Human Practices

Summary

After determining our general objectives, we first launched a public-oriented survey in order to understand the general public's views on our subject; then we visited the government environmental protection agencies, printing and dyeing enterprises and College of Environmental and Resources Science of Zhejiang University, visited relevant experts and industrial practitioners, and wanted to know more about the use and pollution of azo dyes in Hangzhou. Based on this information, on the one hand, we clarified the objective of the project, on the other hand, we should make clear the advantages and disadvantages of synthetic biological methods, so as to adjusted and perfected our project as well as improve the apply design and make it more practical.

Furthermore, we promoted and organized public educational event, public articles through our self-media platform to let more people know the environmental problems caused by the pollution of printing and dyeing wastewater that we are facing as well as the potential role of synthetic biological technology in water pollution control. In addition, we have also organized online fundraising. On the basis of understanding our project, the public supports our work with donations and encourages us to invest in our project with greater enthusiasm.

1.Investigation on general public’s views

In order to know the general public's understanding of printing and dyeing wastewater and the pollution caused by it, we have made a questionnaire. The online questionnaire is made through the questionnaire network and it is conducted simultaneously through offline visits and network distribution.

In this survey, 306 valid questionnaires were collected, mainly from Hangzhou City, the capital of Zhejiang Province, and its surrounding areas, covering people of different ages and education background (see Fig.1), which reliably reflected the attention and understanding of people from all parts of Hangzhou city and its surrounding society on printing and dyeing pollution. It fully confirmed the social significance of our project and provided a reference for us to carry out the science popularization of azo dyes and the design for degradation system of azo dyes.

The results of the questionnaire and its analysis are as follows:

It can be seen from the data in Fig.1 that more than 90% of the respondents in our survey have a high school diploma or above, which truly reflects that Hangzhou, as an economically developed city in China, has a high level educational citizen, whom has the ability to fully obtain information through school education, public media and other means. The level of understanding should be representative. In the conversation with the interviewees, the vast majority of people are concerned about the water pollution. According to the data in Fig.2, since people in Hangzhou is relatively well educated, more than 60% of them have some understanding of printing and dyeing wastewater and its disposal.

However, according to the results of Fig.3 and Fig.4, although many people (61.8%) pay attention to the treatment of printing and dyeing wastewater, the majority of public (86%) do not know much about the specific principles of the treatment of printing and dyeing wastewater, which could be related to the fact that printing and dyeing plants as well as sewage disposal has little association with the general public life.

The same situation also occurs in the following questions The results of Fig.5, Fig.6 and Fig.7 show that more than 80% of the general public have very limited knowledge of printing and dyeing wastewater, especially with azo dyes and its environmental risks. The results above show that even in Zhejiang Province, where printing and dyeing industry is well developed, the general public has little knowledge of the environmental problems caused by sewage under the existing conditions. This provides an important reference for us to prepare our work with public science popularization and educational events.

According to the data in Fig.8, nearly 90% of the people seldom or never found the problem of randomly discharging sewage into the natural water body. On the one hand, it shows the government's attention to environmental protection in recent years, it echoes the results above; on the other hand, it shows that a large number of polluting enterprises have moved to areas far from city and the opportunities for ordinary people to know are limited. The data in Fig.9 also shows the public's confidence in the government's treatment of printing and dyeing wastewater. Therefore, we chose Hangzhou Municipal Bureau of Ecological Environment, the government department of printing and dyeing wastewater treatment in Hangzhou as the first stop of our experts interview.

Conclusions

Citizen in Hangzhou and its surrounding areas, as well as the local government, has attached great importance to the environmental problems including water pollution. In recent years, the government has actively and effectively controlled the water pollution. The fact of public and the relevant government departments pay close attention on these problems proves the importance of our selected projects. The construction of biological machines by synthetic biology provides a new idea for sewage treatment, and also has a very positive social significance. However, the public in the provincial capital cities of a printing and dyeing industry well developed province have limited understanding of risks of wastewater, especially azo dyes. Therefore, the popularization of relevant knowledge through various ways becomes a focus of our future work.

2.Interviews with professional institutions and experts

2.1 interview with Hangzhou Municipal Bureau of Ecological Environment

Through the interview with the staff of Hangzhou Municipal Bureau of Ecological Environment, we know more about the situation of pollution and treatment of azo wastewater in Hangzhou.

