Type: Process Essays
Sample donated: Renee Gutierrez
Last updated: July 23, 2019
Introduction Environmental health is the interaction between theenvironment and human health and the resulting impacts on people’s health.
One ofthe key environmental risks to public health in developed and developingcountries is air pollution, both household (indoor) and ambient (outdoor). Acuteand long-term exposure to ambient air pollution have varying effects on humanhealth. Adverse effects from exposure lead to health outcomes requiringhospital admissions, emergency room visits, chronic illness, and possibly death.Various ambient air pollutants are linked with increasing the risk of morbiditywith regards to organ damage (e.g. kidney and liver), respiratory andcardiovascular diseases, eye and skin irritation, hormone and immune functions,neonatal development, and cancers. TheWorld Health Organization (WHO) estimated that 2.78 million deaths across theworld in 2012 were attributed to ambient air pollution where 94% of the deaths weredue to non-communicable diseases in adults (e.
g. lung cancer, ischemic heartdisease, stroke and chronic obstructive pulmonary diseases) and the remaining weredue to acute lower respiratory infection in children aged 5 and under. 1 These premature deaths could not be moreprevalent elsewhere than in the WHO Western Pacific Region (WPR) (Figure 1)where 1.
10 million (40%) of the total deaths occurred in low- and middle-incomecountries that make up the WPR (e.g. Malaysia, China, Vietnam, Papua New Guineaand Fijinorrahmah1 ).2 This statistic rendersambient air pollution as one of the largest environmental health risk for thepopulation in this region.
Thenorrahmah2 major sectors that norrahmah3 contribute to ambient air pollution andconsequently have the primary intervention roles to reduce environmental risksare transport and industry.3 Notwithstanding, themortality and burden of disease from ambient air pollution are largelypreventable through multi-sectoral efforts. The industry sector can play asignificant role in curbing air pollution through emission control and cleanerindustrial processes whereas improved monitoring and reporting of air pollutionand associated health trends by local and national agencies will allow trackingof progress and the effectiveness of policies to reduce ambient air pollution.3,4 However, industry policiesthat will drive intervention strategies on air pollution reduction is onlyeffective when they are founded upon the sector’s recognition of the reach ofenvironmental impacts and the associated public health risks from theirenvironmental releases, as well as the mechanisms that differentiate highfrom low risk emissions.
norrahmah4 The global need for fossil fuel and consumer products frompetroleum ensures that the oil and gas industry continue to be one of the keyindustrial sectors for years to come. However, the activities of the industryare known to have ambient air quality implications through emissions of airpollutants, notably greenhouse gases, photochemical air pollutants and theirprecursors, and air toxics.5 Air emissions from thesefacilities have been shown to be a determinant of the local air quality, proximalcommunity exposures to air pollutants have been much studied for associationwith cancer, morbidity and mortality, and the associated health risks are oneof the highest concerns of the population. Rarely isolated from communities, itis common for oil and gas facilities to operate near populated areas eitherbecause they were built later near residential areas that have already beenestablished or people settle nearer the facilities as a corollary of theeconomic, commercial and employment opportunities that the industry offer.
As a result, the air quality and healthimpacts of oil and gas emissions are not only cumulative at the regional andnational levels but also directly experienced at very local levels. Despite generalized trends, the exact nature of therelationship between oil and gas emissions, population exposure and the levelof health risks from exposure to air pollutants is influenced by local-specificvariables, e.g. meteorological and terrain features that affect dispersion ofair pollutants, residential distance and population density from source ofemissions that affect the population at risk, and operational characteristicsof the oil and gas facilities that influence the pattern of air emissions. Thisvariability indicates a need to understand the local-specific context thatshapes this relationship, particularly in a region where ambient air pollutionhas been identified as a critical environmental health threat.Overview and LiteratureReviewnorrahmah5 Background on the oil and gas industry and airemission sources The oil and gas industry operates off 3 main sectors with diverseactivities that are successively linked with each other (Figure 2) and their primarygoal is to transform raw petroleum to commodity (bulk) chemicals (e.g.gasoline, chlorine and sulfuric acid) and intermediate chemicals (e.
g.polyester films, polyvinyl chloride and phosphate fertilizer) for consumerproducts.6 Facilities that emit airpollutants can be found at each step in the chain of activities. To achieve economic edge, petroleum companies may opt tofocus only on a set of activities (e.g. exploration and production) or performseveral successive activities in the chain called integration (e.g.
