Atmospheric Oil Partition Process - Drawings

Contents

Introduction

Question analysis and task setting

Unit composition and description of main process units

Examples of automation in the oil and gas industry

APCS UPVSN of Aktash Commodity Park

ACS of gas-air duct of steam boiler

Review findings and statement of work

Development of I&C functional diagram

2.1 Description of the automation object

2.2 Automated Functions

2.2.1 Control functions

2.2.2 Unit emergency protection

2.2.3 Process Indication

2.3 Selection of measuring instruments and actuators

3. Development of I&C structural diagram

3.1 Main Features

3.2 Lower level of control system

3.3 Upper level

4. Development of electrical schematic diagram

5. Developing a Connection and Connection Diagram

6. Design part

6.1 Investigation and adjustment of the control loop

6.1.1 Functional diagram of control loop

6.1.2 Description of elements by transfer functions

6.1.3 Structural diagram of control loop

6.1.4 Control Loop Study

6.1.5 Conclusions from the results of the study

7. Software and Math

7.1 Development of control algorithms

7.2 STEP7Lite Software

7.3 Graphical Operator Interface

7.3.1 Overview of existing SCADA systems

7.3.2 Analysis and selection of operator interface development environment

7.3.3 Operator GUI Description

8. Calculation of the economic effect from the introduction of ACS by the process of atmospheric distillation of oil

8.1 Design Design Costs

8.1.1 Calculation of the number of developers

8.1.2 Calculation of salary of developers

8.2 I&C Equipment Complex Costs

8.3 PID erection and commissioning costs

8.4 ACS Software Costs

8.5 Staff Training Costs

8.6 I&C Maintenance Costs

8.7 Calculation of ACS implementation results

8.8 Calculation of economic effect

9. Safety of life

9.1 Analysis of hazardous and harmful production factors at the workplace of the operator of ACS of atmospheric distillation of oil

9.1.1 Unfavorable microclimate parameters

9.1.2 Insufficient illumination of the working area

9.1.3 Increased level of electromagnetic radiation

9.1.4 Danger of electric shock

9.2 Measures to reduce and eliminate hazardous and harmful factors

9.3 Calculation of Labour Process Tension

9.3.1 Intellectual Loads

9.3.2 Sensor loads

9.3.3 Emotional Loads

9.3.4 Monotonicity of loads

9.3.5 Operation mode

9.4 Determination of room category by fire and explosion safety

Conclusion

Bibliographic list

Appendix A Terms of Reference

Appendix B Patent Search Reference

Appendix C List of elements for electrical schematic diagram

Appendix D List of elements for connection diagram

Summary

In the diploma project, an automated control system for the process of atmospheric distillation of oil is being developed.

Currently, systems of this level are widespread in the petrochemical and oil refining industries.

This APCS monitors, visualizes, controls the process and performs emergency protection functions. The management system uses Simatic hardware and software from Siemens.

The diploma draft contains an explanatory note and a graphic part.

The graphic part of the project consists of nine sheets: functional diagram of automation of the control object (1 sheet of A1 format), block diagram (1 sheet of A1 format), schematic diagram (1 sheet of A1 format), connection and connection diagram (2 sheets of A1 format), control algorithm diagram (1 sheet of A1 format), adjustment of control system (1 sheet of A1 format), software and mathematics (1 sheet of A1 format), graphical operator interface (1 sheet of A1 format).

Explanatory note is 129 pages, 33 figures, 14 tables, 24 bibliographic sources, 4 annexes

Terms of Reference

1 Name and scope

Automated system for controlling the process of atmospheric distillation of oil. The field of application is the installation of AVT in Novoshakhtinsky refinery OJSC.

2 Purpose and purpose of development

The purpose of this development is to create a new automated system for controlling the process of atmospheric distillation of oil.

3 Sources for development

Sources for development are:

- process diagram of atmospheric distillation process;

- process description.

4. Technical requirements

4.1 Product Composition and Structural Design Requirements

The control system consists of:

- control unit based on programmable controller;

- automated workstation of AWS;

- software supplied with CDROM.

