良心柱塞泵厂

高压柱塞泵在线水冲洗技术在脱硝空预器上的应用

Application of on line water washing technology for high pressure plunger pump on denitration air preheater

1. 设备概述

1. Equipment Overview

1.1机组概述

Summary of 1.1 unit

盘山发电公司2×600 MW火电机组是我国华北地区建设投产最早的600 MW等级火电机组，工程于1998年10月开工，其中3号机组于2001-12-18正式投产，4号机组于2002-06-05日正式投产，是京津唐电网的主力机组。锅炉为哈尔滨锅炉有限责任公司制造HG-2023/17.6-YM4 型锅、亚临界压力、一次中间再热、固态排渣、单炉膛、Π型布置、全钢构架悬吊结构、半露天布置、控制循环汽包炉。采用三分仓回转式空气预热器，平衡通风， 6 套制粉系统为正压直吹式制粉系统，配置ZGM-123 型中速磨煤机。

The 2 x 600 MW thermal power unit of Panshan Power Generation Company is the earliest 600 MW grade thermal power unit in North China Construction and put into operation. The project was started in October 1998, of which unit 3 was formally put into operation in 2001-12-18, and unit 4 was formally put into operation on 2002-06-05 day, which is the main force of Beijing Tianjin Tangshan power grid. The boiler for Harbin Boiler Co., Ltd. makes HG-2023/17.6-YM4 type pot, subcritical pressure, once reheat, solid slag discharge, single furnace, layout, whole steel frame suspension structure, semi open layout, and control circular drum furnace. The three compartment rotary air preheater is used to balance ventilation, and the 6 pulverizing system is a positive pressure direct fired coal pulverizing system, which is equipped with ZGM-123 medium speed coal pulverizer.

1.2脱硝空预器改造概述

Summary of 1.2 denitrification air preheater

脱硝SCR反应器投运后，由于氨逃逸的存在，会加剧空预器中温段和冷端的腐蚀和堵灰。因此需要对下游的空预器在防止堵塞和冷段清洗方面作特殊设计和改造。改造范围主要包括：

After the denitration SCR reactor is put into operation, the ammonia escaping will aggravate the corrosion and ash blocking of the middle and the cold ends of the air preheater. Therefore, it is necessary to make special design and transformation for the downstream air preheater to prevent clogging and cold section cleaning. The scope of the transformation mainly includes:

1） 改造后总的换热面积由45032平米增加到47189平米，约增加4.8%；蓄热元件仍维持原来的三段布置，总高度由860mm增加到1910mm，增加约2.7%；

1) after the transformation, the total heat transfer area increased from 45032 square meters to 47189 square meters, with an increase of about 4.8%; the regenerative components still maintained three sections of the original, and the total height increased from 860mm to 1910mm, and increased by about 2.7%.

2） 改造后空预器的转动重量计算值（含驱动装置及顶部轴承箱、驱动轴等）由373.12吨增加为423.23吨，增加约13%；驱动电机功率由9KW增加至11KW；

2) the calculation value of the rotating weight of the air preheater (including the driving device and the top bearing box, the driving shaft, etc.) increased from 373.12 tons to 423.23 tons, with an increase of about 13%, and the driving motor power increased from 9KW to 11KW.

3） 热段元件采用高吹灰通透性的HS7板型替代原DU板型，高度由原来的780mm减少到300mm；

3) high temperature soot blowing HS7 plate is used instead of the original DU plate, and the height is reduced from original 780mm to 300mm.

4） 中温段采用利旧原中温段，保持HS7板型不变，高度780mm不变；

4) in the middle temperature section, we should use the old intermediate temperature section to keep the HS7 plate unchanged and the height 780mm unchanged.

5） 冷段层采用HS8板型脱碳钢度搪瓷表面传热元件，高度由原300mm增加到830mm。冷端采用搪瓷表面传热元件可以隔断腐蚀物（硫酸氢铵和由SO3吸收水分产生的H2SO4）和金属接触，而且表面光洁，易于清洗干净。搪瓷层稳定性好，耐磨损，使用寿命长；

5) the cold section uses HS8 plate decarbonization steel enamel surface heat transfer element, and the height is increased from original 300mm to 830mm. The cold end uses the enamel surface heat transfer element to cut off the corrosion (ammonium hydrogen sulfate and H2SO4 produced by the SO3 absorption of water) and metal contact, and the surface is smooth and easy to clean. Enamel layer has good stability, wear resistance and long service life.

6） 空预器热端新增加一台普通蒸汽吹灰器。冷端吹灰器采用双介质吹灰器，采用蒸汽/高压水做为吹灰介质，新增加一套以高压柱塞泵为核心设备的高压水泵系统两台空预器共用，设计上可以在线隔离/非隔离以及离线水冲洗。

6) an ordinary steam soot blower is added to the hot end of the air preheater. The cold end soot blower adopts a double medium soot blower, using steam / high pressure water as the soot blowing medium. A new set of high pressure plunger pumps is used as the core equipment of the high pressure water pump system two air predevices. The design can be online isolation / non isolation and off-line water irrigation.