explorationand production, refining and petrochemical manufacturing). An integrated petroleumcomplex, hence, could consist of various combination of facilities acrossmultiple sectors. An example of an integrated petroleum complex is in Kerteh,Malaysia where the operational network comprised of upstream facilities (e.g. crude oil and natural gasterminals), midstream facilities (e.g.
gas processing plants and gas transmissionpipelines), and downstream facilities (e.g. oil refining and petrochemicalplants). Large integration is typically achieved by national oil and gascompanies (NOC) because of state policies regarding the petroleum sector, e.g.industry participation, licensing and petroleum contracts.7 Air emission from oiland gas facilities originates from numerousactivities duringproduction, transportation, refining, processing, distribution and marketing of petroleum which can be groupedinto several categories. Process and combustionemissions occur as a result of the processes and activities employed to handle and treat petroleumand other materials (e.
g. acid gas removal, chemicalsweetening, catalytic cracking, use of incinerators, and flaring and venting), storage andhandling emissions occur when tanks release gas to maintainequilibrium of pressure, temperature and concentration with ambient air (e.g. loading/unloading chemicals and vaporrecovery), fugitive emissions occur when hydrocarbons escapethrough seals, valves andflanges, and secondary emissions occur when hydrocarbons evaporate from polluted water, oily residuals,sludges and wastes (e.g. waste water treatment and landfills).8Hence, emissions can be released from point, volume or area sources.
Normal operation of an oil and gas facility typicallyfollows a periodically set production schedule with the aim to maximizeproduction targets. Often, the continuous normal operation of a facility issubjected to disruptive or transient events that require the facility tooperate outside their normal operating conditions or to halt production (shutdown).The transient events could be either planned or unplanned, involve one or moreunits or the whole facility, and last for a short duration typically severalhours or days before normal production resumes. Examples of planned eventsinclude minor and major maintenance activities, scaling back production load tomeet new production target, and catalyst change.
Examples of unplannedtransient events include equipment malfunction, process upset such as catalyst orreactor poisoning, and facility emergencies (e.g. fire and toxic gas release). Plannedand unplanned events regularly involve shutdown of equipment, several processunits, or the whole facility in order to manage the events and require thefacility to carry out ‘start up’ activities to get back in operation. Start-upsand shutdowns may release higher air emissions than normal operation because ofprocess alignment activities, non-ideal process conditions (e.
g. air-fuel ratioto achieve complete combustion) and minimum/non-operation of control devicesbefore the operational system achieve normal, steady state. Throughout thisdissertation proposal, the term ‘transient events’ will be used to refer toplanned and unplanned events that results in partial or complete shutdown of afacility and the ensuing start-up activities, whereas the term ‘excessemissions’ will refer to air emissions consequent to shutdown and start-upactivities.Air pollution and health concerns associated with oil and gas emission A large number of studies showedthat the industry emits a wide range of air pollutants harmful to human health.In addition to grouping air pollutants intogreenhouse gases, photochemical air pollutants and their precursors, and airtoxics, tThecomposition of air emissions from the oil and gas industry can be classifiedinto criteria pollutantspollutants (e.g. nitrogen dioxideoxides,sulfur dioxide, and particulate matter), inorganic gases (, e.g.
chlorine, ammonia, hydrogen cyanide, and hydrogen sulfide),organic compounds, e.g. (methane, volatile organiccompounds (VOC), and polycyclic aromatic hydrocarbon (PAH)), and heavy metals, (e.g.
arsenic, lead, and mercury). Air monitoring of oil and gasemissions often found benzene, toluene, ethylbenzene and xylenes (BTEX),1,3-butadiene, formaldehyde, n-hexane and hydrogen sulfide to be most abundantand sometimes exceeding environmental and health-based standards.9–12..add morereferences on this. A significant number of public health researchis devoted to studying the patterns of occurrence,concentration levels and exposure to VOC, PAH, nitrogen dioxide, sulfur dioxideand heavy metals.9–11,13–16 Aspetroleum is made up of 50-98%hydrocarbons composedof alkanes(paraffins), cycloalkanes(naphthenes),and aromaticscompounds,17 VOC andPAH compounds are of great interest topublic health researchers fortheir cancer and non-cancer health effects.
Morethan 75 VOC compounds can be retrieved from air monitoring samplesnear oil and gas facilities9 and as many as 22 VOC carcinogenshave been found in air samples in one study18. Short term exposure toambient level PAH aggravates coronary heart diseases in people with the medicalcondition whereas chronic effects include cancers of the lung, skin and bladder,and DNA damage.19 Toxic Release Inventory (TRI)reports from crude oil refinery, natural gas processing plants andpetrochemical facilities show that these facilities emit carcinogens associatedwith cancers of the prostate, lung, bladder, kidney, breast and non-Hodgkinlymphoma (NHL).20 ..add more references on this. Communitiesnear oil and gasfacilities could be exposedto the same chemicals that workers are exposed to although at muchlower concentration levels.
