In 1936, a biogas digester built in our Putuo Mountain flood-rafting workshop opened the history of modern anaerobic technology in China. In Lettinga's memory, China was a very successful country in implementing anaerobic wastewater treatment system. This is due to the biogas usage policy that China has long implemented in rural areas. However, the use of biogas only opens the curtain of anaerobic history. How China anaerobes from the application of experience-based engineering to the industrialization of modern science and technology, how to take root, grow, transform and mature in China, and is widely used , These stories deserve our exploration. The historical materials and precious photographs in this article are selflessly provided by academician Qian Yi, Professor Hu Jichang, Professor Wang Kaijun and Ren Hongqiang, and hereby express our heartfelt thanks.

Anaerobic / Zheng Yuanjing

Compared to China's overall social and economic development, our environmental protection is undoubtedly leading the way. Returning to the Stockholm Environment Conference in 1972, China's leadership has been aware of the study of environmental pollution. At the same time, due to the large-scale establishment of Chinese industrial enterprises at that time, "Nende died fish", "Guanting reservoir pollution" and "Tuanjiehu smelly" were all the "environmental public events" of concern during that period. Under the principle of "keeping the old path of the West and demonstrating the superiority of socialism," environmental protection has been established as a basic national policy and water treatment scientists and engineers have obtained better working conditions. With the end of the ten-year turmoil, the rise of state construction and the implementation of the three simultaneous systems, China's environmental protection business entered a period of rapid development in those few years, under the inspiration of reform and opening up and the construction of the motherland.

1978, 1979, for the world history of anaerobic development, the most important. In the past two years, the Lettinga team's research results on UASB have emerged in the world academia and set off the wave of research and development on anaerobic technology. This wave naturally swept China where environmental protection is on the rise. However, amazingly, three or four years later, in 1982, China's first wastewater treatment plant using UASB technology entered the engineering pilot phase in the Beijing fermented bean curd factory. This rate is amazing even today (interested readers can compare membrane technology applications to AMX and aerobic granular sludge). Not to mention taking into account the efficiency of information dissemination at the time, the Chinese counterparts can not find more information, but also unable to communicate in real time advice, then the emergence of this speed is undoubtedly a miracle.

The key figure to realize this miracle is Zheng Yuanjing, when he was deputy director of the Beijing Environmental Protection Institute (currently Beijing ASTRI). According to Lettinga's literature, he is the first person in China to take the lead in developing UASB technology and to promote the use of the technology in the food industry. Wang Kaijun once commented on his mentor: Mr. Zheng Yuanjing is a rare masterful person in our country who has innovative thinking but has been forgotten by the industry. He is the only one in China that has such advantages as hydrolytic-aerobic, contact oxidation and anaerobic USAB Pioneering work and outstanding achievements of everyone.

This assessment elicited our concern for this audience. However, unfortunately, the memory of the modern search engine on Mr. Zheng Yuanjing, but also very few words: Zheng Yuanjing (1934 ─) Han, Fujian cents Tourists. Leningrad School of Architecture and Engineering graduate. Former Beijing Research Institute of environmental protection researcher, director, deputy director, Beijing Municipal Environmental Protection Bureau deputy director, chief engineer, Beijing eighth, nine, ten people's deputies. Enjoy the "special government allowance" issued by the State Council. 1998 hired as Beijing Municipal People's government counselor.

History is sealed over time. The story about the veteran is no longer reproducible. However, in order to avoid leaving an anaerobic development history blank, we tried hard to capture the clues from Wang Kaijun's oral dissertations from Mr. Zheng Yuanjing's own scientific research articles.

In 1975, Mr. Zheng Yuanjing led the team to begin a small-scale pilot and medium-scale pilot project to treat urban sewage using biological contact oxidation and conducted a mechanistic study of this process. The development and application of this technology was largely in keeping with the contemporaries in Japan at that time (the technology was the core process unit of a popular buried sewage treatment plant in Japan). At present, this technology has gradually evolved into the aerated filter process (BAF).

In 1982, with his promotion, China's first wastewater treatment plant using the UASB process entered its engineering pilot phase in Beijing's fermented bean curd factory. April-September the same year, Mr. Zheng Yuanjing in the "Environmental Protection" magazine serialized six articles entitled "high concentrations of organic wastewater treatment," the article, these six articles, a comprehensive and systematic anaerobic technology mechanism, process equipment As well as in the application of high concentrations of sewage treatment prospects. It now appears that these six articles seem to have become Mr. Cheng's most profound and comprehensive description of anaerobic technology left in the network.

Around 1985, Wang Kaijun division from Zheng Yuanjing, two people developed a hydrolysis - aerobic joint process. This process is a crescent, is the successful application of system theory in the field of sewage treatment, that is, the use of anaerobic acidogenic stage as a follow-up aerobic pretreatment process, greatly reducing the hydraulic retention time and improve the biodegradability of sewage. Hydrolytic acidification is currently the "standard" for the treatment of most industrial refractory wastewaters, and undoubtedly requires solid expertise, romantic imagination and the courage to innovate during the founding stage.

