Environmental Management in the Oil, Gas and related Energy ...

April 2013, Volume 4, No.2 International Journal of Chemical and Environmental Engineering

Environmental Management in the Oil, Gas and related Energy Industries in Ghana O-W. Achawa,* , E. Danso-Boatengb a Department of Chemical Engineering ,Kumasi Polytechnic, Kumasi, Ghana b Department of Chemical Engineering, Loughborough University, Loughborough, UK *Corresponding AuthorE-mail:[email protected]

Abstract: In view of the past experiences with the oil, gas and related energy industries in the West African sub-region, there is increased apprehension among Ghanaians on how the recent oil find would impact the environment and whether the nation has the requisite expertise and capacity to manage the oil in an environmentally friendly manner. The apprehension is further heightened by the generally perceived weak environmental regulatory regime in the country. The study used plant and institutional visits, interviews and questionnaires to investigate the waste management practices of four major companies in the oil, gas and related energy industries in Ghana. It sought to find out among others the nature of waste generated by these entities, how the waste they generate are handled, to what extent their activities impact on the environment, the sort of uses to which the waste are put, and the regulatory regime within which they operate. The study revealed that the activities of all the companies impacted on water bodies in their catchment area. Only two (2) out of the four (4) industries studied have comprehensive waste treatment facilities at their plants. The study further revealed that the Environmental Protection Agency of Ghana (EPA-Ghana) has not been able to sanction those companies violating its regulations. Unless EPA-Ghana and other relevant regulatory bodies rigorously enforce the environmental regulations of the country, the environment of Ghana will continue suffer degradation as a result of the activities of the oil, gas and related energy industries. Keywords: Ghana; environment; oil waste; regulatory bodies; waste management; Environmental Protection Agency

1. Introduction The oil, gas and related energy industries, as a result of the huge volumes of products they churn out, also generate significant waste which when not properly handled are known to cause a lot of damage to the environment [1-3]. Right from the well head where the crude oil is produced, through the refinery processes, down to the final point of utility, potential threats to the environment exist. At the well head, the degradation of flora and fauna as a result of movement and activities of heavy duty equipment is imminent [4]. Flaring of associated gas releases combustion gases into the atmosphere; these gases have been established to contribute to acid rain and climate change. Also, leakages and spillage of oil as a result of equipment failure can sometimes lead to catastrophe onto the environment. The much publicized April 2010 oil spillage in the Gulf of Mexico by BP Oil Company is a case in point [5]. During transportation and storage of crude oil and natural gas similar hazards lurk. The 1985 Exxon Vadez accident provides an example in this regard. Crude refinery and natural gas processing activities produce, among others, huge quantities of oily wastewater, lower molecular weight hydrocarbons, heavy metals, organic and inorganic compounds of sulfur, and the oxides of nitrogen

and carbon among others. These waste materials have adverse implications on the environment when they are released without treatment. The combustion of natural gas and oil products to produce energy either for electricity generation, operation of internal combustion engines, or for other commercial uses results in the production of large volumes of combustion gases. These gases inevitably enter into the environment and contribute to climate change. More often than not, these materials also directly affect human health when they come into contact with the body. In order to control, manage or eliminate the environmental hazards associated with the oil, gas and related energy industries, technology and regulations are often the preferred instruments of choice. Technology can help minimize the occurrence of accidents and hence damage to the environment. For instance, double hulled ocean going tankers have mitigated the high incidence of oil spillage into the oceans as a result of collision or grounding [6]. Technology is also used to foster rapid response when a threat to the environment is imminent [7]. When pollution of the environment finally occurs, technology is often used to restore the environment or mitigate the impact of pollution on the environment. Regulatory bodies on the other hand provide guidelines, monitoring and sanctions regimes that check the industry

