Study On China’s Natural Gas Safety Evaluation And Early Warning System

Natural gas has been known as the twenty-first Century’s energy because of its cleanness, low pollution, many countries have regarded natural gas as the preferred fuel, and plans to gradually increase its proportion of the possession in energy consumption. According to the "BP World Energy Statistics2012", until the end of2011, the global consumption of natural gas was amounted to3.2trillion cubic meters, representing an increase of2.2%over2010,while the Middle East has the fastest growth of natural gas consumption,6.9%.. In future, Natural gas as a clean energy, will continue to play an important role in the new energy era with environmental problems have become increasingly severe. According to the International Energy Agency, whether in the existing policy unchanged or increased greenhouse gas emissions control stimulus policy, by2030, natural gas will become the only energy of fossil fuels with growing demand. The market demand of natural gas in China is increasingly vigorous, even lead to economic decline rapidly, energy supply and demand significantly decreased in the world under the influence of the financial crisis, China’s natural gas consumption is still maintained two-digit growth.However, China is the country of " lack of petroleum and natural gas ", by the end of2011, China’s natural gas proven reserves of3.1cubic meters, accounting for the world total proven reserves1.5%, reserve and production ratio is29.8years, far below the world average of63.6years; at the same time, natural gas consumption in China ranks the4th in the world, increasing21.5%compared to2010, which cause the widening gap between China’s natural gas supply and demand and the foreign dependency rate increasing year by year. the gap of natural gas supply and demand of China in2011has reached28.2billion cubic meters. In addition, according to the relevant experts’ estimation by2015China will have more than30%of the natural gas dependence on foreign imports. However, the formation of the China’s gas price" cost plus method " is still in the planned economy period, the residents to use gas as welfare and the price is relatively low, leading to price upside down, making foreign gas having no advantage in price competition, only to withdraw from Chinese market. This kind of price distortions with a rapid expansion of shortage between demand and supply, makes residents having no consciousness of saving natural gas resources because of its low prices; and causes the "gas shortage" because the market is not standardized.This means that there are many problems in the storage quantity, supply capacity, market regulation of China’s natural gas industry and safety problems of natural gas resources has become a major strategic issue in China’s economic development and social stability, how to natural gas resources in China’s security situation evaluation and detailed, comprehensive, and based on the analysis of natural gas safety early warning, monitoring and early warning systems to establish reasonable evaluation, are important measures to promote China’s economic development, social progress, military and diplomatic security, more is to safeguard China’s energy security and healthy development of the key.This thesis firstly analyzes the key factors affecting the safety of natural gas, according to the evaluation index and the establishment of natural gas safety early warning index system; followed by the prediction of impact assessment index of gas safety, gas safety level in future, and evaluate the security status of the development of early warning for natural gas safety warning system, early warning signs reveal the formation of unsafe factors, for the safety of natural gas prevention and to provide basis for decision making and control.By the systematic research, the main results are as follows:1.with summarizing the domestic and foreign scholars’ researches of oil security early warning, this thesis conducts a research of early warning of natural gas safety in China, natural gas safety early warning indicators were selected according to the constructing principle of early warning system, established the gas safety early warning evaluation index system, the weights of the indexes by analytic hierarchy process, and based on the evaluation of the early warning index, analysis of the safety status of safety situation and the early warning of natural gas in our country the next few years,.2. Through the collection of2007-2011years of relevant data of China’s natural gas safety early warning indicators, according to different characteristics of early warning indicators and the difficulty of predicting using ARIMA-AR-VAR-GM (1,1) model, Curve regression method, Elamn neural network respectively to each index of natural gas in our country security early warning index system respectively forecast, and on the results of the analysis, the reliability of the method is verified and the data is accurate.3. Using AHP-GRA-TOPSIS method to evaluate the safety of natural gas in China at present and the warning of the safety of natural gas development trend of the coming period. The method comprises the following steps:(1) the analytic hierarchy process to calculate the comprehensive evaluation index weights;(2) by comparing the data with method of grey correlation analysis to determine the geometry similarity relation is close, so as to determine the degree of correlation between samples (scheme);(3) the TOPSIS method can determine the positive ideal indexes value and the negative ideal value, the close degree of each scheme and optimum scheme is given, the ranking of the alternatives. Therefore, using the index weight with AHP and grey correlation degree based on improved TOPSIS distance and Euclid distance of the multiple attribute decision making method, can make full use of their respective advantages, give more reasonable evaluation results.4. On the basis of natural gas security early warning index system, the natural gas safety evaluation and early warning software was established, which solves the problems of large input amount of information data of natural gas safety warning. its proneness to errors and poor operability, reducing the labor intensity and is convenient for all kinds of safety information management and early warning. index of each factors, influence the software of the natural gas safety trend monitoring and prediction, and forecast the current situation and future trends of natural gas safety.5. To put forward the countermeasures and suggestions of how to guarantee the safety of China’s natural gas.