Leachate Characteristics of Vinasse Made from Sorghum Stem Juice and Molasses in the Columns of Several Clay-Textured Soils
Mohammad Nurcholisa)*, Eko Amiaji Yuliantoa), Sari Virgawatia), Fahmi Herwinastwan Prakosa a), Firdaus Muhammad Fauzi a), Faida Anisa Aviagab), Suhadic)

a)Master Program, Department of Soil Science, Universitas Pembangunan Nasional Veteran Yogyakarta, Indonesia
nurcholis[at]upnyk.ac.id
b)Bachelor Program, Department of Soil Science, Universitas Pembangunan Nasional Veteran Yogyakarta, Indonesia
c)Ethanol Factory, PT Madubaru, Yogyakarta, Indonesia

Abstract

Vinasse as a by-product of processing plant materials into bioethanol is a renewable energy source, which it can be obtained from sugar-producing plants. Vinasse contains nutrients and organic content that can support its use as liquid organic fertilizer on agricultural land in Indonesia. The aim of this research was to determine the leaching process of vinasse and the leachate results in various types of clay-textured soil. In this research, leaching process was performed to vinasse in columns of five types of clay-textured soil. There were five soil samples collected from the field, and then air-dried and sieved through a diameter of 2 mm. There were two kinds of vinasse, from ethanol production using sorghum stem juice as raw material and form molasses as waste of sugar industry, with control using distilled water. The leach column was constructed using PVC tube with a diameter of 11.4 cm and a height of 30 cm, and it was filled with 1 kg soil. The analyses carried out were leaching time, percent volume of liquid leached, pH, electrical conductivity (EC), Eh, chemical oxygen demand (COD), and biological oxygen demand (BOD). The results of this research showed that the leaching time of vinasse from molasses can reach 5 hours. The volume of vinasse leach from sorghum was the highest (>90%). The pH of the vinasse increased after passing through the soil column. The highest EC of the leached vinasse is from molasses, namely around 15 mS. The COD and BOD values of vinasse increased after passing through the soil column.

Keywords: bioethanol, leaching, liquid organic fertilizer, sweet sorghum, vinasse

Topic: Agriculture