Environmental Management in the Oil, Gas and related Energy Industries in Ghana

and thus encourage, advice or compel players in the industry to adopt measures and technologies that minimize or eliminate threat to the environment. In Ghana, the recent discovery of oil and gas in commercial quantities has suddenly heightened public awareness of the potential dangers to the environment that the production, processing and utility of oil products can pose. The recent spillage of toxic drilling mud [8] into the maritime boundaries of Ghana by Kosmos Energy, an oil exploration company, and earlier ones by Tema Oil Refinery (a local refinery company) into the Gulf of Guinea [9] have awakened the nation to what it stands to lose if care is not taken even as it celebrates its oil find. The experiences of other oil producing nations in the West African sub-region, particularly, the Niger delta of Nigeria, provide useful lessons in this regard [10, 11]. It is, for instance, estimated that between 1976 and 1996, a total of 4,835 incidents resulted in the spillage of at least 2.4 million barrels of oil, of which an estimated 1.89 million barrels were lost to the environment in the Niger Delta of Nigeria alone. 1.1 Objectives This study used industrial visits, interviews, and questionnaires to investigate the potential threats to the environment of the anticipated exploitation of the recent oil find in Ghana. Specifically, it sought to identify the specific wastes produced by industries working in the crude production, crude oil refinery, petroleum and related products storage, and thermal power plant facilities that utilize hydrocarbons as the main fuel. It also sought to study the technologies available at these industries to treat the crude oil and related products wastes, the potential uses for the waste as well as the regulatory regimes within which the industries operate in Ghana in order to assess the extent of compliance of these companies. It is anticipated that the results of this study will inform the development of measures to curb the potential threat to the environment that will inevitably accompany the exploitation of crude oil and related products in commercial quantities in Ghana.

2. Methods and Materials Only those industries that responded to an invitation to participate in the exercise were included in the study. The industries covered included those in crude oil and natural gas production, crude oil processing, petroleum and related products storage, and thermal power production. The national regulatory agencies, namely, the EPA-Ghana and the Factories Inspectorate Department of the Ministry of Employment and Social Welfare, Ghana (FID-Ghana) were also included. The study employed industrial and institutional visits, interviews, questionnaires, and desktop studies for the investigation. Planned visits to the plants were also undertaken during which a walkthrough of the facilities were carried out with guidance from technical personnel. During the visits, observations were

made of equipment, waste generation and handling, and the general operations and organization of the plants. Unit managers of the plants and departmental officers were interviewed wherever necessary. Lastly, literature on environmental and waste management in the crude oil exploitation and related industries and the legislative regime regarding environmental practices in the Ghana were also reviewed. The results of the study were qualitatively analyzed.

3. Results and Discussions The list of companies and institutions that participated in the study is shown in Table 1. The choice of plants and institutions was dictated by the extent of their presence in Ghana, but also so that a holistic view of the industry with regard to the impact on the environment would be achieved. The crude oil production company operates an offshore facility in Ghana and its main product is crude oil. The refinery company operates a complex facility that includes a crude distillation unit, a residual catalytic cracking unit, a Merox unit, a sulfur production facility, an array of waste treatment units, and storage depots for crude oil, liquefied petroleum gas, and refinery products. The thermal power plant produces electricity from Table 1. Relevant companies and institutions studied Company/I nstitution Crude Oil Production Crude Processing Bulk Oil Storage Thermal Power Plant Monitoring Agencies

Number in Ghana

Number Visited/ Interviewed

Percentage Coverage (%)

2

1

50

1

1

100

8

1

12.5

4

1

25

4

2

50

hydrocarbons (petroleum and natural gas). Its facilities include combustors, gas and steam turbines, generators, process water treatment units and an array of waste treatment entities. All petroleum and related products storage facilities in Ghana are currently owned and operated by the government. Nationwide, eight such facilities exist whose main functions are the reception and storage of petroleum products and distribution of same to retailers scattered across the country. They also stock and oversee the strategic oil reserves of the country. Also, on Table 1 are the environmental regulatory bodies in the country. EPA-Ghana is the main regulatory body which by an Act of the Parliament of Ghana is mandated to among others, monitor and enforce environmental regulations in the country. Others bodies who play a complementary role, especially, where environmental and waste management in the crude oil and related industries is concerned are the Ghana National Petroleum Company, the Ministry responsible for shipping, and the FID-Ghana. EPA-Ghana and FID-Ghana were included in the study.

