Safety technical regulations for production of oxygen and related gases by deep cooling method (2)

5 General requirements for production operation and equipment | Oxygen Compressor Company
4.1 The equipment should be installed, operated, inspected, maintained and tested according to the national and industry standards and the technical documents of the manufacturer.
5.2 All equipment, pipelines, valves, instruments and parts in contact with oxygen are strictly prohibited from being contaminated with grease. Oxygen pressure gauges should be provided with oil-free signs.
5.3 The tools, work clothes, gloves and other supplies used by the personnel who operate, maintain and overhaul the oxygen production system are strictly prohibited from being contaminated with oil.
5.4 The utensils containing cryogenic liquids should be clean, and it is strictly forbidden to accumulate oil, water, organic matter and other impurities in the container.
5.5 Wear protective equipment when preparing and handling corrosive chemicals.
5.6 It is not allowed to pile up grease and other items not related to production on the production site.
5.7 It is strictly forbidden to pile up flammable and explosive materials around the air separation unit, liquid oxygen tank and the main control room, and it is not allowed to randomly dump harmful pollutants.
4.8 Before driving, check the safety protection devices, instruments and meters of the equipment, and confirm the opening and closing status of the valve.
5.9 The pressure gauges, safety valves, thermometers and other instruments and safety interlock protection devices in the calibration system should be checked regularly.
4.10 Intermediate cut-off valves should not be installed between the storage tank and the safety valve. If necessary, a shut-off valve of the same level can be installed, but the shut-off valve should be kept fully open during normal operation, and lead sealed, locked and tagged.
4.11 When working in nitrogen, gas and other rare gas areas, measures to prevent suffocation should be taken, and the gas in the working area can only be allowed to work after passing the laboratory test.
4.12 Before starting the rotary equipment, the cranking inspection should be carried out according to the requirements of the equipment operating regulations, and it is strictly forbidden to start while cranking.
4.13 The exposed rotating parts of the equipment shall be equipped with protective covers that meet the relevant national standards. It is strictly forbidden to step over the equipment in operation.
4.14 Carry out roving inspections of the equipment in operation according to the regulations, deal with and report problems in time if any problems are found, and stop the machine for processing in case of emergency.
1215 In cold weather, antifreeze measures should be taken for the equipment.
4.16 Overpressure operation of compressors, storage tanks (including cryogenic liquid storage tanks) and other related equipment is strictly prohibited. If there is any leakage in the equipment or system, it is strictly forbidden to use compression bolts.
4.17 It is forbidden to discharge various gases other than air into the room.
4.18 Before the oxygen storage tank is put into use, pressure test, air tightness test, rust removal, degreasing, purging should be carried out, and non-combustible anti-rust paint should be painted on the inner wall.
4.19 When releasing oxygen and discharging liquid oxygen and liquid air, the surrounding area should be notified that fire is strictly prohibited, and special personnel should be assigned to monitor.
6 Oxygen production and equipment
5.1 Air compressor
5.1.1 The air filter at the inlet of the air compressor should be regularly cleaned or replaced according to regulations. The air compressor inlet should not use oil-immersed filters.
5.1.2 Large and medium-sized air compressors should be equipped with alarm interlocking devices for anti-surge, vibration, shaft displacement, oil pressure, oil temperature, water pressure, water volume, bearing temperature and exhaust temperature. An airdrop test should be done before driving.
5.1.3 For large and medium-sized air compressors not equipped with a shaft head oil pump, it is advisable to install a high-level oil tank or a pressure oil tank, and an interlock protection device for the auxiliary oil pump to start and stop when the oil pressure drops.
4.1.4 If any abnormal sound, smell, vibration or failure occurs during the operation of the air compressor, it should be stopped immediately for inspection.
5.1.5 All protective interlocking devices and safety accessories of the air compressor should be checked before starting, and can only be started after confirming that they are in good condition.
5.1.6 The continuous cold start of large and medium-sized air compressors should not exceed three times, and the hot start should not exceed two times. The start-up interval shall be carried out according to the equipment operation manual.
5.1.7 The oil filling volume and oil quality of the piston air compressor cylinder should meet the requirements, and the temperature of the cylinder should be strictly controlled to not exceed the specified value. The flash point of the cylinder lubricating oil should be higher than the normal discharge temperature of the compressor air by more than 40 cu, and it should have good anti-oxidation stability.
5.1.8 The booster for the internal compression process (oxygen) should meet the requirements of 6.1.2-6.1.6.
5.1.9 The supercharger and the main air compressor of the internal compression process (oxygen) should run synchronously, and the interlock protection device between the supercharger and the main air compressor should be perfect and reliable.
6.2 Oxygen Compressor
5.2.1 The oxygen compressor inlet should be equipped with an oxygen filter that can be cleaned regularly, and the oxygen filter should meet the requirements of 8.4.4.
5.2.2 During the test run of the oxygen compressor, nitrogen or oil-free air should be used for purging and test run, and direct test run with oxygen is strictly prohibited.
6.2.3 The shaft seal of the turbine oxygen compressor should be intact, and the pressure of the shaft seal gas should be within the specified value.
6.2.4 The turbo oxygen compressor shall prevent the cooler from leaking. When shutting down for a long time, it should be filled with nitrogen and sealed.
6.2.5 The turbo oxygen compressor should be equipped with fusible probe or temperature probe, automatic rapid nitrogen fire extinguishing or other fire extinguishing measures.
6. 2.6 Regularly check the sealing effect of the oil sealing ring of the piston type oxygen compressor, and repair it in time if any problem is found, and strictly prohibit oil from being brought into the cylinder by the piston rod.
6.2.7 When the oxygen compressor is working normally, the pressure and temperature at all levels must not exceed the specified value. When there are abnormal vibrations and sounds, measures should be taken until the machine is shut down for inspection.
6.2.8 Oxygen compressors with water-lubricated cylinders should be equipped with a water cut-off alarm stop device. During operation, the supply of distilled water should be checked frequently, and water shortage and water cut-off are strictly prohibited.
6.2.9 When opening the manual oxygen valve, it should be opened slowly sideways. If there is a bypass valve, the bypass valve should be opened first to equalize the pressure, and measures should be taken immediately if any abnormal sound is found.