According to the official in charge of industrial waste water control in Hangzhou Municipal Bureau, printing and dyeing industry is an extremely important industrial sector in Hangzhou (especially in Xiaoshan District where our school is located). At the peak period (the end of last century and the beginning of this century), about 1 / 7 of the world's dyes were produced in Xiaoshan, among which azo dyes are an important category. On the one hand, printing and dyeing industry contributes a large proportion to the local economy of Hangzhou (especially Xiaoshan District), on the other hand, due to the large industrial density, it causes serious pollution problems.

During the interview, the staff introduced the general treatment process of azo wastewater in industrial production, and the principle is shown in the figure below.

The wastewater containing azo will go through anaerobic treatment first, then through the structure with porous cilia. With aerobic bacteria attached to the cilia, azo will be converted into small molecular compounds. After the gradual bond breaking, strong oxidant will be added for further decomposition, and finally flocculation method will be used for treatment. The cost of this method is relatively economic, generally costs about 15 RMB per ton in the normal production cycle, and the total time of wastewater treatment is about 10 hours.

Therefore, in the existing printing and dyeing wastewater treatment process, the use of bacteria for biological treatment has become one of the important parts of the treatment, which shows that it is very feasible for us to design and manufacture microbial machines for the treatment of azo wastewater by using synthetic biological methods. Officials of the environmental protection bureau also suggested that we should visit some printing and dyeing enterprises to better understand the actual process in the production line.

Moreover, we also realized that generally azo is not directly used as the indicator in the detection of printing and dyeing waste liquid. One important reason is that the current methods, such as gas chromatograph, can detect the azo content qualitatively or semi quantitatively. The detection process is very complex and expensive. Therefore, when the Environmental Protection Bureau conducts the investigation and analysis of pollution accidents, it has to detect the existence of chromaticity or intermediate period. To this end, the staff of the Environmental Bureau suggested that if we make such a biological device, it can reflect the characteristic structure of azo, for example, using fluorescent protein to make the azo content a visual indicator for environmental detection. It also provides a very valuable direction for the improvement of our future project.

2.2 Visit of Hangzhou masterly bleaching and dyeing Co., Ltd.

Following the advice of the officials of the Environmental Protection Bureau, we visited Hangzhou masterly bleaching and dyeing company, a local printing and dyeing enterprise.

Under the guidance of Mr. Pan from Hangzhou masterly, we mainly visited their technological process of wastewater treatment.

This process adopts the anaerobic hydrolysis + contact oxidation biochemical treatment process, no physical and chemical sludge is produced, and the water quality is stable, so many indexes are better than the current discharge standards. The whole treatment system is divided into upper and lower structures with convenient management and low cost. See Fig.10 and 11 below:

During the visit, we found that in the biochemical tank of the process, there was a certain danger. The liquid flow rate was fast, the internal temperature was high, and the odor emitted was suffocating. The white foam appeared on the surface of the liquid.

The picture below (Fig.12) shows the scene of biochemical pool.

In view of the problems of fast liquid flow and high temperature, after discussion with engineers, we have considered the devices that can be used to fix and protect the bacteria in the future. One is to reduce the risk of engineering bacteria being washed away by high-speed water flow, and the other is to ensure that they can fully play their role under the current conditions. This field trip provides important references for our apply design.

2.3 Interview with Mr. Hu Hong (Associate Professor, senior engineer), deputy director of experimental teaching center of environment and resources, College of Environmental and Resources Science, Zhejiang University

At the same time, in order to further deepen our understanding of the existing sewage treatment methods in the printing and dyeing industry and improve our project, we visited the school of environment and resources of Zhejiang University and listened to the suggestions of relevant experts. (See Fig.14 and Fig.15)

After listening to the introduction of our project ideas and answering our questions, Professor Hu supported us to pay attention to environmental protection and solve practical problems in the way of engineering practice. In view of the current situation of great environmental pressure in the developed printing and dyeing industry in Zhejiang Province, he affirmed the project with significance and put forward three suggestions emphatically:

1) Focusing on the cost

There are different kinds of dyes, and the treatment methods will be different. Our water treatment is targeted. The first thing to be determined in the engineering design is the water quality. Then after this is determined, the composition and concentration can be determined, and then the treatment process can be determined. If a biological machine does not have universal applicability, it will increase the cost of disposal. In addition, there may be mutation in the engineering bacteria itself, and the bioreactor needs to be added regularly, which also increases the cost. In engineering application, the effect of engineering bacteria is good, but the cost may be high, and the high cost will affect the promotion.

2) Paying attention to sewage treatment indicators

There are two major indicators for sewage treatment, one is decolorization, which we will call dilution multiple, the other is organic matter concentration, COD and BOD. There are also ways with nitrogen and phosphorus, such as adding corn flour, some phosphates or urea. To adjust the proportion of carbon, nitrogen and phosphorus is not necessarily in line with the discharge standard and the destruction of the chromophore does not mean that it will not cause other effects, such as eutrophication, so comprehensive consideration should be taken in the design of process flow.

