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1 Kazuhiro Shida Kansai International Airport Co., Ltd. 1.Global warming issue The crisis of global warming on a global scale is increasing. The promise period to reduce greenhouse gas under the Kyoto Protocol has started in Many countries including Japan are required to accelerate the effort. The cause of global warming is due to an imbalance of heat balance on earth induced by excessive carbon dioxide (hereinafter referred to as CO2 ). At the Kansai international airport approximately 75% of CO2 is emitted from the aircraft and accounts for a large percentage of the total, compared to CO2 emissions from airport facilities. Hence, it is necessary to strive to reduce CO2 emissions from the aircraft. 2.Waste issue To create a recycling-oriented society, waste reduction, waste reuse and waste recycling are important. Although the Kansai international airport is in an advanced position in terms of waste handling and takes a responsibility to handle the waste issue, it has still a few issues to cope with. To reduce high volume industrial waste as well as general waste is also important. Hence, it is recommended to tackle the rest of the waste issues. 3.Water issue Water on earth is approximately 1400 million km3. However, most of the water is seawater. Fresh water is 2.5% of the total and the majority of fresh water is the Antarctic and Arctic ice. The river water and lake water to use for drinking is actually 0.01% of the total. In that sense water resources are extremely valuable. Hence, in a situation where fresh water is running out, it is evident that what we should do at the Kansai international airport is to reduce the consumption of fresh water regarding water saving. 4.Eco-friendly material It goes without saying that it is preferable to use eco-friendly materials from an environmental point of view, when it comes to constructing airport facilities and installing airport devices. In that case it is not always necessary to employ state-of-art materials and with-it materials. It seems that there are eco-friendly materials regardless of being old-fashioned. 5.Environmental strategies at airports With the aim of becoming the eco-lovely island (eco-friendly airport) the Kansai international airport has formulated the eco-lovely island plan for five years until 2012 and established 44 numerical targets. Hereunder, focusing on the global warming issue, waste issue and water issue in case of the Kansai international airport, I would like to ponder clues and new ways to solve environmental challenges in the short run or long run and to propose some strategies. 1

2 6.Airfield emission reduction (1)Ground Power Unit (hereinafter referred to as GPU ) An aircraft has an auxiliary power unit (hereinafter referred to as APU ) running with aviation fuel which can supply electricity and air conditioning to the aircraft while parking at airports. Although APU is very convenient, it generates a considerable amount of noise and CO2 resulting in global warming. Meanwhile, instead of APU there is GPU to supply electricity and air conditioning to parked aircraft. Since electricity is supplied from electricity power companies in case of GPU, it is more efficient. As shown in Figure 1 and Table 1, GPU does not cause noise and results in a dramatic drop in CO2 emissions. GPU is absolutely an effective way to reduce the issue of noise and global warming. Figure 1 CO2 emissions [Comparison between APU and GPU] Table 1 Noise [Comparison between APU and GPU] Noise source Noise value(db) Distance from source APU(B747) GPU 92 Impossible to obtain 20m 10m (2)Analysis of issue Currently except Kansai international airport and Narita international airport regarding the use of APU there are no regulations in particular at most of airports in Japan. Using APU depends upon the airlines and there are significant differences among the airlines as shown in Figure 2. Due to rising oil price as well as regulations stipulated in 2003 at the Kansai international airport, many foreign airlines have increased the use of GPU. However, the fact remains that some of airlines has started switching over from GPU to APU in accordance with the recent decline in oil prices. After all even if GPU is installed at airports, in essence the main point is how to improve the GPU utilization. 2

3 Figure 2 GPU utilization status at the Kansai international airport (3)Consideration 1Modification of supply system Since electric power cables, air conditioning pipes and pits for GPU are buried at the apron in terms of GPU s construction methods, construction costs are higher in Japan. By and large in case of many Japan's airports including the Kansai international airport, an administrator of passenger boarding bridges (hereinafter referred to as PBB ) is different from an administrator of GPU. However, as shown in Figure 3, if they construct PBB and GPU jointly and hang power cables and air conditioning pipes on PBB, the supply system will turn out to be cost-effective and GPU fee will be eventually reasonable. Figure 3 Example of supply system 2Energy conservation With regard to supply system for electricity, the existing system of rotating power supply unit should be changed to the stationary power supply unit which is cost-effective in terms of utility cost and maintenance cost. This electric power consumption will be approximately one-fifth for energy conservation. 3Burden of cost At the Kansai international airport, looking at the way many foreign airlines do not use GPU, the 3

