Ecce 1106-013-environmental-risk-compliance-for-nature-gas


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Ecce 1106-013-environmental-risk-compliance-for-nature-gas

  1. 1. Canadian Journal on Environmental, Construction and Civil Engineering Vol. 2, No. 5, June 2011 Environmental Risk Compliance for Nature Gas Ship Design and Operation O.O. Sulaiman, A.H. Saharuddin, A.S.A. Kader, W.B.Wan NikAbstract — The quests for an efficient fuel friendly to the The drive towards environmentally friendlier fuels points nextenvironment have been recognized in maritime industry for a to Natural Gas (NG) and the infrastructures to support thatlong time through improvements of gasoline and diesel by trend are being pre-positioned by corporate mechanisms aschemical reformulation. Inconvenience posed by these well as governmental bodies worldwide. NG is cheap and itsreformulation chemicals is performance problems; cold-start reserve is plentiful. Natural Gas as fuel is becoming more andability, smooth operation and avoidance of vapor lock. more established in urban transport and Power GenerationClimate change problem has further aggravated need to use sectors. Its use will also take aggressive approach for all inlandfuel that could contribute to decrease in green house gases vessel including ferries in the eyes of potential environmentaland ozone-forming pollutants. Alternative fuels to petroleum compliance new regulations. Internationally its operationalhave been identified to include, compressed natural gas record and GHG gas score is rated as GOOD. However, CNG,(CNG); liquefied petroleum gas (LPG); methanol from natural LPG and ethanol has been proven to be environmental friendlygas LNG. Selection of this towards centralized reduction of and has fuel economy of 50 percent. This shows that, CNGGreen House Gases (GHGs) will depend on ease of use, and LPG have potential for large market for use in nicheperformance and cost. LNG cargo is conditioned for long markets in both developed and developing countries. Otherdistance transfer while CNG and LPG cargo are conditioned gains from CNG and LPG depend on the amount of associatedfor end user consumption and short distance transfer. It is methane emissions from gas recovery, transmission,therefore, clear that promoting the use of CNG will catalyze distribution, and use. On a full-cycle basis, use of LPG canboosting of economy of coastal ship building and result in 20-25% reduction in GHG emissions as compared totransportation, including environmental friendly utility fuel, petrol, while emission benefits from CNG are smaller - aboutand new generation of intermodal transportation and supply 15%. [1]chain. Since the danger behind use of this gas could not beeither underestimated by virtue regarding coastal operation Furthermore, it is clear that promoting the use of CNG andproximity and consequence. The paper will discuss risk and LPG will be a catalyst to boost economy of coastal shippotential regulation that will formulate beyond compliance, building, environmental friendly intermodal transportation fordecision towards use of top - down risk based design and supply chain.. Efficient and reliable operation can be madeoperations that will reinforce new integrative, efficient, afforded by LPG, transportation, supply vessel, tugs to supportenvironmental friendly, reliable multimodal and intermodal this potential development. On the regulatory regime, IMOlinks advanced concepts for LPG ship operating in coastal focus more on operational issues relating to carriage of gasand restricted waters. with no specification for CNG and LPG, while the ICG code and class society guidelines elaborate on the design as well as operational consideration. Local administration imposesKey Words — NG, LNG, CNG, LPG, HAZOP, penilaian additional regulation as required for their respectiverisiko, Terusan, Rekaan berdasarkan Risiko dan implementation.matlamat, Persekitaran, Tenaga Time has revealed that there will be large demands for these I. INTRODUCTION gases. This paper focus on integrative use of IMO prescriptive goal and risk based standards with holistic consideration of Fuel technology has been dominated with ways to improve factors require for safe design and operation of LPG ships ingasoline and diesel by chemical reformulation that can lead inland water. Including hybrid use of elements of Formalincrease efficiency and additional inconvenience leading to Safety Assessment (FSA) and Goal Based Standards (GBS) toozone depletion, green house and acid rain forming pollutants. prevent, minimize control and guarantee the life span of LPGLikewise, side effects problems posed to transportation ships and protection of environment. The paper will discussedvehicles have been dominated by condition, other performance top down environmental risk generic risk model andissues. Time has shown that the global trend in de- operations of LPG ship. It will describe the characteristics ofCarbonization of the energy system follow the following path: LPG, regulatory issues and environmental issues drivingCOAL > OIL> NATURAL GAS > HYDROGEN today’s beyond compliance and selection of new technology 56
  2. 2. Canadian Journal on Environmental, Construction and Civil Engineering Vol. 2, No. 5, June 2011policy. Since it is the consequence of accident and incident A. Transportation of Gas - The best place to install the plant isthat leads to environment disaster, the paper will discussed near the gas source. The gas is basically transported throughissues that allow prevention and control of accident. Since pipelines or by truck and barge.issues relating to global warming, GHG releases is strictlylinked to ship energy source, the paper will also discuss impact B. Pretreatment of Gas- The liquefaction process requires thatareas and potential new technology driving beyond compliance all components that solidify at liquefaction temperatures mustpolicy adoption for LPG design and operation. be removed prior to liquefaction. This step refers of treatment the gas requires to make it liquefiable including compression, O.O. Sulaiman is with the University Malaysia Terengganu, Faculty filtering of solids, removal of liquids and gases that would of Maritime Studies and Marine Science, 21030, Kuala solidify under liquefaction, and purification which is removal Terengganu,Terengganu, Malaysia (e-mail: A.H. Saharuddin is with the University Malaysia Terengganu, of non-methane gases. Faculty of Maritime Studies and Marine Science, 21030, Kuala Terengganu,Terengganu, Malaysia (e-mail: C. Liquefaction of Gas - Today, alternative fuels to petroleum