1. Plant Profile

Zhejiang Zheneng Yueqing Power Co., Ltd. is an affiliate of Zhejiang Energy Group Co., Ltd., located in Yueqing City, Wenzhou. It has a total installed capacity of 4.665 million kilowatts. The Phase I and Phase II projects are each equipped with two 660MW units, while the Phase III comprises two 1000MW ultra-supercritical units. Its technical and economic indicators rank among the top peers of the same type.

2. Project Overview

Large-scale integration of new energy power and inter-provincial power transmission have resulted in a large peak-valley load difference for the units, raising higher requirements for operational flexibility. To cut the consumption of high-calorific coal, the coal blending mode needs dynamic adjustment in line with load schedules: more bunkers for high-calorific coal are put into service at high load to guarantee peak power supply capacity, while fewer are used at low load. The system is required to satisfy both deep peak regulation and peak load operation demands simultaneously.

Due to the large volume of raw coal bunkers, coal type replacement lags behind with low accuracy after coal blending adjustment. This leads to problems such as failure to burn high-calorific coal during peak loads and low-calorific coal during low loads. Rapid switching between high and low operating loads cannot be realized, undermining unit flexibility. In addition, frequent coal blockages occur in raw coal bunkers, calling for the installation of rotary scraper anti-blocking devices.

To address the above challenges, DaTongLongYuan undertook the upgrading and renovation of the intelligent coal blending system for No.3 Boiler. The project adopts a coal blending process combining interconnected coal feeders and intelligent logic regulation, together with supporting rotary scraper anti-blocking and cleaning devices for raw coal bunkers. After full-cycle work including scheme optimization, equipment installation, system joint commissioning and operating condition testing, on-site debugging has been successfully completed. The system is now ready for stable operation, marking the full digital and intelligent upgrade of coal blending modes at Zheneng Yueqing Power Plant.

3. Renovation Results

As a key upgrade project for energy conservation, efficiency improvement and green transformation in the power industry, the adopted coal blending process realizes precise blending and transportation of different coal types via equipment linkage and automatic programs, which can adapt dynamically to real-time operating conditions of the units.

Targeting common industry problems — bunker distortion and even detachment risks caused by unbalanced material levels and loads on both sides of partitioned bunkers, as well as coal spontaneous combustion and caking resulting from coal accumulation outside shrimp-bend bunkers — customized optimizations have been carried out in three aspects: equipment structure, operational procedures and control strategies. These improvements completely eliminate recurring faults and resolve the drawbacks of traditional partitioned bunkers, including frequent coal blockages and uneven coal blending.

Furthermore, the renovation involves no modifications to the FSSS main protection system and original control logic. The unit’s AGC system and air-coal ratio adjustment functions operate normally. Complete and accurate data on fuel consumption statistics and unit economic analysis fully ensure the stability and reliability of the original operation system.

4. Future Outlook

This project represents another major achievement of in-depth cooperation between DaTongLongYuan and Zhejiang Energy Group, as well as another successful application of intelligent coal blending technology on mainstream thermal power units.

Going forward, DaTongLongYuan will continue to focus on thermal power intelligence, energy conservation and carbon reduction. The company will keep iterating and optimizing core technologies for intelligent coal blending and deep peak regulation. Leveraging rich project experience, we will deliver customized and integrated digital and intelligent solutions for more power enterprises. We strive to help the traditional thermal power industry improve quality and efficiency, accelerate green and low-carbon transition, and contribute to the development of a new-type power system.