5.2.10 When the oxygen compressor is on fire, it should be shut down urgently and the oxygen source should be cut off at the same time, and an alarm signal should be sent.
6.2.11 The materials of all parts of the oxygen compressor should meet the original design requirements. It is strictly forbidden to arbitrarily change the material of oxygen compressor parts before obtaining sufficient test data to prove that alternative materials are available.
6.2.12 The oxygen compressor should also implement the relevant provisions of 6.1.
6.3 Expander
6.3.1 A filter should be installed at the inlet of the expander and cleaned regularly.
6.3.2 The turbo expander shall have a differential pressure interlocking protection device for sealing gas pressure and oil pressure. The oil pump can only be started when the sealing gas pressure is adjusted to the specified value.
6.3.3 When the nozzle is blocked by ice, carbon dioxide, etc. during operation, stop the machine immediately and heat it to thaw. During the thawing process, oil supply and sealing gas are still required. The heating and thawing of the air bearing turboexpander shall be carried out according to its operation manual.
6.3.4 When the expander has overspeed, abnormal sound, low oil pressure, high bearing temperature, etc., the inlet valve should be closed quickly, and the machine should be stopped for inspection and treatment.
6.3.5 The turbo expander should be equipped with an overspeed alarm and automatic shutdown device, and an emergency shut-off valve should be installed before the entrance. The tachometer should be calibrated regularly.
6.3.6 When the static pressure air bearing turbo expander starts and stops, it should be carried out slowly. The operation process of boosting the pressure when starting up or reducing the pressure when stopping should be controlled within 1 min-2 min. It is strictly forbidden to resonate in the pipeline Click to stay. If the bearing air pressure is too low, it should be stopped for emergency inspection.
6. 3.7 The inlet temperature of the non-entrained expander shall be within the normal range, the temperature of the gas after expansion shall maintain a certain degree of superheat, and the temperature after the machine shall be strictly controlled to ensure that the gas does not liquefy.
6. 3.8 For the expander with fan brake, it is forbidden to close the inlet and outlet valves of the fan during operation. The air filter at the brake fan inlet should be cleaned regularly.
6.3.9 The anti-runaway device of the piston expander should be intact and reliable. When the power fails suddenly or the piston expander stops, the high-pressure gas inlet valve should be closed first.
6.3.10 The booster turbo expander shall be provided with anti-surge protection device.
6.4 Liquid oxygen pump
6.4.1 A filter should be installed at the inlet of the liquid oxygen pump.
6.4.2 The liquid oxygen pump should be equipped with an audible and visual alarm and an automatic shutdown device for outlet pressure and bearing temperature.
6.4.3 Before starting the liquid oxygen pump, it should be purged with dry air or nitrogen and then cranked for inspection. Before driving, the sealing gas should be opened first, the pressure of the sealing gas should be within the specified range, and it should be started after sufficient precooling. No liquid oxygen leakage is allowed during operation. The liquid should be drained immediately after shutdown, and it should be thawed after standing still.
6.4.4 Liquid oxygen pump bearings should use special grease, and strictly control the amount of oil added, clean the bearings and replace the grease according to the specified time.
6.4.5 A safety protection interlock device should be installed between the medium and high pressure liquid oxygen pump and the vaporizer.
6.5 Air separation unit | Oxygen Compressor Company
6.5.1 In order to prevent the accumulation of ethylene in the liquid oxygen of the air separation unit, it is advisable to continuously extract part of the liquid oxygen from the air separation unit, and the amount is not less than 1% of the oxygen production.
6. 5.2 The content of harmful impurities such as acetylene, hydrocarbons and grease in the liquid oxygen should be tested regularly. The B group content in the liquid oxygen of large and medium-sized oxygen generators should not exceed 0. IX10-6, and the content of small oxygen generators should not exceed 1.0X 10-6, and should be discharged if it exceeds; The total hydrocarbon content should not exceed 1OOX1O-8, and should be discharged if it exceeds; large-scale air separation falling film main cooling should also monitor nitrous oxide. In addition, it should be carried out strictly in accordance with the equipment operating instructions and the safety technical operating procedures of the production unit.
6. 5.3 When discharging liquid oxygen, liquid nitrogen, liquid air or liquid oxygen, it should be gasified and discharged into the air and discharged to a safe place.
6.5.4 The immersion-type main cooling should be fully immersed, and the main cooling liquid level should be strictly controlled to avoid large fluctuations.
6.5.5 The air precooling system should be equipped with an air cooling tower water level alarm interlock system and an outlet air temperature monitoring device.
6. 5.6 All kinds of adsorbers should be regenerated according to the specified service cycle, and if the impurity content exceeds the standard, they should be replaced in advance.
6. 5.7 The regeneration system should be strictly implemented during the operation of the molecular sieve adsorber, and the working cycle of the adsorber is not allowed to be extended arbitrarily. A carbon dioxide monitor should be installed at the outlet of the molecular sieve adsorber, and a trace water analyzer should be installed. Regeneration temperature, gas volume, and cold blowing temperature should be controlled according to regulations, and a trace water analyzer should be installed at the exhaust outlet of the steam heater.
6.5.8 For reversible heat exchangers or cold accumulators, the resistance, temperature difference between the middle part and the cold end should be controlled within the specified range, and there should be enough backflow gas to ensure the self-cleaning effect.
6.5.9 The Jingyi tower, adsorber and heat exchanger of the medium and high pressure air separation unit should be discharged, brushed and cleaned regularly according to the actual situation, and the cycle should be shortened if the oil is serious.
6.5.10 During the operation process, the process parameters such as temperature, pressure, flow rate and liquid level should be kept relatively stable, avoid rapid and large increase or decrease of air volume, oxygen volume and nitrogen volume, and prevent faults such as liquid flooding.
6.5.11 The air separation cold box should be filled with dry nitrogen to maintain positive pressure and checked frequently. Large and medium-sized air separation cold boxes should be equipped with positive and negative pressure gauges, breathing valves, explosion-proof plates and other safety devices.
6.5.12 If the explosion-proof plate on the air separation cold box moves or pearlescent sand is sprayed out, it should be checked immediately and stopped for treatment if necessary.