W.B. Wan Nik is with the University Malaysia Terengganu, Faculty has been identified to include Compressed Natural Gas of Maritime Studies and Marine Science, 21030, Kuala (CNG); Liquefied Petroleum Gas (LPG); methanol from Terengganu,Terengganu, Malaysia (e-mail: A.S.A Kader is with the University Technology Malaysia, Faculty of natural gas, coal or biomass; ethanol from biomass; electricity Mechanicak Engineering, Johor Bahru, Skudai, Malaysia (e-mail: and hydrogen. However NG quality may be expressed with the Wobbe Index - Methane Number MN80 (Volume percent hydrogen atoms / carbon atoms) or Methane >=88% Since 1960s, CNG and LPG are recognized as vehicle fuel II. NATURAL GAS AND ITS PRODUCTS alternative to oil-based gasoline and diesel fuel that reduces pollution of the air. It is a natural gas compressed to a volume Natural gas in its liquid state (LNG) or liquid natural gas and density that is practical as a portable fuel supply.that comprise of liquid hydrocarbons that are recovered from Compressed natural gas (CNG) and Liquefies petroleum gasnatural gases in gas processing plants, and in some cases, from (LPG) are use as consumer fuel for vehicles, cooking food andfield processing facilities. These hydrocarbons involve heat homes. There exist a vast number of natural gaspropane, pentanes, ethane, butane and some other heavy liquefaction plants designs, but, all are based on theelements. LNG accounts for about 4% of natural gas combination of heat exchanger and refrigeration. The gasconsumption worldwide, and is produced in dozens of large- being liquefied, however, takes the same liquefaction path.scale liquefaction plants. Natural gas contains less carbon than The dry, clean gas enters a heat exchanger and exits as LNG.any other fossil fuel and, therefore produces less carbon The capital invested in a plant and the operating cost of anyDioxide (CO2) when compared to any conventional vehicles. liquefaction plant is based on the refrigeration techniques.Its usage also results in significantly less carbon monoxide(CO), as well as less combustive organic compounds than their Natural gas is transported through pipelines to refuellinggasoline counterparts. It is produced by cooling natural gas to stations then compressed at a pressure of 3,000 psi with thea temperature of minus 260 degrees F (minus 160 Celsius). At help of specially installed compressors that enables it to bethis temperature, natural gas becomes liquid and its volume loaded as gas cylinders for vehicles.reduces 615 times. LNG has high energy density, which makes The process consists of drawing the natural gas fromit useful for energy storage in double-walled, vacuum-insulated underground pipelines by the compressor. The composition oftanks as well as transoceanic transportation. pipeline natural gas varies considerably depending on the time of year, pipeline demand, and pipeline system. It may contain The production process of LNG starts with Natural Gas, impurities, like oil, particulates, hydrogen sulphide, oxygen orbeing transported to the LNG Plant site as feedstock, after water. Hence, the modern day, quality LPG plant systemfiltration and metering in the feedstock reception facility, the consists of facilities to address these problems. Using LNG asfeedstock gas enters the LNG plant and is distributed among the feedstock to make CNG and LPG eliminates or mitigatesthe identical liquefaction systems. Each LNG process plant each of the above stated concerns as contains no water or anyconsists of reception, acid gas removal, dehydration removal, such impurity. This eliminates the concerns for corrosion,mercury removal, gas chilling and liquefaction, refrigeration, plugging of fuel lines, and the formation of hydrates.fractionation, nitrogen rejection and sulfur recovery units. LPG Significant design innovation will involve developmentand CNG are made by compressing purified natural gas, then of liquefied gas technology that promises lower costs andstored and distributed in hard containers. Mostly, LPG station shorter scheduling time than either Liquefied Natural Gasis created by connecting a fuel compressor to the nearest technology or a pipeline transport as well as provision ofnatural gas pipeline distribution system. The process through unique solution to the development of distressed or strandedwhich Liquefied Natural Gas is produced consists of tree main gas reserves and alternative to associated gas re-injection.steps, namely:- Liquefied Petroleum Gas (LPG) can also be produced either as a by-product when refining crude oil or direct from the gas 57
  3. 3. Canadian Journal on Environmental, Construction and Civil Engineering Vol. 2, No. 5, June 2011wells. The two most common LPG gases are known as 42.4% of the density of air and thus is lighter and mayCommercial Propane and Commercial Butane as defined in BS disappear in case of leakages.4250 [2] Up to 15kg and generally used for leisure applications and IV. 4. NATURAL GAS AND LPGmobile heaters. Commercial Propane is predominately storedin red cylinders and bulk storage vessels and especially used LG carriers has proven considerable good safe ship in termfor heating, cooking and numerous commercial and industrial of designed, constructed, maintained, manned and operated ofapplications. LPG has one key characteristic that distinguishes all the merchant fleet of today. So far they have low accidentit from Natural Gas. Under modest pressure LPG gas vapor record and non major has lead to release of large amounts ofbecomes a liquid. This makes it easy to be stored and LG have ever occurred in the history of LG shipping.transported in specially constructed vessels and cylinders. The Nevertheless, there have been major concerns regarding safetycombustion of LPG produces Carbon Dioxide (CO2) and water of LG shipping and vivid that one catastrophic accident has thevapor therefore sufficient air must be available for appliances potential for serious consequential fatal and environmentalto burn efficiently. Inadequate appliance and ventilation can damage. Therefore it became imperative to use IMO Goal -result in the production of toxic Carbon Monoxide (CO). All based and risk based instruments to quantify a baseline riskthings being equal, it produces much less hydrocarbon level to identify and evaluate alternative risk control optionscompare to diesel. Hazards associated with LPG ships are for improved safety. Toward zero accident and zero, incident,linked to the gas characteristics that attract beyond apart from normal SOLAS standards for all ships, there arecompliances operability and design policy. Selection