1. Regulatory requirements

1. Country <: Air pollution prevention law > Article 44: Operators of urban catering services must take measures to prevent and control the pollution caused by oil fumes to the living environment of nearby residents.

2 Measures for Beijing to implement the Law of the People's Republic of China on the Prevention and Control of Air Pollution:

Article 32 Operators of catering services must take measures to prevent and control oil fume pollution, and the oil fume pollutants discharged shall not exceed the prescribed emission standards.

The bottom floor of residential buildings will no longer be provided with catering service establishments that produce oil smoke pollution; Residential buildings in residential buildings shall not be used as places of business for catering services that produce oil fume pollution.

if the pollution in the existing catering service business premises disturbs people, it shall be rectified or closed down within a time limit.

Examination and approval of environmental protection for construction projects in Beijing:

5. Catering projects:

(1) Meet the basic requirements of construction projects;

(2) It is not allowed to set up catering business premises that produce oil fume and odor pollution on the ground floor of residential buildings and in residential buildings;

(3) The stove must use clean fuel such as gas or electric energy, and the boiler must also use clean fuel such as gas or electric energy in the high pollution fuel no-burn zone;

(4) devices for collecting and processing oil fume and odor must be set up and discharged through special chimneys, and the height of the special chimneys should be higher than the residential buildings within 21 meters around;

(5) measures should be taken to prevent and control noise and thermal pollution caused by installing air conditioners and exhaust devices; Air conditioners and exhaust devices shall not be set near residents' windows, and shall not directly face sidewalks on both sides of commercial pedestrian streets and main streets. Noise reduction and sound insulation measures shall be taken to meet the noise standards of local fixed noise sources at the factory boundary;

(6) The wastewater should be treated by oil separation or residue filtration and then discharged into the municipal pipe network; If there is no municipal pipe network around, the wastewater should be treated to meet the corresponding discharge standards before discharge. Residues and wastes generated in the course of operation shall not be discharged into sewers.

People's Government of Xicheng District, Beijing:

With the development of regional economy and the adjustment of industrial structure, the proportion of tertiary industry in Xicheng District is increasing, the number of catering industry is increasing year by year, and the discharge of oily sewage from catering industry is increasing gradually. In order to further strengthen the management of grease wastewater discharge from catering industry, make the treatment of grease wastewater less, harmless, resource-based and market-oriented, put an end to illegal recycling of gutter oil, prevent municipal pipelines from being blocked, and protect people's health, recently, Xicheng District Municipal Management Committee and District Environmental Protection Bureau jointly issued the Notice on Strengthening the Management of Grease Wastewater Discharge from Catering Industry to the resident units, requiring the resident catering industry and unit canteens to: 1. Consciously abide by relevant laws and regulations on environmental protection, and improve their health. 2. Install effective oil separation facilities, and recycle the separated oil by qualified professional recycling enterprises regularly according to the design requirements; 3, according to the requirements of the notice, arrange self-examination, timely rectification.

the district municipal management Committee and the environmental protection bureau will conduct a comprehensive inspection of the catering industry and unit canteens according to the requirements of relevant laws and regulations, and punish the catering enterprises that fail to install effective oil separation facilities according to the regulations, resulting in excessive discharge, and record them in the warning information system of enterprise credit information in Xicheng District for announcement.

3. In the "Nanjing Air Pollution Prevention and Control Bill", the environmental protection requirements of the catering industry are clearly defined, and the catering operators are required to abide by the following provisions:

Clean energy must be used, and oil fume shall not be discharged into sewer pipes; A fume purification device should be set up to ensure its normal operation, so as to achieve the standard discharge. If the discharged pollutants exceed the standard, the professional operation unit of pollution control should be entrusted to maintain the operation; Set up a special flue for catering industry, and the height and position of the flue outlet shall not affect the surrounding living and working environment.

The draft also proposes that anyone who violates these regulations will be fined up to 21,111 yuan.

1. Current situation of pollution discharge of catering industry in this city

In recent years, with the continuous advancement of urbanization and the continuous adjustment of industrial structure in Shanghai, all kinds of production enterprises, especially polluting enterprises, have moved out of the city one after another, and the tertiary industry has developed rapidly. A large number of hotels, restaurants, amusement places, large shopping centers, standardized vegetable markets and other catering service facilities have been built, which has played a positive role in prospering social economy, enriching people's material and cultural life, and broadening employment. However, the oily wastewater, lampblack and noise it discharges do have a certain impact on the surrounding local environment. Services such as catering and entertainment have gradually become the main pollution sources in the urban area except domestic pollution sources, and the pollution disputes caused by them have become increasingly prominent.

taking Changning district as an example, there are 755 registered restaurants, of which 35 are operated by foreign investors, and 215 are large restaurants with more than 511 seats. The daily discharge of catering wastewater is 146,111 tons, which exceeds the total amount of wastewater discharged by industrial enterprises in Changning district.

Although the amount of wastewater from catering service industry is not very large, the concentrations of pollutants such as suspended solids (SS), animal and vegetable oils and CODcr are high, especially suspended solids and animal and vegetable oils will cause local sewers to be easily blocked, and the load of urban drainage pumping stations will increase. According to the regulations of environmental protection, all registered restaurants should be equipped with oil-water separation devices before opening, and oily wastewater will be discharged to the urban sewage pipe network after oil-water separation. However, because some projects are limited by the site, investment funds, operating costs and so on, they lack suitable oil separation facilities and long-term management during operation, so the treatment effect is very poor.

