Application of the hottest closed high temperature

  • Detail

Application of a sealed high temperature condensate recovery system

classification No.: tk264.1 document identification code: b

Article No.: 1001 - 2060 (2000) 02 - application of a sealed high temperature condensate recovery systemxia li

(Yunnan Zuxun tobacco leaf roaming factory) Abstract:Described in this paper are the use-effectiveness of a sealed high-temperature condensate recovery system as well as some test results and use-experience.

key words: high-temperature condensate, recovery system, energy savings ▲ 1 preface

closed high-temperature condensate recovery technology is a waste heat recovery technology that directly pumps high-temperature condensate into the deaerator or boiler without heat exchange and cooling

the size of 2 SHL samples used by our factory is small to the diameter φ The 0.005mm gold wire 3- II boiler is used in three tobacco redrying workshops to increase the capacity of acrylic resin for optical materials. In August, 1993, our factory popularized and applied the closed steam condensate recovery system and high-temperature condensate recovery device. After putting into use, the test shows that the effect is good, the energy saving rate is 28.77%, and the annual saving is about 3101.4 tons of standard coal. 2 working principle

the process flow of the recovery system is shown in Figure 1. The system includes a high-temperature condensate recovery device, a water collecting tank, several pipelines, accessories and electrical automatic control cabinets, but any equipment has been used for a long time. 1 - high temperature condensate in workshops 1, 2 and 3 2 - water collection 3 - differential pressure transmitter 4 - liquid level gauge 5, 8, 11, 13, 15, 17, 18, 20 - stop valve 6 - filter valve

7 - thermometer 9 - check valve 10 - vent valve 12 - pressure regulating valve

16, 19 - recovery device 21 - pressure gauge 22 - stop, check valve 23 - silencing tube Figure 1 process flow diagram of recovery system 2.1 the main equipment of the system is high temperature condensate recovery device, as shown in Figure 2, It automatically pumps the high-temperature condensate in the water collecting tank into the deaeration tank or boiler. Unlike other recovery pumps, it can automatically discharge the gas (steam) in the pump. Fig. 2 high temperature condensate recovery device

the device is equipped with a set of jet booster at the pump inlet to avoid cavitation of saturated water at the pump impeller inlet in 2012. The injection pressurization device consists of 2, 3, 4 and 7. When the operation starts or the water pump finishes pumping water, air or water vapor is collected at the upper part of the water pump, the solenoid valve 3 will automatically act to exhaust (steam). After the exhaust (steam), the pipe will be filled with water, and the solenoid valve 3 will automatically close, return to normal state, and wait for pumping water

2.2 the water collecting tank is used to collect high-temperature condensate, flash steam and flash steam for expansion. It is equipped with a liquid level gauge and accessories, and leads out the pressure signal to the differential pressure transmitter for automatic system control

2.3 when the system works, as shown in Figure 1, the high-temperature condensate 1 from workshop 1, 2 and 3 enters the water collecting tank 2 by its own pressure. After flash evaporation, the flash steam and high-temperature condensate are separated from the water collecting tank. The flash steam enters the soft water tank through the check valve 9 and the pressure regulating valve 12 by its own pressure to heat the softened water. The high-temperature condensate without flash is collected in the water collecting tank 2. When the water level rises to the specified upper limit value (the water level signal is sent to the electric control cabinet by the differential pressure transmitter 3), the recovery device will automatically start. The high-temperature condensate enters the deaeration tank through circuits 6, 7, 8, 15, 16, 17 (or 18, 19, 20), 21, 22. When the water level drops to the lower limit value, the device will automatically stop, wait for the next pump, and automatically realize its own discharge (steam) process

if there is a large amount of condensate, the two units will start successively and operate at the same time. 3 test

the working conditions before the high-temperature condensate enters the water collecting tank are complex, and the steam water ratio is difficult to measure. The working parameters such as pressure and temperature after entering the tank are easy to measure. The condensate flow can be measured by using the average flow of condensate collected in the water collecting tank. The rest tests are as follows:

3.1 flash steam flow

maintain a certain water level in the soft water tank, i.e. neither water nor water, and flash steam is introduced, as shown in Figure 3, The heat loss is approximately 0. Within a certain period of time, there are:

g1 × (h1-h0)=Cm × (m0+G1) × (t2-t0)

then: G1 = M0 (t2-t0)/[(h1-h0) -cm (t2-t0)]

in Figure 3, G1 - flash steam flow, kg/h; H1 -- enthalpy of flash steam before entering soft water (P1, T1), kj/kg; H0 -- enthalpy of condensate in test termination state (P0, T2), kj/kg; Cm -- specific heat of softened water, 4.1868 kj/(kg. ℃); M0 - mass of water in water tank before test, kg; T2 -- softened water temperature at the end of the test (85), ℃; T0 -- softened water temperature at the beginning of test (54), ℃

3.2 recovered waste heat

assuming that the effective utilization coefficient of high-temperature condensate entering the deaeration tank and soft water tank is 0.95, the recovered waste heat

q=0.95 ×[ G1 (h1-h2) +g2 (h0-h2)]

where: Q - effective heat energy recovered by the system, kj/h; H1 -- flash steam enthalpy in recovery state (P1, T1), kj/kg; H2 -- enthalpy of condensate at ambient temperature (22 ℃), kj/kg; H0 -- enthalpy of high temperature condensed water in recovery state (P1, T1), kj/kg; G1 - flash steam flow, kg/h; G2 - condensate flow, kg/h

3.3 energy saving rate

η′=[ q/(h3-h2)D ×η]× 100%

where: H3 -- enthalpy of main steam outlet, kj/kg; H2 -- enthalpy of condensate at ambient temperature (22 ℃), kj/kg; D - during system test, the boiler total

Copyright © 2011 JIN SHI