Montenegro: Selection of technology and boiler for the new TPP Pljevlja unit, bidders evaluation in progress

, SEE Energy News

Advantages and disadvantages of two technologies are defined by analysis of various parameters . Selection of the boiler type and coal combustion technology for unit II of Thermal Power Plant “Pljevlja” of power (220 ÷ 300) MW were assessed by TPP engineers within the evaluation of the bidders for the construction of the new unit.

Two coal combustion technologies – Benson flow boiler or boiler on natural circulation with drum and firing in coal dust and boiler on natural circulation with drum and coal combustion in circulating fluidized bed were discussed in this expert work.

Alternative technical possibilities of building unit II in TPP “Pljevlja” were selected in the conceptual solution of the first stage of documentation draft. Possible variants of the unit power in the range of 220MW to 600MW were examined. Coal reserves, and the ability to transport heavy plant components to Pljevlja for units 450 and 600MW are the main factors of optimal power choice of unit II.

Examining the available coal reserves of Pljevlja basin, selected power of (220÷300) MW is the optimal value. A coal mixture from various mines basin of Pljevlja is the primary fuel of the new unit, which must conform to the requirements and conditions for environmental protection according to the regulations of Montenegro and the European Union.

For both variants were discussed units efficiency, steam parameters and feed water, the reduction of NOx, flue gas desulphurization, operating characteristics, erosion and fraying of exchange surfaces, investment costs, maintenance costs, and references.

After a technical description and main boilers characteristics, the authors note that boilers with circulating fluidized bed meet the BAT recommendations in terms of efficiency, while the efficiency is about two percent lower in the case of the boilers on coal dust. The difference is not large, and in terms of technology choice investor needs to make a decision.

Fluidized bed boilers have advantages in the reduction of NOx, the outlet temperature of flue gases, combustion efficiency over 99 percent, reducing the possibility of furnaces ash slugging, investment costs, necessary area for the construction, operational flexibility to change the coal quality and biomass combustion options.

On the other hand, boilers on coal dust have the advantage in effects of flue gases desulphurization, use of cement in the construction industry, time to move from cold state, references and staff experience in handling boilers with PC technology.

Considering the above criteria, if BAT recommendations are strictly respected, which are generally designed for higher power units, it will be better to choose a boiler with circulating fluidized bed. In reviewing the conceptual designs of building new units in the thermal power plants in the surroundings, the priority is given to CFB technology. However, since it is a thermal power plant with power of 220 to 300 MW, other criteria also should be well evaluated, as cost and way of financing and should be made decision for a more favorable technology.

Source; Serbia Energy See Desk