Microorganisms play a key role in dealing with volatile organic compounds

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This post was last edited by yinkuilin6868 on 2015-12-10 at 14:24. The Air Pollution Prevention and Control Law, known as the strictest air pollution law in history, will come into effect on January 1, 2016. According to experts, the new Air Pollution Control Law is more targeted and practical; it includes volatile organic compounds (VOCs) within its scope of regulation for the first time. While imposing constraints on enterprises, it also creates opportunities for the promotion of environmental protection technologies as well as for environmental technology companies. Guangdong Duncheng Environmental Protection Technology Co., Ltd. has been dedicated for many years to the research, development, and application of new technologies, new materials, and complete treatment systems for organic waste gas control. In recent years, the company’s “nebulized spraying + high-efficiency biological purifier” system, which uses the most efficient microbial purification method to remove and filter volatile organic compounds, has been well received by society. It is urgent to address volatile organic compounds. VOCs is the abbreviation for volatile organic compounds. It is understood that high concentrations of volatile organic compounds in indoor air can easily cause acute poisoning; mild cases may result in headaches, dizziness, coughing, nausea, vomiting, or a feeling of intoxication, while severe cases can lead to liver damage and even rapid coma, with some cases potentially being life-threatening. Living for long periods in indoor environments contaminated with volatile organic compounds can lead to chronic poisoning, and may even damage the liver and nervous system, causing symptoms such as general weakness, drowsiness, and skin itching. In some cases, it can also cause endocrine disorders and affect sexual function; benzene and xylene pose a risk of triggering leukemia as well. In recent years, Guangdong Province has launched vigorous efforts to control volatile organic compounds, covering 13 key industries such as oil refining and petrochemicals, manufacturing of chemical raw materials and products, production of active pharmaceutical ingredients, synthetic fiber manufacturing, surface coating, printing, shoe manufacturing, furniture production, wood-based panel manufacturing, electronic component production, textile dyeing and printing, plastic manufacturing and plastic products, as well as the service industry. Enterprises that fail to comply with relevant regulations, are unable to meet emission standards, or have idle treatment facilities are investigated and dealt with in accordance with the law. GAC Toyota, located on Huangpu Avenue in Tianhe District, Guangzhou, uses spray painting techniques during the surface coating process, and the paint contains benzene, toluene, xylene, and their derivatives. The workshops in enterprises that cause pollution include paint mixing rooms, painting booths, curing ovens, and intermediate coating workshops. During operations in these workshops, organic solvents evaporate, and their pungent odors pollute the surrounding environment. The existing facility for treating organic waste gases in this enterprise is a water spray tower; for organic solvents such as benzene that are insoluble in water, the removal efficiency of this water spray method is low, and it can easily cause secondary pollution to the surrounding environment. In response to this, GAC Toyota invited Guangdong Duncheng Environmental Protection Technology Co., Ltd. to use a \"nebulized spraying + high-efficiency biological purifier\" system (also known as a \"high-efficiency, low-resistance biological purifier\") to treat the organic solvent waste gases generated during rolling, oiling, and baking processes. Traditional methods can lead to secondary pollution. According to Zhan Shaojun, deputy general manager of Guangdong Duncheng Environmental Protection Technology Co., Ltd., activated carbon adsorption was commonly used in the past. The malodorous substances absorbed by activated carbon cannot be converted into non-toxic compounds, and they must be removed through regeneration. The activated carbon adsorption method presents problems such as complicated operation and management, high operating costs, difficulty in regeneration, and unstable purification effects, which can result in secondary pollution. High wind resistance and high energy consumption are also problems that are difficult to solve. It is understood that activated carbon adsorption requires frequent desorption; generally, it needs to be regenerated every month or so. Regenerating activated carbon necessitates a heat source for thermal desorption (such as a boiler or an electrically heated steam source) ； Furthermore, the organic waste gases released through the desorption of activated carbon must be treated using concentration — catalytic combustion or other processing methods; otherwise, secondary pollution will occur. As a result, the treatment facilities become more complex, with high costs in terms of investment and operation. Activated carbon continuously undergoes adsorption and desorption processes; it is prone to breaking, and each desorption cycle results in a gradual decline in its adsorption efficiency. As a result, the treatment effectiveness is unstable, and the breakdown of the activated carbon requires its complete replacement every few months. If the activated carbon disposal method is used without desorption, it is necessary to replace the expensive activated carbon frequently, which is not only troublesome but also results in higher economic costs. Due to the shortcomings of the activated carbon adsorption process, purification facilities often become unusable after a short time, and the pollution problem remains unresolved. Biological purifiers are more efficient and cost-effective. \"Highly efficient biological purifiers utilize microbial filtration technology to effectively treat and purify organic waste gases as well as eliminate unpleasant odors.