6.5.13 When the air separation unit shuts down in an accident, the oxygen and nitrogen product delivery valves should be closed immediately, and an automatic signal should be sent to the relevant posts.
6.6 Thawing and blowing off of air separation unit
6.6.1 When the air separation unit is thawed and shut down, the liquid should be drained, and it can be heated with hot gas after standing still and blown cold, and the heating temperature should be controlled according to the equipment operation manual.
6.6.2 The heating of the air separation unit should be carried out with oil-free dry air or nitrogen, and the pressure of the heating gas should be controlled within the specified range.
6. 6.3 When the air separation unit is heated up, the temperature should be raised slowly. When heating, a special person should be responsible for monitoring the temperature and pressure. Overheating and overpressure are strictly prohibited, and the requirements of 9.2.14 should be met.
6.6.4 When the air separation unit uses nitrogen for large-scale heating or partial heating of monomers, a warning sign should be hung, and no one is allowed to stay near the discharge port.
6.6.5 When heating the pearlite in the cold box, no one is allowed to stay, check or repair in the cold box, and special measures should be taken if necessary.
6.6.6 The blow-off operation should be carried out in sections to ensure that all small pipes such as analysis valves, pressure gauges, liquid level gauges, resistance gauges and blow-off valves are unimpeded until the blown gas is clean and free of dirt. Before cold start-up, spot check that the dew point of the gas exhausted by the above-mentioned valves is not higher than -45°C.
6.7 Cryogenic liquid storage, delivery and vaporization system
6.7.1 Keep the vacuum degree of the interlayer of the powder vacuum insulation cryogenic liquid storage tank so that the absolute pressure is in the range of 1.36 Pa~6. 80 Pa.
6.7.2 For powder insulation cryogenic liquid storage tanks, the insulation layer shall be filled with oil-free dry nitrogen, and positive pressure shall be maintained. Cryogenic liquid storage tanks should regularly inspect the safety valve, the breathing valve of the inner and outer cylinders, the constant pressure exhaust regulating valve, and the sealing gas regulating valve between the inner and outer cylinders.
6.7.3 It is strictly prohibited that the operating pressure of the cryogenic liquid storage tank exceeds the designed working pressure. For powder insulated flat-bottom cryogenic liquid storage tanks, the breathing valve should be kept intact, and the liquid discharge speed should be controlled to prevent negative pressure in the tank from causing deflation of the liner.
6.7.4 The ethanol content in the liquid oxygen in the liquid oxygen storage tank should be tested at least once a week. When the value exceeds 0.1X10Y, the air separation unit should continuously deliver liquid oxygen to the storage tank to dilute the ethane concentration to less than 0.1X10- ', and start the liquid oxygen pump and gasification device to transport outward.
6.7.5 Cryogenic liquid oxygen storage tanks should be heated and purged regularly to completely remove harmful impurities such as hydrocarbons. Before using the liquid oxygen storage tank, it should be cleaned with oil-free dry nitrogen, and the gas dew point in the tank should not be higher than -45 °C before it can be put into use.
6.7.6 The outlet of the low-temperature liquid vaporizer should be equipped with an interlock device for low temperature alarm, and the gas temperature at the outlet of the vaporizer should not be lower than -10 °C.
6.7.7 The water level of the water bath vaporizer should not be lower than the specified line. A water temperature adjustment control system should also be set up, and the water temperature should be kept above 40 °C. For water-bath vaporizers, the coils should be regularly checked for leaks, and the water temperature of the vaporizer, the outlet gas temperature, and the pressure interlock alarm device should be checked regularly.
6.7.8 When dew condensation occurs on the outer cylinder of the cryogenic liquid storage tank, the cause should be found out, the pearlite sand should be supplemented or replaced for the atmospheric pressure storage tank, and the vacuum insulation storage tank should be vacuumed to eliminate the fault.
When a large area of ​​condensation or frost occurs on the outer cylinder of the low-temperature liquid storage tank, stop using it immediately, drain the liquid and heat it to normal temperature, reliably cut off the pipeline connecting the storage tank and the outside, and check for leaks. When entering the container for maintenance, the regulations in 9.1.2 and 9.1.5 should be followed.
6.7.9 The safety valve of the vacuum pipeline should be checked regularly. When the vacuum pipeline and vacuum hose have a large area of ​​frost, it is not suitable to continue to use it.
6.7.10 The maximum filling capacity of the cryogenic liquid storage tank is 95% of the geometric volume.
6.7.11 The check valve at the outlet of the cryogenic liquid pump should be inspected and adjusted regularly.
6.8 Tanker transportation of liquid oxygen, liquid nitrogen and liquid chlorine
6.8.1 The liquid oxygen tanker shall comply with the relevant regulations in the "Safety Supervision Regulations for Liquefied Gas Vehicle Tanker" and JB 6898.
6.8.2 The liquid oxygen tank car should be equipped with safety devices such as safety valve, liquid level gauge, pressure gauge, explosion-proof disc and static electricity.
6.8.3 Before the tank car is filled with liquid oxygen for the first time, it should be purged with oil-free dry nitrogen and fully pre-cooled. Filled liquid oxygen should not exceed 90% of the storage tank volume. The joint hose should be dedicated, and oil pollution is strictly prohibited.
6.8.4 Spillage should be prevented when filling liquid oxygen, and special personnel should be present to monitor, and the tank truck should be in a flame-off state during the filling process.
6.8.5 The moving liquid oxygen tanker should avoid the downtown area and densely populated areas, and drive at a limited speed. Do not stop when you must pass through downtown and densely populated areas.
6.8.6 When the liquid oxygen tanker is running, the pressure in the tank should be monitored, and it is strictly forbidden to exceed the specified value. When releasing liquid oxygen, the discharge rate should be controlled. When there is liquid oxygen in the liquid oxygen tank car, it is not suitable to repair the car.
6.8.7 The liquid oxygen in the liquid oxygen tank should not be stored for a long time, let alone mixed with other liquids, and the paint color mark should comply with relevant regulations*
6.8.8 The vacuum degree of the insulation layer of the liquid oxygen tanker should be monitored. When frost forms on the surface and the vacuum degree drops, it should be dealt with in time, and stop using if it is serious.
