renewable energy applications in jaggery industries - erg 591 credit seminar (0+1) - dec- 2011 -...
TRANSCRIPT
Chairman StudentDR.M.SINGARAVELU, C.Vijayanand,Professor , M.Tech II yearDept. of Bio-Energy , Dept. of Bio-Energy,AEC & RI TNAU. AEC & RI TNAU.
MembersDR.N.O.GOPAL, DR.V. THIRUPATHI,Professor, Associate Professor ,Dept. of Bio-Energy, Dept. Of Food & AgriculturalAEC & RI TNAU. process engineering,
AEC & RI TNAU.
Jaggery, commonly known as ‘gur’ in India is a traditional, non-refined and centrifugal sugary material
Jaggery is a condensed form of sugarcane juice produced by evaporation of moisture
Sugarcane after harvest to unit
The power consumption for a 5 H.P. roller crusher is 35 units to crush 100 kg of sugar cane
The bagasse is dried and used as fuel for jaggery production
Specific fuel consumption from 1.5 to 1.75 tons bagasse per ton of jaggery
However the quantity of bagasse available is not sufficient for jaggery production
The use of firewood as fuel is carried out when adequate bagasse is not available
The current methods under practice are very low in thermal efficiency
High amount of heat is lost in these processes followed at present
1. Poorly built heating furnaces and chulhas which supply inadequate air supply resulting in incomplete combustion
2. Heating pans for boiling sugarcane juice are inefficient, giving uneven heat transfer
3. Excess fuel supply, replacement of bagasse by firewood, rubber tyres
Use of improved chulhas or furnaces for complete combustion of bagasse or firewood
Use of solar drying technologies for drying and condensing of jaggery
Use of agro residue fuels like briquettes
Improved design of jagerry heating chulhas and furnaces for greater thermal efficiency
Jaggery plants are generally constructed by local artisans
It mainly consists of an underground furnace, like an open cooking stove, (bigger version of a biomass based cooking stove) with a pan mounted on to it for evaporating the juice
There are different types of jaggery furnace, single pan furnace and multiple pan (three to four pans) furnace
In a single pan furnace all jaggery making processes like sensible heating, chemical addition, impurity removal, evaporation etc. are carried out
In a single pan as a batch process while in a multiple pan furnace above jaggery making processes are carried out in three to four pans in a semi continuous mode
For performance evaluation of a jaggery furnace it is essential to establish mass and energy balance
The mass balance study in jaggery processing starts with the measurement of the crusher performance
A known quantity of cane is crushed
The dried bagasse with moisture content of 8-10% is used for firing in the furnace
Jaggery produced per batch is measured
The measurement of mass of bagasse fired and mass of jaggery produced in a batch represent the performance of furnace
The measurement of oxygen, carbon monoxide and temperature in flue gas in the furnace chimney is used for thermal analysis
The input streams for jaggery furnace consist of juice, combustion air and bagasse
The output streams are flue gas, liquid jaggery, water evaporated from juice and wall loss from furnace
The mass and energy balances then calculated for fuel feeding rate for controlled feeding and normal fuel feeding
Conventional multi pan chulha
Improved 4 pan chulha/furnace
Unit – MJ/h
Particulars
Heat supplied MJ/h
Heat utilized MJ/h
Heat loss MJ/h
Thermal efficiency
Type of feeding
Present feeding
Control feeding
Present feeding
Control feeding
Present feeding
Control feeding
Present feeding
Control feeding
Unit in
MJ/h
2846 2055 813 813 2033 1242 40% 65%
The reduction in the fuel quantity by just controlling the fuel feeding rate is about 33 to 28%. The saving in the fuel is mainly on account of reduction in flue gas temperature from 900 to 700 deg C and reduction in unburnt loss
The specific bagasse consumption is reduced from 1.73 kg bagasse/kg jaggery to 2.39 kg bagasse/kg jaggery, this leads to reduction of 0.66 kg bagasse/ kg jaggery
Hence the controlled fuel feeding in the four pan furnace is more energy efficient process than the regular feeding of fuel
As the efficiency of the process is increased from 40% to 65 %
The graphs indicate that the rate of drying of jaggery increases rapidly with the forced convection mode than natural mode
The experimental study reveals that the rate of drying of the jaggery samples of different sizes was greater in forced convection than natural convection
However the cost of solar drying will be 40% more than the conventional drying using moulds ( wooden or clay)
Solar drying of jaggery reduces caramelisation and improves jaggery color and quality
Apart from these solar preheating of sugarcane juice can prevent the loss of sucrose upto 4%
A study was conducted for the improvement of efficiency of jagerry open pan furnace.
A regular flat bottom main pan, gutter pan and modified pan , gutter with fins at the bottom were taken with sugar syrup for jagerry production.
The increase in area of heat receiving surface due to fins was calculated as:
Increase in area = 2 total length of flat provided
X width of flat
The heat transfer was observed to be high in the modified jaggery pan and gutter pan
The bagasse consumption for the conventional pan was higher than that of the improved/modified
The average annual growth of sugarcane in agriculture sector is 2.6% against the overall growth of 3% in the agriculture sector of India
20 to 25 % of the total sugarcane harvested goes into the making of jaggery
With this rapid increase of sugarcane production, jaggery production is subjected to increase
The energy efficient methods involving improved chulhas, furnaces can be utilized in jaggery production
The use of biomass derived fuels like briquettes can make a significant difference in jaggery production
Use of solar energy technologies for preheating of sugarcane juice and drying of jaggery
By implementing renewable energy technologies and energy efficient methods higher thermal efficiencies can be achieved
Hence renewable energy and energy efficient methods adoption will increase the output of Jaggery industry
Vishal, Pillai I.R. Thermal performance evaluation of a four pan jaggery processing furnace for improvement in energy utilization.
Pattnayak P.K,. Misra M.K. Energetic and economics of traditional gur preparation: a case study in Ganjam district of Orissa, India. Department of botany, berhampur University, berhampur, Orissa, India.
Tiwari G.N, Sanjeev Kumar, Om Prakash. Evaluation of convective mass transfer coefficient during drying of jaggery. Center for Energy Studies, Indian Institute of technology, New Delhi 110016, India
S.I. Anwar. Fuel and energy saving in open pan furnace used in jaggery making through modified juice boiling/concentrating pans. Division of Agricultural Engineering, Indian Institute of Sugarcane Research, Raebareli Road, Lucknow 226 002, UP, India.
Anil kumar, Tiwari G.N. Thermal modelling and parametric study of forced convection green house drying system for jaggery. Department of industrial and production, University institute of technology, Rajiv Gandhi technology university Bhopal, India.