windy city rainy season

The two-week academic exchange time is not short. In addition to introducing their own research topics, American professors also gave a series of lectures, including the historical development and structural system of American environmental regulations, air and water pollution control technologies, and environmental risk analysis. , and waste classification and treatment methods.Tao Yu didn't know how much these Chinese graduate students could accept. He listened to the whole process and gained a deeper understanding of a sound environmental protection system.

Most of the time passed without knowing it, and the arrangements for the last few days were relatively easy. The last lecture ended in the morning on the penultimate day, and a basketball friendly match was held between China and the United States in the afternoon.The Chinese team participated in the competition were young professors in their 40s and 50s, while the US side barely pulled the average age of the middle-aged and elderly teams below [-] years old because of the joining of Tao Yu.

Don't look at Tao Yu's young age. Compared with his teammates, he is obviously less aggressive. He relies on his body to play forward flexibly. When he was shooting, he was thrown down by the defender. He injured his ankle before halftime, and he limped to the field He pulled up the hem of his T-shirt to wipe his sweat.

"Senior Brother Tao, your back is broken!" A few students watching the battle behind him shouted to him.

"No?" Tao Yu stretched out his hand to touch his back in bewilderment, but he didn't feel any pain.

"It's not broken, it's a tattoo!" A student took a closer look. Tao Yu's white T-shirt was wet with sweat, sticking to his back with a faint red color.

"What kind of tattoo, let's see if it works?"

"Do American students have more tattoos?"

"How long does it take to tattoo such a large pattern..."

The students asked questions in a hurry, and Tao Yu pulled the hem of his clothes in embarrassment, trying not to let the fabric stick to his back.

Chen Li also left the stage. Seeing Tao Yu surrounded by several people, he came over and asked, "What are you doing?"

"Mr. Chen, we want to see Brother Tao's tattoo, he's embarrassed!" the students said with a smile.

"What's so good about tattoos..." Chen Li said solemnly, taking advantage of Tao Yu's unpreparedness, he suddenly held him down, and the translucent T-shirt stuck to his back, showing a pattern of an angel with wings spread.

"Did you see it? Run while he confiscated the tickets."

A few students walked away laughing and laughing, Tao Yu pushed Chen Li helplessly: "Is there a teacher like you!"

Chen Li asked indifferently: "Is it an angel?"

"The Guardian Angel of Judaism."

"Do you believe in Judaism?"

Tao Yu bent down to pick up a bottle of mineral water and said, "You can't get a tattoo if you don't believe me?"

"It's better to tattoo a land father."

Tao Yu almost spit out a mouthful of water.

"How are your feet?" Chen Li changed the subject and asked, "Go to Yangzhou tomorrow, can you leave?"

Tao Yu moved his ankle, it hurt a little but not serious: "It's nothing serious, just go back and rinse with cold water."

Chen Li stopped a student and said a few words. The student nodded and ran away. After a while, he came back and handed something to Teacher Chen. Chen Li handed it to Tao Yu.

It was a bottle of Yunnan Baiyao. Tao Yu took it over and unscrewed the lid and said, "It's nice to be a teacher, and you can make students run errands. It reminds me of when the class leader helped the teacher's house to carry the Chinese cabbage for winter storage in elementary school. It's nice to be dragged to work." It's a fart."

"You were a class leader when you were young?" Chen Li asked.

"No, so I don't have a chance to move cabbage, so I can't judge advanced."

"Changing the way to hurt the teacher."

Chen Li took the spray and patched his ankle a few times, put the medicine bottle aside, and the two sat side by side to watch the game.At this time, the organization of the two teams was completely messed up. The American professors couldn't tell which Chinese student belonged to their team. They passed the ball randomly and made various own goals. The players who played and watched were very happy.

Tao Yu looked at the field and smirked, and heard Chen Li ask: "Do you have any injuries on your back?"

Just now the other party was pressing on the scar with one hand, Tao Yu knew that he couldn't get past it, and said indiscriminately: "...it's left from the appendicitis operation."

"Which hospital cuts the appendix and operates from the back?"

Tao Yu smiled without explaining, and Chen Li didn't ask any further, vaguely guessing the meaning of the guardian angel.

On the penultimate day, the exchange meeting organized a visit to Yangzhou, including a domestic waste-to-energy project in an environmental protection industrial park and an intelligent monitoring system for ambient air quality that will be launched soon.

The waste energy supply technology in the United States is relatively mature, mainly because the waste treatment in the United States basically adopts the landfill method. The main components of the fermentation gas are methane and carbon dioxide, which are collected through the underground gas recovery system and transported to surrounding factories to replace natural gas. energy.The methane content is an important indicator of the energy supply efficiency of waste. The methane content in natural gas is more than 90%, but the methane content produced by waste fermentation is not stable. Domestic waste can reach 50-60%, while industrial waste is much lower.In addition, methane and carbon dioxide are both greenhouse gases. American professors gave some reference opinions on how to regulate and control them.Air quality monitoring is the strong point of the old Andrew. He gave some suggestions on the selection of monitoring points, as well as what kind of statistical analysis and how to interpret the collected data to make it more representative.

It took more than half a day to visit these two projects. In the afternoon, I organized a tour of the famous scenic spots in Yangzhou, and stayed in a local hotel in the evening.This is the last night for the American professors in China. They return to Shanghai early the next morning for a brief closing ceremony, and then fly back to the United States in the afternoon.