Time can not stop one of you in the anaerobic history of the curtain call curtain, but looking back at Mr. Zheng Yuanjing's article, we can still strongly feel that, in addition to the achievements of scientific research, he conveyed the "sewage organic Is an energy source, "and" Anaerobic biological treatment is a good way to recover energy and purify sewage. "The concept of pollution control, such as converting industrial wastewater treatment plants into water resource plants, is still widely respected by environmentalists. His efforts in the field of environmental protection and anaerobic development have also turned Chun Chun into a nourishing generation of environmental scientists and workers.

The anaerobic event, held every two years from November 11 to November 15, 1985, the fourth session of the International Symposium on Anaerobic Digestion (Biogas), was held in Guangzhou, China. The conference attracted 6 of the 50 countries in the world More than 10,000 participants attended the meeting, with 150 delegates from China participating in the conference. The participating scholars conducted exchanges and discussions on such topics as global anaerobic dynamics, basic and theoretical research, agricultural applications, industrial applications, biogas and the environment.

This meeting is undoubtedly a trend of storm blowing the frontier of anaerobic world information in China. It prompts the rapid development of efficient anaerobic wastewater treatment technology in China and greatly promoted the research on anaerobic wastewater treatment in China. It was also this year that Lettinga visited the research institutes in Beijing and Chengdu, met Qian Yi, a famous Chinese environmental scientist, and also saw the news of her visit to Taiwan on television (Qian Yi's father is famous This year, a young man named Kai-Jun Wang bragged to invite Professor Lettinga to his unit - Beijing Central Academy of Sciences visit a pilot project, when he was engaged in a large-scale up-flow hydrolysis tank Demonstration project research. Somewhere in the arrangement, has long laid an embarrassment for the anaerobic technology in China's great development.

Perforated Metal Mesh

Perforated Metal Mesh, (also named Perforated Sheet, Perforated Metal) refers to the metal sheet products with various different holes on the surface. There are many kinds of punching wire mesh products. Different shapes, different sizes of holes, can adapt to different needs.

Material: Stainless steel, low carbon steel plate, galvanized, PVC, cold rolled coil, etc.

The types: pattern perforated sheet, forming perforated plate, extra thick punching net, ultra thin punching mesh, micro porous perforated sheet metal, wire cutting punching net, Laser punching net, etc.

Shape of Hole: Rectangular hole, square hole, diamond hole, round hole, hexagonal hole, cross hole, triangle hole, long round hole, long waist hole, plum blossom hole, fish scale hole, pattern hole, five pointed hole, irregular hole, bulge hole, etc.

Use: Sound-absorbing materials for ceilings and wall of buildings; Exquisite decorative board for building staircase, balcony, environmental protection desk and chair; Machinery and equipment protection cover, grille gorgeous, food, feed, mine mill sieve, sieve screen, I-beam, stainless steel kitchen equipment, food cover, blue fruit and other kitchen utensils, and shopping malls with shelves, exhibition decoration, ventilation network for grain depot, football turf seepage water filter and so on.

Size: 1.Thickness of coil: 0.2mm-1mm; Length: 20m

2. Diameter of hole: 1.5mm-10mm

3. Thickness of plate: 0.2mm-20mm;Width*Length≤1.5m*5m

4. Diameter of hole: 0.5mm-200mm

Hole diameter:

Generally speaking, the aperture size is approximately greater than or equal to the thickness of the plate, which is in accordance with the principle of minimum pore diameter. The closer the diameter of the hole to the thickness of the sheet, the greater the difficulty of processing and the higher the processing fee.. In some raw materials, the hole size can be less than the thickness of the plate.

Pitch

The pitch is the distance between the middle of a hole and the other one, the nearest hole in it. The middle distance is a way to represent the interval between holes, and the other is the rate of opening. The essential meaning of the two representations is the same. So you just need to identify one of them.
Arrangement of holes: (detailed picture explanation)
We can make all kinds of difficult passes and patterns. Although special requirements for pass and pattern require a specified processing fee, the quotation for the usual pass is quite reasonable.

(1) 60 degree staggered row
60 degree staggered row is one of the most popular choices with its natural high strength and wide aperture ratio and attractive appearance
(2) 45 degree staggered row

Compared with the former, the 45 degree plum blossom provides another choice for people.
(3) Straight Row

Another kind of round hole placement is straight row, straight row can also have a variety of holes and opening rate, but it is the hole in the series of the worst compressive strength.

Structure:

Perforated Metal Mesh,Perforated Metal Aluminum Mesh,Stretched Perforated Metal Mesh,Stainless Steel Perforated Metal Mesh

Anping Xinzheng Metal Wire Mesh Co., Ltd , https://www.sievingmesh.com