How many steps are required to start up a refining and chemical processing plant?

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Pressure testing of equipment and piping systems (I) Conditions for pressure testing of piping systems: 1. The safety valves have been covered with blind plates, and the burst discs have been removed and also covered with blind plates. 2. The expansion joint has been fitted with a restraining device. 3. The spring supports and hangers have been locked. 4. When testing is conducted using water as the medium, the load-bearing capacity of the relevant structure has been confirmed or calculated. 5. The pressure gauge has been calibrated and found to be in good condition. (II) The following requirements must be complied with: 1. Pressure testing using air and process media must be approved by the production and safety departments. 2. Before the test, confirm that the test system has been effectively isolated from unrelated systems. 3. When conducting hydrostatic tests, clean fresh water shall be used as the testing medium; when austenitic stainless steel equipment or pipes are connected to the system, the chloride content in the water must not exceed 0.0025%. 4. The test temperature must be higher than the material’s brittle transition temperature. 5. When conducting tests in cold seasons, anti-freezing measures must be taken. 6. The hydraulic test pressure for steel pipelines is 1.5 times the design pressure ； When the design temperature is higher than the test temperature, the test pressure shall be calculated based on the ratio of the allowable stresses at the two temperatures, but it must not exceed the yield strength of the material. When testing with gas, the test pressure is 1.15 times the design pressure. 7. When the test pressure of the equipment in the test system is lower than that of the pipeline, and this equipment test pressure is not less than 115% of the pipeline’s design pressure, the pipeline system can be tested at the equipment’s test pressure. 8. When the test system is connected to equipment that can only withstand a certain pressure difference, it is necessary to ensure that this pressure difference does not exceed the specified value during the process of increasing or decreasing pressure. 9. During testing, the voltage should be increased slowly. When conducting tests with liquid, the pressure should be maintained at the test pressure for 10 minutes, and then reduced to the design pressure to check for leaks. When conducting tests with gas, a preliminary test should first be carried out at a pressure lower than 0.17 Mpa (gauge pressure); thereafter, the pressure is increased to 50% of the design pressure, then gradually raised to the test pressure and held at that level for 10 minutes. Finally, the pressure is reduced to the design level to check for leaks. 10. After the test is completed, the water and air should be drained, and the system should be returned to its original state. Leakage testing of equipment and piping systems (1) Leakage testing must be carried out when transporting toxic media, flammable media, or other media for which leakage testing is required according to design specifications. (II) The leak test should be conducted after the pipeline has been cleaned or purged successfully. (III) When conducting a pressure test using air, it can be carried out together with a leak test. However, after the pipeline has been cleaned or purged successfully, a final leak test must be performed; the main focus of this inspection is at the points where the pipeline was reassembled. (IV) The following requirements shall be complied with: 1. The test pressure shall not be higher than the design pressure. 2. The test medium is generally air. 3. The test pressure for the vacuum system’s leakiness is 0.01 MPa (absolute pressure). 4. Conduct inspections using the method specified in the design documents. Water flushing: (1) Only after the pressure test is successful, and after protective measures have been taken for the machinery, instruments, valves, etc. in the system, as well as after the temporary pipes have been installed and the flushing pump can operate properly, and after a filter has been installed at the inlet of the flushing pump, can water flushing be carried out. (II) If the flushing work is carried out in cold weather, anti-freezing and anti-slip measures must be taken. (III) During filling and draining, the piping system should be connected to the atmosphere. (IV) Before the pipelines and machinery in the previous process have been successfully flushed, the flushing water must not enter the machinery in the next process. (5) The rinse water should be discharged to designated locations. (VI) After flushing, ensure that all drainage and exhaust pipes are unobstructed. Steam purging (I) Conditions for steam purging: 1. The pipeline system has passed the pressure test. 2. According to the design requirements, locate the positions for pipe connections and splices, and install temporary pipes ； Pipeline safety standards shall meet the requirements of relevant specifications. 3. Effective protective measures have been taken for valves, instruments, and machinery. 4. Ensure that there are no flammable materials on or near the pipeline system, and that the pipelines carrying flammable materials are properly isolated to prevent fires in the event of a leak. 5. The steam supply system is now operating normally, and the steam volume can meet the requirements for purging. 6. Fencing has been installed around the restricted area, along with prominent signs. 7. The test operators are wearing the required protective clothing and shock-absorbing earplugs. (II) The following regulations must be observed: 1. Steam purging is strictly prohibited for pipeline systems that have not taken expansion into account. 