Issue 6 - faculty.ait.ac.th - Asian Institute of Technology

Energy Use and Pollution in the Tea Industry
Energy-Environment Highlights
Energy and environmental audit in tea factories have been conducted within the framework of the project “Small and Medium
Scale Industries (SMIs) in Asia: Energy, Environment and Climate Interrelations. This issue presents some results of energy use
and pollution in the audited tea factories in Sri Lanka and Vietnam.
Sri Lanka
Sri Lanka is the world’s largest exporter of black tea and produced about 280 million kg of tea in 1998. The land under tea cultivation
is about 189,000 hectares. The tea produced in Sri Lanka is mainly of orthodox type (more than 93%) and the remaining is
the CTC (crush, tear and curl) type. At present, there are 634 factories operating in Sri Lanka providing employment to about
650,000 people including those who are engaged in cultivation. It is estimated that around 100,000 personnel are employed in
factories.
Table 1. Specific Energy Consumption and Emission Produced in three Sri Lankan Tea Factories
High Grown Mid Grown Low Grown
Table 1 pre- Category
sents the specific
energy conand
electricity)
the three tea
Specific energy
consumption
Thermal (kWhth/kg)
Electrical(kWhe/kg)
7.4
0.61
5.28
0.56
6.23
0.48
sumption (thermal
and emission in
producing regions.
CO2 (kg/kg of product)* 1.1 a
Specific emission
Vietnam
Region
Tea is grown mainly in the northern provinces of Vietnam and in Lam Dong Province in the South. There are 75 state-owned
tea processing bases in the country of which 30 belong to the Vietnam National Tea Corporation. There are also more than
1,200 non-state small-scaled enterprises and tens of thousands of households involved in processing tea. The two main kinds of
tea products of Vietnam are black tea and green tea. Technologies used in producing black tea are Orthodox and CTC, while
Chinese, Taiwanese, Japanese and traditional Vietnamese technologies are used in producing green tea.
Figure 1 presents the specific energy consumption in two black tea factories along with the benchmarks set by National Tea
Corporation, Vietnam.
Specific thermal energy consumption
(kWhth/kg of product)
20
18
16
14
12
10
8
6
4
2
0
Figure 1. Specific Energy Consumption in Two Vietnamese Tea Factories
4 SMI Newsletter, July-September 2000, Volume 2, No. 3
2.7 b
SO2 (kg/kg of product) 0.03
Note: *These are based on audits conducted in three factories
a Energy use for withering and drying is from one furnace; b Two furnaces serve for withering and drying separately
17.3
11.3
Factory A Factory B
(a) Specific thermal energy consumption
Benchmark
Specific electricity consumption
(KWhe/kg of product)
0.6
0.5
0.4
0.3
0.2
0.1
0
0.4
(b) Specific electricity consumption
0.5
Factory A Factory B
Tea
Benchmark