6.8.9 The requirements for liquid nitrogen and liquid oxygen tank trucks should refer to the relevant regulations for liquid oxygen tank trucks.
6.9 Oxygen and related gas filling
6.9.1 The filling and management of gas cylinders shall comply with the relevant regulations in the "Gas Cylinder Safety Supervision Regulations" and GB 14194, and shall be approved by the special equipment safety supervision agency. Pretend to work. The gas cylinder filling unit should have a management system and various management systems to ensure filling safety, have management personnel familiar with the gas cylinder filling safety technology and professionally trained operators, and have a place suitable for the gas to be filled. , facilities, equipment and testing means.
6.9.2 Gas cylinders must be inspected by special personnel before filling, and those who have one of the following situations should be dealt with, otherwise filling is strictly prohibited:
a) The paint color, characters and the gas contained therein do not meet the requirements or the paint color and characters fall off and the type of the gas cylinder cannot be identified;
b) Incomplete, damaged or non-compliant safety components;
c) It is impossible to determine what kind of gas is contained in the bottle or there is no residual pressure in the bottle;
d) Incomplete or unidentifiable steel stamps;
e) Exceeding the inspection period;
f) The bottle body is defective after visual inspection, and safe use cannot be guaranteed;
g) The bottle body and bottle valve are stained with grease or deformed;
h) The hydrogen and other combustible gas cylinders are filled for the first time without nitrogen replacement and vacuuming.
6.9.3 When filling gas cylinders, the following regulations shall be complied with:
a) Set up a filling overpressure alarm device to ensure that the pressure when the gas cylinder is filled to the equivalent of 20 °C does not exceed the allowable working pressure of the gas cylinder;
b) Pressure gauges and safety valves should be calibrated regularly to keep them sensitive and accurate;
c) There should be a residual pressure of 0.05 MPa or more in the bottle after use;
d) The filling speed of the gas cylinder shall not be greater than 8 m3/h, and the filling time shall not be less than 30 minutes. The opening and closing of valves should be carried out slowly, all parts of the filling field should be prohibited from oil, and fireworks are strictly prohibited;
e) The tools, joints and valves used in the oxygen filling station shall be made of copper;
f) The sealing material used for filling is made of non-combustible and non-sparking materials;
g) It is strictly forbidden to repair or twist the parts of the gas cylinder under pressure;
h) When the filling room or the oxygen cylinder catches fire, the source of oxygen should be cut off immediately, actively organize rescue, and report to the relevant department;
i) When filling oxygen, nitrogen, gas, hydrogen and other gases, no gas leakage is allowed;
j) In order to limit the filling speed of gas cylinders, the number of gas cylinders filled in the same batch is not allowed to be reduced arbitrarily, nor is it allowed to insert empty cylinders for filling in the middle of filling;
k) During the filling process of the gas cylinder, the method of touching the bottle wall with hands should be used to check whether the temperature of the bottle wall is normal, and stop filling immediately if there is any abnormality;
l) Oxygen and hydrogen should use anti-mistake joint filling fixtures to prevent mixed filling and mixing of combustible gases and combustion-supporting gases. Oxygen and nitrogen are not allowed to use the same filling line, and mixing of oxygen and nitrogen should be prevented;
m) There should be a reliable filling contact signal between the filling room and the gas compression room, and there should be an emergency stop button for the compressor in the filling room;
n) Lighting lamps and other electrical devices in the filling room filled with hydrogen should be explosion-proof;
O) The ground of the filling room should be flat, wear-resistant and non-slip;
P) For hydrogen and oxygen produced by electrolysis, the system of regularly measuring the purity of hydrogen and oxygen should be strictly implemented. When the volume ratio of oxygen in hydrogen or hydrogen in oxygen exceeds 0.5%, filling is strictly prohibited, and the reason should be found out at the same time.
6.9.4 Filling of hydrogen and oxygen should not be set in the same workshop filling station. There should be an emergency shut-off valve outside the oxygen filling station.
6.10 Gas cylinder management
6.10.1 Units that transport, store and use gas cylinders should strengthen the safety management of inspection, transportation, storage and use of gas cylinders:
a) There is a special person responsible for the safety of gas cylinders;
b) Formulate the corresponding safety management system according to the relevant provisions of the "Gas Cylinder Safety Supervision Regulations";
c) Formulate emergency rescue plans for accidents;
d) Regularly conduct safety technical education for gas cylinder transportation (including loading, unloading and driving), storage and use personnel;
e) Gas cylinders should adopt information management such as bar codes.
6.10.2 Regular inspection
a) The gas cylinder periodic inspection unit shall comply with the provisions of GB 12135, and the gas cylinder periodic inspection unit and inspectors shall obtain corresponding qualification certificates according to the regulations.
b) Gas cylinders filled with oxygen, nitrogen, oxygen and hydrogen should be strictly and regularly inspected one by one according to national standards such as GB 13004, GB/T 9251, GB/T 12137, GB 10877 and GB 7144. Gas can continue to be filled.
c) After inspection, the gas cylinders that do not meet the standards should be scrapped, and the scrapped gas cylinders should be destructively disposed of by crushing or sawing.
6.11 Instrument control system
6.11.1 When the distributed control system is adopted, a stop button should be set on the spot.
6.11.2 Before new equipment is put into production or after maintenance, testing and simulation tests should be carried out according to the process requirements to ensure that various interlocking controls meet the control requirements. The valve switch is in place to ensure that various interlock protection control actions are sensitive and reliable.
6. 11.3 After the process configuration of the control system, a functional test should be carried out to confirm that the automatic control alarm interlock system is sensitive and reliable before it can be put into use.
6. 11.4 The control cable should be shielded as required, the wiring should be firm, the static electricity should be guided, the grounding resistance should be less than 4, and the insulation should be good. Cables should avoid high temperature and humidity, and should be checked regularly.
6.11.5 All kinds of transmitters should not be installed in places with large temperature difference and large vibration.
6. 11.6 In the production process, the hardware settings should not be changed arbitrarily (such as the module is offline, etc.), and the software is not allowed to be modified without permission.
