"The Five-Element Integrated Approach" targets the odor control in seven key areas
The following seven key areas - the northern part of the urban area, the Bridge Industrial Park in Nanhu District, the Tianning Town in Jiashan County, the Yucuohang Town in Xiuzhou District, the Dushan Port Area in Pinghu City, the Chemical Industrial Zone of Haiyan Economic Development Zone and the Port Chemical Industrial Zone - have always been the hotspots of public complaints and are also the key and difficult points of the "Five Air Pollutants Control" work in the city.
Yesterday afternoon, a site promotion meeting for the odor and exhaust gas control work in the key areas was held in Jiaxing Port Area. The meeting required the city to deeply implement the "Five Air Pollutants Control", coordinate the collection, treatment and management of the three links, take the elimination of odor pollution that has been strongly complained about by the public as a breakthrough point, and carry out the odor and exhaust gas control actions in key areas comprehensively. It is aimed to significantly improve the regional environmental air quality within about three years.
Odor and Exhaust Gas Control in Seven Key Areas
Focus on VOCs
In recent years, among the nearly 100,000 environmental complaint cases in the province each year, the odor problem accounted for nearly 60%. In 2016, the odor-related complaints in our city accounted for 64% of the environmental complaint cases, and the odor-related complaints in the city's environmental complaints involving the seven key areas accounted for 72%.
The most frequent complaints from the public about the air pollution in the seven key areas are about the unorganized emission of odors from enterprises. And this odor comes from the volatile organic compounds (VOCs) in the exhaust gas.
In the past three years of the "Five Air Pollutants Control" work, our city mainly focused on the control of PM2.5 pollution, strengthened the control of coal consumption总量， the elimination of small boilers， the ultra-low emission renovation of thermal power enterprises， the treatment of enterprises consuming over 10，000 tons of coal， and the elimination of yellow-label vehicles. The concentration of PM2.5 has decreased significantly. However， the ozone concentration in the city's environmental air quality remains high and even shows an upward trend. Ozone has replaced PM2.5 as the primary pollutant affecting the excellent rate of the city's environmental air quality. And VOCs are an important precursor to ozone formation and is a "blocker" that restricts the further improvement of the air quality excellent rate in our city.
"Full sealing" and "Full covering" of odor generation links
Volatile organic compounds (VOCs)， as the name suggests， are volatile and unorganized emissions of gases. In the process of its treatment， the collection of exhaust gas becomes the top priority of the treatment.
To promote the odor control work of enterprises in the seven key areas， our city issued the "Implementation Plan for Odor and Exhaust Gas Control Actions in Key Areas of Jiaxing"， clearly stating that through the promotion of "Full Sealing" projects， the collection rate of process odor and exhaust gas should be improved； the "Full Covering" project should be implemented to reduce the emission rate of odors from wastewater and waste liquid； the "Full Collection" system should be established to increase the collection rate of odor and exhaust gas； the "Full Treatment" requirements should be implemented to improve the removal rate of odor and exhaust gas； and the "Full Supervision" ability should be enhanced to reflect the treatment effect realistically. Among them， to prevent the emission of exhaust gas during production， the production workshops， raw material warehouses and production lines should be sealed； for the sewage treatment facilities and the main odor generation links， full covering should be implemented， and the odor and exhaust gas from production processes and storage tanks should be fully collected， and the leakage repair of outdoor transportation pipelines should be done well.
Yesterday， the participants visited the exhaust gas treatment projects of Pinghu Proportional Packaging Co.， Ltd. and Jiarun New Materials Co.， Ltd. in Jiaxing Port Area. Pinghu Proportional Packaging Co.， Ltd. has achieved full sealing of the production workshop， full collection of production exhaust gas， and full treatment of production exhaust gas.
"To ensure the full collection of organic exhaust gas， our production workshop adopts the full sealing method. We use aluminum alloy to separate the production workshop from the pedestrian passage. Workers can only enter and exit the workshop through three doors. One door is for entering and exiting through the wind shower room， and the other two cargo passages use two quick doors and a wind membrane device to prevent the emission of exhaust gas. The workshop becomes a relatively sealed space." An employee of Pinghu Proportional Packaging Co.， Ltd. introduced.
The reporter witnessed the ingenious design of these two cargo passage doors in the company's workshop. The two doors are automatically opened and closed through electromagnetic induction. After a truck passes through one door, that door immediately closes, and the other door will only open after the first one has closed, ensuring that the exhaust gas does not escape.
The enterprise's waste gas collection process is divided into two parts. The first part covers the printing grinding discs on the printing machines, and the waste gas is collected uniformly through a self-modified collection system and sent to the VOCs treatment device. The second part collects the waste gas in the workshop through the pipes of the drying system and then sends it to the VOCs treatment device. The workshop is equipped with an automatic waste gas alarm system. If the waste gas concentration reaches the set value, it will automatically alarm.
To achieve full treatment of production waste gas, the enterprise added 4 sets of zeolite parallel devices and 1 set of desorption catalytic combustion device last year. The treatment process includes zeolite adsorption, heating desorption, and catalytic pyrolysis. The waste gas treatment rate has significantly improved.
This year, 20 demonstration enterprises will complete the rectification.
In the seven key areas, many enterprises ignore waste gas collection. The workshop is ventilated by opening windows, and most of the waste gas is diluted and discharged, while only a small amount of waste gas enters the treatment facilities for processing. This leads to a significant reduction in the treatment efficiency of the existing treatment facilities; many enterprises' storage tanks and wastewater treatment facilities do not have waste gas collection facilities, and the odorous waste gas spreads directly to the environment.
In the next three years, all key waste gas-emitting enterprises in the seven key areas must carry out VOCs rectification in accordance with the requirements of "full enclosure", "full covering", "full collection", "full treatment", and "full supervision".
At present, our city has listed a batch of key rectification enterprises in the seven key areas, such as He Xin Keli Li, Xiaoxing Amide Fiber, Chen Shang Auto Parts, Donghai Rubber, Xiaoxing Chemical Fiber, Han Tai Tire, He Xin Industry, Yong Xin Textile, Berlinton Textile, Dongming Stainless Steel and other companies in the northern area of the urban district. They have all been included in the rectification list. Among them, 20 demonstration enterprises for rectification will complete the rectification by 2017.
The "Implementation Plan for the Odor and Waste Gas Rectification Action in Key Areas of Jiaxing City" clearly states that in accordance with the new requirement of "the public cannot smell the odor and unpleasant smell", a comprehensive implementation of the odor and waste gas rectification in key areas will be carried out, achieving a "one-year improvement, three-year significant change" in regional environmental air quality. It is expected to use about three years to significantly improve regional environmental air quality, raise the regional environmental air treatment level to the forefront of the province, and strive to achieve "one improvement, two decreases, and three no-occurrences", significantly improving the satisfaction of the people, significantly reducing the number of complaints related to air pollution and the concentration of odor and waste gas pollutants.
