Retrofit example of cooling tower in a fire power plant

A) sewage cooling tower Renovation Project Overview:

The steam turbine Workshop of a thermal power plant has 2 counter-current FRP 800 tons of sewage cooling tower, which has been running for 10 years continuously since its completion. Due to the influence of production environment, the cooling water has high alkali content and poor water quality, and it is aging with long-term use of the equipment. Causes its rotating water-type cloth to appear the blockage, the corrosion and so on phenomenon, difficult to function normally. In order to meet the requirements of production, the company on the thermal power plant sewage Cooling tower effluent temperature and circulating water demand higher. After study, we finally decided to change the water system of 2 sewage cooling towers.

(ii) The status and problems of the cooling tower in the thermal power Plant 1, the basic situation of the sewage cooling tower

Cooling tower type: Ling Ke lkn-800l/sa;
Cooling cycle Volume: 640m3/h;
Cooling tower Inlet temperature: 42 ℃;
Cooling tower Effluent Temperature: 37 ℃;
Wind Type: direct-linked reducer fan forced ventilation
Water distribution system: Rotary water-cloth fiberglass cloth pipe
Filler Type: Ramp-type water-sprinkling filler

2. Problems existing in sewage cooling tower

As the sewage cooling tower of the thermal power plant circulating water for the production of sewage, water containing a large amount of alkali, water quality is poor, cloth water pipe and nozzle prone to clogging, rotary water-type cloth for a long time operation is easy to lead the bearing necrosis and stop running, resulting in cooling tower water area reduced, the dispersion efficiency is poor. In addition, the local leaching of water will lead to the filling is blocked by alkali, accumulate too much debris and cause the collapse of the filler, resulting in uneven distribution of gas and water or short-circuit water. The above-mentioned phenomenon in the cooling tower of the thermal power plant makes the cooling tower's cooling efficiency decrease obviously and can not meet the production requirements.

(iii) The target of renovation and transformation of water cooler

Improve the use efficiency of the sewage cooling tower in thermal power plant, ensure that the water-sprinkling device is evenly distributed, without changing the main structure of 2 800-ton sewage cooling tower, the cooling tower effluent temperature is reduced from 37 ℃ to 32 ℃. Meet the production requirements, to achieve the purpose of energy saving and consumption.

Technical transformation measures

There are many factors that influence the heat exchange efficiency of the cooling tower of the thermal power plant, but the uniformity of the water distribution is the most widely affected factor. Therefore, the modification of the sewage water cooling system will affect its cooling effect.

The modified cloth water system uses fixed type, the main road uses 108 carbon steel pipe, the pipe uses 5O galvanized pipe, the short joint installs the three splash type sprinkler, by the original center water pipe Flange Connection fixed type cloth water system. This transformation uses the ABS integral injection molding three splash type sprinkler head as the splash device, the intensity is high, is not easy to clog, the spray disperses evenly, is advantageous to the water vapor exchange. Each tower consists of 6 cloth pipes. After the steel is processed, the anticorrosion measures of hot galvanizing are adopted, and the galvanized coating is coated with two epoxy bitumen paints. The gap between the tube end and the inner wall of the tower is 25m. The three-splash nozzle is 50cm from the filler clearance. The h28-type pultruded FRP bracket is used to make the grid integral frame as the supporting layer of the water-collecting device. The characteristic of stationary water-distribution system is: the diameter of the water pipe is large. The fixed spray point is arranged evenly, so it is not affected by water quality, it is not easy to jam, and the cloth water is uniform. After the transformation, the water collector adopts FRP water collector, which has the characteristics of small resistance, high water collecting rate, corrosion resistance and so on, which effectively reduces the water replenishment.

(four) The effect of the water cooling tower in the thermal power plant after its transformation

• After the transformation of the two sewage cooling towers in the thermal power plant, the operation is good, the single tower treatment water is increased obviously, the water is uniform, the density is large, and the water drops into a drip-like position. After the operation comparison, after the overhaul compared to the pre-service single tower treatment water from the original 640m3/h, increased to 800m3/h, cooling tower effluent temperature from the original 37 ℃ reduced to about 32 ℃, fully meet the power plant turbine workshop production of water supply requirements.
• After the modification of the water cooling system to the fixed type, the nozzle and the cloth pipe are threaded to facilitate disassembly and can be cleaned quickly once a blockage occurs. Moreover, there is no bearing on the fixed-type water-distribution device, no rotating parts, almost impossible to fail, and can save a lot of maintenance cost every year.
• The operation period of the sewage cooling tower of the thermal power plant is prolonged. It avoids fouling, clogging and regular replacement of the filler in the cooling water system, which greatly prolongs the operation cycle.

Retrofit example of cooling tower in a fire power plant