Risk Dynamic Evaluation System Study Of Environmental Protection PPP Project Based On The Improved System Dynamics

In recent years,the problem of air pollution in beijing-tianjin-hebei region,has been into the eyes of the people again and again.While the human beings are panicking about their own health,the environmental protection has become an unavoidable issue.The sixth plenary session of the 18 th CPC central committee advocated "integrating the construction of ecological civilization into the whole process of economic construction,political construction,cultural construction and social construction".The environmental protection department of the People's Republic of China has also called for that we would continue to improve the quality of the environment and strive to build a beautiful China with blue sky,green land and clean water.Thus,the construction of environmental projects not only affects the environment itself,but also involves the development of national economy and the great progress of society.It is no delay.However,China's economy is at an important stage of new normal,with features such as slowing growth rate,structural optimization and transformation and upgrading.But the financial burden of debt which some local governments in our country have has been a serious situation,even at the fringes of the government's limit,Environmental protection is an indispensable part of the process of the sustainable development in our country,and the conflict btween the pressure of local government debt and the economic development needs in the field of environmental protection which maintains a moderate investment scale at the same time has become more and more prominent.The application of the PPP financing mode can effectively solve the above problems.To avoid the risk of the PPP financing mode is the key to the success of the project.As the PPP financing model gradually rises in the developed countries such as the UK,our country started late,and the PPP financing mode must combine with the China's specific national conditions So,the using of the PPP financing mode in the field of environmental protection is not very mature.The research of the risk evaluation is relatively small.Although some achievements have been made,there is still a great lack of evaluation methods.This paper attempts to construct an environmentally friendly PPP project risk assessment system by the method of the improved system dynamics based on thelife-cycle Angle of the environmental PPP project risk identification(dynamic).The whole evaluation process can be divided into three stages: risk collation,risk relationship establishment,and key risk factors output.(1)Risk consolidation stage: the risk factors of the environmental protection PPP project in the whole life cycle are preliminarily sorted out by means of risk checking and reference,etc.The risk factors are dynamically reduced by rough set and the risk factors are divided into key risk factors and boundary risk factors.(2)The establishment stage of risk relationship: Firstly,establish and arrange the risk causal loop chart of environmental protection PPP project,and it will improve the fitting capacity of the model;Then,the risk inventory flow chart of environmental PPP project is established based on the causal loop,and the accumulation effect and change rate of each variable in the system are clarified;Finally,the boundary risk factors were evaluated by the entropy weight method and the G1 method.(3)The output stage of the key risk factors: the assignment of boundary risk factors and the relationship between the key risk factors are put in the software of Vensim-PLE to obtain the key risk simulation analysis results;The results are summarized in the Radar map which includes the five stages of the total life cycle,and the main risk factors of each stage are obtained.This article selects the sewage treatment project which the Qingdao-veolia everbright has operated as an example.Using the above risk evaluation model has proved that this evaluation system is scientific and reasonable,and it provides a reference for the risk assessment of environmental PPP projects in the whole life cycle.The corresponding measures should be taken to deal with the main risk factors which has been identified above.