As-fired coal quality online monitoring system and method for real-time operation control

Abstract

The invention relates to an as-fired coal quality online monitoring system and method for real-time operation control. The system comprises a coaling belt motor; a coaling belt driven by the coaling belt motor; delivered fuel coal; a sampler arranged on the coaling belt; a horizontal belt used for distributing coal bunkers; a horizontal belt motor driving the horizontal belt to operate; a plurality of coal ploughing devices mounted on the horizontal belt; a coal feeder; a coal feeder inlet bunker; a coal quality online detection device receiving a coal sample produced by the sampler and used for coal quality analysis; a material level change grading correction filtering module used for receiving signals of a material level sensor and correcting the material level; and a real-time as-firedcoal quality calculation device used for receiving signal data of all parts and outputting real-time quality of the as-fired coal. The invention further discloses the online monitoring method. The coal quality online detection device installed on the coaling belt at present can obtain as-fired coal quality online data meeting the requirement for real-time operation control, a low-cost solution isprovided for solving the common problem caused by coal quality fluctuations, and the practical value is remarkable.

Description

technical field [0001] The invention relates to the technical field of automatic control of thermal power plants, in particular to an online monitoring system and method for coal quality in furnaces used for real-time operation control. Background technique [0002] Under the condition of domestic electricity marketization, the operating environment of thermal power units is significantly different from that of foreign thermal power units. First of all, the designed coal type is affected by the reserves and the market-oriented operation of coal mines, which cannot guarantee the stable supply of power plants throughout the life cycle; secondly, under the condition of market-oriented coal prices but relatively fixed electricity prices, thermal power profits are greatly reduced, and low-quality coal is replaced Or mixed coal has become the inevitable choice of most power plants; third, the coal supply chain for electricity is long, and the huge economic interests drive various ...

AI Technical Summary

Problems solved by technology

On the one hand, this kind of coal quality detection device is relatively expensive. For the mainstream high-power coal-fired units with 5 to 6 coal mills, it is necessary to configure a coal mill for each coal mill to directly measure the coal quality online. On the other hand, the entrance and exit of coal mills designed in typical power plants do not reserve corresponding space and configuration schemes to install sampling and on-line testing equipment

Therefore, the existing practical online detection devices for coal quality in power stations are all installed on the coal loading belt, so that generally two units can share one device, and the investment cost is greatly reduced, but the direct problem is that the online detection is for the coal loading The quality of coal is not the quality of coal that is fired into the furnace in real time. There are a large number of links such as conveyor belts, coal plows, and raw material storage in the middle, which cannot be directly used for online actual operation control. It can only be used as a reference for operators within a certain range.

[0008] (2) There is a large uncertainty in estimating the quality of incoming coal by using online coal quality data

Under the premise that it is difficult to directly measure the coal quality of the furnace, it is theoretically feasible to estimate the coal quality of the furnace by using the coal quality of the upper coal and its related conveyor belts, coal plows, and material levels in the raw material bin, but there are great differences in practice. Certainty

After a lot of research and error analysis of practical applications, it is found that the accuracy required for direct real-time operation control mainly exists in the following aspects: a. The coal loading belt scale is limited by the structure, and it cannot be accurate for a long coal conveyor belt. Obtain the real-time coal quantity passing through the location in real time, which will cause a large error in determining the position of the sampling point corresponding to the coal quality detection result in the silo and estimating the time point of entering the furnace; b. The coal quality online detection device is often not configured An independent sampling device, but the sampling device originally designed for the coal handling system is used, but the conventional sampling device does not calibrate the sampling time when sampling and sampling is successful, so the coal sample produced cannot be reversed to obtain the original position of the sampling point , thus losing the key basis for the calibration of the position of the coal sample in the raw material bin; c. The measurement uncertainty of the raw material bin level is large

On the one hand, the measurement of the material level of the raw material silo itself is relatively difficult, and the output of the material level measurement device based on point measurement often has great uncertainty due to the collapse of the top section of the material level in the silo, the height of the stack, and vibration. In this way, it is difficult to accurately obtain the position of the detected coal sample, and the large cross-section of the silo makes the measurement time accuracy of the actual coal quality change in the furnace deviate by several minutes, exceeding the accuracy requirements required for real-time operation control

[0009] To sum up, although various types of coal quality on-line detection devices have emerged, it is still impossible to obtain the coal quality detection data required for real-time operation control due to various factors. Coal power plant operators have become a key problem to be solved urgently

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