It is found in the survey that some restaurants have never lifted the lid of the grease trap since they opened, which has not really played the role of oil separation and degreasing. For example, there are more than 61 large and small restaurants along Xianxia Road in Changning District. In August 2111, the environmental monitoring station of the district monitored and analyzed the catering wastewater discharged by 21 restaurants. The results showed that according to the three-level discharge standard of Shanghai Integrated Wastewater Discharge Standard (DB31/199-1997), the CODcr exceeded the standard in 17 restaurants, and the rate of exceeding the standard reached 85%. 14 BOD5 companies exceeded the standard, and the rate of exceeding the standard reached 71%; 4 NH3-N exceeded the standard, and the rate of exceeding the standard reached 21%. SS exceeded the standard by 3 companies, and the rate of exceeding the standard was 1.5%. The situation in other districts is basically the same.

at present, most of the treatment methods of oily wastewater in restaurants are to build new multi-bin oil separation equipment. From the experimental results of oil-water separation, the longer the residence time of oily wastewater from restaurants in static oil separation equipment, the better the effect of separating floating oil from water. Usually, after a residence time of 45 minutes, the oil removal effect is generally over 71%. If some technical measures are added, the oil removal efficiency can be further improved.

2. Suggestions on controlling and reducing the discharge of sewage and oil from catering industry

In view of the problems existing in the treatment of oily wastewater from catering industry in Shanghai and the treatment of oily wastewater, the following suggestions are put forward:

1. Suggested revision of standards: It is suggested to revise Shanghai Comprehensive Wastewater Discharge Standard DB31/199- 1997 and

Water Quality Standard for Sewage Discharged into Combined Pipelines DBJ18. In view of the fact that almost all catering industries have exceeded the standard at present, it shows that this standard is debatable (Shanghai Water Affairs Bureau has also organized experts to discuss it many times). In fact, CODcr and BOD5 are the most serious indicators of oily wastewater in catering industries. After these indicators enter the sewage treatment plant through the drainage pipe network, it is not a problem to treat them at all. If they are mixed with industrial wastewater, it will be beneficial to the subsequent biochemical treatment.

Therefore, it is suggested to relax the requirements for CODcr and BOD5 indicators in Shanghai Comprehensive Wastewater Discharge Standard and Water Quality Standard for Sewage Discharging into Combined Pipelines, and resolutely implement the standards for animal and vegetable oils ≤111mg/L and SS ≤ 211 mg/L..

2. It is suggested to strengthen administrative supervision: on the premise that there are laws to follow, further strengthen the inspection of environmental protection and water law enforcement in Shanghai. Carefully verify the displacement of oily wastewater from restaurants at the peak, so as to determine the volume and size of the oil separation equipment, and ensure that the retention time of oily wastewater in the oil separation equipment should not be less than 45 minutes, and the removal rate of floating oil should reach more than 71%; At the same time, restaurants that discharge excessive wastewater should be forced to levy excessive sewage charges.

3. It is suggested that the layout should be further reasonable: the catering industry should be properly controlled in the process of urban development, and the location of newly-built catering industry should be relatively concentrated, so as to facilitate centralized treatment of catering wastewater, meet the discharge standards and reduce the pollution to the surrounding environment. Catering industry should focus on the overall planning and layout of the city, set aside space and location suitable for the development of catering industry, and strictly control the establishment of catering industry in residential areas.

4. It is suggested to adopt technical means to reduce emissions: for restaurants of different sizes and locations, different treatment technologies for oily wastewater from restaurants can be selected.

(1) Small and medium-sized restaurants (with less than 211 seats) with daily discharge of oily wastewater from restaurants should be equipped with multi-bin grease traps with sufficient capacity, supplemented by oil-absorbing felt or biological filter elements for further treatment, so as to strengthen daily oil skimming and cleaning, and strive to achieve the discharge standard of catering wastewater.

(2) For a large-scale restaurant (with more than 51m3 seats) with a daily discharge of oily wastewater, it may be considered to separate the oil through multi-bin oil separation equipment first, and then remove a large amount of organic matter and grease from the wastewater through dosing or biological treatment, so as to ensure that all indicators meet the discharge standards.

(3) For a large-scale dining street or a super-large restaurant, a centralized wastewater treatment station should be built for a large-scale restaurant with a daily discharge of oily wastewater of more than 211m3 (with more than 2,111 seats), and the wastewater from each restaurant should be preliminarily separated from oil, and then collected together for treatment, so as to ensure that the oily wastewater reaches the standard after treatment.

5. It is suggested to enhance publicity: through publicity and education, the general public and catering industry should be made aware of the dangers of oily wastewater from restaurants.

(1) Provide guidance to catering practitioners through industry associations and government window departments to ensure that all catering industries are equipped with matching oil separation equipment, and at the same time, provide maintenance training for maintenance personnel to ensure that the oil separation equipment is maintained normally, which has achieved due results.

(2) When appropriate, people can be guided to pay attention to the oil-water separation and waste oil collection in family kitchens, reduce pipeline blockage, and reasonably recycle resources. In today's rising oil prices, waste oil from restaurants is the best raw material for biodiesel.