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Table 2. Types of wastes generated by companies

3.1 Waste generated by the companies All the companies studied generated waste as shown in Table 2. The types of waste generated by these companies include solids, liquid effluents and gaseous emissions. The crude processing company generated the widest array of waste followed by the thermal power plant. Understandably, the bulk oil storage company generated the least amount of waste as its activities do not necessitate the processing or conversion of materials. The core of oil waste from this industry stemmed mostly from leakages and occasional spillage that occur during the discharge and loading of crude oil products. Each type of waste generated by the industries has the potential to impact negatively on the environment if not treated before disposal into the environment. The potential effects of the waste generated by the industries studied on the environment are summarized in Table 3. The effects of these waste are numerous and varied. Some have very serious consequences on the environment if not checked. Gaseous emissions like carbon dioxide and methane (offgas) have serious implications on climate change [12], while others like sulfur dioxide and the oxides of nitrogen are known to cause acid rain [13] which affects forest cover. Oily wastewater if not treated before discharge can affect aquatic life if it enters water bodies, or flora and fauna if disposed onto the land. On the land the oil can seep into aquifers and thereby adversely affect their use for domestic purposes. The oil can also stagnate on the land for years and render it useless for agricultural purposes. Evaporation of hydrocarbons and other compounds from leaked or spilled oil pollute the air and can cause respiratory and other diseases when inhaled [14].

Industry

Waste Generated

Crude Production

Spent chemical solutions, waste oil, plastics, toxic drilling mud, empty drums, office and domestic waste.

Crude Processing

Process effluents (oily wastewater, sour water, desalter wastewater, spent amine solution, spent cuastic), oil free wastewater, metal scraps, spent catalyst, charcoal bags, drums, oil sludge, sewage, CO, CO2, H2S, SOx, NOx, NH3, off-gas, office and domestic waste.

Bulk Oil Storage

Waste oil, domestic and office waste.

Thermal NOx, SOx, CO, CO2, particulate matter, oily Power Plant wastewater, oil free wastewater, oil-contaminated solids, oil sludge, empty drums, office and domestic waste.

The location of these industries further complicates the possible effect of the wastes they generate on the environment. For instance, all the plants in this study are located close to water bodies and urban centers. Thus, the effluents from the plants if not properly managed, could flow into the water bodies and affect aquatic life with implications to the health and economic life of adjoining communities. Similarly, gaseous and particulate emissions from these plants have direct consequences on the health of the urban population in the catchment areas of the plants. 3.2 Waste handling by the companies The manner the companies involved in the study manage the waste they generate is shown in Table 4. The waste management approaches can be grouped into three, namely, waste reuse, direct waste dumping and waste treatment prior to disposal. Mostly, the solid wastes are not treated in any of the plants studied. They are either sold for reuse or dumped to disposal sites. The gases and liquid effluents however receive some treatment before disposal in some cases. Wastes that are reused or recycled are metal scraps, empty drums, treated oil sludge and recovered oil. While the companies sell the metal scraps

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Environmental Management in the Oil, Gas and related Energy Industries in Ghana Table 3. Potential effects of wastes generated on the environment

Waste Type Scraps Empty drums

Sludge Spent catalysts Plastics Charcoal bags Particulate matter

Potential Effect Litter the landscape and limit land usage. Litter the environment and obstruct movement; serves as breeding grounds for mosquitoes; leaks residual chemicals into environment. Hurts aquatic life and limits surface water usage; destroys flora and fauna on land; renders land unfit for agricultural use; disrupts economic activities such as fishing and recreation if it occurs in the sea. If not disposed properly become nuisance to land and water bodies; associated heavy metals are poisonous. Litter the landscape, limit land usage and choke drainage systems. Litter the landscape. Pollutes the air and causes respiratory diseases.