of this additional international regulation / Code for the Constructiontowards centralized reduction of GHGs will depend on ease of and Equipment of Ships Carrying Liquefied Gases in Bulk thisuse, performance and cost. include- The IGC Code. This Code is applicable to Liquefy gas carriers which are made mandatory under the SOLAS III. . NATURAL GAS PROPERTIES Convention. Thus, Risks associated with LPG ships encompass the following Everyone dealing with the storage and handling of LPG areas:should be familiar with the key characteristics and potentialhazards. Matter either in their solid, a liquid or a gaseous form i. loadingis made from atoms which combine with other atoms to form ii. shipping in special purpose vesselsmolecules. Air is a gas, in any gas, large numbers of molecules iii. Unloading at the receiving terminal.are weakly attracted to each other and are free to move about iv. Third party risks to people onshore or onboardin space. A gas does not have a fixed shape or size. Each gasthat the air is composed of consists of various different NG shipping industry is undergoing considerable changes,properties that add to the overall characteristics of a particular e.g. an expected doubling of the fleet over a 10-year period,gas.[3] Gases have certain physical and chemical properties emergence of considerable larger vessels, alternativethat help to differentiate a particular gas in the atmosphere. propulsion systems, new operators with less experience newDepending on different properties the gases are used widely in trading route, offshore operations and an anticipated shortageseveral applications. Below are some of the gases properties - of qualified and well trained crew to man Liquefies gasNatural gas may consist of: carriers in the near future. i. Methane CH4 -> .80% ii. Ethane C2H6 ->.20% With this development, there is tendency for gas shipping to iii. Propane C3H8 ->20% experience an increasing risk level in the time to come. iv. Butane C4H10 ->20% Most IMO previous rules were made on reaction basis, in v. Carbon Dioxide CO2->.8% this age of knowledge employment of the new philosophy to vi. Oxygen O2 ->0.2% design construct and operate based on risk and considering vii. Nitrogen N2 ->5% holistic factors of concern for sustainability and reliabilityviii. Hydrogen sulphide H2S ->5% remain a great invention of our time to save LPG ship and ix. Rare gases-> A, He, Ne, Xe trace shipping. Hazards associated with LPG ships are linked to the gascharacteristics and beyond compliances operability and design. V. MARITIME REGULATIONCNG are a non toxic gas liquid at -259 °F / -162 °C whichignites at 1350°F / 732°C. The octane number is 120; it can The International convention for the Safety of Life at Seainflame having a share of 5.3 to 15% in air. Methane has only (SOLAS) is the fundamental IMO instrument that deal with regulation requirement for basic construction and management 58
  4. 4. Canadian Journal on Environmental, Construction and Civil Engineering Vol. 2, No. 5, June 2011for all types of ships. It covers areas like are stability,machinery, electrical installations, fire protection, detection The code specifies the ship survival capability and theand extinction systems, life-saving appliances, Surveys and location of cargo tanks. According to the type of cargo, ainspections, SOLAS also contains a number of other codes minimum distance of the cargo tanks from the ship’s shellrelated to safety and security that applies to shipping in plating is stipulated in order to protect the cargo in case ofgeneral. Examples of these are the Fire Safety Systems Code contact, collision or grounding events. Thus the code(FSS Code), the International Management Code for the Safe prescribes requirements for ships carrying different types ofOperations of Ships and for Pollution Prevention (ISM Code) liquefied gas, and defines four different standards of ships, asand the International Ship and Port Facility security Code described in Table 1. LNG carriers are required to be ships of(ISPS Code). These codes imply requirements aiming at type 2G and all LNG carriers should be designed with doubleenhancing the safety on Liquefy Gas (LG) shipping activities hull and double bottom, while 2PG type is for LPG well as shipping in general [4, 5] Classification society rules apply for structural strength TABLE 1while special code for ships carrying liquefied gas included in REQUIREMENT FOR SHIP CARRYING LIQUEFIEDthe SOLAS regulations- the IGC code. Other IMO regulations GASpertaining to safety are contained in the International Ship Cargoconvention on Load Lines which addresses the limits to which typea ship may be loaded, the International Convention for the 3G Require moderate prevention methodPrevention of Collisions at Sea (COLREG) addressing issues 2G Ship less than 150m Require significantrelated to steering, lights and signals and the International preventive measureConvention on Standards of Training, Certification and Watch 2PG Require significant preventive measurekeeping for Seafarers (STCW Convention) which addresses cargo are carried in C tanksissues related to the training of crew. The International 1G Require significant maximum preventiveConvention for the Prevention of Pollution from Ships measure(MARPOL) addresses issues related to marine and airpollution from ships. These regulations are applicable to allships as well as LPG ships. The issue of global warming has The IGC code requires segregation of cargo tanks and cargoinitiated MARPOL annex VI, was given preferential vapor piping systems from other areas of the ship such asacceptance beyond tacit procedure and there is indication that machinery spaces, accommodation spaces, control stations; itmore will follow [6] also prescribes standards for such segregation. It provides standards for cargo control rooms and cargo pump-rooms are VI. MARITIME REGULATIONS FOR LIQUIFY GAS as well as standards for access to cargo spaces and airlocks. It REGULATION defines requirements for leakage detection systems, as well as loading and unloading arrangements. Different types of cargo IMO regulation for safety regarding carriage of gas was containment systems are permitted by the IGC code, and thenever specifically for LNG, CNG or LPG carriers. However two main types of containment systems in use in the worldsafety regulations exist in order to ensure the LPG ships are liquefied tanker fleet are membrane tanks and independentsafe. Thus Gas carriers need to comply with a number of tanks. Membrane tanks are tanks which consist of a thin layerdifferent rules that are common to all ship types, as