Case Study

An analysis was conducted for a Ramzin type steam generator P-56-1 built in the TPP Sisak. Two steam generators produce steam for a turbine comprising a 210 MW power block. The furnace (Fig. 1) of the boiler has dimensions of 8.4×8.4×25.1 m and enables thermal input of 300 MW. On each side-wall of the chamber, at height of approx. 5 m, there are two burners. Newly installed low-NOx burners NAB 68-GO (Fig. 2) consist of combustion air swirl generating register, steam atomizer and gas lances.

image208

Fig. 1. Discretization of the furnace.

The airflow is divided into two streams: the primary stream that is swirled by passing through the flame holder and the secondary stream, which is swirled by the tangentially arranged blades. The oil preheated to 120 °С at 12.5 bar is atomized into fine mist by steam at 18 bar in so called Y-nozzles (eighth openings) forming a hollow cone in front of the atomizer. Natural gas at 1.2 bar is fed through eight gas lances. Each lance, having 21 nozzles, is rotated relatively to the previous one, so that the outgoing gas flow from the burner would gain rotational component. Tables 1 and 2 give the composition of natural gas and heavy fuel oil, respectively.

image209

Table 1. Heavy fuel oil composition (elemental analysis).

mass%

vol%

c

85.02

37.74

H

11.65

61.64

N

0.17

0.06

0

0.17

0.06

s

3.00

0.50

Table 2. Natural gas composition.

vol%

CH4

96.59

C2H6

1.87

co2

0.46

n2

1.08

Leave a reply

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>