Office waste

Litters the landscape and limits land usage; could be source of fire.

Food waste

Gives bad odor and serves as breeding ground for microbial agents.

Process effluents

Oil free wastewater Oily wastewater

Off-gas H2S Sour water

Pollute water bodies, aquifers, and gives bad odor; they can be sources of microbial breeding, pollution of flora and fauna; renders land unfit for agricultural and domestic use. Pollutes water bodies and aquifers; are source of microbial growth. Pollutes water bodies, adversely affects flora and fauna; affects land use and human health; disruptive of economic activities such as agriculture, fishing and recreation. Causes climate change, pollutes surrounding air, affects human health Has very bad odor, pollutes air; is poisonous to human health. Has very bad odor, affects flora and fauna, pollutes water bodies and affects land use.

Sewage

Bad odor and sources of municipal diseases.

NOx/SOx

Has bad odor; causes acid rain and hence adversely affects flora, fauna and land use.

Oil-contaminated solids Drilling mud

Litter the landscape, can be source of fire. Pollutes water bodies and land; affects aquatic life and land usage.

and empty drums to dealers, the recovered oil is either recycled for use in the plant or sold to secondary users. For instance, the refinery company recycles recovered oil to its catalytic cracking unit. On the other hand, the thermal power plant sells the recovered oil to secondary users. All other solid wastes are dumped at land filling sites or collected by municipal waste agencies. The wastes in this category include office wastes, spent catalysts, food waste, plastics and charcoal bags. It is only the crude refinery and the thermal power plants that were found to treat the process wastes prior to disposal. The bulk oil storage facility has no waste treatment facility neither has the crude oil production company. The bulk oil storage facility in particular generates relatively little oily waste which is either collected in waste ponds or allowed to drain off or washed into a nearby stream. The crude oil production

company on the other hand collects and ships off its oily waste, mostly oily mud and production chemicals to secondary agents for treatment or disposal. Associated gas generated by the latter company is however flared on site. All liquid effluents and gaseous emissions except fugitive emissions receive one kind of treatment or another prior to disposal in those companies that treat their wastes. In these companies, elaborate waste treatments facilities exist to treat liquid and gaseous waste. Table 4 shows the facilities available for waste treatment at these plants. These include comprehensive wastewater treatment plants that deal with both oily and non-oily wastewater, and some process effluents. The wastewater treatment unit of the crude oil refinery plant, for instance, combines physical, chemical and biological processes. The corresponding facility in the thermal power plant uses physical and chemical methods to treat mainly oily wastewater. Other wastewater treatment.

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Environmental Management in the Oil, Gas and related Energy Industries in Ghana Table 4. Waste treatment methods employed by the companies Waste Types

Treatment Methods

Scraps

Sold for reuse

Empty drums

Sold for reuse

Sludge

Landfill, sold for use as fuel or used to make concrete

Spent catalysts

Landfill

Plastics

Municipal collection

Charcoal bags


Particulate matter

Electromagnetic separators (EPS)

Office waste


Food waste


Process effluents

Multi-stage wastewater treatment (physical, chemical and/or biotreatment)

Oil free wastewater

pH adjustment followed by disposal

Oily wastewater

Gravity separation or wastewater plant

Off-gas

Flared

H2S

Stripping unit

Sour water

Stripping unit

Spent caustic solution

pH adjustment and discharge in drain

Sewage

Oxidation ponds (stabilization and degradation by natural processes)