1.3空预器高压水冲洗系统概述

A summary of high pressure water washing system for 1.3 air preheater

由于高压水射流集中，剪切强度大，对灰垢的清扫能力比蒸汽大的多，同时高压水的流速远小于蒸汽，动能的破坏作用比蒸汽小的多，因此大部分脱硝空预器配有高压水冲洗装置供在线或离线对空预器进行冲洗。豪顿华公司为空预器选择通洁公司的3D2A型高压冲洗水泵组,该泵组在现场集成安装，具有结构紧凑体积小的特点。主要参数如下表：

Because of the concentration of high pressure water jet, the shear strength is large and the cleaning ability of ash scale is much larger than that of steam. At the same time, the flow velocity of high pressure water is much smaller than that of steam, and the damage of kinetic energy is much smaller than that of steam. Houghton Hua company chose the 3D2A high pressure washing water pump group of Tong Jie company for the air preheater. The pump group is installed in the field and has the characteristics of compact structure and small volume. The main parameters are as follows:

空预器高压冲洗水系统就地布置如下图：

The layout of the high-pressure flushing water system for the air preheater is as follows:

2. 空预器差压增长趋势分析

Analysis of the growth trend of 2. air preheater differential pressure

2.1差压增长趋势分析

Analysis on the growth trend of 2.1 differential pressure

3号机组1月3日启动至今维持正常运行。机组启动后进行脱硝系统调试工作，3月底通过环保验收开始正常运行。从机组启动至今，两台机组空预器差压的变化趋势如下图：

Unit 3 started operation in January 3rd and has maintained normal operation. After commissioning of the unit, the commissioning of the denitration system is carried out, and the normal operation starts at the end of March through environmental protection acceptance. From the start of the unit, the variation trend of the differential pressure of the two sets of air preheater is as follows:

机组启动后满负荷工况空预器差压1月份到3月低维持在1.2-5kPa左右； 4月初随着脱硝正常投运、高负荷季节的到来，空预器差压增长速度加快；尤其是5月份，1号空预器差压从1.5kPa快速上涨至2.7kPa；2号空预器差压从1.5kPa快速上涨至2.1kPa。可以得出2个规律一是随着脱硝正常运行，空预器的差压增长速度加快，二是1号空预器差压的增长速度和峰值都比2号空预器高。

The differential pressure of the air preheater at full load condition after the unit started from January to March was low at about 1.2-5kPa. In the early April, with the normal operation of denitrification and the arrival of the high load season, the growth rate of the air preheater differential pressure increased rapidly; especially in May, the differential pressure of No. 1 air preheater increased from 1.5kPa to 2.7kPa, and the differential pressure of No. 2 air preheater increased rapidly from 1.5kPa. To 2.1kPa. It can be found that the 2 law is that with the normal operation of denitrification, the growth rate of the differential pressure of the air preheater is accelerated, and the two is that the growth rate and peak of the differential pressure of No. 1 air preheater are higher than that of the 2 air preheater.

2.2空预器堵灰加重后采取的措施

Measures taken after the 2.2 air preheater is aggravated

发现空预器差压快速增加后，主要采取了如下的措施：

After the rapid increase in differential pressure of air preheater, the following measures were taken:

1） 逐步缩短空预器蒸汽吹灰时间间隔，5月中旬两台空预器开始连续吹灰；

1) gradually shorten the time interval of steam soot blowing in air preheater, and two air preheater start blowing continuously in mid May.

2） 5月底将两台空预器吹灰阀后压力分别由1.0MPa提高至1.3MPa加强吹灰；

2) at the end of May, the pressure of the two air preheater blowdown valves increased from 1.0MPa to 1.3MPa to enhance soot blowing.

3） 适当降低脱硝控制效率，减少喷氨量；

3) appropriately reduce the control efficiency of denitration and reduce the amount of ammonia sprayed.

4） 积极准备空预器在线高压水冲洗系统的调研和调试工作。

4) actively prepare for the investigation and commissioning of the online high pressure water washing system for air preheater.

采取上述措施后，效果不明显，立即开始准备进行高压水冲洗工作。

After taking the above measures, the effect is not obvious, and immediately begin to prepare for high pressure water washing.

3.空预器在线高压水冲洗分析

Analysis of on-line high pressure water flushing of 3. air preheater

盘山发电公司在系统完成分步调试后，制定了严格的技术措施和操作注意事项经过精心准备，对3号机组2台空预器分别进行了两次在线高压水冲洗，效果较为明显，目前满负荷工况空预器差压降低到1.8kPa的可控范围内。

After completing the system step - by - step debugging, Panshan Power Generation Company has formulated strict technical measures and precautions for operation. It has two on-line high pressure water rinsing for 2 air predevices of unit 3, and the effect is more obvious. At present, the differential pressure of the air preheater at full load condition is lower to the controllable range of 1.8kPa.

3.1空预器冲洗效果分析

Analysis on the washing effect of 3.1 air preheater

3.1.1高压水冲洗过程根据系统要求，空预器在线高压水冲洗时选择单台空预器进行，2台空预器冲洗期间差压的变化趋势如下图：

According to the system requirements, the 3.1.1 high pressure water rinsing process selects a single air preheater when the air preheater is flushed with high pressure water. The change trend of the differential pressure during the 2 air preheater flushing is as follows:

3.1.2满负荷工况下冲洗效果

The flushing effect of 3.1.2 under full load condition

空预器在线高压水冲洗前后， 600MW满负荷工况下（总风量均在1420km3/h、总煤量均在250t/h左右）的空预器差压及风机电流对比如下：

Before and after the air preheater on-line high pressure water irrigation, the air preheater differential pressure and the fan current under the full load condition of 600MW (the total air volume is both 1420km3/h and the total coal amount are around 250t/h) are as follows:

从上表数据看出，经过在线高压水冲洗效果明显，具体效果如下：

According to the above table data, the effect of online high-pressure water washing is obvious, and the specific effects are as follows:

1）目前600MW负荷下（总煤量250t/h、总风量1420km3/h左右），31空预器烟气侧差压能维持在1.8kPa以

1) under the current 600MW load (total coal 250t/h, total air volume 1420km3/h), the differential pressure of the 31 air preheater flue gas side can be maintained at 1.8kPa.