Liquid Level Switches for NO.3 Shanghai Waigaoqiao Power Plant

深圳计为自动化技术有限公司

Shenzhen Jiwei Automations Ltd.

Shanghai Waigaoqiao No.3 Power Plant: A Model of Clean Coal-Fired Power Generation

Liquid level switches are crucial for accurate and reliable liquid measurement in industrial environments. At the Shanghai Waigaoqiao No.3 Power Plant, Jiwei’s Ring-11 liquid level switch has been instrumental in ensuring the safe operation of high-pressure systems, particularly in the power generation process.

Shanghai Waigaoqiao No.3 Power Plant is located in Pudong New Area, Shanghai. It is the third phase expansion project of Shanghai Waigaoqiao Power Plant and is known as the cleanest coal-fired power plant in the world.

Thermal power generation generally refers to the use of oil, coal, natural gas and other fuel combustion heat to heat water, so that water is put into high temperature, high pressure steam, and then steam driven generator to generate electricity. The thermal system of the power plant consists of boiler, steam turbine and its auxiliary equipment connected by pipes and accessories according to the steam water cycle process.

Shanghai Waigaoqiao No.3 Power Plant

Condensate Water Treatment and Heating Process in Thermal Power Generation

In a thermal power generating unit, condensate water is sent to low-pressure heater by the condensate pump, which is heated by the extraction steam from low-pressure cylinder of steam turbine, and then sent to the deaerator.

At this time, 160 ℃ saturated water is sent to high-pressure heater by feed water pump after being deoxidized by the deaerator. The super heated steam extracts from the high-pressure cylinder of the steam turbine is used as the heating medium, and finally flows into the boiler to be lifted again by economizer. When temperature is high, water that enters the drum can obtain a considerable amount of heat in advance, so the heat transfer area required to reach the degree of vaporization can be slightly reduced when circulating heating in the furnace tube.

Reliable liquid level switches ensure boiler efficiency, steam control, and safety

To ensure the normal operation of boiler, it is necessary to measure the liquid level by reliableLiquid Level Switch, so as to balance the water supply, maintain the water level of steam drum, ensure the steam quality, control the steam pressure and temperature, reduce the heat loss and improve the thermal efficiency of boiler.

The high water temperature of this thermal system and the high temperature and high pressure working ambient put forward higher requirements for the Liquid Level Switch. In order to find a suitable Liquid Level Switch, the client has tried to compare various level switches.

Overcoming High-Pressure Challenges with Jiwei Ring-11 Liquid Level Switch

Among various liquidlevel measuringinstruments, the guided wave radar level meter meets the requirements, and has great stability and accuracy, but it is rarely used because of the high expense. Moreover, due to the changing density of high temperature and high pressure water, density correction becomes a significant problem. Some common Liquid Level Switches in the market cannot adapt to this high-pressure environment with the poor sealing technique.

Besides, the false alarms problem also seriously affects the production efficiency. Although imported level switches are reliable, the expense is extremely high. Finally, the client finds Jiwei Ring-11 Liquid Level Switch. As an efficient and cost-effective liquid level measurement instrument, Ring-11 Liquid Level Switch has high pressure protection features while the quality and performance were comparable to imported products.

Ring-11 High-pressure Liquid Level Switch

Firstly, the high-pressure protective gas-tight leadthrough of Jiwei Ring-11 High-pressure Protection Liquid Level Switch is the glass-metal encapsulation connector that configures between process connection and meter head.

The sealing effect is achieved by the cooperation of borosilicate glass and stainless steel, which prevents the fork body from penetrating under high temperature and high pressure in the long run, and prevents the high temperature liquid from penetrating into electronic module of the meter head through addition pipe and process connection, and also prevents the occurrence of flushing out housing leading to the accidentally leakage. In addition, the high-pressure gas-tight leadthrough can also protect the piezoelectric components from moisture.

Ring-11 High-pressure Liquid Level Switch is equiped with gas-tight leadthrough

Secondly, besides the above characteristics, the electronic part of Ring-11 High-pressure Liquid Level Switch has been modularized. The whole circuit board is installed in a half cylinder plastic box. At the same time, pouring sealant is injected into the case to prevent electronic material from oxidizing, thus achieving a better sealing and insulation effect. That is to say, the electronic modular is waterproof, anticorrosive and insulating, it greatly improves the instrument reliability, extends the service life and simplifies the maintenance while users can just directly replace the circuit module.

The electronic part of Ring-11 High-pressure Liquid Level Switch has been modularized

Thirdly, Ring-11 is specially made of 316L stainless steel with aluminum alloy meter head, which enables the instrument to be used in a corrosive environment. In order to adapt to the complex working conditions of high temperature and strong corrosive liquid level, the special setting of high-pressure protective gas-tight leadthrough makes Ring-11 High-pressure Liquid Level Switch effectively prevent accidental leakage of high-pressure strong corrosive liquid.

More than that, the high-temperature extension tube can be chosen from ECTFE and PFA coating, so it is suitable for measuring the liquid level of hydrochloric acid, sulfuric acid, nitric acid, alkali liquor, syrup, liquid medicine and industrial waste water, and is especially suitable for high-pressure liquefied gas (such as LNG) and complex measuring occasions with bubbles, bubbles, viscous liquids and vibration interference.

With the excellent quality, design, techniques and ultra-high performance price ratio, Ring-11 High-pressure Liquid Level Switches have been widely applied in No.3 Power Plant of Shanghai Waigaoqiao.

文字 |Cathy

封面图 |丁工

英文翻译|阿凯

内容审核｜黄工

图片 |板栗