China Water Supply and Drainage Design Experience Liu Qixiang, Chen Hua (Liyuan Water Supply Design Consulting Company, Shenzhen 518031, Guangdong) Design of Pipeline Direct Drinking Water in Shenzhen Meilin First Village And experience. Meilin Yicun residential area is developed and constructed by Shenzhen Housing Bureau. It covers an area of ​​about 44X104m2. It plans to build 65 multi-storey houses and 31 middle-to-high-rise houses, with a total of more than 7000 households and plans to occupy about 30,000 people. 1 Introduction to Design 1. Water quota and water consumption For buildings in different regions and of different natures, the drinking water quota is different, and the country has not made clear regulations on the drinking water quota for residential buildings. According to relevant data, about 0.5% to 2% of the urban water supply is used for cooking and drinking. At the same time, the drinking water standard for pipeline direct drinking water in other domestic cities is set as: q = 5L / (person.d) direct drinking water Quantity: The average day is Q-level = 150m3 / d, the highest day is Q-high = kdQ-level = 1.3X 150 = 195m3 / d Community direct drinking water system water supply design scale: Q = 200m3 / d high day-to-day variation coefficient: d = 1.2 Treatment process Water purification treatment process flow The treatment process fully compares several membrane filtration technologies such as microfiltration, ultrafiltration and reverse osmosis to determine the use of ultrafiltration. Ultrafiltration can not only remove residual organic matter and harmful substances in tap water, but also retain trace elements beneficial to human body in water, which is also the difference between high-quality drinking water and pure water. Each treatment process is designed according to the highest daily average flow rate, and based on the characteristics of the system allowing intermittent water supply, the treatment process adopts a single group design. 1.3 System Design See system design process. System design flow This system adopts centralized processing, unified water supply by pipeline, and establishes a water purification station in the community. According to the different water pressure required by the user, the quality of water supply is implemented while considering the water supply of the partial pressure system. Through comparison of energy consumption, cost, operation management and other aspects, the direct drinking water in the community is divided into three independent water supply pipe network systems: multi-layer system, mid-rise system and high-rise system. In order to protect the water quality, the entire system is not provided with secondary pollution water tanks and water tanks, etc., from production to delivery are fully enclosed design, and like the hot water supply system is designed with a circulating pipe network system, to further ensure that users use water Safe and reliable, high quality, this is also the most prominent feature of the design of direct drinking water system. 1. Pipe network design The designed direct drinking water is only for drinking water. Each household only considers installing a drinking faucet in the kitchen. The indoor and outdoor pipes are calculated and checked according to the design second flow rate and maximum flow rate respectively. While following the design specifications of the water supply pipeline, the pipeline network is arranged according to the principle of striving for shortness and straightness, simplicity and smoothness, and coordination with other pipelines. Under the premise of safety and reliability, accessories that have secondary pollution such as accessories and interfaces are minimized In particular, the remote metering water meter is adopted to minimize the length of the branch pipe entering the household after the water meter, to ensure thorough circulation, and to fully guarantee the water quality. In view of the special nature of direct drinking water, in order to ensure that the water quality remains unchanged during the transmission process, in addition to setting the transmission pipeline system to a fully enclosed circulation type, higher requirements are also placed on the material of the pipeline. After comprehensive comparison, the following pipes were selected in this project. Outdoor pipe: PVC-U pipe for circulation pipe and multi-layer system; domestic stainless indoor pipe for middle-high layer and high-rise system: Aluminum-plastic composite pipe for multi-layer system and circulation pipe; middle-high-rise and high-rise system and circulation pipe Imported thin-walled stainless steel tube. 1.5 Circulation system design The design of the circulation system is the biggest feature of the direct drinking water design, and it is also the most fundamental difference from the design of the tap water supply system. According to the characteristics of direct drinking water, after full discussion and certification by experts, it is believed that to meet the requirements of water quality standards, the system must be designed to be circular. The design of the direct drinking water system uses two sets of circulating pipe networks, that is, the multi-layer system sets the circulating pipe network separately, and the middle and high-rise systems jointly set the circulating pipe network. The two circulating pipe networks are independent of each other and do not interfere with each other. , Forming a small circulation system or called a sub-circulation system (see). The circulating water volume is designed according to 50% of the total water volume of the pipe network, that is to ensure that the user's water is produced within 12h (except the water in the branch pipe after the water meter). 