Hua Yan Water (China) Co. Ltd.: Opening new thoughts of energy saving and consumption reduction with ＂five major efforts＂

Company profile
 
Hua Yan Water is a water business brand operated by Hong Kong and China Gas Co., Ltd. (hereinafter referred to as Towngas) in Chinese mainland. Towngas started to participate in the construction and management of urban public utilities in Chinese mainland in 1994. Hua Yan Water, a subsidiary company of Towngas sought business collaboration with pipeline gas and opened the mainland water market in 2005. It has invested 7 water projects successively in Wujiang District, Suzhou, Jiangsu province, Wuhu in Anhui province, Suzhou industrial park in Jiangsu province, Zhengpu Port New District in Maanshan, Anhui province, and Jiangbei industry zone in Anhui province. Its business scope covers tap water production and distribution, sewage treatment, industrial wastewater treatment, middle-water reuse, pipe network construction, and pure water production and marketing.
 
By the end of April 2018, Hua Yan Water had constructed and operated 10 modern water plants and served more than 1.2 million households. The total length of its pipe network has exceeded 7900 kilometers, having a daily water supply capacity of more than 2.5 million tons, a daily sewage treatment capacity of 370,000 tons, and a daily middle-water reuse capacity of nearly 40,000 tons, which provides high-quality life and industrial water for the economic development of mainland cities.
 
Challenges
 
Water is the source of human survival and development. The continuous development of the industrial economy increases the water consumption in China, and also brings about the increasingly prominent water waste. It is said that only the water loss from pipeline will result in more than 7 billion cubic meters of tap water loss per year, which is equivalent to a Taihu Lake in one year and the total water volume is enough for the water use of 100 million urban residents. Therefore, water plants in various places have renovated the water supply system to reduce energy consumption. However, in the production process, many water plants are still suffering from the energy loss due to lack of technologies such as emission reduction and comprehensive treatment, and the production costs remain high.
 
As a water company, Hua Yan Water has attached great importance to its environmental impact for many years. Hua Yan Water has always regarded environmental sustainability as an important issue. How to further reduce energy consumption, pollution emissions, environmental pressure, and effectively reduce water supply costs through technological transformation and management is also a serious challenge for Hua Yan Water.
 
Solutions
 
Hua Yan Water continues to explore and research new methods and ideas to save energy and reduce consumption, rationally use water resources, and guide and appeal to the whole society to pay attention to and protect water resources, and to help customers, communities and cities to achieve sustainable use of water resources, forming an environmental competitiveness with Hua Yan characteristics .
 
Since 2016, focusing on energy saving and consumption reduction, Hua Yan Water has conducted method research from 5 aspects, namely accurate measurement of water flow and fine control of water quality, energy consumption monitoring of key equipment and improving energy efficiency, water supply system energy consumption and distribution balance and control, energy leakage consumption and equipment selection optimization, application of new technology and equipment and monetization evaluation, and built the data analysis method based on "five major efforts". It has taken a series of measures, like installing electric meters and importing the information electronically into the report, to ensure the timeliness and accuracy of data acquisition. Then, the company carried out field tests and validations and found out some "short boards" which are extremely energy-consuming and energy-saving restrictive.
 
Balancing and controlling water supply system energy consumption and distribution
 
Taking Yangcheng lake water plant and Xingang street water plant as examples, the company has compared their production and operation records. The water withdrawal electricity consumption of Xingang street water plant is related to the water withdrawal quantity. The larger the water withdrawal, the higher the water withdrawal electricity consumption. As the water withdrawal is under 270,000 tons per day, the water withdrawal electricity consumption is relatively low. The integrated unit water supply consumption of Yangcheng lake water plant is about 18% lower than that of Xingang street water plant. Therefore, under the circumstance that the two plants supply water at the same time and the pressure of municipal pipe network is durable, it can reduce integrated energy consumption of the two plants by satisfying the 150,000-ton water supply per day of Yangcheng lake water plant first and then the lower water supply of Xingang street water plant.
 
Monitoring energy consumption of key equipment and improving equipment performance
 
The key is to strengthen energy consumption monitoring and ensure the efficient operation of pumps. In addition, the pump units consume a lot of electricity during the production process of the water plant. The main reason lies in the rapid growth of water supply quantity and the rapid transformation of water supply network. However, the water pump units of the water plant did not carry out synchronous transformation in time, which lowered the efficiency of the water pumps and led to the waste of a large amount of electricity. Measures like comprehensive maintenance of water distribution pumps, pump housing repair, positioning shaft updating, and impeller balance correction were taken to improve the efficiency of water pumps. The efficiency of pumps is significantly improved after the comprehensive maintenance.
 
Abandoning high energy-consuming products and updating equipment
 
To reduce energy consumption of water production and comprehensively improve the quality of urban drinking water, the water plant has carried out a large-scale scrapping of high energy-consuming products, updated and renovated equipment, and selected advanced on-line water quality instruments and other modern production testing methods to strengthen the whole-process inspection and control of water quality. The company's production and management personnel can receive the pressure situation of water supply pipe network anywhere through the system, and its water supply pipe network is connected with Suzhou Water Company, Kunshan water Company, Wuzhong Water Supply Company to ensure standby and safe water supply in emergency.
 
Besides, Hua Yan Water has replaced the previous static mixers with high-efficient static mixers and analyzed energy saving effect comprehensively to reduce the head loss to 0.5-0.6m, reducing by 0.6-0.7m. It has reduced the total consumption of hydropower by 0.3% through optimizing process and improving the recovery and utilization of ozone cooling water. The company has optimized the structure of pipe network, distributed the pressure of pipe network and promoted the construction of pipe network, which reduced the total unit power consumption by 1%. It also implemented strict control of extra pressure and reasonable matching of pump units to stabilize pump flow and pressure.
 
Achievement
 
Social benefit
 
By the end of 2017, the power charge of Hua Yan Water was reduced by 8.68% compared to 2015 when energy-saving renovation was not carried out, saving 29.88 million kwhs of power on a year-on-year base. From the perspective of low-carbon and environmental protection, it is equivalent to saving 9611 tons of coal for thermal power generation, and reducing carbon dioxide emissions by 29,700 tons, saving about 21.02 million yuan in total. In addition to saving power consumption, the water quality indexes such as turbidity and COD of the produced water all decreased, and the quality of customer service was further improved. The energy saving method can also be generalized to other high energy-consuming enterprises.
 
Economic benefit
 
Through unremitting efforts, a number of energy-saving renovation measures taken by Hua Yan Water were put into operation, and the power consumption was significantly improved compared to before, which reduced the production and operation costs and improved the company's competitiveness and popularity. Hua Wan Water was awarded "2016 Advanced Unit for Safety Management of Hazardous Chemicals in Suzhou". Its three projects, "reducing unit electricity consumption of water supply", "shortening water sample test time of Xinggang street water plant" and "reducing the failure rate of secondary water supply pump room equipment", were awarded Excellent SQS Project Prize and Excellent Contribution Award of Hong Kong and China group, the honorary title of "Suzhou Taihu Water Source and Drinking Water Safety Engineering Technology Research Center" and "2017 Five-star Chinese Excellent Enterprise Citizen ", respectively.
 
Prospect
 
Hua Yan Water is not only an enterprising company, but also committed to protecting the environment and fulfilling corporate social responsibility. While improving customer satisfaction, it has increased the net profit of economic activities and contribute to the environment protection by reducing resource consumption, environmental degradation and pollution throughout the entire life cycle.  In the future, Hua Yan Water expects to promote the environmental protection and pursue green development through the joint efforts of the government, enterprises and the public while promoting the improvement of the quality of water supply services.