774c66533fc4f230c1c4cc4b69c46d6d.ppt
- Количество слайдов: 16
ISSHR 2015 - Bio-data of speaker Name: VIJAY KUMAR Designation: Jt. General Manager (FS&PD) Organisation: MECON LIMITED Work Experience: 32 years of experience in Design & engineering of Gas pipelines, Gas cleaning Plants & other gas related facilities Awards/ Achievements: Papers published/ presented: Certificate from MECON, CMD for excellence in the field of knowledge sharing in BOF gas cleaning plant Paper on disaster management presented in Institution of engineers MECON LIMITED A House of Engineering Excellence
WELCOME TO PRESENTATION ON GAS SAFETY IN STEEL PLANT BY VIJAY KUMAR Jt. General Manager, FS&PD MECON LIMITED A House of Engineering Excellence
WHY SAFETY CHECKS BEFORE CHARGING OF GAS NETWORK? IN STEEL ARE 1. 2. 3. 4. PLANTS INHOUSE GENERATED FUEL GASES BF GAS LD GAS (BOF GAS) COKE-OVEN GAS MIXTURE OF ABOVE GASES • THE ABOVE GASES ARE HIGHLY HAZARDOUS AND TOXIC IN NATURE. • THIS REQUIRES STRINGENT SAFETY BEFORE CHARGING TO ENSURE SAFE & RELIABLE OPERATION. MECON LIMITED A House of Engineering Excellence
CHARACTERISTIC OF BLAST FURNACE GAS (BF GAS) Typical composition: Constituent % by Volume Carbon Monoxide (CO) 22. 2 Carbon dioxide (CO 2) 19. 2 Hydrogen (H 2) 4. 0 Nitrogen (N 2) 54. 4 Oxygen (O 2) 0. 2 Properties: Gross calorific value 10 -15 g/Nm 3 Dust Content (After GCP) 5 mg/Nm 3 Water vapour 0. 5 gm/Nm 3 Density 1550 -1600 Nm 3/t of hot metal (1. 32 G. cal/t of hot metal) 750 -850 Kcal/Nm 3 Dust Content (Before GCP) BF GAS GENARATION RATE FROM BF 1. 33 to 1. 35 kg/Nm 3 MECON LIMITED A House of Engineering Excellence
CHARACTERISTIC OF BASIC OXYGEN FURNACE GAS (BOF GAS) Typical composition: Constituent % by Volume Carbon Monoxide (CO) 65 Carbon dioxide (CO 2) 17. 8 Hydrogen (H 2) 1. 5 Nitrogen (N 2) 15. 5 Oxygen (O 2) 0. 2 Properties: Gross calorific value 2000 Kcal/Nm 3 Dust Content (Before Scrubber) 150 -230 g/Nm 3 Dust Content (After Scrubber) 50 mg/Nm 3 Dust Content (After ESP) 5 mg/Nm 3 Density 1. 33 to 1. 35 kg/Nm 3 RECOVERABLE BOF GAS GENARATION RATE 80 Nm 3/t of hot metal (0. 16 G. cal/t of hot metal) GAS GENERATION AT CONVERTER MOUTH 1. 8 to 1. 9 X O 2 blowing rate MECON LIMITED A House of Engineering Excellence
CHARACTERISTIC OF COKE OVEN GAS (CO GAS) Typical composition: Constituent % by Volume Carbon Monoxide (CO) 7. 1 Carbon dioxide (CO 2) 2. 4 Hydrogen (H 2) 58. 4 Nitrogen (N 2) 3. 6 Oxygen (O 2) 0. 4 Methane (CH 4) 25. 7 Ethane (C 2 H 6) 2. 4 COKE OVEN GAS GENARATION RATE 310 -320 Nm 3/t of dry coal charge (1. 32 G. cal/t of dry coal charge) Properties: Gross calorific value 4000 -4200 Kcal/Nm 3 Tar fog 0. 005 gm/Nm 3 Density 0. 45 -0. 47 kg/Nm 3 Hydrogen Sulphide 3. 40 gm/Nm 3 Ammonia 48. 0 mg/Nm 3 Naphthalene 92. 0 mg/Nm 3 MECON LIMITED A House of Engineering Excellence
PHYSIOLOGICAL EFFECTS OF CO ON HUMAN BODY Poisoning effect of CO is based on the fact that it combines easily with the haemoglobin of the blood forming carboxy-hemoglobin. The affinity of “CO” for haemoglobin is 300 times that of oxygen. When oxygen is replaced by “CO” in the haemoglobin of the blood capacity of hemoglobin carrying O 2 to the tissues cannot function properly because of oxygen hunger and more accumulation of CO in the haemoglobin of blood at a certain stage stops the function of body. The symptoms of CO poisoning are headache, weakness, dizziness, vomiting, fainting, collapse, coma, respiratory failure and death. MECON LIMITED A House of Engineering Excellence