well as a or membrane, supported through insulation by the adjacentset of safety regulations particularly developed for ships hull structure. The membrane should be designed in such acarrying liquefied gas and the their crew as well as site way that thermal expansion or contraction does not causeselection and design of LG terminals. This include issues undue stress to the membrane. The independent tanks are self-relating to control of traffic near ports, local topology, weather supporting in that they do not form a part of the ship’s hull.conditions, safe mooring possibility, tug capability, safe [10]distances and surrounding industry, population and training ofterminal staff. These considerations contribute to enhance the The IGC code defines three categories of independent tanks:safety of LPG shipping in its most critical phase, i.e. sailing in Type A, B and C. Type C tanks are pressure tanks for LPGrestricted waters or around terminal and port areas. and will not be required for LNG vessels since LNG are transported at ambient pressure. Regardless of what The IGC code prescribes a set of requirements pertaining to containment system is used, the tanks should be design takingsafety related to the design, construction, equipment and factors such as internal and external pressure, dynamic loadsoperation of ships involved in carriage of liquefied gases in due to the motions of the ship, thermal loads, sloshing loadsbulk. The IACS unified requirements for gas tankers were into account, and structural analyses should be carried out. Apartly derived from the IGC code. separate secondary barrier is normally required for the gas 59
  5. 5. Canadian Journal on Environmental, Construction and Civil Engineering Vol. 2, No. 5, June 2011liquefied gas containment systems to act as a temporary 95, ISM code, tanker familiarization training, as well as flagcontainment of any leakage of LNG through the primary state or company specific training requirements that go beyondbarrier. For membrane tanks and independent type a tanks, a these international regulations [12, 13]complete secondary barrier is required. For independent typeB tanks, a partial secondary barrier is required, whereas no The competence level of Liquefied gas crew has generallysecondary barrier is required for independent type C tanks. been regarded as quite high compared to that of other shipThe secondary barrier should prevent lowering of the types. A study presented in demonstrates that the performancetemperature of the ship structure in case of leakage of the score of crew onboard gas and chemical tankers are the bestprimary barrier and should be capable of containing any among cargo carrying ships, second only to that of passengerleakage for a period of 15 days. vessels. STCW 95 contains minimum training requirements for crew engaged in international maritime trade. In particular, The code contains operational requirements related to i.e. chapter V of the STCW code contains standards regardingcargo transfer methods, filling limits for tanks and the use of special training requirements for personnel on certain types ofcargo boil-offs as fuel as well as requirements on surveys and ships, among them liquefied gas carriers. One requirement forcertification. Equivalents to the various requirements in the masters, Officers and ratings assigned specific duties andcode are accepted if it can be proven, e.g. by trials, to be as responsibilities related to cargo or cargo equipment on alleffective as what is required by the code. This applies to types of tankers, e.g. LNG tankers, is that they shall havefittings, materials, appliances, apparatuses, Equipments, completed an approved tanker familiarization course. Such aarrangements, procedures. Additional requirements regarding course should have minimum cover the following topics:insulation and materials used for the cargo containmentsystems as well as construction and testing, piping and valving i. • Characteristics of cargoes and cargo toxicityetc. are included in the IGC code. The IGC code also requires ii. • Hazards and Hazard controlcertain safety equipments to be carried onboard LPG carriers. iii. • Safety equipment and protection of personnelThese include ship handling systems such as positioning iv. • Pollution preventionsystems, approach velocity meters, automatic mooring linemonitoring and cargo handling systems such as emergency The course must provide the theoretical and practicalshutdown systems (ESD) and emergency release system knowledge of subjects required in further specialized tanker(ERS). In addition, systems for vapor, fire detection, fire training. Specialized training for liquefied gas tankers shouldextinguishing (dry chemical powder) and temperature control as a minimum include the following syllabus:are required. i. • Regulations and codes of practice In addition to the numerous regulations, codes, ii. • Advanced fire fighting techniques and tacticsrecommendations and guidelines regarding gas carriers issued iii. • Basic chemistry and physics related to the safeby IMO, there are extensive regulations, recommendation and carriage of liquefied gases in bulkguidelines under international and local umbrella related to iv. • Health hazards relevant to the carriage of liquefiedsafety LPG shipping exist that undoubtedly contributing to the gashigh safety standard and the good safety record that has been v. • Principles of cargo containment systems and Cargo-experienced for the fleet of LG carriers. e.g. standards of best handling systemspractice issued by SIGTTO (The Society of International Gas vi. • Ship operating procedures including loading andTanker & Terminal Operators) [4, 11] discharging preparation and procedures vii. • Safety practices and equipment viii. • Emergency procedures and environmental VII. TRANING REQUIREMENT protection Any person responsible for, or involved with, the operationand dispensing of LPG should have an understanding of the In addition to these training requirements, masters, chiefphysical characteristics of the product and be trained in the engineering officers, chief mates, second engineering officersoperation of all ancillary equipment. Thus acquiring sufficient and any persons with immediate responsibilities for loading,crew with the required level of experience, training and discharging and care in transit of handling of cargo in a LGknowledge of LG are believed to be one of the major safety- tanker are required to have at least 3 months sea service on arelated challenges to the maritime LG industry in the years to liquefied gas tanker. Due to the extensive trainingcome. In addition to strict regulations on the ship itself, there requirements and experience level of their personnel, theare also extensive international regulations specifying the maritime LNG industry claims that the crew sailing the LNGnecessary training and experience of crew that operate LPG fleet are among the best in the world. However, a shortage ofcarriers. These include the international rules on training experienced LG crew is foreseen in the near future especiallyrequirements are contained in regulations such as the STCW with the expected growth of the LPG fleet. 60
