1. LNG is being first time introduced in India for domestic / small non-domestic consumers by supply in containers.
Since LNG is a non-toxic, flammable cryogenic liquefied gas, it is essential to comply with strict safety and fire procedures and practice in its storage, filling and transportation operations. At present, there are no national standards for LNG containers filling and distribution. The LNG distribution in containers is first time in India. So, M/S JEL shall follow international standards for the same.
Hence, Jindal Energy Limited (JEL) has decided to implement its LNG hub pilot plant project by following prevailing standards, codes, procedures in construction, design, storage, cylinder filling and operation in USA and European Countries.
2. JEL is committed to follow and maintain highest level safety standards during various stages of project, commissioning and operation and distribution of material. Hence JEL has conducted various safety studies through renowned consultants and submitted the reports to PESO as supporting documents to the approval application for project implementation.
The various technical reports prepared are as follows:
HAZOP Study Report
Quantitative Risk Assessment
Standard Operating Procedure
Fire Protection System
3. The procedures of procurement of cryogenic containers for filling LNG shall also be followed as per guidelines of PESO. The containers shall be procured / imported from the world renowned suppliers such as CHART, TAYLOR WHARTON, TGL, CRYOLAR, INOX etc. Only after prior approval of PESO.
6.10.1 IMPORTANT SAFETY FEATURES OF PLANT
Safety in our LNG plant shall be insured by four elements that provide multiple layers of protection both for the safety of plant workers and safety of communities that surrounds LNG facilities.
1. Storage of LNG: It is the first and most important requirement for containing the LNG product. The LNG storage tank shall be full containment container in which inner vessel is self-standing having material of construction S.S. 316 and surrounded by a separate self- standing secondary container of carbon steel designed to contain LNG in the event of spill from the inner primary container. Since this is a multi-layer tank, no leakage is envisaged and system may be considered full- proof.
2. Safeguard systems offers a third layer of protection: The objective is to prevent / minimize the frequency and size of LNG release and prevent having from potential associated hazards such as fire. To provide this level of safety protection, LNG operations use technologies like high level instrumentation with alarms, and multiple back up safety systems which include emergency shutdown systems (ESD). ESD systems can identify problems and shut off operations in the events of certain specified faulty conditions or equipment failure occurs and which are designed to prevent a limit the significantly the amount of LNG and LNG vapors that could be released. Fire and gas detectors and firefighting systems all combine to limit effects if there is a release.
3. The LNG facility in charge should take action by establishing necessary operating procedures, training, emergency response systems and regular preventive maintenance to protect people, property and environment from any release.
4. Finally, LNG facility shall be designed as required by regulations to maintain separation distances between the equipment’s, provisions of roads for vehicle movements, provision of
emergency escapes, ventilation at filing and storage areas, minimum distance between periphery of equipment’s and boundary of premises, etc.
6.10.2 SAFETY IN LNG CONTAINERS
LNG container is a double layer vessel. They are designed with International standards of pressure vessel with appropriate material of construction. The inner and outer vessels are constructed of SS 304. Inner vessel support system, foot ring and the works protective ring designed to withstand many years of service in Industrial, chemical and medical applications.
The salient features of design are as follows:
i) The insulation system is provided by multilayer spiral wrapped insulation of the inner vessel, a high vacuum between the vessels, and an inner vessel support system which is a designed to minimize next communication between the vessels while providing safe support during handling.
ii) The cylinder has 2 safety relief devices to protect the inner vessel and 2 safety devices to protect outer vessel from over pressurization.
iii) Pressure Building System: An internal automatically controlled pressure building system is provided with these cylinders to maintain the desired gas pressure wile continuous gas withdrawal is taking place. This system is automatically controlled by the pressure building / economizer regulatory, but can be insulated by actuating the pressure building valve directly behind the regulator. Gas withdrawal is accomplished through an internal vaporizer that will provide continuous flow rates. If higher flow rates are needed, external vaporizers can be added.
6.10.3 CONTAINERS TRANSPORTATION
Cryogenic Liquid Cylinders are portable cryogenic pressure vessels, tested, rated and approved over the road transportation under US DOT 4L specifications.
When transporting it, the following suggestions complied with:
1. Safety precautions in loading and unloading shall be taken.
2. Do not roll the cryogenic containers by the handling ring as by holding the liquid level indicator is plastic protective cover.
3. Container should be stored and operated under vertical condition.
4. Never lay, store or ship a container on the side.
5. After loading, heavy duty nylon straps should be used to fix the containers securely in a truck.