2. Before steam purging, warm the pipes by opening all drain pipes to remove condensate and prevent water hammer. 3. During purging, blow through each drain pipe one by one. 4. Conduct a thorough inspection of the reset process to ensure that the pipeline system has been fully restored, and that the connections between pipes and machinery are freely aligned in accordance with the specified standards. 5. Noise reduction measures must be in place for purging. Chemical cleaning (I): The interior of the pipeline system is free of debris and oil stains. (II) The chemical cleaning solution has been analyzed by the quality inspection department and found to meet the standard requirements; thus, it is confirmed that it can be used for the system to be cleaned. (III) There shall be a chemical cleaning flow diagram and a blind flange location diagram. (IV) The facilities, heat sources, chemicals, analytical instruments, tools, etc., required for chemical cleaning are all available. (5) The chemical cleaning personnel are dressed in accordance with protective regulations and are wearing protective equipment. (VI) If the pipeline system after chemical cleaning cannot be put into use temporarily, it should be protected with an inert gas. (7) Sewage must be treated to meet environmental protection standards before it can be discharged. Air purging (1) Pipes with a diameter greater than 600 mm should be cleaned manually. (II) The system has passed the pressure test, and effective protective measures have been taken for the machinery, instruments, valves, etc. within the system. (III) The location of the blind flange has been confirmed, and the gas supply is guaranteed ； When purging oil-free pipelines, the air must be free of oil. (IV) Strict inspection should be carried out on the reset operation after purging. (5) Measures such as shielding, warning signs, prevention of occupancy, and noise protection must be taken during purging. Pre-film formation in the circulating water system (I) Conditions for pre-film formation in the circulating water system: 1. The system has been flushed with water and is qualified. 2. The circulating water system passed the joint commissioning test. 3. Tests have confirmed that the liquid chemical is suitable for the on-site water quality; it exhibits good film-forming effects, and its corrosiveness is lower than the specified design limits. 4. Test pieces for observing the pre-film condition have been properly installed in the system as required. 5. Effective measures have been taken to handle waste liquid. (II) The following regulations shall be observed: 1. Pre-coating work should be carried out away from the cold seasons; if it must be done during such periods, anti-freezing measures are necessary. 2. The pre-coating process of the system should be completed in one go; no pipes or equipment that have not been pre-coated should remain within the system. 3. After pre-coating, chemicals should be applied on time and in the correct amount to keep the system in a coated state. System displacement (I) – Inert gas displacement: Before introducing combustible gases into the testing system, the air must be displaced by inert gases, and then the inert gases should be replaced with combustible gases. Before stopping the system for maintenance, the flammable gases within it must be replaced with inert gases, which should then be replaced with air. Attention must also be paid to the proper handling of toxic and hazardous solids and liquids. (II) System replacement conditions: 1. A flow diagram showing the locations of the vent points, analysis points, and blind plates for replacement. 2. The sampling and analysis personnel are in place, and the analysis instruments and reagents are ready. 3. Inert gases can meet the requirements of displacement work. (III) The following regulations must be complied with: 1. The oxygen content in inert gases shall not exceed the safety standards. 2. Verify that the quantity, quality, and installation location of the blind plates are satisfactory. 3. When performing displacement, attention should be paid to the dead corners in the system; if necessary, the method of repeated pressure increase and decrease can be used to dilute the displacement gas. 4. When the pipeline system is connected to a gas holder, the gas holder should be raised and lowered three times to completely displace the gas in the annular water seal. 5. The replacement work should be carried out sequentially, starting with the main pipes and then moving on to the branch pipes. 6. When taking samples, analysts should pay attention to the wind direction as well as the height and direction of the vent pipes to prevent poisoning. 7. The data shall be analyzed on the basis of three consecutive successful tests, and must be signed off by the personnel in charge of production, technology, and safety. 8. After the displacement is complete, effective measures shall be taken to isolate the inert gas pipeline from the system. (IV) Qualification criteria: 1. When replacing flammable gases with inert gases, the concentration of flammable gases in the gas after replacement shall not exceed 0.5%. 2. When replacing inert gas with combustible gas, the oxygen content in the replaced gas must not exceed 0.5%. 3. When replacing air with an inert gas, the oxygen content in the gas after replacement must not exceed 1%; if the gas is to be introduced directly into flammable or explosive media, the oxygen content in the gas after replacement must not exceed 0.5%. 