  6. 6. Canadian Journal on Environmental, Construction and Civil Engineering Vol. 2, No. 5, June 2011 VIII. TRANSPORTATION OF LPG INIAND WATER Ship Concept design - is very important in shipping and it account for 80 percent of failure, therefore compliance and making of optimal design has a great impact in ship whole life cycle. The impact of environment in ship design is very LPG and CNG and LNG are next in line of alterative for difficult because of large numbers of uncertainties.transportation to gasoline because of their associated Environmental impact hat need to be taken into considerationsenvironmental benefits including reduction of GHGs. Thus, it in concept design can be classified into the following:is more useful for countries with natural gas resources and a Operations: considering limiting life cycle of ships at estimaterelatively good gas distribution system. LPG has been of 25 years, issues relating to the following are equally notexplored in the 1930s but its used has been slowed because of easy to quantify in design work, even thus a lot of researchfavorable economy of petroleum. However, the current threat effort has been set on move on this, but the call of the dayof climate change has increased the focus on alternative require allowable clearance and solution to be given to thetransport fuels which include. Countries with programmes on following: Known emission, Accidental, Ballast waste,the use of CNG and LPG as a transport fuel include the USA, CoatingCanada, UK, Thailand, New Zealand, Argentina and Pakistan Commercial forces: where company that or product that[1,2] CNG and LPG are used in both private vehicles and operate in unenvironmental friendly way, people are prone totransport fleets. It is estimated that about 250 million vehicles spurn the companies products and service, there fore havingare using this fuel worldwide, and its use is on the increase, impact on company return on investment.representing 2% of total global transport fuel use. The Construction and Disposal- use of meticulous scantling andadvantages of using LPG are: factors worth consideration with the ship at the end of her life i. Environmental friendliness cycle ii. reduced engine maintenance cost Shipboard environmental protection should Pollution iii. Improved engine and fuel efficiency Prevention (P2) or Pollution Control. Pollution Prevention Use fewer environmentally harmful substances and generateHowever limitations are the following: less waste on board. Pollution Control: Increase treatment, i. Storage containment processing, or destruction of wastes on board. The basic P2 ii. High cost of conversion principles follow: Eliminating the use of environmentally iii. Need for high skill operator harmful chemicals and reducing the amount of waste we generate on board is often better that treating it on board.Each category of this required thorough, holistic risk, goal Typical environmental green house gas release from differentbased design and operability assessment for safety, reliability prime movers is shown in Table 2.and protection of environment5.1 Environmental concern- a driving force for beyondcompliance policy TABLE 2 Over the last decade, each passing years has beenaugmented concerned about issue of environment importance ENVIRONMENTAL PERFORMANCEin design, construction, operation and beneficial disposal of EMISSION LPG GASOLINE DIESELmarine articraft .the overriding force is increasing the COx 1 10.4 1.2resources of the planet that we live and that only a few are HC 1 2.0 1.2renewable. This accumulated to production that has elements NO 1 1.2 1.1of long-term sustainability of the earth. Precipitated effect over PM neg present Very highthe year has call for public awareness and translated into SOx neg neg Very highimpact through these the following manners:Regulations: public pressure on governmental and non- Emission is inherent consequence of powered shipping, Fuelgovernmental organization regulation due to untold stories of oil burning as main source, Continuous combustiondisaster and impact, the public is very concerned and in need machineries - boilers, gas turbines and incinerators. And thisof fact that if the quality of life of people enjoy is to be made the following issue very important:sustained, for them and the future generation then theenvironment must be protected. conspicuous issue, expertise i. Worldwide focus of fuel-> Exhaust gas emission lawand finding of regulations make them to go extra length on by IMO and introduction of local rulesunseen issue, contrasting between the two, while commercial ii. Emission limits driving evolution to development andforce act on hat will be forth problems. adaptation to new technology 61
  7. 7. Canadian Journal on Environmental, Construction and Civil Engineering Vol. 2, No. 5, June 2011 iii. Solution anticipated to maintenance of ship life cycle Towards sustainable reliability, it is preferable to use at average of 25 years stochastic and probabilistic methods that could help improve iv. Focus is currently more on, NOx and SOx – HC, COx in the existing methodology this method involve absolutism and particulate will soon join that will cover all uncertainty complimented by historical and v. Consideration involves not only fuel use and design holistic matrix investigation. Hybridizing models is also a plus but also operational issues. for the best solution of sustainable maintenance of navigation channel. Beyond compliance towards meeting required safety level and life cycle and environmental protection requiredTable 3 below shows the environmental regulatory demand of systematic employment of hybrid of OBS and RBS systems.out time for ships that need to be considered Below is the general step of RBS and OBS which can bein design and operation of LPG ships. apply for above described characteristic of LPG Ships. TABLE 3 ENVIRONMENTAL DEMAND FOR SHIPS X. COMPONENTS OF GOAL BASED STANDARDS Environme Environmental Demand ntal parameters Ship design Need for longer safe life cycle Objective -based