6. 11.7 For equipment of the distributed control system and analytical instruments with microprocessors, the working environment temperature shall be lower than 30 °C, and the temperature of the cabinet shall be lower than 40 °C.
6.11.8 The uninterruptible power supply (UPS) required by the distributed control system should be in normal state at all times.
6. 11.9 Regularly check the instrument, and check the operation of the instrument frequently, and no over-range operation is allowed. It is strictly forbidden for irrelevant personnel to tamper with the instrumentation equipment.
6.11.10 When calibrating oxygen and hydrogen analyzers, fireworks are strictly prohibited in the room, and oxygen and hydrogen standard gas cylinders should be placed at a certain distance.
6. 11. 11 Regularly check all interlocking devices and emergency parking devices in the system, and ensure that they are in good condition.
6. 11. 12 When interlocking stops during driving or operation, the cause should be carefully checked, and the interlocking and protection setting should not be canceled arbitrarily.
6. 11. 13 Analytical instruments
a) The standard gas cylinder room of the analytical instrument should be separated from the analytical instrument room, and the containers, steel cylinders, joints, pipes, gaskets and other connecting parts used to fill the standard gas or carrier gas should be sealed;
b) Before starting the analysis equipment, the standard gas and carrier gas pipelines and equipment should be purged;
c) Before using flammable gases such as hydrogen, the system should be purged with pure nitrogen, and the system can only be put into use after the replacement is qualified.
6.12 Electrical equipment control
6.12.1 Temporary switches, buttons and all electrical equipment should not be randomly connected in flammable and explosive areas.
6.12.2 In the main electrical control room, devices such as operation control, operation indication and fault alarm interlock of the main electrical equipment of the factory (station, workshop) should be installed. The alarm interlock system should be sensitive and reliable.
6. 12.3 If there is an abnormal situation during the starting process of the motor, it should be stopped immediately for inspection, and it should not be started again until the cause is found out and dealt with.
6.12.4 The protection device and protection system of the electric motor should be managed and regularly inspected by special personnel, and the important data of the system should be specially recorded and saved. It is not allowed to change the setting value of the protection device and the important parameters of the protection system at will.
6.12.5 After new installation or overhaul of electrical equipment, before power transmission, tests such as withstand voltage, temperature rise, and insulation protection should be carried out. The control system should carry out circuit test and function test to ensure sensitive and reliable control. After operation, power outage inspection and cleaning should be carried out according to the specified cycle.
6.12.6 All kinds of electrical safety signal devices should be inspected regularly, and the patrol inspection system should be implemented. When sparks and flames are found on the live line, contact the electrician immediately, disconnect the line, and take measures to deal with the fault or put out the fire.
6.12.7 It is forbidden to have sundries and waste oil in cable trenches and wells. It is forbidden to build temporary buildings or warehouses in the cable protection zone, and it is forbidden to pile up bricks and tiles, construction equipment, steel ingots, garbage, acid, alkali and other items harmful to cables, as well as flammable materials.
6.12.8 The shells of electrical equipment and devices and cables with metal shells shall be grounded protectively, and the grounding resistance shall not be greater than 4
7 Related gas production and equipment | Oxygen Compressor Company
7.1 Nitrogen
7.1.1 Oil-free lubrication nitrogen compressor should be selected. The nitrogen compressor should have a complete protection system.
7.1.2 A reliable parking alarm contact signal or parking interlocking device shall be provided between the nitrogen pressure station and the air separation main control room, and a contact system shall be established. 7.1.3 After the nitrogen compressor is running, the nitrogen gas outlet at the back of the machine should be analyzed, and the purity can only be sent into the pipe network. A complete purity monitoring and protection system should be established at the main nitrogen user population.
7.1.4 Nitrogen pipelines and equipment that are newly built and put into production after shutdown for maintenance shall be purged and replaced with nitrogen before they can be put into use.
7.1.5 Nitrogen pipelines should not be laid in traffic trenches.
7.1.6 Where nitrogen is used, the oxygen content in the atmosphere should be monitored regularly, and the oxygen content should not be lower than 19.5%.
7.1.7 Nitrogen should be discharged at high altitude. A warning sign should be hung near the nitrogen discharge port, a warning line should be set up for the pit discharge, and a "no entry" sign should be hung.
7.2 Charm and rare gases
7.2.1 In the gas purification room using hydrogen, its electrical appliances, equipment and devices should meet the explosion-proof requirements of 4.6.
7.2.2 Gas purification equipment and catalytic reactors shall not be added with hydrogen before they are put into production, and only after the oxygen content in the crude gas is less than 3% can hydrogenation be added.
7.2.3 When the temperature of the catalytic reactor is higher than 500 °C, the hydrogenation should be stopped. Before shutting down the chlorine purification equipment, stop adding hydrogen to the crude oxygen and close the hydrogen manual cut-off valve*
The bursting disc of the catalytic reactor shall meet the safety requirements.
7.2.4 Before and after filling the frozen bottle, it should be weighed, and overfilling is strictly prohibited. After filling, the bottle should be reheated and vaporized immediately until it reaches normal temperature. Do not store cryogenic liquids.
When the frozen bottle is gasified, it should be poured with cold water first, and gasified slowly to prevent overpressure.
7.2.5 When replacing nitrogen, the equipment parts of the old system should be strictly degreased.
7.2.6 In atmosphere and gas production, the hydrogen content in crude nitrogen and crude ammonia should not exceed 5%. The amount of oxygen added should be carried out in proportion, and the excess oxygen should be controlled within the range of 0.5% to 1.0%.
7.2.7 In the methane removal system for chlorine and nitrogen production, the temperature of the contact furnace should be kept within the range of 450 °C to 550 °C. The methane content in the chlorine-depleted and protective gas after removing methane should not be higher than 1.0X10-6.
7.2.8 The gas purification room and the rare gas room should have good ventilation facilities.
7.2.9 Gas and rare gas cylinders should be used exclusively for gas, stored in divided areas, and mixed storage and use are strictly prohibited.
7.2.10 Oxygen and rare gases should be analyzed for impurity content with a special gas chromatograph.
7.2.11 The use, storage and transportation of the elements used in the chromatograph should comply with the national regulations on the safety protection of radionuclides.