NOx/SOx

Not treated

Oil-contaminated solids

Landfill or municipal waste collection

Drilling chemical mud

Sent to secondary party for handling

units in these plants include gravity separators, chemical ponds, sour water stripping units, and neutralization sumps among others. Gaseous emission treatments units in the crude refinery plant include a stripping unit, and a sulfur recovery unit that treats H2S, SO2, and NH3 laden effluents. Also, a flaring unit exists to combust gaseous hydrocarbons. In both plants electrostatic particle separating units are available to separate particulates from gaseous streams. The specific waste handling methods in the various plants studied and the state of these units are listed on Table 5. All the waste treatment units in the thermal power plant function and most are in use. Only the incinerator was not in use at the time of the study and this is because the company sells its recovered oil instead of incinerating it. The company therefore had no use for the incinerator as of the time of the visit. On the other hand most of the waste treatment plants in the refinery plant are either non-

functioning or only partly functioning. Out of the six independent waste treatment facilities in the plant three do not function at all. Only two are fully functioning. The wastewater treatment plant that treated most of the process effluents only functions partly. It presupposes that the company disposes off its effluents and gaseous emissions without any treatment at all or only partly treated. Given that the plant is situated in an urban setting and close to water bodies, this situation has serious adverse implications for the surface water, surrounding flora and fauna, and the health of inhabitants in the surrounding communities. The specific effects of the wastes generated by these plants on the environment are shown in Table 6. Wastes from each of the plants affect water bodies. The oil production company’s activities directly affected the open sea, and for that matter aquatic life. Additionally, its operations impacted negatively on fishing activities of the local community. The bulk storage company leaked oil into an adjoining stream and a marshy land and thereby polluting these entities. This situation has on several occasions elicited complaints from the adjoining communities. Leaked and spilled oil evaporated and polluted the surrounding air. Oily wastewater and process effluents from the crude processing company were disposed off into a nearby lagoon and treated wastewater from the thermal power company was disposed off into a nearby marshy land which drains into a stream that flows into the sea. Again, both the crude oil refinery and thermal power companies emitted carbon dioxide and the oxides of nitrogen and sulfur into the environment. These gases have been established to contribute to climate change and acid rain. Besides, spilled or leaked petroleum products from these plants emitted volatile organic compounds that polluted the air. Hydrogen sulfide, ammonia and sulfur dioxide emissions in the crude oil processing plant polluted the air of the plant and nearby communities and thereby affected the health of employees and inhabitants of the communities. 3.3 Compliance with environmental regulations All the companies studied are aware and apparently operated according to the EPA-Ghana guidelines. This means that effluents, emissions, and disposal of wastes from these plants supposedly meet EPA-Ghana approved guidelines. Furthermore, the environmental performances of the companies are evaluated on regular basis by EPAGhana. EPA-Ghana has recently introduced an evaluation scheme dubbed AKOBEN [15] to check environmental pollution by industry. The AKOBEN program is an environmental performance rating and disclosure

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Environmental Management in the Oil, Gas and related Energy Industries in Ghana Table 5. Observed effects of wastes generated by the plants Industries

Waste types

Effect on environment

Waste crude oil

Aquatic life of the sea Affected fishing activities

Crude production Spent chemicals

Crude refinery

Bulk oil storage

Aquatic life of the sea

Combustion gases

Climate change, acid rain

Oily water

Affected nearby lagoon

NOx, SOx

Acid rain

CO2

Climate change

Spent caustic

Nearby lagoon

Process effluents

Nearby lagoon

Leaked/spilled oil

Polluted surrounding air

Waste oil

Marshy land/stream

Leaked/spilled oil


Wastewater Thermal plant

Drained into a marshland and a stream

CO2

Climate change

NOx, SOx

Acid rain

Leaked/spilled oil


initiative that assesses the environmental performance of mining and manufacturing companies in the country using a five-color rating scheme. Every year the results are disclosed to the public with the objective to strengthen public awareness and participation in pollution and environmental issues. The scheme relies on public ridicule to get companies to engage in good practices. It was introduced in part to address EPA-Ghana’s inability to strictly enforce its regulations. This weakness has resulted in a situation where violating companies got

