FOCUS : TECHNOLOGIES FOR INFORMAL PROCESS INDUSTRIES

Project: Fuel-efficient design & development / modification of Citronella Oil Distillation Units in the South Western Ghats Landscape

Funded By: World Wildlife Fund (WWF)

Duration: August 2008 til Date

The practice of Citronella oil distillation is being followed by the residential Adivasi community of the Western Ghats since the past five decades. The process of oil distillation uses a steam generation unit and a condenser. The steam generation unit consists of a shell with an inlet to feed water and dried citronella grass, while the heat is passed through the bottom of the shell, the heat will steam the water in the drum and steam is passed through the grass. The oil extracts from the grass are collected and carried along with the steam. This subsequently passes through the condenser chamber, where the steam is cooled and liquefied, and eventually the oil and water are separated in a fractional distillation drum.

The conventional method of oil distillation involves traditional practices and there is no technological intervention to check oil quality or fuel savings. The Adivasi community works with a small margin and hence a cost effective technology was developed by TIDE in order to attain better output for the same grass capacity and reduced fuel combustion through a more friendly practice. Since the development of the improved technology, the livelihood of the Adivasi community has been enriched. They get more value for the citronella oil produced, due to improved oil quality with reduced carbon content, and the process of charring grass in the shell has been completely eliminated.

The improved steam distillation unit has five parts:

• The steam generation unit with an insulated combustion chamber
• The pre-heater which also acts as a pre-condenser
• The heat exchanger
• The carbon filter
• The main condenser

The device is designed according to the conventional device, so as to not divert the user from his accustomed user practice. The reduced fuel usage results in less drudgery to the people in collecting biomass, while increased yield for the same grass quantity results in more income for the same labor input and efforts. The citronella oil yield increased by 40%, the biomass saving was upto 50% for the same unit capacity and the quality of the oil was found to be superior using the improved device.