4.2 Assignment Indicators

Atmospheric distillation APCS shall provide:

- process maintenance based on automatic control of process parameters;

- reduction of labour intensity during measurement and control of technological operations;

- visualization and timing of process parameters and emergency events;

- archiving of data allowing to evaluate the quality of process parameters control in order to make recommendations for improvement of plant operation;

- automatic actuation of standby equipment in case of malfunction of the main equipment (pumps, etc.);

- automatic control of actuators;

- emergency-free start-up/shutdown and switching of process equipment;

- preventing the development of emergency situations and ensuring the safe completion of the process according to a given program;

- reception of information from the upper level of automation system and generation of control actions on actuators;

- operation of process control programs in accordance with logic of control algorithms;

- calculation and analysis of design parameters indirectly characterizing the process.

4.3 Reliability Requirements

Reliability indicators of the System shall meet the requirements of GOST 24.70186 ESS ACS "Automated Process Control Systems. Reliability. Basic provisions "and item 6.3.10 of PB0954003.

The functional subsystem software shall prevent failures in the performance of APCS functions in case of failures of functional subsystem hardware and in case of human errors involved in the performance of this function, or shall ensure the conversion of failures leading to large losses to failures involving less losses.

The system shall be multifunctional, recoverable and shall meet the following reliability requirements:

- readiness factor, must be not less than 0.995;

- mean time between failures of the system computer equipment complex must be at least 30000 hours.

The following processor modules must be duplicated in the system; power supplies; communication lines.

In addition to the hardware reserve, the system must have temporary and functional redundancy (the degree of controller load, the reserve of memory capacity and free functional units, etc.).

4.4 Requirements for processability and metrological support of development, production and operation

The system must meet the requirements of openness (i.e. should use standard international input and output signals, interfaces and structures), which will allow, if necessary, to connect new modules and units without violating the overall configuration of the system and significant costs.

Metrological support of APCS shall meet the requirements of:

- GOST 24.10485 ESS ACS "Automated control systems. General requirements ";

- MI 166987 ESS ACS "Metrological support of ACS. Basic Provisions ";

- PB 0954003 "General Explosion Safety Rules for Explosion and Fire Hazardous Chemical, Petrochemical and Oil Refineries" (Section 5.6), as well as the requirements of the standards of the State System for Ensuring Uniformity of Measurements (GSI), Unified Standard System for Automated Control Systems (ESS ACS).

4.5 Requirements to the level of unification and standardization

The developed system should be universal, provide the possibility of its use on a wide class of control objects.

When developing the control system, it is necessary to ensure maximum unification of the used units and parts; Use of standard fasteners.

Use of mass-produced components is at least 95%.

All purchased items and components included in the package shall be of general purpose and shall not be subject to approval.

4.6 Safety and Environmental Impact Requirements

APCS hardware shall comply with the following requirements:

- PB 0956303 "Industrial Safety Rules for Oil Refineries." PB 0357603 "Rules for design and safe operation of pressure vessels";

- PB0954003 "General explosion safety rules for explosion and fire hazardous, chemical, petrochemical and oil refining industries";

- PUE2002 ch. 7.3 "Electrical Installation Regulations";

- GOST 12.2.07081 "Safety Rules for Electrical Circuits";

- PBE NP2001 "Rules for safe operation and labor protection for oil refineries."

- SanPiN 2.2.2/2.4.134003. "Hygienic requirements for personal electronic computing machines and organization of work."

- GOST 2586183 "Computers and data processing systems. Electrical and mechanical safety requirements and test methods. "

All external components of the system equipment under voltage shall be protected against accidental human contact, and the equipment itself shall be grounded in accordance with the requirements of GOST 12.1.0302001 SSBT "Protective grounding, grounding" and "Electrical Installation Rules" PUE2002, Chapter 7.3.

Installation of technical facilities shall comply with the requirements of the current "Rules for technical operation of electrical installations of consumers" (PTE 2003).

Safety requirements during installation, adjustment, operation, maintenance and repair of APCS hardware shall be specified in the documentation for hardware.

4.7 Aesthetic and ergonomic requirements

Serviceability shall be provided as per GOST 12.2.049.80. Occupational safety standards system. Production equipment. General ergonomic requirements.

Provide aesthetics according to GOST 20.39.10885. Comprehensive system of general technical requirements. Requirements for ergonomics, habitability and technical aesthetics. Item and selection order.

The general ergonomic requirements for the operator room and the location of workplaces must comply with GOST 2195876 "General ergonomic requirements for the location of workplaces."

