Jellyfish stimulated the operation of nuclear power stations

A large number of jellyfish gathered on the beach, the operation of the nuclear power plant was suspended, and a large number of tourists were injured... This is not a description in a science fiction novel, but a scene performed in reality. In the recent past, from the United States to Japan, there has been a surge of jellyfish in many parts of the world. The researchers believe that this may be related to climate change, environmental pollution and overfishing.

Israel: Using excavators to clear jellyfish According to a report on the UK’s “Daily Mail” on July 6, the operation of the nuclear power plant in Hadera, Israel, was disrupted due to the large number of jellyfish blocking the seawater supply system used to cool nuclear reactors.

A staff member of the nuclear power plant introduced that these jellyfish come from the Mediterranean Sea. When they gather in the seawater cooling system, the secreted mucilage can block the condenser in the cooling system and even cause the nuclear power station to stop in serious cases. The nuclear power plant had to use an excavator to clean these sticky creatures. It was alleged that several tons of jellyfish had been cleared and some workers were injured during the process of clearing the jellyfish.

United Kingdom: Nuclear reactors were also shut down due to the jellyfish's outage because of jellyfish. Two nuclear reactors were closed at the end of June in the Tonys nuclear power plant in Scotland. Nuclear power plant officials said that a large number of jellyfish wandered in the sea, blocking the seawater filter of the nuclear power plant.

France's power company, which is responsible for the removal of seawater filters, said that reducing jellyfish, seaweed, and other floating substances from seawater in nuclear power plants is one of the important measures to maintain the safety of nuclear power plants. After the jellyfish blocked the screen, the cooling system was stopped and the two nuclear reactors were in a safe state. The staff was cleaning up. This incident will not pose a threat to public health, nor will it cause nuclear pollution to cause environmental pollution. EDF also said that once the number of jellyfish on the screen has dropped to a certain standard, the nuclear power plant will be re-opened.

Japan: Jellyfish Blocking Seawater Cooling Pipes After a major earthquake and tsunami, Japan’s nuclear power stations have recently encountered an “attack” by jellyfish.

According to media reports, seawater cooling pipes at the Shimane nuclear power plant in Japan were blocked by jellyfish about two weeks ago, generating a reduction of 6%. According to a spokesperson for a nuclear power plant operating company, jellyfish often appear in Japanese waters in the summer, but this is the first time since 1997 that a jellyfish has hindered the operation of nuclear power plants. However, the menacing jellyfish “retreat” a few days later, and the Shimane nuclear power plant has returned to normal.

United States: Jellyfish group stretches for tens of kilometers in Florida, USA. Jellyfish appear on the beach in a large scale and stunned the seaside tourists.

According to reports, on July 4th when people went to the beach in Volucia County, Florida, to celebrate the National Day, they discovered that a large number of jellyfish appeared between the two beaches, stretching for 32 kilometers. The scene was spectacular. Jellyfish wounded many people, but fortunately no one was seriously injured. A spokesman for the Coast Guard said that the appearance of these jellyfish in batches was not a "seasonal" phenomenon and it may have been brought to the shore by the wind and currents.

How does a coastal nuclear power plant prevent sea creatures from "disrupting"?

Nuclear power plants are usually located in water-rich coastal areas or inland rivers and lakes. At present, about 40% of nuclear power plants in the world are coastal. The cooling system of a coastal nuclear power plant requires a lot of seawater, and the seawater needs to be filtered before it is used as cooling water. How to prevent sea creatures such as sundries and jellyfish from blocking the filtration system?

Feng Yi, deputy secretary-general of the China Nuclear Energy Association, told this reporter that the first is to install filtration devices at sea water intakes, such as rotating screens, to block sea creatures and debris that may cause clogging, and be supervised by special personnel, once there are a lot of Sea creatures plug the rotating screen and immediately clean it up. At the same time, the filter should be replaced regularly to ensure the filtration effect. In addition, in order to prevent the growth of marine organisms in the condenser pipes and other equipment, seawater must be chlorinated as necessary and the pipelines should be flushed regularly.