3) Simulating carefully the industrial environment

In order to verify our biological machine function, we can use simulated industrial wastewater, but it is better to use the wastewater from printing and dyeing factory. Because the composition of industrial wastewater is complex, it will be difficult to fully simulate it in the laboratory.

3.Education and Public Engagement

Based on our previous survey results, in addition to the science popularization activities with the theme of synthetic biology, we have greatly increased the publicity on the environmental risks of printing and dyeing wastewater, especially azo wastewater, so that more Hangzhou citizens can understand that the printing and dyeing industry will not only drive the local economy, but also cause major problems to our environment if the wastewater treatment cannot be effectively controlled.

Our public educational activities includes online and offline aspects.

3.1 Offline activities:

Public event in China Hangzhou Low Carbon Science and Technology Museum

In Sunday August 4^th 2019, we cooperated with other iGEM teams (ASTWS-China, ZJU-China, worldshaper-Shanghai, XHD-WS-Wuhan-B, HZNFHS-Hangzhou) to carry out public activities in China Hangzhou Low Carbon Science and Technology Museum. (See Fig. 16 and Fig. 17)

The main participants are teenagers and ordinary citizens. Before the event, we publicized the event through wechat public account, Hangzhou low carbon museum website and other channels to attract interested people to participate in the event.

The main content of the activity is to popularize some basic knowledge of synthetic biology and arouse children's interest in synthetic biology through a series of small biological games (such as DNA base pairing).As our main target is teenagers, we attach great importance to the science popularization and interest of the whole activity. We hope that participants can take this activity as a relaxed and happy game, enjoy and learn a lot from the game, and arouse their interest in biology. At the same time, we introduce our project to parents of children, popularize the environmental risks caused by azo dye printing and dyeing wastewater, and our synthetic biological solutions. The activity lasted for 6 hours, and the number of people participating in the activity on that day was estimated to be 500 to 800.

3.2 Online - self media operation

Our team continues to operate our team's wechat public account. After two years of accumulation, we have nearly thousands of fans. Considering that our public account has a certain audience and is easy to spread and produce, the online public education system continues to present our wechat account on platform this year.

Through the public account, we mainly published the activities being carried out by the team, the progress of our project, and articles about the treatment of printing and dyeing wastewater, azo dyes, synthetic biology, etc. (See Fig.18) As the main object is the masses with general education level, its content follows the principle of easy to understand. In this way, we let the public know what we are doing and why we should do so to get more public support for our project.

3.3 Online - crowdfunding

In order to carry out project research, project implementation and public science popularization activities, we decided to raise funds from the public. Based on our understanding of our project, the public has donated more than $2000 to us through the online crowdfunding platform (see Fig. 19) as well as directly personal donation to express their support for our work. The public participated in our project in this way and encouraged us to devote more enthusiasm to our work.

4. Integrated Human Practices

From the survey and interviews mentioned above, we received feedbacks from general public as well as specialists, such as government employee from Hangzhou Municipal Bureau of Ecological Environment and professor from College of Environmental and Resource Science, Zhejiang University. All of them did have grave concerns on environmental issues including water pollution problems to be caused by printing and dyeing wastewater. These positive feedbacks and the generous donation from general public demonstrated their support and encouraged us that our project about azo dyes wastewater treatment is good for everyone and does benefit the public.

However, we also found some problems from results of survey and interview, received comments and suggestion from the experts. These results and feedbacks helped us to better clarify the objective of our project and improve the project design, demonstration and apply design, education and public engagement.

4.1 Objective of the project

The original idea of our project is entirely out of love for our hometown. Hangzhou is famous for its two water-related United Nations cultural heritages, the west lake and the grand canal, and we are proud of our beautiful hometown. However, with the development of industry, water pollution problem has also become a great public concern. Because the printing and dyeing industry well developed, Hangzhou is facing the threat of dyeing wastewater pollution, and azo dye is one of the important categories. We confirmed the public's high concern about water pollution in the survey, moreover, learning from the interview with Hangzhou Environmental Protection Bureau, we realized that Hangzhou, our hometown, especially Xiaoshan district, where our school is located, is facing such great pressure of printing and dyeing wastewater pollution. Therefore, we further defined our task and determined to develop a biological disposal system for azo dye wastewater in printing and dyeing industry.