4 reason is because a combination of APU maintenance cost and aviation fuel cost is paid by the headquarters of foreign airlines. On the other hand airport branch offices in their management have a tendency to use not GPU, but APU even if GPU is more cost-effective than APU. It is necessary to provide sufficient explanation to foreign airlines to induce them to use GPU vigorously. (4)Strategy In the future in case of constructing new spots administrators of GPU and PBB should be in cooperation and install their facilities with hanging power cables and air conditioning pipes on PBB to reduce the initial cost of GPU. With regard to the power supply facilities, stationary power supply systems should be adopted for energy conservation. On top of that it is necessary to explain that GPU is advantageous total cost-wise and to promote the use of GPU to airlines by having a heart-to-heart talk one way or another. 7.Industrial waste reduction (1)Filter-separator element for aviation fuel The amount of industrial waste and general waste is approximately 460 million tons annually in Japan. Since especially the amount of industrial waste is approximately 90% of the total, it is important to reduce the amount of industrial waste. As shown in Figure 4, at the aircraft refueling facility of the Kansai international airport aviation fuel unloaded from oil tankers is transferred to storage tanks. Then, aviation fuel is pumped to aircraft at the aprons via hydrant pipelines. In that process water and dust contained in aviation fuel is removed by receiving filter-separator elements and delivering filter-separator elements. In this way clean aviation fuel is supplied to aircraft via hydrant pipelines. In the maintenance management differential pressure of a filter-separator element is monitored daily and the inspection is performed after one month, one year and two year from the replacement of a filter-separator element. Three years later a filter-separator element is replaced by a new one again. As a result of that, the fact remains that many filter-separator elements are discarded as industrial waste so far. Incidentally the specification of a filter-separator element must be in accordance with American Petroleum Institute. Also, there are very few manufacturers in the world. Figure4 Flow chart of aircraft refueling facility (2)Analysis of issue The rule of exchanging a filter-separator element is mainly based on the joint guidelines which are 4

5 established by a consortium of major oil companies in the world. Taking account of the joint guidelines, a filter-separator element is supposed to be exchanged mostly in case of reaching 100 kpa or at interval of three years in Japan. Consistently a filter-separator element has been exchanged in Japan for well over 30 years in accordance with these conditions (in a way practices). However, at the time of exchange it turns out that differential pressure does not reach 100 kpa at all and reaches only kpa which ranges from one-fifth to one-third of exchanging standard. The reason is because aviation fuel from oil refineries and oil depots is carried in clean condition and aviation fuel is kept under a strict quality control in storage tanks at airport of final destination. In addition to that, since aviation fuel in clean conditions is delivered to aircraft, a filter-separator element is kept in good condition just like a new one. (3) Consideration It is impossible to make an experiment in order to know the time of reaching 100 kpa without exchanging a filter-separator element using the existing facility after three years of operation. Hence, I decided to predict the time to reach 100 kpa with the least squares method mathematically. (Please see Figure5-6) As a result of that, it turns out that several years are needed to reach 100 kpa. Namely it is possible to prolong the life of a filter-separator element for a period of several years and to reduce the disposal of industrial waste. Eventually the cost of airport operation can be reduced as well... Figure 5 Receiving filter-separator element Figure 6 Delivering filter-separator element 5