General ergonomic requirements governing the organization of the workplace, mutual location of communication means within one workplace - according to GOST 2226976 "System Man - Machine. Operator's workplace. Relative location of work center elements. General ergonomic requirements. "

4.8 Requirements for product components, raw materials, initial and operational materials

Components of both domestic and imported production can be used in the development.

4.9 Operating conditions. Maintenance and repair requirements

APCS shall be designed for continuous round-the-clock operation.

Types, periodicity and maintenance schedule of equipment shall be specified in the corresponding operating instructions.

The Supplier shall provide the Customer with a list of units, components, connectors and units subject to preventive inspection, calibration and verification, indicating the periodicity of the latter, as well as instructions for the performance of these works.

For normal operation of computer and microprocessor equipment in the rooms of hardware and control rooms the following conditions shall be provided:

- ambient temperature: (22...24) OS;

- relative humidity of ambient air: (40... 60)% without condensation;

- dust content of air in the room (control room and equipment room) - not more than 0.3 mg/m3 with particle size not more than 3 μm;

- vibration frequency must be not more than 14 Hz at displacement amplitude not more than 0.5 mm;

The location of APCS equipment shall be rational both in terms of installation links between them and the convenience and safety of their operation and maintenance.

4.10 Requirements for Transportation and Storage

Storage of system units shall be performed in packagings in a closed room at temperature from + 5 ° С to + 35 ° С and relative humidity not more than 85%.

Component parts of BC shall be transported in the manufacturer's package in closed transport (road, railway, air in heated compartments) under storage conditions 5 as per GOST 1515080.

Introduction

Automation of various types of production is an important area of ​ ​ scientific and technological development of society. Automation leads to an increase in labor productivity, the removal of a person from the production process, to an improvement in the quality of the process and to a more complete satisfaction of the needs of society.

The relevance of the topic of the diploma project is explained by the requirements for ensuring the safety of technological processes in explosion and fire hazardous objects, which include the process of atmospheric distillation of oil. The safety task can be solved only with the help of an automated system of control, control and protection of technological production using highly reliable modern automation tools.

ACS with the process of atmospheric distillation of oil will increase the volume of primary distillation of oil, ensure the improvement of oil refining technology, the introduction of new technological processes, effective catalysts, and progressive equipment. The introduction of automation will reduce scrap and waste production, reduce costs for raw materials and energy, reduce the number of main workers, and ensure deep oil refining.

The purpose of this diploma project is to develop an automated system for controlling the process of atmospheric distillation of oil. The basis of the developed control system is the Siemens Simatic set of hardware and software controls. Simatic components meet the highest modern requirements for performance, reliability, security and manageability.

Question analysis and task setting

1.1. Unit composition and description of main process units

The plant is designed for oil fractionation, in order to obtain light oil products. Plant composition:

stripping column

sprinkling tank

4 refrigerator air condensers

heat exchanger

5 pumps

Consider the process of atmospheric distillation of oil:

Oil flows of heated demineralized and dewatered oil are supplied to rectification column. Here, the rectification process is a heat - and - mass exchange process of separating liquids that differ in boiling temperature due to countercurrent, repeated contact of vapors and liquid. In the column, 2 streams pass through each tray countercurrent:

liquid - reflux flowing from the underlying plate;

vapors coming from the underlying to the overlying plate;

The vapors and liquid entering the dish are not in equilibrium, however, entering equilibrium tends to this. The liquid stream from the overlying tray enters the higher temperature zone, and therefore some low boiling component evaporates therefrom, thereby reducing the concentration of the latter in the liquid. On the other hand, the vapor stream coming from the underlying tray into the lower temperature zone is condensed and a portion of the high boiling product from this stream is transferred to the liquid. The concentration of the component in the vapors is thus reduced and the low boiling point is increased. The fractional composition of vapors and liquid continuously varies in the height of the column. The portion of the distillation column that is located above the feed inlet is called the concentration column and the portion below the inlet is called the stripping column. In both parts of the column, the same rectification process takes place.

From the top of the concentration part in the vapor phase, the desired product of purity is removed - rectificate, and from the bottom plate - liquid, still sufficiently enriched with a low-boiling component. In the stripping part, low-boiling fractions are stripped from this liquid, and high-boiling product, bottom residue, is removed from the lower part of the column.