4.2 Project design

1) Version 3.0 of Azo degradation system

During the interview with professor from College of Environmental and Resources Science Zhejiang University, Prof.Hu raised an important issue: cost. Cost includes construction cost and use-cost. Use-cost also includes material cost and efficiency, or time cost. The cost directly determines the future promotion value of our project.

According to the interview with the environmental protection bureau, we learnt that common industrial wastewater treatment method currently costs 15 RMB per ton of wastewater and takes about 10 hours to dispose. Based on our current experimental results, regardless the unclear cost of cultivation and release of engineered bacteria, the disposal time of at least 48 hours is already at an obvious disadvantage.

In addition, from the actual use environment of the factory, if engineered bacteria are directly put into the existing disposal system, its living environment and safety control are both problems. In previous public activities, people have given more consideration to biosafety, so it is an important factor to prevent the escape of engineered bacteria while ensuring their working efficiency. After discussion with the engineers for factory, a solution of adding a special container is proposed, which will inevitably increase the manufacturing and use-cost of the system.

Therefore, based on the results of surveys and interviews, we believe that finding a new solution that can effectively reduce the use-cost is extremely important for the future promotion of our project. Besides a thorough discussion with our instructor and advisors, including Prof. Huang, Dr. Dong, Dr. Shi, Dr. Zhai, Dr. Guo and Ms. Song, we also visited Prof. Zhu Xufen from College of Life Science Zhejiang university, an expert in microbiology and genetic engineering. After discussion, we found that the main disadvantage of the original projects (both of version 1.0 and 2.0) was system's dependence on engineered bacteria. In fact, enzymes rather than engineered bacteria are used to degrade azo dyes. If the engineered bacteria could be removed from the system and replaced with direct enzyme delivery, the disposal time would be significantly shortened. Therefore, according to the suggestions of Prof. Zhu and other experts, we proposed version 3.0, i.e. ScLac plus Osmy surface display system, which is to replace the intracellular expression system with the extracellular expression system. The extracellular expression system provides a potential for the direct acquisition of enzymes. If the production efficiency might be improved continuously, the cost of enzymes should be controllable. Therefore, although we have not completed the plasmid construction and functional test of version 3.0 due to time constraints, we estimated that the 3.0 solution was completely feasible according to the exsiting results and literature. Once completed, it was expected to solve the two major disadvantages of processing cost and processing efficiency.

2) Azo bio-detector

During the interview with Environmental Protection Bureau, the stuff proposed a low-cost azo bio-detector that could be used to the environmental monitoring. This suggestion had also attracted our attention. However, after discussion with experts such as Prof. Hu, Prof. Huang and Prof. Zhu, we found that the use scenario of this kind of bio-detector is not very clear. Firstly, azo dyes have a specific color, which is easy to be found when they leak into the natural environment, and the color will fade once they degrade. Therefore, it is not necessary to develop a bio-detector to detect pollution or confirm whether the pollution is completely solved. Secondly, current bio-detectors mainly use color protein or fluorescent protein as reporter gene, but the effect of color gene reporting is poor in the colorful environment, and fluorescent protein as reporter gene is bound to need the cooperation of fluorescence detection equipment, which increase the use-cost. Thirdly, for azo confirmation during pollutant analysis after pollution so as to determine specify treatment scheme, we can directly use our degradation system by observing degradation effect, and there is no need to develop special detector, neither. Therefore, we decided to keep azo wastewater treatment system as the core work or our project.

4.3 Demonstration and Apply design

During his interview, Prof. Hu explained the important difference between laboratory testing and actual sample testing, emphasized the complexity of industrial wastewater, and suggested that we should try our best to obtain real wastewater. Therefore, we abandoned the original plan of manual configuration of simulated industrial wastewater and decided to collect industrial wastewater in order to test our system in real environment so as to improve our apply design. It is also proved that there was a certain difference between actual wastewater treatment results and lab-made wastewater.

In the apply design, the factory engineer, professor Hu and other experts gave us some good suggestions, such as considering sterilization before discharge to avoid the risk of escape of engineered bacteria, for example, using UV lamps to fully illuminate water bodies .

4.4 Education and Public Engagement

In our original plan, we assumed that the public already knew a lot about environmental pollution problem, so the main goal of public science popularization should be to introduce and promote synthetic biology, which is unfamiliar to them. However, after the survey, we were surprised to find that even the citizens of Hangzhou, who are well educated and live in a province with well-developed printing and dyeing industry, know little about the pollution problem from printing and dyeing industry and its potential threat to the environment. Therefore, popularizing relevant knowledge has become an important part of our activities in the following educational work.

Team:Worldshaper-XSHS/Human Practice