standards (OBS) are ship safety standards comprising five tiers (see Figure 1): Constructi on High worker safety standards, Low energy input Level I, consists of goals expressed in terms of safety Emission Minimum pollution and emission, objectives defined by risk level. Minimum Sox, Nox and Cox, PMs-Zero discharge Level II, consists of requirements for ship Scrapping Zero harmful emission Operations Efficient maneuverability features/capabilities, defined by risk level, that assure waste, Energy Maximum fuel efficiency achievement of ship’s safety objectives. Antifoulin g Harmless LEVEL III, here Tier IV and V are to be verified for Ballast water Zero biological invasion or transfer of alien species compliance with Tier II. Sea mammal Maneuverability capability Level IV, consists of rules, guidelines, technical procedures Interaction and programs, and other regulations for ship designing and Accident Able officer, Ship structure, Integrity ship operation needs, fulfillment of which satisfies ship’s Fire Harmless Wave feature/capability requirements. wash of High speed Zero inundation and spray ashore Level V, consists of the code of practice, safety and quality Marine craft systems that are to be applied to guarantee the specified rules by quality level. IX. .HYBRID USE OF HIGH LEVEL OBJECTIVE BASED AND SAFETY RISK BASED DESIGN TOWARDS BEYOND COMPLIANCE It is clear that the shipping industry is overkilled with rulesand recent environmental issues are have potential to initiatenew rules, this made firms to selectively adopt “ beyondcompliance “ policy that are more stringent than the requiredextant law due to . Beyond compliance policy are mostly intra– firm process – which could be power based or leadershipbased. it draw insight from institutional theory, cooperatesocial performance perspective, and stakeholder theory thatrelate to internal dynamic process. While external forces createexpectation and incentive for manager, intra firm politicsinfluence how managers perceive, interpret external pressureand act on them [7, 14] Policy towards beyond compliance fallinto 2 categories: i. Whether they are now required by law but they are consistent with profit maximization. ii. Requirement by law and firm are expected to comply by them. 62
  8. 8. Canadian Journal on Environmental, Construction and Civil Engineering Vol. 2, No. 5, June 2011 RISK = Hazard x Exposure (an estimate on probability that High level Goal Assessment certain toxicity will be realized). While HAZARD: Anything -Standards Requirement Level that can cause harm (e.g. chemicals, electricity, natural - Functional Requirement 1&2 disasters) Severity may be measured by: Analysis Goal Compliance i. No. of people affected Level 3 ii. Monetary loss iii. Equipment downtime IMO Instruments Level iv. Area affected Class Guides 4&5 v. Nature of credible accident process Design process Approval Risk ranking index according to level of risk the tables bellow show an example of risk matrix (Table 4) with assignments of risk level identifies by number index. Secondary standards Table 4: Risk level matrix -for company or individual Consequence Criteria 1 2 3 4 5 ships Insignificant Minor Moderate Major Catastrophic The consequence is almost Very Very High Fig. 1: High level Goal Based Assessment A- certain to occur in most Medium (M) High (H) High (H) High (VH) circumstances (VH) The consequence is likely to Medium High Very High B- Medium (M) High (H) occur frequently (M) (H) (VH) Possible and likely for the Medium High C- consequence to occur at some Low (L) High (H) High (H) (M) (H) A. Sustainable Risk Assessment time The consequence is unlikely to Medium Medium D- Low (L) Low (L) High (H)Sustainability remain a substantial part of assessing risk and occur but could happen (M) (M) The consequence may occurlife cycle of ships– however, they are very complex and Likelihood Medium Medium E- but only in exceptional Low (L) Low (L) High (H)require long time data for accurate. Environmental risk and circumstances (M) (M)Environmental impact assessment (EIA) procedure is laid outby various environmental departments and will continue toremain similar except that the components of risk area cover Risk management is the evaluation of alternative riskdifferent uncertainty to sustain a particular system are reduction measures and the implementation of those thatdifferent. EIA has been a conventional process to identify, appear cost effective where Zero discharge = zero risk, but thepredict, assess, estimate and communicate the future state of challenge is to bring the risk to acceptable level and at thethe environment, with and without the development in order to same time, derive the max Benefit [10]advise the decision makers the potential environmental effectsof the proposed course of action before a decision is made. RBS is improvised version of EIA where holisticconsideration, community participation, expert rating, cost XI. COMPONENTS OF SYSTEM BASED SAFETY RISKbenefit analysis and regulatory concerned are core part of the ASSESSMENTphilosophy leading to reliable decision making and sustainablesystem design and operation. In risk assessment, serenity andprobability of adverse consequence (HAZARD) are deal with System based safety assessment targets:through systematic process that quantitatively measure ,perceive risk and value of ship using input from all i. Iidentification of potential hazard scenarios andconcerned- waterway users and experts [8, 14] major impact to ship Shipping and ship design which could lead to significant safety or operability 63
  9. 9. Canadian Journal on Environmental, Construction and Civil Engineering Vol. 2, No. 5, June 2011 consequences as well recent call for policies chance The risk analysis (step 2) comprises a thorough and procedural major effects investigation of accident statistics for liquefy gas carriers as ii. Verification of current design, construction and well as risk modeling utilizing event tree methodologies for the operations ensure that risk from identified scenarios most important accident scenarios, based on the survey of meet risk acceptability criteria accident statistics and the outcome of the HAZID leading to iii. If not, to recommend additional RBA process and generic accident scenarios recommendation for further risk available technology for control and protection that analysis. Figure 2 shows formal safety assessment steps. can reduce risk to suitable level.Bellow is the general RBA steps: Step 5 Step 1 Step 2 desision Step 3 Step 4 Hazard Risk and Optiions CostRBA STEPS: identification Analysis2 Control Benefit recommendatio nSTEP 