\" Toxic and foul-smelling gases can have their odor removed within just a few seconds through our biological filtration system. The removal efficiency of organic solvents in exhaust gas can exceed 85%, the removal efficiency of toxic and malodorous substances can exceed 90%, and the removal rate of hydrogen sulfide in exhaust gas can reach 99.9%. The gas that has undergone efficient and rapid biological filtration is non-toxic and odorless, bringing significant benefits to factories, the atmospheric environment, as well as the lives and health of residents in the surrounding area. ”Zhan Shaojun, the deputy general manager, explained that a patent has been applied for this technology. In response, Manager He, the relevant official from GAC Toyota, said that with the use of high-efficiency biological purifiers, the odors emitted from the workshop are almost completely eliminated, making it more effective than the previous use of activated carbon for absorption. “We used to use activated carbon for adsorption, but the effect was not as significant as it is now. ”Manager He said that since the Tianhe District Environmental Protection Bureau is located next to the company, “the bureau stated that when we used activated carbon for odor removal, the smell was quite strong, and the related tests did not meet the standards. However, after using biological purifiers, the smell disappeared completely, and the tests were passed successfully.” ” Manager He told the reporter that they invested a total of about 900,000 yuan at one time in the new biological purifier. Previously, the cost of using activated carbon for cleaning and replacement on a monthly basis was around several thousand yuan. “Although the initial investment is higher now, in the long run it is still more cost-effective.” ”Manager He said that a favorable price isn’t the most important factor; what’s crucial is that the new air purifier enables the company to pass environmental protection assessments. “For a company, the cost is secondary – it’s important to avoid violations and to meet environmental standards.” ” On-site: Easy to operate, with no unpleasant odors after treatment. The reporter followed Deputy General Manager Zhan Shaojun up to the two-story-high platform to take a close look at the microbial purifier. “Firstly, microbial purifiers have a short treatment time and high efficiency. ”Zhan Shaojun, the deputy general manager, opened the exhaust outlet of the fan; when the reporter approached the outlet, they did not detect the pungent odor that volatile organic compounds should have. Deputy General Manager Zhan Shaojun opened the lid on top of the microbial purifier and explained the basic principle of the system by pointing to the tank filled with dark-colored water containing microorganisms. “We primarily use environmental bio-restoration techniques and biological filtration technologies to develop efficient biofilms for purifying and decomposing pollutants in exhaust gases. A “spray humidification + biological filter” system was designed. When malodorous waste gases containing a mixture of gas, liquid, and solid phases, as well as volatile organic compounds (VOCs), are introduced into this filter through dedicated pipes, the biofilm formed by special microorganisms cultivated within the microbial purifier comes into play. On one hand, this biofilm uses the pollutants present in the waste gases as nutrients for growth and reproduction; on the other hand, it biodegrades and deodorizes the odorous volatile organic substances (VOCs) present in the waste gases, converting them into non-toxic and odorless carbon dioxide (CO2) and water (H2O) before releasing them, thereby achieving the purpose of purifying the waste gases. ” The high-efficiency microbial purifier can convert volatile organic compounds in just 1.11 seconds. 2. Easy to maintain. Once the bio-bacteria form a biofilm in one step, no additional bio-bacteria are needed. Biological strains and fillers have a long service life, lasting over 10 years ； After 10 years, it can be reused through simple renewal. There is no need to regenerate it or replace it every one or two months, as is the case with activated carbon. 3. It is easy and stable to operate; apart from the fans required to collect and transport waste gas, the system incurs only electricity costs for the small water pump used for intermittent pumping of water for spraying, resulting in low power consumption. The operating costs are lower than those of other organic solvent waste gas purification technologies. Low pressure loss, resistant to clogging, and low failure rate (from fans and small water pumps). ” 4. It has the capability to operate intermittently. When the factory is under maintenance or closed, no maintenance is required ； After stopping operation for 30 days and running it again, the efficiency remains unaffected.