| Author | Apichit Therdyothin |
| Call Number | AIT Diss. no. ET-92-1 |
| Subject(s) | Cogeneration of electric power and heat--Thailand
|
| Note | A dissertation submitted in partial fulfillment of the requirements for the Degree of Doctor of Engineering, school of Environment, Resources & Development |
| Publisher | Asian Institute of Technology |
| Abstract | The cogeneration potential of sugar mills in Thailand has been studied. Models of the
, existing sugar mills developed show that the excess bagasse ·is 12 % of produced bagasse or 1.02
million tons which can generate approximately 214 GWh of electricity. To achieve more excess
bagasse, four energy conservation opportunities, e.g. boiler excess air control, bagasse dryer,
condensation heat recovery of flue gas and use of thermo-compressor in multiple effect evaporator
have been studied. The results show that the total excess bagasse potential is about 28 % of produced
bagasse.
Four alternatives have been considered to increase the electricity generation potential from
excess bagasse. These are use of bagasse dryer, use of cane tops and leaves, use of high pressure
boiler with single extraction-condensing steam turbine (SECST) and use of high pressure boiler with
double extraction-condensing steam turbine (DECST). The estimated costs of electricity generated
from these four alternatives are 1.23, 2.80, 7.28 and 7.08 C/kWh respectively.
To select the most suitable alternative that gives the maximum benefit to the country not, only
financial factor is considered but also the impacts on environment and the society. The analytic
hierarchy process (AHP) has been used to select the best alternative based on following criteria i)
Government investment, ii) Private investment, iii) Total operating cost, iv) S02 emission, v)
Employment generation, vi) Availability of local equipment, and vii) Dependency on foreign
assistance. The result of five decision makers from five related organization in Thailand show that
SECST and DECST system are the best alternatives due to their very low government investment and
S02 emission.
For maximum financial benefit to the sugar mills which apply SECST and DECST systems,
the proper size of boilers and turbo generators must be selected from the commercially available
equipments. Using mixed integer linear programming technique, the optimum size of the boilers and
turbo generators have been selected for small, large and very large sager mills. The annual benefit
of small, large and very large size sugar mills, if proper SECST system is used, is 1.3, 2.4 and 4.6
million US$ respectively while the benefit is 1.9, 4.4 and 6.4 million US$ respectively if DECST
system is used. |
| Year | 1992 |
| Type | Dissertation |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Energy and Climate Change (Former title: Department of Energy, Environment, and Climate Change (DEECC)) |
| Academic Program/FoS | Energy Technology (ET) |
| Chairperson(s) | Bhattacharya, Sribas C. ;Surapong Chirarattananon |
| Examination Committee(s) | Tabucanon, Mario T. ;Prida Wibulswas ;Williamson, A. G.
|
| Scholarship Donor(s) | Government of Japan; |
| Degree | Thesis (Ph.D.) - Asian Institute of Technology, 1992 |