Thus, from the top of the column, a mixture of hydrocarbon gases, gasoline vapors and water vapor is withdrawn to the air condensers of the KVK1XVK4 refrigerators. Here, vapor condensation occurs due to air cooling to 35 ° C. Then condensate enters the reflux tank. Here the condensate is settled and divided into gasoline and water. Water is discharged from the tank and withdrawn from the unit.

Gasoline is supplied from the reflux tank to the reception of H3/1H3/2 pumps. Part of the gasoline from the tank is supplied by the same pumps to the top of the column as acute reflux. The other part of the gasoline with the balance temperature, through the valve, is withdrawn from the plant as a finished product.

Hydrocarbon gas from the top of the tank is sent to the fuel gas separator. Corrosion inhibitor solutions of "Hercules 1017" type in the amount of 10 g/t of oil and neutralizer are supplied to the pipeline at the outlet of the column to prevent hydrochloric and hydrogen sulfide corrosion of the equipment.

To prevent the pressure increase in the column and the tank above the maximum permissible one, manual control valves are installed on them to open the discharge to the flare header.

Stripped oil from the bottom of the column by pumps H2/1H2/2, after preheating in a heat exchanger, where it is mixed with oil from a distillation column to obtain a product with a higher boiling point, is sent for further processing.

The possibility of emergency pumping of excess oil from the column by pumps H2/1H2/2 back to the feed tank farm is provided.

1.3. Review findings and statement of work

The examples of ACS discussed allow us to say that modern management systems are decentralized, giving: flexibility; high performance due to separation of functions between control devices; The ability to increase resources significantly over centralized management systems. A significant advance of industrial Ethernet in the field of ACS can be noted, due to the huge choice of compatible hardware and software for building networks of this standard. Existing system solutions guarantee the demand of industrial Ethernet in the future. First of all, it is a combination of industrial computers, workstations and terminals used as operator workplaces.

During the degree design, a patent search was carried out, as a result of which a review of all types of rectification columns was carried out, patents and copyright certificates for these developments were selected, which are different in their technical solutions and are the most promising (Patent Search Certificate, Annex B). The most promising work in this area has occurred in the last decade in connection with the development of modern technology. The plant uses the most suitable stripping column for the process.

The basis for the development of ACS by the process of atmospheric distillation of oil is the need to automate the installation of atmospheric distillation of oil with an increase in the capacity of the plant to 2.5 million tons per year for raw materials at Novoshakhtinsky ZNP OJSC

The use of ACS will automate the process, increase the level of productivity, increase the quality of products, prevent emergencies, and reduce the psychological burden on the operator. In this regard, the terms of reference for the design were developed.

Development of functional diagram of asu tp

2.1 Description of the automation object

The function chart of automation is submitted on sheet DP2068998A12500.00.000.A2 of a graphic part of the project and in figure 2.1. Recommendations [8] were used in the development.

The functional automation diagram (diagram A2) shows the elements of the atmospheric oil distillation unit: a stripping column, 4 air condensers of the HVK refrigerator, an reflux tank, a heat exchanger, 5 pumps. The pipelines connecting these elements to each other with the various elements of this unit and other units of the refinery are shown. All pipelines have a direction, the name of the transported substance is indicated and the diameter of the pipeline is indicated. The process is described above. The following are the justifications of controlled, signaled, regulated parameters and channels for introducing control actions, as well as the substantiation of the selection of measures for protection and blocking.

2.2 Automated Functions

Emergency protection of the unit.

In order to determine the criteria for the occurrence of emergency situations and to select the option of their elimination, it is necessary to collect information on critical parameters of the process and equipment:

Pumps N1, N-2/1, N2/2, N-3/1, N3/2.

The bay of pumps is monitored by sensors 61, 7-1, 81, 9-1, 101 with alarm and output of interlock by minimum value. Temperature of pumps bearings is controlled by sensors 411, 42-1, 431, 44-1, 451 with alarm and output of interlock signal by maximum value (90 ° С).

When gasoline in the tank reaches the minimum value (500 mm), pumps N3/1, N-3/2 are stopped by sensor 251. The interlocking signal is also output by the device 271, the pumps N3/1, N-3/2 are stopped and the shut-off valve RN4 is closed.