1.6 System operation management System operation management mainly includes the management of water purification stations and water supply pipeline networks. The water purification system implements linkage control of effluent water quality, water quantity and water pressure, and is fully automated. The operation and management of the water supply network is mainly for the operation management of the circulation system for ensuring water quality. Since the circulation system is composed of grouped sub-circulation systems, the system does not have to implement 24h circulation throughout the day, but is determined according to the water quality of the drinking faucet. The operation rule of the circulation, the time and quantitative circulation of the sub-circulation system is carried out in batches to achieve the principle that the drinking water meets the standard, which is also the characteristic of the operation of the circulation system. 2 Design Discussion 21 As a new type of water supply developed in China in recent years, direct drinking water in the water quota pipe network, the water quota used in the system design is usually taken as q = (person.d). This quota is too small for Shenzhen. Due to the high annual temperature in the southern region, and with the further improvement of citizens' living standards, high-quality water will be used not only for drinking and cooking, but also for rice washing, vegetable washing, and even beauty. Therefore, it is more appropriate to set a direct drinking water rating of 8 ~ 10 "(person d) in Shenzhen, which is only 5% ~ 7% of the actual household water consumption, which is more in line with the actual situation; from a planning perspective, it is also only About 2% to 4% of the residents' domestic water consumption, compared with 0.5% to 2% of the urban water supply used for cooking and drinking, is also more in line. Therefore, according to the local environment and climate, we should formulate it in line with the actual situation of each place The situation of direct drinking water quota. 22 Regarding the system scale, the amount of direct drinking water in the pipeline is small, and the system scale is generally small. Therefore, in addition to considering the technical factors, the operation management and economic feasibility of the system are particularly prominent. Medium and large residential communities with relatively concentrated dwellings and a large number of households are conducive to the implementation of piped drinking water. On the contrary, the implementation of direct drinking water in residential areas with scattered residential areas and fewer residents will greatly increase the cost of unit aquatic products and management and operation costs, and will inevitably reduce Business Benefits. Therefore, the author believes that communities with less than 1,000 households should not use pipes to directly drink water, otherwise the cost of drinking water will be too high. 23 Scope of quality water supply At present, the pipeline quality supply in some urban residential areas in China is to separate the direct drinking water in domestic water. After deep treatment, another system is set up for residents to drink and cook. This type of quality water supply system Water consumption and scale are generally small, and there are limitations in the implementation process. The author believes that the range of quality water supply should be expanded, that is, to separate domestic drinking water from domestic water. The specific design is to implement quality water supply for kitchens and toilets, so as to implement quality water supply in a broad sense, which is conducive to the implementation of quality water supply system It is helpful to reduce the cost of the system, especially the tap water system before the separate water supply, and facilitate the operation and management of the system. The main thing is to greatly reduce the cost of the unit water production of direct drinking water and make the direct drinking water system more economical. Rationality and implementation feasibility. 