1 - HAZID: The HAZID (step 1) should be conducted a in a technicalmeeting including brainstorming sessions, from various sectorswithin the LPG industry, i.e. ship owner/operator, shipyard,ship design office/maritime engineering consultancy, Fig. 2: Risk assessment and analysis stepsequipment manufacturer, classification society and researchcentre/university. The risk analysis essentially contains two parts, i.e. a frequency assessment and a consequence assessment. TheCommon identifiable hazards are: frequency assessment, involve estimation of frequency of generic incidents using reasonable accident statistics derived i. Emission to air, water and soil from the selected accident scenarios which should also be ii. Shipboard cargo tank and cargo handling equipment compared with similar studies for liquefy gas carriers as well iii. Storage of tanks and Piping as other ship. The consequence assessment should be iv. Safety Equipments and Instruments performed using event tree methodologies. Risk models can be v. Ruder failure in inland water developed for each accident scenario and event trees vi. Crew fall or slip on board constructed according to these risk models utilizing accident vii. Fault of navigation equipments in inland water statistics, damage statistics, fleet statistics, simple calculationsviii. Steering and propulsion failure modeling and expert opinion elicitation [15] ix. Collision with ship including Passing vessel hydro dynamic effects The frequency and consequence assessments provide the x. Terrorist attack or intentional incident risk associated with the different generic accident scenarios xi. Potential Shortage of crew which can be summarized in order to estimate the individual xii. Navigation and berthing procedure and societal risks pertaining to liquefy gas carrier operations and design. Based on available accident statistics and results The results from the HAZID should be recorded in a risk from the HAZID, eight generic accident scenario umbrellasregister stating total number of hazards, different operational that required deep analysis are:categories. The top ranked hazards according to the outcomeof the HAZID can be selected and given respective risk index i. Collisionbased on qualitative judgment by the HAZID participants from ii. Fire or explosiondiverse field of expert. It should emphasize on the study of iii. Groundingexisting situations and regulations including policies in place, iv. Contactspresent performance, flaws and survey on parties feeling on v. Heavy weather/loss of intact stabilityacceptability and procedures. vi. Failure/leakage of the cargo containment system vii. Incidents while loading or unloading cargo LPGSTEP 2 - Hazard analysis viii. Emission ship power sources 64
  10. 10. Canadian Journal on Environmental, Construction and Civil Engineering Vol. 2, No. 5, June 2011 The first five generic accident scenarios are general in the ii. Grouping of the measures into possible risk controlsense that they involve all types of ships; wile 6 and 7 accident options usingscenarios are specific to gas carriers and 8 concerned new a. -General approach- which provides riskenvironmental issue driving compliance and technology for all control by controlling the likelihood ofships. Selected accident scenarios to investigate frequency initiation of accidents, and may be effectiveassessment could provide a sufficiently accurate estimate of in preventing several different accidentinitiating frequencies for the eight selected accident scenarios. sequences; andFigure 3 shows risk model for explosion case. b. -distributed approach - which provides control of escalation of accidents, together with the possibility of influencing the later stages of escalation of other, perhaps unrelated, accidents. And this followed by assessment of the control options as a function of their effectiveness against risk Loading Condition Loading Condition Model Model reduction. Engine Engine room room Fire Protection Model Fire Protection Model CONSEQUENCE STEP 4 : COST BENEFIT ASSESSMENT (CBA) Cargo leakage Model Cargo leakage ModelFire ExplosionFire Explosion Model Model consequence consequence Accommodation Accommodation Risk -Cost - Benefit analysis to deduce mitigation and LPG Hazard Model LPG Hazard Model options selection Proposed need for new regulations based on Suvivability Model Suvivability Model mitigation and options Compressor Compressor room room Evacuation model Evacuation model i. CBA quantification of cost effectiveness that provide basis for decision making about RCO identified, this Fig. 3: Risk model for explosion scenario include the net or gross and discounting values. ii. Cost of equipment, redesign and construction , documentation, training , inspection maintenance and Identification of accident scenario that is significant to drills, auditing , regulation , reduced commercial used risk contribution should consider use of: and operational limitation ( speed , loads ) iii. Benefit could include , reduced probability of fatality ,injuries, serenity and negative effects as well as on health , severity of pollution and economic losses i. Holistic risk assessment of major treat using RBA and OBS oodel including application of stochastic. STEP 5 : DECISION MAKING ii. Probabilistic and deterministic methods to increase This step involves: reliability and reduce uncertainties as much as possible this including using tool comprising i. Discussion of hazard and associated risks foreseeable scenarios and scenario event, such tolls ii. Review of RCO that keep ALARP are : iii. Comparison and rank RCO based on associated cost a. Accident modeling model and benefit b. Estimation of risk, accident frequency and consequences Specification of recommendation for decision makers output could be use for “beyond compliance” preparedness and rulemaking tools for regulatory bodies towards measures andSTEP 3 - RISK CONTROL contribution for sustainability of the system intactness, our planet and the right of future generation. In order to selectRisk control measures are used to group risk into a limited between alternative technical or regulatory solutions tonumber of well thought out practical regulatory options. specific problems the first three RBA steps (HAZID, riskConsideration should focus on: assessment, RCOs) can fit into the development of high-level goals (Level 1) and functional requirements (Level 2) of OBS. i. Specification of risk control measures for identified Equally, the last three steps (RCOs, CBA, and scenarios Recommendations) could feed into Level IV and V of OBS 65