away with environmental abuses without any sanction. The weakness stems in part from of a generally weak regulatory regime in Ghana. Another important factor that restrains the EPA-Ghana from enforcing its regulations is economics, specifically, the monopoly enjoyed by some of the companies in the Ghanaian market. For instance, the oil processing company is the only one in the country that processes and supplies crude oil products. Thus, if it were made to shut down for non-compliance of environmental regulations, it could lead to a sudden shortage of certain petroleum products in the country- a situation which would have serious economic and political ramifications in the country. Consequently, such companies are able to flout environmental regulations with impunity. Indeed, in this study, the crude oil processing company was found to have flouted the EPAGhana regulations on emissions and effluent discharge levels, yet it had not been cited by the EPA-Ghana for violation of its regulations. Thus, in order to make up for its inability to enforce its rules, EPA-Ghana is seeking to use public opinion through the AKOBEN disclosure schemes to bring pressure to bear on the companies to comply with its regulations. The performance of the companies investigated in this study, on the basis of a number of regulatory variables of the EPA-Ghana, is shown on Table 7. Significantly, none of the companies had been cited for violation of environmental regulations by the EPA-Ghana as of the time of the study. However data from the companies themselves indicated that two of them had actually violated EPA-Ghana rules on gaseous emissions and effluent discharge levels. It is noteworthy in this regard that the refinery company, for instance, operated its Residual Fluid Catalytic Unit (RFCU), even though its wastewater treatment unit was not fully functioning. This meant that process effluents from

Table 6. Performance of companies as per some regulatory guidelines Monitoring Parameter

Industry Crude Production

Crude Refinery

Bulk Oil Storage Plant

Thermal Power

Standards used

EPA & ISO1400

EPA & Insurance

EPA

EPA & World Bank

Monitoring Agency

EPA

EPA

EPA

EPA

Frequency of monitoring by EPA

Monthly

Quarterly

Regularly

Regularly

Environmental permit

Yes

Yes

Yes

Yes

Recent accidents

None

Yes

None

None

Breach of regulations

Yes

Yes

Yes

None

Community Complaints

Yes

Yes

Yes

None

Environmental Officer

Yes

Yes

Yes

Yes

Regular Reports to EPA-Ghana

Yes

Yes

Yes

Yes

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the RFCU were only partially treated before discharge into the environment. Indeed, a condition for the operation of the RFCU is that the wastewater treatment plant be functional. Yet, in spite of the quarterly visits by the EPA-Ghana, the company had not been cited for violation of the environment as of the time of the study. Among the companies studied, only one, namely the refinery plant, had had a major accident that impacted significantly on the environment. All the companies have internal personnel in the form of environmental officers who monitor the internal activities and advised management on environmental compliance and waste management related issues. These officers also prepare and submit regular environmental reports to the EPAGhana and the company management. Records from the companies showed that the FID-Ghana had not visited any of the companies as of the time of the study. FIDGhana, on the other hand complained that lack of logistics hindered its ability to deliver on its mandate. This has created a situation where some companies are violating environmental

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regulations without been being brought to book..

4. Conclusion Waste management practices of the oil, gas and related energy industries in Ghana were examined in this study. Results of the study reveal that the operations of all the companies involved in the study negatively affected the environment. The activities of the oil production company, the crude oil refinery company and the petroleum products storage company have already had adverse impact on water bodies. Only two of the companies had facilities in place to treat the waste they generate. It was observed that only the thermal power plant managed its operations such that it did not elicit any complaints from communities in its catchment area. Only one out of the four (4) companies studied had had a major oil spillage that had significant adverse effect on environment. Among the regulatory agencies only the EPA-Ghana monitored the activities of the companies on regular basis. The activities of two (2) of the industries were found to consistently violate the environmental regulations of Ghana. Therefore, unless the EPA-Ghana rigorously enforces its environmental regulations the activities of these industries will continue to degrade the environment of Ghana.

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