7.3 Hydrogen (hydrogen production by electrolysis of water inside the oxygen plant) production and equipment
7.3.1 The design of the hydrogen station in the oxygen plant shall comply with the relevant provisions of GB 50177.
7.3.2 The hydrogen station should be equipped with a non-combustible solid wall, and its height should not be less than 2.5 m. The distance between the wall and the station buildings and structures should not be less than 5 months
7.3.3 Fireworks are strictly prohibited in the hydrogen station, and flammable, explosive or oily items are not allowed in the hydrogen production room, and obvious warning signs of "no firework" should be set up around. It is not allowed to wear spiked shoes, chemical fiber or other clothes and hats that generate static electricity to enter the site where hydrogen is produced and used. It is strictly forbidden to use non-explosion-proof communication equipment in the hydrogen station.
7.3.4 The horizontal distance between the lightning rod of the hydrogen station building and the natural exhaust pipe opening shall not be less than 1.5 m, the horizontal distance from the mechanical exhaust pipe opening shall not be less than 3.0 m, and the distance from the discharge pipe shall not be less than 5. 0 m.
The lightning rod should be more than 1.0 m higher than the nozzle within the protection range, the hydrogen pipeline entering and leaving the building should be grounded, and the grounding resistance should meet the requirements of 4.7.1.
7.3.5 All electrical equipment in the hydrogen station shall comply with the relevant provisions of GB 50058 and shall have good insulation protection. Temporary electrical lines should not be hung in the station.
7.3.6 The insulation resistance between the pole pieces in the electrolytic cell should be greater than 1 kΩ; measure the voltage between the electrodes of the electrolytic cell at least once a day, and comply with relevant regulations.
7.3.7 Safety devices such as safety water seals and flame arresters on hydrogen production equipment, pipelines and containers should be intact, sensitive and reliable, and should be checked regularly. Water seals shall be installed at the outlet of the hydrogen scrubber and the inlet and outlet of the wet hydrogen storage tank.
7.3.8 A sensitive and reliable automatic control system shall be adopted to maintain the pressure balance of the hydrogen and oxygen separator and scrubber, and the maximum pressure difference shall not exceed the specified value.
7.3.9 Before starting up the hydrogen production system, use nitrogen to replace the air in the system, and after passing the test, carefully check whether the wiring of the electrodes is correct, and the resistance to ground should be greater than 1 MO.
7.3.10 When the electrolytic cell is running, it is strictly forbidden to directly contact the electrolytic cell or other electrical equipment with tools made of conductive materials. The ground around the electrolytic tank should be laid with insulating rubber sheets.
7.3.11 For the monitoring of important operating parameters, alarm and parking interlock protection devices should be installed. Operators should implement the patrol inspection system and deal with abnormal situations in time.
7. 3. 12 It is advisable to set up online detection devices for hydrogen content in oxygen and oxygen content in hydrogen. When no online detection device is installed, the purity of hydrogen and oxygen should be analyzed every hour to ensure that the purity of hydrogen and oxygen are not less than 99.5%. Effective measures should be taken when the purity of hydrogen is less than 98%. If it is not handled well, it should be stopped immediately, and it can be put into operation after troubleshooting.
7.3.13 The hydrogen pipeline should be laid overhead. Drainage devices should be installed at the low point of the pipeline. A release pipe should be installed at the high point of the pipeline, and a flame arrester should be installed at the nozzle.
7.3.14 It is strictly forbidden for hydrogen pipelines to pass through rooms that do not use hydrogen.
7.3.15 After the hydrogen pipeline is installed, pressure test, air tightness test and leakage test shall be carried out, and the test medium and test pressure shall comply with the relevant provisions of GB 50177.
7.3.16 Hydrogen pipelines that are newly installed or put into production after shutdown for maintenance should be purged before being put into use. Before sending hydrogen, the air in the pipeline and container should be purged with pure nitrogen, and then the nitrogen can be replaced with hydrogen before it can be put into normal production and operation.
7.3.17 There should be a scale at the position of the bell jar of the wet hydrogen storage tank to show the height. It should be checked once an hour, and an over-high and over-low alarm device should be set.
7. 3. 18 The grounding of hydrogen pipelines and storage tanks should be good, and metal wire jumpers should be set at the flange connections, and the jumper resistance should not exceed 0.03. .
7.3.19 Hydrogen cylinders should be painted light green and marked with the word "hydrogen" in red paint. It is strictly forbidden to mix hydrogen cylinders with other gas cylinders, mix them, and mix them, and avoid exposure to the sun and violent collisions. New cylinders should be replaced with nitrogen for air, and then vacuumized or replaced with hydrogen for nitrogen before use.
7.3.20 When hydrogen is used, it is strictly forbidden to mix with air, oxygen and other gases to form explosive gas.
7. 3.21 Instruments, valves and other parts used for hydrogen gas should be well sealed, and should be checked regularly, and any leaks should be dealt with in time.
7.3.22 Concentration alarm devices should be installed in places where hydrogen gas is easy to leak and accumulate indoors.
7.3.23 The hydrogen system should be equipped with a nitrogen replacement purge joint, which is connected to the nitrogen pipeline with a hose when in use, and removed after use.
7.3.24 It is strictly forbidden to use open flames and electric radiators for heating in the hydrogen station.
7.3.25 Copper and copper alloy materials should not be used for valves exposed to hydrogen.
8 Oxygen pipeline
8.1 Pipe layout and safety distance
8.1.1 The oxygen pipeline should be laid on the support of the non-combustible body.
8.1.2 Overhead oxygen pipelines shall be equipped with lightning protection and anti-static grounding measures at the bifurcation of the pipeline, the intersection with the power overhead cable, every 80 m~100 m of the non-branch pipeline, and the entry and exit devices or facilities.
8.1.3 After the oxygen plant (station, workshop) boundary valve, the oxygen main pipe is sent to a system branch pipe valve, after the valve entering the workshop, before the control valve group and before and after the control valve, the oxygen pipeline should be equipped with fire-resistant copper pipes part.