Level in the column is monitored by sensor 261, with alarm by maximum and minimum values and output of interlocking signal when the maximum minimum value is reached, shutdown of pumps N2/1, N-2/2,

2.3 Indication of process of atmospheric distillation of oil.

For this purpose, we use the sensors discussed earlier, and also monitor additional process parameters and equipment condition:

- temperature monitoring: at heat exchanger inlet and outlet by sensors 11, 2-1, 31, 4-1; at inlet and outlet of pumps N1, N-2/1, N2/2, N-3/1, N3/2 by sensors 521, 53-1, 541, 60-1, 611, 62-1, 631, 64-1, 651, 66-1; bearings of pumps N1, N-2/1, N2/2, N-3/1, N3/2 with instruments 671, 68-1. 691, 70-1, 711.

- pressure monitoring: at inlet and outlet of pumps N1, N-2/1, N2/2, N-3/1, N3/2 with devices 171, 18-1, 191, 20-1, 211, 22-1, 231, 24-1, 251; in the reflux tank by sensor 221; at the bottom of the column, sensor 211.

Development of structural diagram of asu tp

3.1 Main Features

The block diagram of a control system is submitted on sheet DP2068998A11100.00.000.E1 of a graphic part of the project and in figure 3.1.

The system has a two-level hierarchical structure. The lower level is represented by the SIMATIC S7 300 programmable controller, ET200M distributed I/O station with sensors and actuators connected to it, the upper level includes an automated workstation (AWS) of the operator and instrument engineer.

The structure of the management system was developed in accordance with the main trends in automation identified during the analytical review; and considering that the equipment room where the programmable controller is located is outside the area where the atmospheric distillation unit is located. A distributed I/O station is located directly in the site area. This fact allows all signals from sensors, actuators to be brought to the modules of the distributed I/O station, from where the signals are transmitted directly to the PC.

Design part

The MATLAB system includes the Simulink dynamic system simulation package. This package has extensive possibilities for implementing methods of automatic control theory when studying the dynamics of automatic systems. We will use the Simulink package for mathematical modeling of our system.

6.1 Investigation and adjustment of the control loop

The objective of the control system under investigation is to maintain constant pressure in the line of strictly reflux supply to the top of the stripping column with correction by the column top temperature.

The need for regulation is explained by the fact that the gasoline pressure directly determines the degree of heating of the top of the column, and the latter has a significant impact on the oil stripping process. The same fact defines the main requirements for the speed and accuracy of the control loop: gasoline vapors at the outlet of the column should be heated to a temperature of 150 ° C (gasoline evaporation temperature).

Pressure control with temperature correction consists in the fact that the specified value of gasoline pressure is calculated in each cycle of operation of the control program according to the procedure that takes into account the change in pore temperature (linear dependence is used). Since the real control effect is replaced by a single step signal in the course of the studies, no consideration of the fact of correction is required [11], and all the results obtained for the adopted system will be valid for the initial one .

Conclusion

During the diploma project, an automated system for controlling the process of atmospheric distillation of oil was developed.

The APCS hardware part is implemented in the form of a two-level system using Siemens Simatic hardware and software control tools. The lower level is the ET200M distributed I/O station, which controls the actuators of the unit (pumps, control and shut-off valves) based on the signals of discrete and analog sensors located on process equipment and pipelines; commands coming from AWS. The upper level is the operator's AWS of the atmospheric distillation unit, implements the operator's interaction with the control system and communication with the lower control level.

Algorithms for controlling the process of atmospheric distillation of oil, part of the control program in the STEP7Lite programming environment, an operator interface for AWS in an external LAN based on InTouch 8.1 were developed.

In the design part of the diploma project, the temperature control loop at the top of the stripping column was adjusted, with the results: type of transition process - aperiodic; transition time 7.39 s; phase stability margin 64.7 ° .

The diploma project gives the calculation of the economic effect from the introduction of ACS by the process of atmospheric distillation of oil - 4.77 million rubles. in the first year of operation, issues of life safety are considered.

The introduction of ACS by the process of atmospheric distillation of oil allowed:

expand automatic and automated monitoring and control functions;

increase reliability of emergency protection system operation;

improve the quality of process control;

reduce the number and time of localization of emergency situations and equipment failures.