21 Even at this low ambient levels, communities residing near oil and gasindustry sites have been shown to be exposed to levels in excess of air qualitystandards and in some cases, levels near the facilities were higher than thelevels in local cities.9,16,22,23 Exposure assessment ofambient air pollutants from major industrial areas, including oil and gassites, seeks to identify the population at risk. A large number of studiesdefine or attempt to investigate exposed populations within 10 km and rarelybeyond 20 km of emissions sources.
24 However, when industrialproduction and processes are modified to reduce emissions, a marked improvementin the local air quality and levels of nitrogen dioxide, sulfur dioxide, andparticulate matters were observed.25 This illustrates that oil and gas emission isan important contributor to local air pollutant levels and the population atrisk resides reasonably close to emission sources. Assuming that communities have nodirect control and are constantly exposed to air emissions, the health risks posed from community exposure could be higher compared tooccupational exposure for reasons such as the lack of systematic controls to limit exposures that are afforded in workplaces, lack of personal recovery periods and potentially long residentialduration. Aconsiderable amount of literature has been published on the health risk andimpacts of exposure to oil and gas air pollutants. A considerable amount of literature has beenpublished on the humanhealth impacts ofexposure to oil and gas air pollutants. Thesestudies showed that the industry emits a wide range of air pollutants harmfulto human health6–17 – with as many as 22 carcinogenic compounds found inone study18. Epidemiological studies have found exposedcommunities to be at increased chances of respiratorysymptoms and cancers of the lungs and bladder, leukemia, andallergic rhinitis26–30, as well as having greaterfrequency of respiratory diseases and impaired lung function than thoseunexposed.
31–34 Health risk assessments ofcommunities near petrochemical sites found that the risks of cancer andnon-cancer health effects could be elevated compared to unexposed communities.35–38 In summary, there is a strongevidence from studies worldwide that air emissions from oil and gas facilities containpollutants hazardous to public health and the associated health risks are ofconcerns to the population living near the facilities.Emissions during normal and non-normal operations Emission standards are largely developed for permitting andlimiting emissions during normal operation and excess emissions from transientevents are often excluded from reporting or permitting requirements of state regulatoryagencies. However, significant progress through tighter enforcement ofcompliance to the Clean Air Act has been made recently with the U.S. EPA’srecognition that these exclusions results in facilities to ’emit pollutantsduring such periods repeatedly and in quantities that could cause unacceptableair pollution in nearby communities’.39 A study of an ethylenefacility found that start-up emissions could release huge quantities ofpollutants, namely 22,680 metric tonne (MT) of ethylene, 3.
4 MT of nitrogenoxides, 6.8 MT of hydrocarbons, and 45.4 MT of highly-reactive VOC.40 Lack of control of excessemissions with significant consequences on population exposure was demonstratedby a study where communities as far as 8 km from oil and gas flaring wereexposed to formaldehyde levels above the health-based standards for acuteeffects.
41 Despite the potentiallyserious effects of transient events, it is common for excess emissions to be under-reportedor not reported altogether particularly when there is a lax in relevantregulations. Obaid et al. (2017) reported that close to half of the facilitiesthat reported emissions data for normal operation and start-ups providedsimilar data for shutdowns.42 X study found that …literature review on excessemissions not reported ie focus on lack of reporting. Accordingly, emissionsdata for transient events are less likely to be available in emission databasesand to be used in public health research on impacts of emissions.
Available studies on air qualityassessment of oil and gas facilities showed that the pattern of pollutantrelease is varied between emissions under normal operation and transientevents. Predicted and modelled increases in emissions of criteria pollutants, sulfur oxide, nitrogenoxide, and VOC during transient events were higher than normal operation butconcentration levels may not be high enough to exceed air quality limits.42–44 A review of an LNG facility found thatnitrogen oxides emission were lower by at least 50% during start-up andshutdown but particulate matter (PM10) emission was 18 times higher duringstart-up and 110 times higher during shut-down compared to during normaloperation.42 In contrast, another study found that maximumpollutant concentrations could be released in both scenarios.44 Therefore,environmental health studies of the impact of oil and gas emissions shouldconsider evaluating both normal operation and transient events to determineworst case scenario.
