AI-embedded Dynamic Dense Medium Controlling in Coal Washing Plant

Location: Jiangzhuang Coal Mine Coal Preparation Plant

Date: 2022-09

Project Content: This is the construction project of the density control system of Jiangzhuang Coal Preparation Plant. The goal of this project is to achieve the intellectualization of the density control system of the coal preparation plant.

Project Introduction:

Jiangzhuang Coal Mine CHPP upgraded and constructed two sets of dense medium systems with a three-product DSM cyclone in 2014. The original system relies on manual operation to adjust the water replenishment of the dense medium, such as water replenishment for the split-flow box and mixing barrel, during the control process.

By applying the intelligent density control system of HOT, the plant has achieved:

1) Automation of density adjustment;

2) Automation of split-flow operations;

3) Automation of dense medium and water replenishment;

4) Intelligent density parameter setting;

5) Intelligent parameters for split-flow;

6) Intelligent parameters for dense medium and water replenishment.

While implementing the above functions, the interface is reserved, which the centralized remote operation (non-intelligent) and local operation can be selected in the system.

System Composition:

The system is mainly composed of intelligent servers, centralized control room operation stations, networks, PLC control cabinets, on-site control cabinets, on-site operation units, on-site instruments, sampling devices, transfer belts, etc.

The physical control layer of the entire automation control system is divided into four layers:

1. Intelligent decision-making layer

Consisting of servers, databases, intelligent decision-making applications, and a preset expert database, the system has the function of autonomous learning and decision-making.

2. Central monitoring layer:

It is located in the central control room and realizes the display and control of on-site data and equipment operation status through industrial control computers and industrial Ethernet.

3. On-site PLC control station:

Established two sets of PLC control stations to complete on-site data collection, logical control, and information recording functions within the monitoring range, and achieve automatic control (linkage and interlocking control) of equipment within each monitoring range;

4. On-site instrument and actuators layer:

It's distributed on the process site and the specific physical information collection functions are completed by instruments such as flow, concentration, and density monitoring. Actuators such as valves and split-flow boxes to execute control commands, ensuring that the density, coal quality, and so on can meet the target requirements.

The Openness and Scalability of The System

The entire intelligent system adopts an open network structure, forming a hierarchical system information layer. The central control computer exchanges data with the on-site PLC substation through relevant communication equipment, and receives control commands issued by the intelligent control center and dispatchers. The on-site PLC control station is composed of a PLC controller with logic control functions and a local measurement and control instrument unit. It mainly completes the collection of on-site process data and the control of automation instrument equipment, while transmitting the collected data to the main station and reporting the operation status.

System Advantages

1. After the transformation of dynamic dense medium control system, the original manual open loop control of the dense control can be upgraded to automatic closed loop control of the dense control to stabilize the separation density. By collecting the ash content data of clean coal and raw coal, and using fuzzy algorithms to study and analyze the quality of clean coal products, it can reduce the fluctuation of product ash content and improve the yield of clean coal; At the same time, the system needs to retain the original manual automatic remote-control function, which can achieve basic functions such as remote adjustment of diversion, water replenishment, and liquid level in preparation for emergency production needs.

2. The intelligent system realizes intelligent setting and control of suspension separation density in continuous production process. HOT provides customized services to the owners based on data indicators fed back by clean coal ash content, raw coal ash content, and other artificial intelligence algorithms such as quality control algorithms.

3. An intelligent dense medium density control system under the C/S architecture has been formed to achieve intelligent back control and adjustment of density setting values based on coal quality and indicators, with a suspension density fluctuation range of ≤ ± 0.005g/cm3,

4. Real-time display, monitoring, and adjustment of process parameters such as feed pressure, suspension density, magnetic content of suspension, slime content, and liquid level in the mixing drum of the dense media separation system, with timely and automatic replenishment for water, dense medium, and other department.

5. The system can control and adjust the set value of sorting density. Product ash control accuracy: ± 0.3%; The density value of the suspension can be detected in real time, and the density value can be adjusted in real time through artificial intelligence methods such as fuzzy control algorithms, with a density control accuracy of ± 0.003g/cm3.

The intelligent control system has a built-in expert database and has the ability of self-learning. Experts can preset rules to collect on-site data and issue instructions for density setting, media replenishment, and water replenishment to ensure that the coal quality reaches the required area; The control system can monitor the operation status of all on-site equipment and follow the instructions of the intelligent system and dispatcher to control the equipment; The control system has built-in PID, robust control, and other algorithms to keep the density of the medium within the range that meets the sorting requirements. The control system transmits the collected key data such as ash content, density, and concentration to the intelligent density control system in real time, accumulating data for the density control system.