Table of Content

20 February 2019, Volume 55 Issue 1

Previous Issue    Next Issue

Development and Commentary

Engineering Discuccion of Earthing and Bonding for Instruments and Control System

2019, 55(1):  0-0. 

Asbtract ( )  

Related Articles | Metrics

Abstract：The three actions of protect earthing and the three actions of common bonding for instruments and control system earthing purpose are introduced in the article. As earthing functions, earthing types can consist of protect earthing, instrument common earthing, shield earthing, intrinsical earthing, electrostatic protective earthing, lightning protective earthing, etc. According to basic concept, working principle and electrical property, earthing schemes such as star bonding，net bonding and star-net mix bonding are introduced and benefit of net bonding. According to principle of safety power utilization, it is recommend that equipotential bonding and electricity common earthing system. Engineering methods and bonding types of earthing are discucced. Anti electrical disturb effects and earthing philosophy and notes are discucced that often used methods for engineering design and implement.

Engineering Design and Standards

The Method of Thermowell Strength Calculation

2019, 55(1):  0-0. 

Asbtract ( )  

Related Articles | Metrics

Aiming at the temperature detection elements with thermowell in the project, this article expatiates an effective method used for accomplishing the thermowell strength calculation and qualification criterions according to the ASME code and other literature and datum, describes the range that it can be used, summarizes four qualification criterions for the thermowell strength calculation, they are frequency limiting condition, steady-state stresses limiting condition, dynamic stresses limiting condition and pressure limiting condition. We also describe the detail steps to validate the qualification criterions.

Discussion on Type Selection for on-line LEL analyzer in Regenerative Thermal Oxidizer Plant

2019, 55(1):  0-0. 

Asbtract ( )  

Related Articles | Metrics

Volatile organic compounds (VOCs) exhaust from coal-to-chemicals plants usually shall be disposed by regenerative thermal oxidizer (RTO) plant. On-line LEL analyzer is the critical instrument in RTO plant, which is associated with the plant’s safety. The RTO process and calculation methods for lower explosion limit (LEL) of mixing combustion gas are briefly introduced. According to the components of off-gases from rectisol plant in one coal-to-chemicals project, the measure principle and main advantage and disadvantage of four kinds of LEL analyzers are emphatically introduced, which are flame temperature (FTA) analyzer, catalytic combustion (CAT) gas detector, flame ionization detector (FID) process gas chromatography and infrared (IR) analyzer. The lag time of sample gas transport is estimated. As to the off-gases from rectisol plant, The recommendations of type selection for on-line LEL analyzer are provided.

The Cross-sectional Selection Method of Instrument Power Cable

2019, 55(1):  0-0. 

Asbtract ( )  

Related Articles | Metrics

According to the application of power cable for instrument in chemical plant, combined with the common laying mode of cable, the cross-sectional calculation of the core is based on the current carrying capacity of the cable, then the calculation method of the voltage drop is given to check whether the result can meet the requirements. Finally, based on the Visual C# development environment, the cross-sectional calculation software is implemented. The application results show that the method is accurate and effective, and improves the quality and precision of engineering design.

The scheme and application based on the self-controllable long-distance pipeline station control system

2019, 55(1):  0-0. 

Asbtract ( )  

Related Articles | Metrics

This paper mainly analyzes the current long-distance pipeline technological requirements of remote monitoring station control system and the difficulty of monitoring, this paper introduces the features of the domestic PLC product as an example, and the situation and gap between the domestic and foreign products, based on these points and features, detailed elaborated the independent control PLC products applied in the long-distance pipeline station on the concreteness scheme of control system, respectively for clock synchronization scheme, remote maintenance plan, the entire network diagnoses, the whole system antivirus solutions, single station network, through the success applied in Tianjin LNG pipeline, prove the feasibility of this scheme.

Process and Technology

Differential Evolution Neural Network Disturbance Observer Design

Sun Ming

2019, 55(1):  0-0. 

