“Although Taiwan is surrounded by the sea, the general public does not have a deep feeling for the ocean.” Zhang Genmu pointed out that most people in Taiwan may go to the seaside less than once a year. Without getting close to the ocean, they would naturally not put too much emotion into it. Concerned about related environmental issues. But the undeniable fact is that oil pollution is indeed a serious problem in Taiwan today. “Although we stipulate that waste oil cannot be discharged at sea, many fishing boats and foreign merchant ships will discharge waste oil in the waters of Taiwan.” In addition, shipwrecks, strandings, and ship damage may also spread due to oil pollution. Many follow-up processing problems.
In response to the subsequent development of the oil spill of the Panamanian cargo ship Dawning in the sea off Shimen, New Taipei City in 1997, Guo Zhaowei, secretary general of the Marine Environmental Education Promotion Association, pointed out that after the incident, they would lead the people to the accident site to care about oil pollution every year. issue. Whenever you pass the coastline where oil pollution occurs, you can smell an unbearable odor just a little closer.
But one day three years after the incident, a natural miracle happened to him that surprised him. “I can smell the oily smell every time I passed by in the past three years, but I didn’t smell it again after this time,” said Guo Zhaowei. “When I took a closer look, I found that it was Ulva ulva, an algae that grows in March and April, and it is a plant that can withstand moderate pollution.” He pointed out that the surrounding stone areas were originally polluted by heavy oil. A lot of green plants appeared in the block and the surrounding ecosystem is slowly beginning to recover.
It was only then that Guo Zhaowei suddenly realized that the oil pollution problem that could not be removed by man was at that time, and nature had quietly begun to clean up through the power of plants. “At that time, the oil pollution problem that mankind spent years unsolved was actually solved by the power of nature!”
Oil pollution treatment vs. environmental protection
When a large-scale oil spill occurs at sea, the oil product will affect the oil pollution diffusion speed according to its viscosity, specific gravity, chemical composition and fluidity. The ocean current and wind speed are the main factors that affect the direction of the oil spill.
According to the specific gravity of oil, it can be divided into light oil and heavy oil. Light oil can be prevented from spreading on the surface of the water by using oil barriers, and evaporates under sunlight and decomposes under the action of microorganisms in the water, but the evaporation and decomposition speed is slow; the spreading area of oil pollution increases more than ten times, covering the sea surface and causing seabed organisms to become hypoxic , And heavy oil with higher density is easy to sink into the water. In addition to its high viscosity, the emulsification phenomenon after being affected by sunlight and wind will reduce the decomposition rate. If it drifts to ecologically sensitive areas, the damage it causes is more difficult to estimate .
Zhang Genmu said that when Taiwan is facing an oil spill, the main method of removal will be to lay an oil barrier within the first time to limit the spread of oil. After blocking the oil, use oil-absorbing cotton to absorb the oil as much as possible, and finally use an oil extractor to prevent the oil from floating to the shore through mechanical extraction, and minimize the damage to the environment.
However, if the oil pollution has landed ashore, it will deepen the difficulty of removal. For example, in the oil spill of the local freighter “Dexiang Taipei” in the Republic of China in 105, the hull of the ship was ruptured due to the impact of wind and waves, and the location of the incident was about 500 meters offshore. , The oil spilled landed in less than 2 hours. The treatment method can only be the same as cleaning the floor, using manual cleaning, wiping with oil-absorbing cotton, and then diluting with a strong high temperature and high-pressure water column, and finally using oil-absorbing cotton again to remove the dirty water.
However, the impact of oil pollution is comprehensive and wide-ranging. Chen Xiaohua, Chief Executive Officer of the Disaster Prevention and Water Environment Research Center, said: “Basically, oil pollution treatment is very difficult! And it is impossible to completely restore it. In the end, it can only be restored by nature. , Let nature slowly eliminate it.” The severity of the oil pollution incident will cause biological changes in the entire region, making it difficult to restore its former vitality.
Oil pollution treatment provokes controversy
Degreasing agents are long-chain chemical agents that are often used when marine pollution occurs. Using the interface activity principle similar to soap, chemical molecules surround the oil to form small oil droplets, which is convenient for dilution and biodegradation. However, because the degreaser itself is a toxic substance to organisms, it may cause fish or birds to accumulate toxins through the food chain to death, and even affect humans. This has reduced the number of cases of oil spills using degreasers in recent years.
Zhang Mugen stated that Taiwan began to use degreasers after a certain oil pollution incident a few years ago, but after controversy arose, they did not dare to use them rashly. “Because most people will have a negative view on the safety of the degreaser itself, and worry about whether the degreaser will cause the organisms around the sea to eat by mistake, which will lead to poisoning, and even more fear of causing secondary pollution to the ocean. .”
In response to the controversy over the use of degreaser, Guo Zhaowei pointed out that although its use is extremely controversial outside, it is undeniable that it is still a necessity for cleaning. “Because oil will contaminate various objects with ocean currents, what should you do if you don’t use degreaser? If you only rely on waves and ocean currents to dissolve it, the speed will be very slow, so degreaser is still useful.” It also points out that although many people in Taiwan oppose the use of degreasing agents, when the two are harmful, the lesser one should be taken. “For example, if oil pollution spreads to mangroves today, the entire mangrove forest It will all suffer. If the oil barrier can’t stop it, there will be no way without using degreaser.”
With the advancement of science and technology in Taiwan today, the Environmental Protection Agency has approved some degreasers to be used in Taiwan’s waters. “At present, Guoguang brand degreasers have passed inspections and can be dealt with when oil pollution occurs.” National Cheng Kung University Marine Technology and Affairs Research Professor Liu Gang said that most people’s criticism of degreasers lies in their ignorance of the product. “Nowadays, some new oil dispersants have passed biological experiments. Compared with the past, they are no longer as important to the environment. Impact.”