6 (4)Strategy Since aircraft refueling facilities in the world are in operation on a basis of the joint guidelines or consistent practices, and mostly airlines adhere to them, the Kansai international airport in Japan alone cannot change the rule of exchanging a filter-separator element in a short period. Hence, in the first place it is necessary to ask for a cooperation of Petroleum Association of Japan. Then, we have to work on oil companies in Japan. By the same token it is important to get a handle on working on explaining the necessity for the revision of rule or practice to airlines coming to the Kansai international airport in order to inspect the operation of the aircraft refueling facility. We have to make it a worldwide movement in order to reduce industrial waste. 8.Industrial waste reduction (part2) (1)Oil fence at tanker pier At oil tanker piers of the Kansai international airport oil tankers are surrounded by oil fence in order to prevent a marine pollution due to leakage of aviation fuel during unloading aviation fuel from oil tankers. Figure7 Layout of oil tanker piers at the Kansai international airport (2)Analysis of issue Since oil fence is prominently damaged by the influence of waves force, oil fence for more than 1000m is replaced by a new one every year. Lots of stryrofoam which became useless were generated as industrial waste. (3)Effect 1Volume reduction The shortcoming of styrofoam is too bulky to handle. Once the volume of styrofoam is reduced, it becomes easier to store and transport. 6

7 2Recycling Until several years ago all of styrofoam was discarded as industrial waste. However, after starting using the machine which melts styrofoam to foam a dense block of material with a thermal treatment to reduce volume, the volume of styrofoam was reduced to approximately one-tenth. We made it possible to recycle styrofoam successfully. The cost of the machine is the same as the expense of annual industrial waste treatment. On assumption that it is possible to use the machine for ten years, the expense of annual industrial waste treatment becomes one-tenth. Recycled styrofoam is taken by dealers and is used as materials plastic. (4)Strategy We succeeded in reducing the expense of industrial waste treatment as well as the volume. Henceforward, it is recommended to use the machine in order to reduce industrial waste if Styrofoam is generated in other places at airports. 9.Waste reuse (1)Wastewater treatment facility At the Kansai international airport there is a wastewater treatment facility in which the method of denitrification and nitrification processes with activated sludge is adopted. The facility includes a feedback pipe for circulating wastewater from the nitrification tank to the denitrification tank. As shown in Table 2, it is also designed to highly process wastewater and significantly to reduce levels of nitrogen and phosphorus with the aim of mitigating the eutrophication in Osaka bay forming a closed sea-area. Table 2 Wastewater quality discharged Monitoring item Criteria BOD Not more than 10 mg/l CODMN Not more than 15 mg/l SS Not more than 15 mg/l NITROGEN(N) Not more than 15 mg/l PHOSPHORUS(P) Not more than 1 mg/l (2)Analysis of issue Figure 8 illustrates a flow chart of wastewater treatment facility at present. With regard to the current wastewater treatment, a combination of the denitrification tank and the nitrification tank is needed in the aeration tank. It is in the nitrification tank that a nitrate-nitrogen is generated and is removed to the denitrification tank by the feedback pipe. On the other hand it is in the denitrification tank that a nitrogen is completely removed into the atmosphere. Wastewater is biologically processed in the aeration tank. Then, the suspended solids settle down in the settling tank. With regard to the sludge sediment, a part of sludge sediment is reused as return sludge (activated sludge) circulating around the aeration tank for a biological process. Then, in the 7

8 flocculating tank Poly Aluminum Chloride (hereinafter referred to as PAC ) is injected for chemical processing. Usually the suspended solids with less than 10 μm perform the Brownian motion and do not precipitate by gravity at all. Since the suspended solids are electrically negative-charged(-30mv) and repulsive each other, it is very difficult to form a flock and the suspended solids are divergent in the water. PAC converts -30mV into ±10mV and eliminates the repulsive force. Moreover, polymer flocculant plays a supplementary role in combining a small flock and a small flock in the flocculating tank. The rest of sludge sediment is incinerated as waste sludge. Finally the upper part of clean water in the flocculating tank is discharged. The issue is that an expensive PAC and polymer flocculant captured by sludge is eventually incinerated with extra-sludge. Figure 8 Flow chart of wastewater treatment facility at present (3)Consideration 1Reuse of PAC As shown in Figure 9, at the flow of wastewater treatment process in case that PAC is injected in the last part of aeration tank instead of the flocculating tank, most of PAC may be reused with the return sludge. Figure 9 Flow chart of wastewater treatment facility in case of improvement 2Reduction of polymer flocculant In case of injecting PAC in the aeration tank, it is possible to reduce the polymer flocculant in the flocculating tank by using sticky properties of activated sludge in the aeration tank. 3Energy conservation 8