Asbtract ( )  

Related Articles | Metrics

Due to the fact that the conventional nonlinear disturbance observer has large errors of equivalent interference estimation and is easily affected by parameter perturbation, a neural network disturbance observer is designed based on the differential evolution algorithm. First, the neural network is used to approximate the unknown integrated disturbance, and a state-dynamic equation is designed to test the effect of disturbance observer estimation. Secondly, the differential evolution algorithm is introduced to adjust the neural network weights online so that the approximation errors are ultimately uniformly bounded. Finally, in MATLAB, this method is used to estimate the external disturbances of a class of nonlinear uncertain systems—inverted pendulums. The simulation results show that the proposed method can effectively improve the estimation accuracy of the observers, and has a better robustness on the parameter fluctuation of the controlled object.

Optimization of Wavelet Analysis in Pipeline Leakage Signals Denoising

2019, 55(1):  0-0. 

Asbtract ( )  

Related Articles | Metrics

In order to solve the real-time discovery, precise positioning and accident disposal of oil and gas pipeline leakage, the optimization method of wavelet analysis in denoising of pipeline leakage signal is studied. Through the theoretical comparison analysis of Fourier transform and wavelet transform, a more superior wavelet denoising method is selected. A simulation comparison of the signal processing results is performed under the soft and hard threshold methods by using MATLAB software. On the premise of combining the general principles of wavelet base selection, five common wavelet functions are studied, the mathematical characteristics and the trend of the corresponding wavelet function graph are analyzed. Based on the index of signal-to-noise ratio and root-mean-square error, a signal denoising method combining double contrast and three-step optimization is proposed analyzing the denoising effects of different denoising methods and decomposition scales.

Research on Improvement of Target Tracking Algorithm Based on Camshift

2019, 55(1):  0-0. 

Asbtract ( )  

Related Articles | Metrics

The Camshift target tracking algorithm is a target tracking algorithm based on the color feature information. In the process of tracking the target, the Camshift algorithm calculates the reverse projection of each frame according to the color feature histogram of the target, and takes the position and size of the target tracking target as the location and size of the initialization of the target search window of the front frame. Small. In order to track the moving targets effectively, an improved Camshift algorithm based on Kalman filtering and particle filtering algorithm is proposed in this paper. First, this paper uses the improved Camshift algorithm based on Kalman filtering to achieve target tracking . Secondly, in order to improve the stability and effectiveness of tracking, the particle filter algorithm is introduced to correct the target center position of the Camshift, and the robustness of the target tracking is proposed without affecting the real-time tracking. The experimental results show that this method can still achieve target tracking effectively when the image background is complex and the target is blocked for a long time.

Realization of automatic combustion and load coordination control for three furnace two unit circulating fluidized bed unit

2019, 55(1):  0-0. 

Asbtract ( )  

Related Articles | Metrics

The current situation and problems of the existing control system of CFB boiler are analyzed. The optimization of combustion optimization and multi furnace load coordination control system of CFB boiler is analyzed and investigated. The implementation scheme of automatic optimization of combustion of CFB boiler units and the realization of coordinated control of multi furnace load are determined to achieve the goal of saving energy and reducing consumption, reducing the intensity of labor and realizing the efficiency of the device.

Application of advanced process controller of ethylene cracking depth in Qilu Petrochemical Company

2019, 55(1):  0-0. 

Asbtract ( )  

Related Articles | Metrics

The establishment of the cracking depth predictive model using neural network technology, the development and implementation of advanced process controller of the cracking depth of Qilu Petrochemical Company 10 sets of liquid cracking furnace based on Smith predictor technology, overcomes the impact of oil property fluctuation, stabilize the cracking depth, improve the yield of double ene.

Safety and Environment Protection

Research and Application of Safety Integrity Level Evaluation Method Based on Layer of Protection Analysis

2019, 55(1):  0-0. 