Gaps in Studies on Public Health Risks of AirEmissions from Oil and Gas Facilities Much is already known about typical air emissions from oiland gas facilities and the resultant environmental health impacts. They are animportant determinant of the local air quality and pollutant levels cancontribute to violations of ambient standards. Epidemiology studies associateemissions with various adverse health effects associated with acute and chronicexposures. However, the approach taken by a large majority of research on thepublic health impacts of oil and gas emissions has been cross-sectional innature, i.
e. data are gathered at point(s) in time with the assumption thatthey are characteristic of typical facility operation and emission mode. Moststudies in the field of public health are restricted to evaluating emissionsand air pollutants supposing that they are associated with normal operation. Studies have showed that transientevents produced sizeable quantity of air pollutants between 7-59% higheremission rates compared to emissions during normal operation.
These emissionsalso led to transient impacts on local air quality and presumably higher acuterisks to public health.45–49 Despite this and otherevidences that point to the potential public health significance of transientevents emission, they are less investigated compared to normal emissions andstudies on public health risks associated with transient events are evenlacking. Previously described lack of reporting, unavailability of published data,and inadequate emission standards regulating transient events emissions aresome of the causal factors that contribute to this gap in research. Another potentiallimitation could be due to the exclusivity of the body of knowledge regarding oiland gas and public health. While bepublic health researchers are that have been described previously The causal factors forthis gap in research can be attributed to the lack of reporting, unavailabilityof data, and inconsistent emission standards regulating transient eventsemissions that have been described previously.
There are 2 Research on the subject has been mostly restricted tolimited comparisons In addition, there is a general lack of body of researchthat simultaneously compare normal operation and transient events in the publichealth domain despite projections of increasing global demand for petroleum fuelsand products. Therefore, there is an impetus for future studies of the impactof oil and gas emissions on human health to evaluate both normal operation andtransient events to determine worst case scenario. A substantial volume of air emissions, air pollution andhealth risk assessment studies have been carried out for individual types of facilitiessited together (e.g.
crude oil processing terminals or refineries andpetrochemical manufacturing complexes). However, there is a dearth of publishedstudies on air emissions from integrated petroleum operation which consists ofmixed facilities such as the site in Kereth, Malaysia. The lack of studies ofintegrated petroleum facilities results in a lack of knowledge on theircombined emissions and attributable impacts on local air quality and publichealth risks. Despite the economic and environmental importance of thepetroleum industry in Malaysia, theimpacts of air emissions at current production rate on the populations at riskin Malaysia have not been characterized. This results in a critical gapin knowledge for current and future tracking of health risks as there is nobaseline information to compare with within the local context. Despite the growing number of studies linking petroleumemissions with air pollution, health risks and diseases, there is a lack ofsimilar studies in Malaysia. Incontrast, there have been multiple studies in Thailand, Taiwan, and China 4,13,38–47 that gave valuable insight on theinteraction between the local petroleum industry and public health.
The void inknowledge demonstrates an immediate need for research in this area for severalreasons: first, the petroleum industry could be a significant contributor tothe local air pollution; second, villages and residential areas could be foundin close proximity to industrial sites; and third, long term effects due to airpollution are often not part of routine health surveillance 50. Results and recommendations from the proposedstudy would potentially enlighten policy makers and drive informed decisions onemission controls and community exposures. The research to date has tended to focus on X (normalemission) rather than Y (excess emissions).
Most studies in the field of X have only focused on ….ResearchQuestions and Specific Aimsnorrahmah6 This dissertation intends to identify new knowledge that canbe evaluated on the characteristics of oil and gas emissions during normaloperations and transient events and the associated public health risks fromexposure to such emissions. The overall aim is to generate new data onless-researched areas of the emissions of integrated oil and gas facilities inorder to advance knowledge of their environmental and public health impacts.The long-term goal is to establish baseline data on the impacts of the industryon health risks in order to support changes to public health policies andinterventions to protect the population at risk.
The following research questions (RQ) are relevant to thisdissertation: RQ1: How does air emissions from oil and gas facilities atan integrated petroleum site differ during normal operation and transient eventscenarios over the short (e.g. months) and long term (annual)? RQ2: How does different emission scenarios impact the groundlevel concentration of air pollutants and the population at risk? Are there anydistinguishing features that are drivers of pollutant levels (e.g.
facilities)? RQ3: What level of risks to acute and chronic health effectsshould exposed population be concerned with as a result of exposure to oil andgas emissions? How does the pattern of health risks compare when exposures arebrought about by normal operation versus by transient events? Which pollutantsdrive the health risks?