4. When replacing inert gas with air, the oxygen content in the replaced gas must not be less than 20%. General testing of electric motors (I) Conditions for general testing of electric motors 1. The pipelines and equipment related to the motor testing have been purged or cleaned to meet the required standards. 2. Filters are installed at the machine inlet as required. 3. The sealed oil pipelines and equipment for pressure lubrication have been successfully oil-cleaned and undergone trial operation. 4. The protective interlocks, early warning systems, indicators, and automatic control devices for motors and machines have been successfully commissioned. 5. The safety valve has been successfully commissioned. 6. The rotation direction of the motor has been verified, and the motor grounding is satisfactory. 7. The equipment protective cover has been installed. (II) The following regulations shall be complied with: 1. The medium used for testing shall conform to the provisions in the design documents; unless otherwise specified, water should be used as the medium for pumps and mixers, while air or nitrogen should be used as the medium for compressors and fans. 2. Water should not be used as the testing medium for cryopumps; otherwise, the water must be completely drained after testing, and the pump must be thoroughly dried and inspected to ensure it is in good condition. 3. When the specific gravity of the testing medium is greater than that of the designed medium, attention should be paid to the motor current during testing to ensure it does not exceed the specified value. 4. The machine must be rotated before testing. 5. The machine can be tested only after the motor passes the test. 6. The machine should generally be tested without load first, and then under load. 7. During testing, attention should be paid to checking the temperature of the bearings (bushings) and packing, the vibration of the machine, the current level, the outlet pressure, and the filter screen. 8. Instrument indications, alarms, automatic control, and interlocks shall be accurate and reliable. Filling of tower and vessel internals (I) Conditions for filling tower and vessel internals 1. The pressure test of the tower and vessel system must be successful. 2. The interiors of towers, vessels, etc. are clean and free of debris; the concentration of toxic and flammable substances inside the equipment that has undergone anti-corrosion treatment meets relevant standards. 3. Towers and vessels with linings, whose linings have passed inspection. 4. The manholes and vent pipes have been opened, ensuring good ventilation inside the tower and vessels. 5. The filler has been cleaned thoroughly. 6. All filling tools are available. 7. A permit for working in confined spaces has been obtained. 、 (II) The following rules must be observed: 1. Persons entering the tower shall not bring any items that are not related to the filling work. 2. Personnel entering the tower shall wear appropriate clothing and protective equipment as required, and a dedicated person shall be assigned to supervise them. 3. Unqualified internal components and fillers mixed with contaminants must not be installed. 4. When installing the tray, the installer should stand on the beam. 5. The installation of distributors, tray plates and their accessories, as well as the arrangement of the packing, must all be carried out in strict accordance with the provisions of the design documents; professional technicians shall review these elements and record them for archiving. 6. Before sealing the tower and vessels, all tools and unnecessary items carried with one should be removed completely, and a leakage test should be conducted after sealing. Filling of catalysts, molecular sieves, etc. (I) Conditions for filling catalysts, molecular sieves, etc. 1. The type, specifications, and quantity of the catalysts meet the design requirements, and they are in good condition. 2. The pressure tests of the reactor and related systems have passed. 3. The reactor with a heat-resistant lining has passed the furnace drying test. 4. The interior of the reactor is clean and dry. 5. All filling equipment and facilities are available. 6. A permit for working in confined spaces has been obtained. (II) The following regulations must be observed: 1. Persons entering the reactor shall not bring in any items that are not related to the filling work. 2. When filling the catalyst, a dedicated person must be assigned to supervise. 3. Filling personnel must wear the required clothing and protective masks. 4. Unqualified catalysts (ground, crushed, etc.) must not be placed inside the container. 5. During filling, the free fall distance of the catalyst shall not exceed 0.5 meters. 6. The filling personnel must not stand directly on the catalyst. 7. The filling work shall be carried out strictly in accordance with the provisions of the filling plan. 8. For parallel reactors, check the pressure drop to ensure even airflow distribution. 9. After filling, the pre-reduction catalyst should be protected with an inert gas, and a dedicated person should be assigned to monitor changes in the catalyst’s temperature. 10. A leak test should be conducted after the reactor is reset. Re-inspection of the heat exchanger (I): After the heat exchanger arrives at the site, a leak test must be conducted again; when specified, a core pulling inspection should also be carried out. (II) The water or chemicals used for testing shall meet the requirements of the tests. (III) During testing, water should be injected between the pipes and pressure applied; special attention should be paid to the expansion joints or welds to ensure that they remain within normal limits. (IV) If a leak is detected within the pipeline, a core extraction inspection should be carried out. (5) If inspection using ammonia or other media is required as stipulated, the special provisions shall be followed. (VI) After inspection, any accumulated water should be drained and dried with air. Instrument system commissioning (I) Conditions prior to instrument system commissioning: 1. The instrument air station is in proper operating condition, and the instrument air pipeline system has been properly purged. 