EFFECT OF CO ON HUMAN BEING CO CONTENT IN PPM 50 EFFECTS ON HUMAN BEING None (Maximum level of exposure for 8 hours working per day) 100 Tightness across forehead, headache within 1 -2 hours 200 Severe headache, throbbing sensation in the head, dizziness caused within 1 – 2 hours Severe headache, weakness, shortness of breath, dizziness, dimness of vision within 1 -2 hours Unconsciousness, depressed heart action and respiration, death is possible within 2 hours Weak pulse and slower respiration, respiratory failure and death within 2 hours Headache, dizziness and nausea in 20 minutes, collapse, unconsciousness, possibly death in 2 hours Headache, dizziness in 1 - 2 minutes, unconsciousness and danger of death in 10 – 15 minutes Immediate effect, unconsciousness and danger of death in 1 -3 minutes 600 800 1000 1600 6400 12800 MECON LIMITED A House of Engineering Excellence
SAFETY CHECKS REQUIRED BEFORE CHARGING • CHECKING OF PURGE POINT WITH CONNECTION DETAILS • VENT ASSEMBLY OF ADEQUATE HEIGHT WITH SAMPLING POINTS • GAS CONDENSATE DRAINS USING SEAL POTS • POSITIVE ISOLATION SYSTEM (U-SEAL) • ISOLATION VALVES • APPROACH LADDERS/STAIRCASES FOR MAINTENACE PURPOSE • PLATFORMS, CROSS OVERS AND WALKWAYS WITH HAND RAILS & TOE GUARDS MECON LIMITED A House of Engineering Excellence
SAFETY CHECKS continued…. • MEDIA PIPES FOR ISOLATION AND PURGING NEEDS • LAYING OF FUEL GAS PIPES WITH OTHER PIPES CAUSING HAZARD • CONNECTIONS OF HOSES • NRV AT T. O. P. OF EACH SHOP FOR PIPES HAVING INTERFACING WITH FUEL GAS PIPES • GAS DETECTION AND ALARM SYSTEM & AVAILABILITY OF PORTABLE CO MONITORS • HAZOP STUDY MECON LIMITED A House of Engineering Excellence
SAFETY CHECKS continued…. • VISUAL INSPECTION • RE-TESTING OF PIPELINES FOR LEAKAGES • PROPER DRAINAGE OF DRAINS FROM GAS LINES • VALVE REVISIONING & HOLDING TEST • EXPANSION JOINTS • CHECKING OF SUPPORT TYPE AND ITS WELDING • HEAT PROTECTION SHEILDS MECON LIMITED A House of Engineering Excellence
SAFETY CHECKS continued…. • FAIL SAFE POSITIONS OF CONTROL VALVES • DEDICATED VESSELS FOR UNINTERUPPED AIR SUPPLY TO VALVES & INSTRUMENTS • SAFETY POSTERS MECON LIMITED A House of Engineering Excellence
WHAT IS HAZOP STUDY? • HAZOP is a very useful technique for hazard evaluation. • The basic assumption in HAZOP is that the process will work well safely as long as it is operating under design conditions. • The objective is to identify the problems which might arise when deviations from design conditions occur. • HAZOP is also called “what if” method. • HAZOP study highlights the hidden operability problems and identifies hazards. • HAZOP is a brainstorming approach which stimulates Creativity and procedure for generating ideas. • HAZOP study is generally undertaken for units involving process controls and not applicable to units where the process and operations are mechanical in nature. MECON LIMITED A House of Engineering Excellence
IMPORTANT TERMS & GUIDE WORDS USED IN HAZOP STUDY Guide Words None / No More Less Meaning No Action Comments No part of the intention is achieved; e. g. No flow, No Pressure. Quantitative More of any relevant physical property Increase than there should be; e. g. higher flow, higher temperature, higher pressure, more heat, etc. Quantitative Less of any relevant physical properly Decrease than there should be; e. g. lower flow, lower pressure, less heat etc. IMPORTANT TERMS Intention Deviation Causes Hazards Consequences MECON LIMITED A House of Engineering Excellence
HAZARD & ITS ANALYSIS • • Hazard is a physical situation, which may cause human injury, damage to property or the environment or some combination of these. The hazard may be created by a chemical and is indicated by fire, explosion, toxicity, corrosiveness etc. The potential of different chemicals to create hazard varies. Type of HAZARD are as follows; 1. Flammable substance 2. Oxidising substance, reacts with reducing agents. 3. Emits a toxic gas or vapour 4. Emits an irritating gas or vapour 5. Emits a narcotic gas or vapour 6. Gas or vapour not dangerous other than displacing air 7. Causes skin irritation or burns 8. Toxic substance 9. Explosive material under certain condition MECON LIMITED A House of Engineering Excellence
THANK YOU MECON LIMITED A House of Engineering Excellence
774c66533fc4f230c1c4cc4b69c46d6d.ppt