After dinner, the professors walked to see the night scene. Old Andrew had to rest earlier as he got older, so Tao Yu sent him back to his residence.Afterwards, he didn't bother to go out alone, and stayed in the room to call Chang Zheng. As expected, after three rings, he was transferred to voicemail—it was morning in Chicago, and it was time for the doctors to make early ward rounds.

After leaving a message for the other party, Tao Yu went to the bathroom to put half a tank of hot water, sat on the edge of the bathtub while soaking his feet while scrolling through Weibo, suddenly a new friend reminded him, he opened Weibo called "Environmentalist Chen Li" , I nodded my head and went in to take a look. Most of them were all kinds of environmental protection information, some were forwarded and some were commented by myself. Occasionally, there were some public welfare news about children looking for children on Weibo. I saw that the blogger was a well-behaved academic.

"Old-fashioned!" Tao Yu smiled, and followed him.

After a while, he received a private message from "environmentalist Chen Li": Are you playing cards?In Teacher Fang's room.

Tao Tao Tao Yu: Which room does Teacher Fang live in?

Environmentalist Chen Li: Opposite you.

Tao Yu dried his feet, put his mobile phone and room card into his pocket, and walked to the opposite side in his slippers.After entering the door, I found that several people had already gathered in this room to upgrade. Seeing him coming, Mr. Fang told him to wait and add him again.Tao Yu is not addicted to playing cards, he just wants to chat with everyone when he is about to leave.He randomly found a seat and sat down, only to find Chen Li facing him.

While playing cards, Teacher Fang asked casually, "Has Xiaotao ever visited a domestic factory before?"

"I visited a power plant before." Tao Yu said, "I majored in thermal engineering for my undergraduate degree. After graduation, I worked for two years, mainly doing projects for power plants."

"How do you feel about the two places you visited today?" Another professor asked.

Tao Yu said honestly: "I feel that the technology is learned from developed countries, but it has been improved locally. When I went to work a few years ago, the construction design was copied from foreign countries, the drawings were all original, and the equipment was installed and operated for a period of time. There will be problems of one kind or another, and the difference in the emission concentration ratio will affect the operation. In recent years, the domestic environmental protection industry has changed a lot. My mother is also an engineer. She is in charge of business and has a good understanding of technology. She said that most of the environmental protection manufacturers are now independent. Production design, even if foreign technology is applied, will be improved, which is more suitable for domestic conditions.”

Professor Fang said: "Yes, localization and improvement is a crucial step. There are always some people who think that foreign technology is better, just like the United States engages in landfills, and some people criticize why domestic incineration causes air pollution. The United States has fewer people, There are some places where landfill can be done. Is it possible in China? Big cities like Beijing and Shanghai cost a lot of land and build a garbage dump with hundreds of millions of land. Is it to bury garbage or bury gold!"

Some people said: "It's good to engage in waste-to-energy like Yangzhou, waste utilization."

Chen Li played the last card and said: "Waste-to-energy can only be piloted in a small area at present, which has something to do with what kind of garbage is received and the speed of non-oxidation. I heard from the project leader that they only collect food waste from the catering industry. The degradation rate is fast, and the methane content produced is relatively stable. If the underground protection is well isolated, it should have no impact on the soil and groundwater. The only problem is the smell, and the odor produced by fermentation is difficult to deal with.”

Tao Yu said: "A sewage plant in Chicago has newly adopted a deodorizing technology, mainly for ammonium sulfate compounds. To put it bluntly, it is a large-scale spraying of deodorant. The specific formula is a patent. I don't know. The plant is on the periphery of the plant. Install a sprayer at a certain distance, spray that liquid into the factory area, and let them completely react and consume the pollutants before they spread out. I think the effect is quite obvious, but it costs water. The ratio of liquid to water is 3:97 Mixed, it’s okay in the south where there is no shortage of water, but the cost is too high in Beijing.”

Chen Li asked: "What's the name of that technology?"

Tao Yu said, "I'll check and send it to you."

Professor Fang asked: "Mr. Chen wants to do this?"

"Let's find out first." Chen Li said, "I talked to the person in charge of the waste-to-energy project in the morning, and he was also worried about the smell. The industrial park is still relatively far away from the residential area, so it's hard to say how the city will develop in the future."

"Xiao Tao, do you want to return to China after graduation?" Professor Fang said, "The school welcomes talents with foreign education to come back to teach, who can bring new ideas and technologies. You can see that your brother is doing well. He is now a project of the department. the most."

Recently, Tao Yu has been struggling with the issue of whether to return to China after graduation, and now he is most afraid of others talking about it, so he used Chen Li to change the subject and said: "My brother is a talent, and he is good at research and development projects. Back then, my boss didn't want to let him go. let's go."

He smiled and looked at Chen Li, just in time to meet his gaze, the focus in that gaze seemed to have some kind of meaning, which made him pause for a while involuntarily, but the opponent had already turned his head to look at the cards in other people's hands.

Everyone played until after ten o'clock, and some older professors couldn't bear it anymore and wanted to rest, so the game broke up, and everyone went back to their rooms.

Tao Yu went back to his room and surfed the Internet for a while, then got up and stood by the window looking at the street outside, suddenly feeling reluctant for no reason.This is his country, but it is no longer his home.

There was a knock on the door from behind, and he walked over and opened the door. Chen Li stood outside, holding a bottle of beer in one hand.

"Drink?"

"Only two bottles?"

"Two bottles are enough."