, 2013;Marinho et al, 2014;Orteg on et al, 2016). As vinasse presents high organic matter and nutrient contents, it has been common practice to use it as fertilizer in sugarcane fields (Júnior et al, 2014;Moraes et al, 2015).…”

Assessing the Impact of a Vinasse Pilot Plant Scale-Up on the Key Processes of the Ethanol Supply Chain

“…For instance, vinasse has been widely used to generate biogas from anaerobic digestion [4,9,10]. Similarly, it has been employed as a fertilizer for sugar cane fields, although the main problem with this is that a portion of vinasse may infiltrate into the soil and damage aquifers [11][12][13][14][15][16]. In addition, Colin et al [17] and Sankaran et al [18] used bacteria to retrieve effluents generated from the ethanol industry, while Akram et al [10] assessed the potential of vinasse for biofuels production.…”

Water Flow Path Characterization in Shallow Vadose Zone Using Tensiometers

“…As in [6] the authors installed Tensiometers in the unsaturated zone, at different depths to determine flow patterns, while suction Tensiometers were also used for water sample chemical determinations. Their findings show that in the sandy loam plot (Hacienda Real), the unsaturated zone is characterized by low water retention, showing a high transport capacity, while the other two plots of silty composition presented temporal saturation due to La Niña events (2010-2011) [6]. Traditionally, a Tensiometer is installed in the soil to measure the amount of actual evapotranspiration, which is released by plants.…”