A comparision of energy balances in pulp mills using different raw materials | |
| Author | Adhikari, Yuba Raj |
| Call Number | AIT Thesis no.PP-02-3 |
| Subject(s) | Bioenergetics Pulp mills Energy consumption Sulphate waste liquor |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering. |
| Publisher | Asian Institute of Technology |
| Abstract | Pulp and paper production is among the most energy intensive segments of all industries. Modern chemical pulp mills are energy self-sufficient, and often can generate excess steam and electricity. Black liquor is an integral part of the standard pulping process, which is burnt primarily to recover the chemicals present in the liquor. About 50% of the pulping raw materials, a useful biomass, go to black liquor, which under incineration gives out energy. The black liquor composition, properties and amount depend upon the pulping method employed and different pulping parameters. This study comparatively analyzed the potential of black liquor in energy balances of the pulp mills using different raw materials. Major pulping performances of the different raw materials were also studied and the complete black liquor analysis has been performed. Then, a black liquor fired cogeneration system model in the use of recovery boiler was developed and its role in energy balance of the mill was evaluated. The cogeneration system gave a surplus of electricity satisfying all heat and electricity demand of the mill in case of pulping of eucalyptus. There was a great deficiency of steam and electricity for the pulp mills using bagasse as raw material. Bamboo mill satisfied well the heat demand but there was a small deficiency of electricity. Better HHV, a measure of quality of fuel potential was obtained for the liquor containing lesser presence of inorganics and higher dissolving particles of raw materials in the liquor. A sensitivity analysis in energy balance carried out for bagasse pulping using energy efficient scenarios showed that an energy efficient technology enables the bagasse pulp mill to fulfill its heat demand but deficiency in electricity is always likely to occur because of lesser black liquor output. Bamboo pulping mill showed its performance nearer to eucalyptus than bagasse. |
| Year | 2002 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Food, Agriculture and Natural Resources (Former title: Department of Food Agriculture, and BioResources (DFAB)) |
| Academic Program/FoS | Pulp and Paper Technology (PP) |
| Chairperson(s) | Ruhanen, Mauno; |
| Examination Committee(s) | Bhattacharya, Sribas C.;Kolehmainen, Heikki; |
| Scholarship Donor(s) | Government of Finland;Asian Institute of Technology; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2002 |