9 In case that the amount of sediment is significantly reduced in the flocculating tank, it is possible to stop the running of rolling machineries in the flocculating tank and conserve energy. (4)Strategy Since temperature change may have an impact on the ability of the new way, it is necessary to make an experiment to confirm the effect for several months. As mentioned above, the method of experiment is to inject PAC in the aeration tank and return sludge with PAC is circulated. In accordance with flocculating status, the amount of PAC injected is to be reduced gradually. After that, we will confirm each flocculating status and treatment status. On assumption that water quality is stable, we plan to stop the running of rolling machineries and injecting PAC as well as polymer flocculant in the flocculating tank. 10.Waste recycling (1)Waste treatment facility In the clean-center of the Kansai international airport there are incinerators which burn waste from aircraft and airport facilities and sludge from wastewater treatment facility, recycling sorting facility, recyclable yard to recycle waste. There are two incinerators with a capacity of 60 tons/24hours for garbage incineration and one of them is always in 24 hours operation. Now taking the amount of waste into account, each incinerator plays a part and is in operation at interval of five weeks. One incinerator is supposed to be out of operation on Saturday and in operation on Sunday. (2)Analysis of issue As shown in Table 3, in terms of the amount of waste, waste generated from aircraft accounts for approximately 20% of the total and ranks first among various waste. Waste generated from in-flight food factory ranks second. The issue is that waste from aircraft is gathered in a mixed state without sorting, compared to other waste except for a few airlines. Then, it is transported to the clean-center and incinerated there. Table 3 Waste categories in 2007 at the Kansai international airport Waste categories Rate (%) Waste generated from aircraft Waste from in-flight food factory Burnable Sludge Mowed lawn Corrugated cardboard Unburnable 20% 19% 19% 14% 7% 7% 4% (3)Consideration 9

10 Figure 10 shows that the recycling rate is approximately 9% of the total amount of waste. On assumption that it is possible to recycle approximately 50% of waste generated from aircraft, there is a possibility that the recycling rate jumps from 9% to around 20%. Figure 10 Recycling status at the Kansai international airport (4)Strategy It is preferable to install a recycling facility in which waste generated from aircraft is sorted by hand or using a machinery. However, since there is a possibility that the cost of sorting rises, it is necessary to explain the importance of sorting and get airlines consent. By the same token, it is necessary to cooperate with airlines and to come to terms with them in order to deal with procedure for customs and quarantine. 11.Tap water reduction (1)Tap water supply facility There are two water lines regarding water supply at the Kansai international airport. For one thing there is a tap water line for the purpose of drinking and washing. For another thing there is a recycled water line for the purpose of flushing in toilets and watering lawns and trees. Tap water is supplied from Izumisano city and wastewater is highly processed in the wastewater treatment center and is reused as recycled water at the Kansai international airport. (2)Analysis of issue 1Large amount of water use The amount of water used at the Kansai international airport is approximately one million tons per year. In terms of the water consumption, the district heating and cooling plant (hereinafter referred to as DHC ) ranks first because of the method of evaporative cooling towers using tap water. The 10

11 DHC was constructed to make use of energy efficiently and reduce air pollution. However, it uses approximately 30% of the total tap water as shown in Table 4. Table4 Consumption of tap water in 2007 Airport facility Annual consumption(ton) Supply pump center DHC Passenger terminal building Hotel In-flight food factory Energy center Warehouse of cargo Station, parking lots 1050 thousand(total) 300 thousand 230 thousand 130 thousand 110 thousand 20 thousand 17 thousand 16 thousand 2Global warming Evaporative cooling towers are installed for heat-exchanging at the DHC as shown in Figure 11. The exhaust heat is emitted from evaporative cooling towers in the atmosphere as latent heat. Latent heat in the atmosphere has an effect contributing to global warming just like CO2. Figure11 Method of evaporative cooling towers using tap water (3)Consideration 1Unused energy As shown in Figure 12, there is an unused energy making use of a difference of temperature between the seawater and the atmosphere effectively for the purpose of heat-exchanging. Since the Kansai international airport is located on the sea, it is preferable to take advantage of its location. On assumption that the method of using seawater as unused energy is adopted instead of evaporative cooling towers, various benefits may come into existence. 2Tap water reduction Since a large quantity of tap water is evaporated by evaporative cooling towers, the amount of 300 thousand tons of tap water is greatly reduced to almost nothing by using seawater. 11