  11. 11. Canadian Journal on Environmental, Construction and Civil Engineering Vol. 2, No. 5, June 2011 XII. UNCERTAINTY risk acceptance criteria for crew and society for LPG tankers should be established prior to and independent of the actual Uncertainty will always be part of our activities because of risk analysis. The overall risk associated with LPG carrierslimitation of knowledge of unseen in real world settings, issues should be concentrated in the reduction desired areas ALARP,associated with uncertainty are normally. where cost effective risk reduction measures should be sought in all areas. Three areas or generic accident scenarios where i. Influences on recovery process which together are responsible for about 90% of the total risk are: Collision, grounding and contact, and they are related in ii. Test of new advancements that they describe situation where by the LPG vessel can be iii. Influence on policy damaged because of an impact from an external source support inland water like vessel or floating object, the sea floor or iv. Address system changes over time submerged objects, the quay or shore or bad weather. Figure 4 and 5 show prescription risk acceptability analysis graphs. v. services & resourcesEstimating uncertainty including further validation, policyissues and rating could be obtained through the relation:R(P1c) = R(E1) x W(E1,P1) + R(E2) x W(E2,P1) + R(E4) xW(E4,P1)Where R= rating, E= environmental factor, P= Policy factor Uncertainty is necessary because of highly variable natureof elements and properties involved with the situation requiresimulate of extreme condition and model – using combinationmathematical modeling and stochastic techniques whileconsidering all factors in holistic manner that cover: i. Risk areas and assessment – taking all practical using historical data’s and statistics that include all factors - Public health (people > other species) Fig. 4: ALARP diagram – Source [IMO] ii. Mitigation of risk assessment and risk areas - This - 0. 0. 1. - 0. 0. 1. - 0. 0. 1. 1. 1.0 0 5 0 1. 0 0 5 0 1. 0 0 5 0 0 involves making permanent changes to minimize 0. 0 effect of a disaster- Immediacy: (Immediate 1. A - 1.0 0 threat>delayed threats) 0. 0 - B 1.0 1. iii. Panel of expert -Reach out to those who are capable 0 0. 0 to extend hand and do the right thing at the risk area- 1. C - 1 .0 0 Uncertainty (More certain > less certain) 0. 0 - D 1.0 1. iv. Community participation - Educate all concern about 0 0. 0 the going and lastly place firm implementation and 1. E - 1.0 monitoring procedure. For adaptability (Treatable > 0 0. 0 untreatable) - 1.0 F 1. 0 0. 0 v. Emergency response – provide monitoring and G - 1.0 information facilities and make sure necessary - 1.0 0. 0 0. 5 1. 0 - 1 .0 0. 0 0. 5 1. 0 - 1 .0 0. 0 0. 5 1. 0 - 1.0 0. 0 0. 5 1. 0 information is appropriately transmitted and received by all XIII. RISK ACCEPTABILITY CRITERIA Fig.5 Matrix plot analysis of system ALARP The diagram below gives overall risk reduction areas By studying the risk models associated with these scenarios,identification and preliminary recommendation, In order to four sub-models in particular stands out where further riskassess the risk as estimated by the risk analysis, appropriate 66
  12. 12. Canadian Journal on Environmental, Construction and Civil Engineering Vol. 2, No. 5, June 2011reduction could be effective. These are the accident frequency The economic benefit and risk reduction ascribed to each riskmodel, the cargo leakage frequency model, the survivability control options should be based on the event trees developedmodel and the evacuation model. Particularly, related to during the risk analysis and on considerations on whichcollision, grounding and contact, it is recommended that accident scenarios would be affected. Figure 5 shows costfurther efforts in step 3 of this FSA focus on measures relating benefit analysis representative graph. Estimates on expectedto: downtime and repair costs in case of accidents should be based on statistics from shipyards. i. Navigational safety. improvements ii. Maneuverability. Improved maneuverability Extended use of tugs might reduce the frequency of XIV. BEYOND COMPLIANCE SHIP DESIGN contact and grounding events near the terminals. iii. Collision avoidance. i.e. warning boats in busy waters Existing design tools cannot, at least with any degree of to clear the way for the LPG carrier. reliability, be used to design a vessel to operate will ensure iv. Cargo protection. Measures to prevent spillage environmental reliability for LPG ships and operation in through enhancing the cargo containment system’s shallow or restricted waters. This is because of the extreme on- ability to maintain its integrity linearity of hull and propulsion characteristics under these v. Damage stability. Reducing the probability of sinking conditions. In general, naval architects and marine engineers though enhancement of survival capabilities in are educated and equipped with knowledge, skills, design damaged condition processes that permit continuous checking balancing of vi. Evacuation arrangements and associated consequence constraints and design tradeoffs of vessel capabilities as the through improvements relating to evacuation design progresses. procedures, escape route layout or life saving appliances. Figure 6 shows the CBA balancing The intended result of the process is the best design given process curve for sustainable design. the basic requirements of speed, payload, and endurance.Risk control options step 3 can be identified and prioritized at Focus is not placed on top down model of generic designtechnical workshops, such meting could consider identification based on risk where all areas of concerned are assessed atand selection of risk control options for further evaluation and different stages of design spiral as well as risk ofcost benefit assessment. This part of the FSA also contained a environmental consequence for risk involved in operability inhigh-level review of existing measures to prevent accidental restricted water. Operational wise, recent time has seen realrelease of gas. attempt to fully integrate human operational practices with Diferent betw cost of polution een vessel design. costt control andenvironm dam etal age M umsumof cost inim C of polutioncontrol ost H dam cost w igh age ith no control N econom gainfrom o ic polusion control C of dam from ost age polution M umsumof cost inim Fig. 6 Cost Benefit Analysis Figure 7: Ship Design Spiral Acceptable quotient-= BENEFIT RISK / COST (1) Evolving simulation technology, however give hope for assessment of extreme engineering to mitigate extreme 67