Feng Yi said that at the beginning of site selection and construction, some coastal nuclear power stations did not face the problem of large numbers of marine invasions. Later, due to global warming and human activities, some sea areas had such problems, but technicians also Continuously improve the seawater filtration system of nuclear power plants in response to emerging issues.

Why is jellyfish so flooded?

In recent years, with the increase in the number of global marine jellyfish, many sea areas have encountered the invasion of jellyfish. In July 2008, the blue coast of the southern French resort was invaded by jellyfish and more than 500 tourists were injured. In 2009, the Echizen jellyfish, which had caused huge losses to the fishery along the coast of the Japan Sea, appeared in large numbers on the Pacific side, causing the Japanese fishing industry to suffer another heavy blow. The Echizen jellyfish is the largest jellyfish in the world. It has a diameter of up to 2 meters and weighs several hundred kilograms. Fish caught with jellyfish are either poisoned by its venom or stabbed to death, causing fishermen to complain. What causes the jellyfish to be flooded?

One reason: Over-fishing Qiu Yongsong, director of Fisheries Resources Research Office of South China Sea Fisheries Research Institute, said in an interview with this reporter that the drastic increase in the number of jellyfish may be related to overfishing. Qiu Yongsong said that some fish in the ocean have originally used small jellyfish as food, or competed for food with jellyfish, which can control the amount of jellyfish, but overfishing destroys the balance of the sea, making these jellyfish "natural enemies" reduce the number of jellyfish It will increase.

Reason two: eutrophication Richardson, a marine biologist at the University of Queensland in Australia, believes that the eutrophication of seawater may also be one of the reasons for the large increase in the number of jellyfish. Richardson said that after the eutrophication of sea areas, nitrogen and phosphorus in seawater exceeded the standard and plankton bloomed. These areas will have low oxygen content and fish cannot survive, but jellyfish can grow in large numbers. In addition, jellyfish feed on plankton, and increased plankton encourages the growth of jellyfish.

Qiu Yongsong said that the eutrophication of the sea is related to human activities. For example, urban domestic wastewater discharge, industrial wastewater discharge, and excessive use of farmland fertilizers all make nutrients such as nitrogen and phosphorus into natural water bodies.

Reason 3: Analysis of ocean acidification scientists said that the sharp increase in the number of jellyfish may be related to the increase in the use of fossil fuels by humans in recent years, resulting in the acidification of ocean water. In a report released by the UN Environment Agency in December 2010, marine biologists at the University of Plymouth in the United Kingdom pointed out that the degree of ocean acidification has increased by 30% since the start of the industrial revolution. Ocean acidification does not affect the survival of jellyfish, but it is not conducive to the growth of corals and crustaceans. The reduction of crustaceans may lead to a sharp increase in the number of jellyfish.

Reason 4: Global warming Marine biologists believe that climate warming is also a cause of rampant jellyfish. Global warming raises the temperature of seawater, making it more suitable for breeding of jellyfish, thereby multiplying the number of jellyfish. Jennifer Bursel, an oceanographer at the University of Washington, found that in at least 11 sea areas around the world, jellyfish disasters are linked to climate warming. In addition, the warming of the ocean has allowed some of the species in the jellyfish to expand their range of activities. Not only does the annual time appear earlier, but the overall number also increases.

Jellyfish is a seemingly elegant jellyfish of dangerous marine animals. It is actually a dangerous marine animal. It does not belong to fish. It is a kind of boneless soft anemone. It mainly lives in the temperate, tropical and subtropical oceans. There are many species of jellyfish. There are about 250 species around the world. The diameter is usually between 10 cm and 100 cm. The largest jellyfish umbrella can reach 200 cm in width.

The main component of the jellyfish body is water. It looks like an umbrella, with delicate tentacles under the umbrella cover. Its secret weapon is a stingray hidden in the hands. The highly-toxic barbed wire is usually curled up in the thorns. Once a foreign object is touched, it will immediately “penetrate” the barbed wire into the body of the victim and release the peptide toxin. According to the toxicity and bruising area of ​​jellyfish, the wounded person suffers from skin swelling, vomiting, diarrhea, severe shock and pulmonary edema until death. Therefore, see the floating jellyfish and do not touch it. Once it is licked, it cannot be washed with fresh water. It should be washed with seawater or vinegar.