2. The air conditioning and uninterruptible power supply in the control room are functioning properly. 3. The individual calibration of transmitters, indicating and recording instruments, signaling switches for interlocks and alarms, control valves, as well as panel-mounted and rack-mounted instruments has been completed. 4. The relevant parameters of the regulator in the automatic control system have been preset; the feedforward control parameters, ratio values, and various correction ratio offsets have been calculated and set according to the relevant data. 5. All types of analog signal generators, testing instruments, standard gas samples, communication devices, etc. are available. 6. All on-site instruments and control valves are in operation. 7. For key equipment and critical positions that fall under the category of (one major and two key items), it is necessary to first test the automatic interlock and alarm systems separately to ensure they are in good working condition. (II) The following requirements shall be complied with: 1. Before conducting joint tests with the machinery, the testing and automatic control systems must first undergo simulated debugging; that is, simulated signals are inputted at the transmitters, and all functions related to input processing, manual/automatic switching, and output processing are checked and adjusted on the control panel or secondary instruments. 2. The interlocking and alarm systems should undergo simulated debugging prior to mechanical joint testing; that is, simulate signals are input at the signal sending switches to check their logical correctness and operating performance, and adjustments are made until they meet the required standards. 3. When calibrating instruments in conjunction with mechanical tests, instrument technicians, electrical engineers, and process operators must work closely together and coordinate their efforts. 4. For interlock devices that are being tested for the first time or cannot be put into use under load temporarily, they may be temporarily disconnected with the consent of the construction (production) unit, but the alarm devices must remain in place. 5. Before starting up the chemical plant after feeding in the materials, it is necessary to re-tune the various parameters for the feedforward control, proportional control, and control systems with correctors, based on the load level and the actual composition of the materials. Electrical system commissioning (I) Conditions prior to electrical system commissioning: 1. Isolators, load switches, high-voltage circuit breakers, insulating materials, transformers, instrument transformers, silicon rectifiers, etc., have been successfully commissioned. 2. The insulation resistance of the relay protection system and secondary circuits has been tested for voltage withstanding capacity and adjusted accordingly. 3. Test report for high-voltage electrical insulating oil is required. 4. It should have records of battery charging and discharging curves as well as laboratory test reports for the electrolyte. 5. Test records for lightning protection and protective grounding resistance are available. 6. Have test qualification records for motors and cables. 7. Have records of successful cascade protection tests. (II) The following regulations must be observed: 1. Power supply and distribution personnel must work in accordance with established procedures and strictly follow the operating protocols. 2. Before receiving power, the substation must conduct simulated tests on the relay protection devices, automatic reclosing devices, alarm systems, and phase prediction systems in accordance with the system requirements. 3. The protection devices for programmable logic controllers should simulate each interlock and alarm parameter individually, and the correctness of the positive alarm values of their logic should be verified. 4. The test run and verification of the emergency power supply system should be carried out. 5. Operations must be carried out in accordance with the prescribed procedures for shutting down and restoring power supply. 6. The electrical system should be inspected and accepted before power is supplied. The commissioning of key equipment shall meet the following conditions: (1) The pressure test of the system pipelines and the airtightness test of the heat exchange equipment must be successful. (II) The process and steam pipelines have passed purging or cleaning inspections. (III) The lubricating oil, seal oil, and control oil systems for mechanical equipment have been cleaned to meet the required standards. (IV) The safety valve has been tested and found to be in good condition, and it has been sealed with lead. (5) The electrical systems, instruments, automatic interlock controls, alarm systems, computers, etc., related to the test run have been successfully calibrated and tested. (VI) The power required for testing, instrument air, circulating water, deionized water, and other fluids are in place. (7) The test run plan has been approved, and the command, operation, and maintenance personnel are in place. Testing instruments, tools, protective equipment, and record forms are all ready. (IX) The test area has been designated, and relevant personnel may enter with proper authorization. (10) Determination of test run technical specifications