When the oxygen regulating valve group is equipped with an independent valve room or a protective wall, the valve stem of the manual valve should be extended outside the protective wall for operation. If the valve room or protective wall is not set separately, within the range of 8 times the nominal diameter of the regulating valve before and after the oxygen regulating valve, copper alloy (except copper alloy containing aluminum) or iron-based alloy pipes shall be used.
8.1.4 Oxygen pipelines are strictly forbidden to pass through living rooms and offices, and should not pass through rooms that do not use oxygen. If it is necessary to pass through, measures such as preventing oxygen leakage should be taken in the room.
8.1.5 Oxygen pipelines should not pass through high temperature and flame areas. If they must pass through, heat insulation facilities should be added to the pipeline section, and the temperature of the pipe wall should not exceed 70 °C. It is strictly forbidden to keep open flames and oil stains close to oxygen pipes and valves.
8.1.6 The elbow and tee of the oxygen pipeline should not be directly connected to the valve outlet. For regulating valve groups, main pipe valves, branch pipe valves for a system, and workshop inlet valves, the pipes on the outlet side should have a straight pipe section with a length not less than 5 times the nominal diameter of the pipe and not less than 1.5 m.
8.1.7 When the oxygen branch pipe for cutting and welding is connected with the hose for cutting and welding tools or equipment, the oxygen supply valve and shut-off valve should be installed in a protective box made of non-combustible materials.
8.1.8 Oxygen pipelines should be laid overhead. Oxygen pipelines can be laid along building components that produce or use oxygen. There should be no buildings under the flanges, threads, valves and other places prone to leakage of overhead oxygen pipelines in the factory building.
8.1.9 The minimum spacing requirements between overhead oxygen pipelines and specific locations of buildings and structures shall be implemented in accordance with Table 6.
Table 6 The minimum clear distance between overhead oxygen pipelines, pipe racks and buildings, structures, railways, roads, etc., in meters

Name Minimum Horizontal Clearance Minimum vertical clearance
The outside of a wall or protrusion of a building with doors and windows 3.0
The outside of a wall or protrusion of a building with doors and windows 1.5
Non-electrified railway rails 3.0 5. 5
Electrified Railway Rails 3.0 6.6
the way 1.0 5.0
sidewalk 0. 5 2.5
Factory fence (central line) 1.0
Lighting, telecommunications pole center 1.0
Molten metal locations and open flame locations 10.0
Note 1: The minimum horizontal clear distance in the table: pipes are calculated from the outer wall; urban roads are calculated from the edge of the road surface; highways are calculated from the edge of the shoulder; railways are calculated from the outside of the track or according to the building boundary; sidewalks are calculated from the outer edge.
Note 2: The minimum vertical clearance in the table: pipes are counted from the outer edge of protective facilities; pipe racks are counted from the lowest part; railways are counted from the track surface; roads are counted from the road crown; sidewalks are counted from the road surface.
Note 3: When there is a large-scale transportation requirement or a road with large-scale lifting facilities passing through during maintenance, the minimum vertical clearance should be determined according to the needs.
Note 4: The provisions of the minimum horizontal clear distance from the building in the table are not applicable to the pipelines laid along the outer wall of the oxygen production workshop or oxygen user workshop
Table 6 The minimum clear distance between overhead oxygen pipelines, pipe racks and buildings, structures, railways, roads, etc., in meters
1.10 The minimum distance between the overhead oxygen pipeline and other pipelines shall be in accordance with Table 7.
Table 7 Minimum clear distance between overhead oxygen pipelines and other overhead pipelines in meters
Name Minimum parallel clearance Minimum cross clearance
water supply pipe, drain pipe Meet maintenance requirements 0. 10
steam pipe 0.25 0. 10
non-combustible gas pipe Meet maintenance requirements 0. 10
Gas pipe, fuel pipe 0.50 0.25
Open trolley line for cranes 1. 50 0.50
Insulated cables up to 10 kV 1. 00 0. 50
10 kV and below insulated cables with sleeves 0. 50 0. 50
Plug-in busbar, suspended trunk 1. 50 0.50
Non-explosion-proof switches, sockets, distribution boxes 1. 50 1. 50
With overhead bare cables:
66kV~35kV
Highest pole (tower) height 4.0
10 kV3 kV Highest pole (tower) height 3.0
Below 3 kV Highest pole (tower) height 1.5
Note 1: When the oxygen pipeline and the gas pipeline are laid in parallel, when the pipeline adopts a welded connection structure and no valve, the minimum parallel spacing can be reduced to 0.25 m0
Note 2: The valves and fittings joints of oxygen pipelines and the valves and fittings joints of gas and fuel oil pipelines should be staggered by a certain distance along the pipeline axis; distance.
Note 3: If the electrical equipment and the oxygen outlet cannot meet the above distance requirements, they can be installed on the opposite side of the same column; when the column is empty, a non-combustible partition should be installed on the column to partially separate them.
Note 4: The clear distance from the trolley line refers to the requirement when the oxygen pipeline is below it. At this time, an isolation net should be set between the oxygen pipeline and the trolley line.
Note 5: In areas where paths are restricted, the minimum parallel clear distance between overhead oxygen pipelines and overhead bare cables of 10 kV and below can be implemented with reference to DL/T 5220.
8.1.11 When the oxygen pipeline is laid together with the ethane and hydrogen pipelines, it should be placed under the ethane and hydrogen pipelines or on both sides of the support; above or on both sides of the bracket.
8.1.12 When the oxygen pipeline is laid in the impassable trench, it shall meet the following requirements:
a) A cover plate shall be installed on the ditch to prevent the intrusion of combustible materials and sparks. The ditch and the cover plate shall be made of non-combustible materials; the ditch shall be able to drain stagnant water; it is strictly forbidden for grease and combustibles to leak into the ditch;
b) Oxygen pipelines in the trench should not be provided with valves, flanges, threads and other leak-prone interfaces;
c) Refer to Table 7 for the distance between the oxygen pipeline in the trench and the pipeline laid in the same trench;
d) When the oxygen pipeline in the trench is laid in the same ditch as the non-gas and water pipelines, the oxygen pipeline should be on top;
e) It is strictly forbidden to lay oxygen pipelines in the same ditch as combustible gas pipelines (excluding ethane gas), oily pipelines, corrosive medium pipelines, and cables; and it is strictly forbidden for oxygen pipeline trenches to communicate with such pipeline trenches.