Asbtract ( )  

Related Articles | Metrics

Safety Instrumented System (SIS) is a device widely used in petrochemical enterprise. Safety Instrumented Function (SIF) executed by Safety Instrumented System is the last line of defense of petrochemical enterprise protection system. There are many problems such as wrong interlocking loop and irrational detection cycle with SIS in petrochemical enterprise in China at present, therefore, People's Republic of China emergency management department (called State Administration of work safety before) released Guidance of the State Administration of safety supervision on strengthening the management of chemical safety instrumented systems in 2014, which focus on strengthening the management of chemical safety instrumented systems and reducing the happening of the dangerous chemical accidents. According to IEC61508 and IEC61511 released by International Electrotechnical Commission (IEC), Security Integrity Level (SIL) of a interlocking loop of reaction feeding system in a coal to liquid and chemical corporation was graded using Layer of Protection Analysis (LOPA), and the interlocking loop was verified by using exSILentia afterwards. At last, rationalization proposals for interlocking loop which dissatisfied secure request were proposed to guide enterprise conducting self-censorship for their stark fault line within the safety process.

Application of PLC System Based on Fieldbus in Sewage Treatment Plant

2019, 55(1):  0-0. 

Asbtract ( )  

Related Articles | Metrics

Fieldbus control technology has digital and intelligent technical characteristics. In order to apply this technology to coal chemical industry wastewater treatment plant and give full play to its efficient technical advantages, a PLC control system based on fieldbus technology was used in a pilot project of wastewater treatment process implemented by a coal chemical industry project team.This paper mainly introduces the hardware and software system of the PLC control system and the main monitoring scheme of the pilot plant, summarizes the experience of the system in installation, debugging and operation and analyzes the reliability and advancement of the application of fieldbus control technology in sewage treatment plants.

Intelligentization and Information Technology

Promoting Big Data to Information, On the Way to Smart Refinery

2019, 55(1):  0-0. 

Asbtract ( )  

Related Articles | Metrics

Most modern refineries use a large number of intelligent instrument equipment, equipped with advanced PCS (Process Control System), MES (Manufacturing Execution Systems), ERP (Enterprise Resources Planning), process control, production management, enterprise management, the three layers are connected and integrated, the basic realization of the refinery digitization. However, the current digital refinery not only meets the bottleneck of the improvement of operation efficiency and production benefit, but also basically stays at the conceptual level for the industrial 4 tide of smart factory. Fortunately, modern refineries have massive process data and management data (called "big data"), and big data is the bridge for upgrading digital refinery to smart refinery. Based on the existing digital platform(including software and hardware), we can enrich and select the useful data of refining process, optimize and promote product management data ,upgrade the big data to decision-making information , then build the intelligent integrated control system which is driven by ERP as the engine. It is the realization of big data information, the key step to information refinery, the only way to smart refinery. Since 2014, Huizhou refinery has upgraded the digital information platform by optimizing the intelligent instrument diagnosis software, adding wireless expert diagnosis systems and wireless PAD inspection, and strengthening the prediction management, driving management and systematized information management, and so on. By 2017, the Huizhou digital refinery has been successfully transformed to intelligent information refinery, also played an exemplary role in the construction of smart refinery in Chinese petrochemical industry.

The key technical framework of oil and gas pipeline integrity management in information system

2019, 55(1):  0-0. 

Asbtract ( )  

Related Articles | Metrics

Abstract:A set of information system based on oil and gas pipeline integrity management, is to carry out the state of the effective measures to strengthen oil and gas pipeline risk management requirements, is the urgent need to enhance the level of pipeline management. This paper briefly introduces the key technical framework of the pipeline information system in combination with the construction content of the pipeline integrity management information system of our company, sinopec intelligent pipeline management system.

Innovation and Practice

Introduction of Instrument Control Strategy of Parallel Slide Valve Retrofit Program in the top of Coke Drum

2019, 55(1):  0-0. 

Asbtract ( )  

Related Articles | Metrics

Weighing Data Acquisition System Base on RS-232/485

2019, 55(1):  0-0. 

Asbtract ( )  

Related Articles | Metrics

This article introduces a kind of check weighing data acquisition system base on RS-232/485.Check weighing data is transmitted to a data acquisition computer in central control room,finally it is transmitted to a database server after identificated and processed by a application program.The database server also offers Web Service.Users in LAN can check,count,analysis and manage check weighing data via web browser access to Web Service.All of this make it possible for central control room to control packaging quality real-time.

22/5000 Introduction to the electric vortex sensor instrument measures the elimination of signal interference in the system

2019, 55(1):  0-0. 

Asbtract ( )  

Related Articles | Metrics