12 Figure12 Method of using seawater as unused energy 3Global warming restraint Although the exhaust heat is somewhat emitted in the atmosphere through the surface of the sea, the influence to the atmosphere is restrained to a large extent. In addition to that, since the temperature of seawater is lower than the temperature of atmosphere, the DHC itself can be highly improved in summer with respect to efficiency. In general the energy consumption to produce tap water for a quantity of ten thousand tons is equivalent to 46 hundred kwh in terms of electric power conversion. In case of reducing 300 thousand tons of tap water, the electric power of kWh can be reduced to nothing annually. Namely unused energy can contribute to promoting a effective use of water resources and the reduction of environmental burden to generate electricity(50000 kg-co2/year). (4)Strategy On assumption that it is possible to take advantage of location close to sea and river at the time of replacing evaporative cooling towers, or constructing a new DHC in the future, it is recommended to make use of unused energy in order to reduce a large quantity of tap water consumption at airports. 12.Eco-friendly material (1)Water tank Currently it is possible to drink tap water without boiling in Japan. In spite of that, some people prefer to drink mineral water, taking account of a healthful aspect. However, surprisingly enough the price of mineral water in Japan is approximately 1300 times as expensive as that of tap water. In that sense it is necessary to pay attention to materials and maintenance for tap water tanks in order to supply tap water in good condition to those who are health-conscious. (2)Analysis of issue 1FRP-made water tank FRP-made panel is damaged by ultraviolet rays and its glass textile is exposed to outside. In case of FRP-made water tank which is installed outside, the water-proof rubber between frame and FRP-made panel is damaged by aging. 12

13 2SUS-made water tank In case of SUS-made panel since the thermal conductivity is very large, condensation appears on the surface of the panel by an environmental condition. 3Other Since mineral water is filled in a plastic bottle, many wastes are generated. (3)Consideration Tap water tanks have been made of FRP, SUS and so forth for a long time. However, it is necessary to focus on a wood from an environmental point of view regardless of being old-fashioned. Japan has a history of using a wooden vessel to store water, boiled water, sake(japanese alcohol) and soy sauce in the daily life for well over 1000 years. Most people have a reliability and a safety toward a wooden vessel. Apart from Japan, many wooden tap water tanks have been used in New York city for a long time. 1Characteristics of material In general a wood is eco-friendly, anti-bacterial, water resistant, anti-acid, and anti-alkaline. 2Healthful management Thermal conductivity of wood is 0.13 kcal/m h. For example compared to metal, it is approximately 1/300. It has an excellent thermal retention. The temperature of tap water is kept constant and the water is well-tasted. For reference, former Ministry of Health and Welfare in Japan stipulated standards for delicious water in 1980s. Among standards, delicious water s temperature is recommended to be constantly kept at less than 20. On top of that, since condensation does not appear, any dust is not attached to the surface of tap water tank. It is possible to realize a healthful management. On the other hand in case of installing a tank outside, since ultraviolet rays do not go through wood, algae in the tank do not appear with a certain thickness of wood. 3Reduction of plastic bottle On assumption that tap water becomes healthful and delicious, some people may switch over from drinking mineral water to drinking tap water. It will result in reduction of plastic bottles. 4Recycling At the time of replacing, it is possible to recycle used woods as recycled papers, wood chips. (4)Strategy As mentioned above, a wooden tap water tank is transcending in many aspects. Recently many wooden tap water tanks have been employed in places such as Kyoto state guest house, prestigious hotels, food manufacturers, hospitals and so forth in Japan. Hence, it is recommended to consider employing a wooden tap tank at the time of replacing or newly-constructing at airport as well. 13. Conclusion With regard to environmental challenges, many airports must be in confrontation with great concern, that is to say, once airports grow up, not only energy consumption, but also environmental challenges are on the increase. However, it is supposed that it becomes possible to realize managing airport 13

14 operations to meet environmental challenges by having a questioning mind and struggling to find out new ways with good ideas and reasonable investments. Thereby, we will win public applause in the world. Finally I would like to express my thanks to you for reading my research paper. Kazuhiro Shida working for KIAC since