3 Concluding remarks The direct drinking water at the exhibition stage is an example. The various types of "water" on the market not only change people's drinking water concepts, but also impact traditional tap water. Although China's drinking water quality standards still have a large gap compared with developed countries, first of all, it should be fully affirmed that any tap water that has undergone strict inspection and meets the national drinking water quality standards is drinkable, and with the development of the economy, China's drinking water quality standards will continue to increase. As far as the current situation is concerned, it is unrealistic to substantially improve the tap water quality of the entire city to meet the requirements of the direct drinking water quality standard. Therefore, the secondary purification of tap water can be implemented in areas where economic conditions permit, forming a community Separate quality water supply system, locally improve the drinking water quality of residents, as a transitional measure to improve the quality of tap water, which also meets the residents' demand for high-quality drinking water, and its water quality standards, water supply systems, pipe selection, design parameters All will be summarized in practice. Progress of Qingdao Municipal Wastewater Recycling and Reuse Qingdao City is one of the nation's severely water-stressed cities. Per capita water consumption, China's average per capita water is only 2,500m3 per year, which is only one quarter of the world's per capita water. The per capita occupancy is 375m3, which is less than one sixth of the national per capita water. Since the Yellow River and Yellow River Diversion Project was put into operation, Qingdao's water supply has eased. However, with the development of industrial and agricultural production and the improvement of people's living standards, the water consumption continues to increase. With the continuous extension of the Yellow River's outage period, the shortage of water resources has become a problem that cannot be ignored. In 2000, the water supply and demand can still be balanced, but by 2010, there will still be a serious crisis in urban water supply. Therefore, while saving water, it is necessary to establish a water-saving economy, actively develop and use other water resources, and vigorously promote the recycling of sewage, which is much more economically reasonable than the vast South-to-North Water Diversion Project and seawater desalination project. After implementing the pilot project of modular sewage treatment in Fuzhou Road District of Qingdao City, part of the sewage was reused, and the green area in the irrigation area was 311m3 / d. The annual water saving can be 20.5X 104m3. Qingdao Haibohe Wastewater Treatment Plant In February 1999, a sewage reuse project with a scale of 4X 104m3 / d was completed (the secondary treated effluent was used as the influent water source of the sewage reuse project), and it is currently operating in good condition for 13 within 3.5km of the lower Haibo River The water used by enterprises, stadiums and the Haibo River landscape can save 1,104m3 of water resources every year. The pre-feasibility study report of the wastewater reuse project of Huangdao Economic and Technological Development Zone has been completed, and the construction of Nibuwan Wastewater Treatment Plant in the development zone has been started. The treatment scale is 3.5X 104m3 / d in the near term and 7X104m3 / d in the long term. X104m3 / d long-term treatment scale 5X104m3 / d reclaimed water is mainly used in factories and enterprises in the development zone, and a small amount is used for landscaping. In the near future, it can save tap water annually 912.5X1 (fm3, long-term can save tap water 1 1 (fm3. The price is calculated at 1 yuan / m3, and the price of tap water is calculated at 1.80 yuan / m3. In the near future, funds can be saved by 7.3 million yuan per year, and in the long-term, funds can be saved by 14.6 million yuan per year. In terms of economic benefits, the cost of producing water in an industrial water purification plant that uses sewage as raw water is lower or even much lower than that of a water plant that uses natural water as raw water. This is because it saves water resources fees, water intake and long-distance water delivery. Energy consumption and construction costs. The water treatment cost of Haibohe Sewage Treatment Plant and Huangdao Economic Development Zone is much cheaper than the price of tap water. If the tap water currently used for spraying green areas and pavement flushing in Qingdao is replaced with reclaimed water, significant economic benefits can be obtained. (Contributed by Wang Yemin, Qingdao Ocean Design Institute, Liu Li, Qingdao Municipal Design and Research Institute) we are mascara brush factory,all mascara brush types we can custom,such as thin mascara brush ,disposable brush ,small mascara brush ,mini mascara brush ,double mascara brush.you can use mascara brush to brush mascara eyebrow eyelash,or use for eyelash extension.we also can private label with mascara brush for you Disposable Mascara Brush,Small Mascara Brush,Mascara Spoolie,Mascara Wand,Mascara Applicator,Mascara Comb,Mascara Brushes Shenzhen Nanfang Shishang Cosmetic Utensil Co., Ltd. , https://www.nfbrush.com