8.1.13 Oxygen pipelines in the factory building should not be laid underground.
8.1.14 Oxygen pipelines are difficult to be overhead and must be laid underground, and the following requirements shall be met:
a) The buried depth shall be determined according to the load on the ground. Buried oxygen pipelines should be laid below the permafrost layer. When crossing railways and roads, the intersection angle should not be less than 45°, and casings should be installed. The distance between the casing top and the bottom surface of the rail should not be less than 1.2 m, and the distance from the road surface should not be less than 0.7 m;
b) For directly buried pipelines, corresponding levels of anti-corrosion measures should be taken according to the corrosion level of the soil in the buried area;
c) It is not advisable to install valves or flange connection points on buried pipelines, and valve wells should be installed when they must be installed;

d) The minimum clear distance between buried oxygen pipelines and buildings, pipelines and other buried pipelines shall be implemented in accordance with Table 8, and shall not be buried under open storage yards or pass through flues and trenches.
Table 8 The minimum clear distance between underground oxygen pipelines and buildings, structures, etc., and other underground pipelines, in meters
Name Minimum Horizontal Clearance Minimum vertical clearance
The building foundation with basement or the outer edge of the access channel Oxygen pressure<1.6 MPa Oxygen pressure> 1.6 MPa 3.0
5.0
Outer edge of building foundation without basement Oxygen pressure<1.6MPa Oxygen pressure>1.6 MPa 2.5
3.0
railway rails 2. 5 (outside of rail) 1. 20
Outer edge of the gutter 0.8
the way 0.8 0.7
lighting utility pole 0.8
Electricity (220 V, 380 V), telecommunications poles 1.5
High-voltage power (above 1 000 V) poles 2.0
Outer edge of pipe frame foundation 0.8
outer edge of fence foundation 1.0
Arbor Center 1.5
shrub center 1.0
Water pipe
Diameter V75 mm
Diameter 75 mm ~ 150 mm
Diameter 200mm~400mm
Diameter > 400mm
0. 8
1.0
1.2
1.5
0. 15
0. 15
0. 15
0. 15
drain pipe
Diameter V800mm
Diameter 800 mm ~ 1 500 mm
Diameter > 1 500 mm
0. 8
1.0
1.2
0. 15
0. 15
0. 15
Heat pipe or the outer edge of impassable trench 1.5 0.25
Gas pipe (Yihuan, etc.) 1.5 0. 25
gas pipe
Gas pressure <0. 005 MPa
Gas pressure > 0. 005 MPa ~ 0. 15 MPa
1.0
1.2
0. 25
0.25
Gas pressure > 0. 15 MPa ~ 0. 3 MPa
Gas pressure>0. 3 MPa
1.5
2.0
0. 25
0.25
Non-combustible gas pipes (compressed air, etc.) 1.5 0. 15
Table 8 (continued) in meters
Name Minimum Horizontal Clearance Minimum vertical clearance
power cable
Voltage VI kv
Voltage 1 kV ~ 10 kV
Voltage>10kV~35kV
0.8
0.8
1.0
0. 50
0. 50
0. 50
Telecommunications Cables Direct Buried Cables
cable duct
0.8
1.0
0. 50
0. 15
cable trench 1.5 0.25
Note 1: When oxygen is laid at the same level as refining and gas pipelines for the same purpose, the minimum clear distance between pipelines can be reduced to 0.25 m, but within the range from the bottom of the ditch to the height of 300 mm above the top of the pipe, loose Backfill with soil or sand.
Note 2: When the oxygen pipeline crosses the cables passing through the pipeline, the minimum crossing clear distance can be reduced to 0.25 mo
Note 3: The provisions of the minimum horizontal clear distance of the building foundation in this table refer to the minimum horizontal clear distance between the buried pipeline and the foundation at the same level or on the outside.
Note 4: For pipe sections laid under railways and roads that are inconvenient to excavate, sleeves should be added. The pipe section inside the 1mo casing extending out of the ditch edge should minimize welds.
Note 5: The minimum horizontal clear distance in the table: the pipelines are calculated from the outer edge of the pipe wall, ditch wall or protective facility or the outermost cable. When the road is urban, it is from the edge of the road surface; when it is a highway, it is from the road shoulder. Counting from the edge, the railway is counted from the outside of the track.
Note 6: The regulations on the minimum vertical clear distance of pipes, cables and cable trenches in the table refer to the net distance between the outer top of the lower pipe or trench and the bottom of the upper pipe or foundation bottom of the trench. The regulations on the vertical clear distance between railway rails and roads, railways are calculated from the bottom of the rail to the top of the pipe; roads are calculated from the bottom of the pavement structure layer to the top of the pipe.
8.2 Oxygen flow rate
The maximum allowable flow rate of oxygen in the pipeline should not exceed the provisions in Table 9 according to the pipeline material and working pressure. Table 9 The maximum permissible flow of oxygen in the pipeline
material Working pressure p/MPa
/><0. 1 0. 1V》<1. 0 1.0<p<3. 0 3. 0</><10.0 10. 0<p<15. 0 15. 0
carbon steel According to the pressure drop of the piping system 20 m/s 15 m/ s not allowed not allowed not allowed
Austenitic
Stainless steel
30 m/s 25 m/s 77^45 MPa • m/s (in case of impact)
MPa • m/s (non-impact occasions)
4. 5 m/s (in case of impact)
8. 0 m/s (non-impact)
4. 5 m/s
Note 1: The maximum allowable flow rate refers to the actual flow rate at the minimum working pressure and maximum working temperature of the piping system.
Note 2: Impact occasions and non-impact occasions: the position where the fluid flow direction changes suddenly or a vortex is generated, thereby causing the particles in the fluid to impact on the pipe wall. Such a position is called an impact occasion; otherwise it is called a non-impact occasion.
Note 3: For copper and copper alloys (except aluminum-copper alloys), iron and iron-copper alloys, under the condition of less than or equal to 21.0 MPa, the flow rate is not limited when the pressure drop allows.
Oxygen Compressor Company will introduce you more deep cooling method to produce oxygen and related gas safety technical regulations.