Recovery And Economic Effect Evaluation Of Construction And Demolition Waste Under Different Recovery Costs

With the acceleration of my country’s urbanization process and the improvement of people’s living standards,the construction industry is also developing rapidly.At the same time,it has also brought a series of social problems,and the resource environment is also undertaking enormous pressure.With such a huge amount of construction and demolition waste,the ability to recycle and reuse is seriously insufficient.Meanwhile,the government has also implemented relevant policies and measures to encourage and promote the recycling and green development of construction and demolition waste.Through research,it is found that the unit recovery cost of construction and demolition waste is much greater than the unit landfill cost.For the construction side,they are more willing to choose to landfill construction and demolition waste instead of recovery,resulting in unsatisfactory construction and demolition waste recovery effect.Therefore,by adjusting the unit recovery cost,this paper studies the relationship of the cost between the construction side and the recycler side to improve the recovery effect of construction and demolition waste.And together,it is necessary to verify the feasibility of adjusting the unit recovery cost in terms of economic effect.Based on the above background,this paper firstly clarifies the relationship between the relevant subjects in the construction and demolition waste recovery process on the basis of literature research,and finds out the main factors of the construction and demolition waste recovery process and determines the relevant parameters and variables,so as to lays a background and logical foundation for the subsequent modeling.Secondly,based on the theory and method of system dynamics,a construction and demolition waste recovery and economic effect evaluation model is constructed,including a construction and demolition waste recovery effect evaluation subsystem and a construction and demolition waste economic effect evaluation subsystem,then a causal cycle diagram and a stock flow diagram are respectively constructed to perform qualitative and quantitative analysis of the model.Finally,based on the investigation of the construction and demolition waste recycling market in Beijing,this paper firstly predicts the generation of construction and demolition waste in Beijing from 2021 to 2029 by combining the building area estimation method and the grey model.Then use three methods: data collection method,expert interview method and system dynamics unique table function to determine the value of each parameter and variable in the model.And simulation analysis of the construction and demolition waste recovery and economic effect evaluation model was performed.After passing the model test,the parameters are brought into the model for simulation,and when the actual unit recovery cost is 65 yuan / ton,the simulation results of the recovery rate,the sorting ratio,the recovery ratio,the costs and benefits of all parties are in line with the actual situation.Finally,the results of the construction and demolition waste recovery rate,sorting ratio,recovery ratio,costs and benefits of all parties are simulated under the scenarios where the unit recycling cost is adjusted to 45,25,5,and-5 yuan/ton,and the conclusion is drawn:(1)With the reduction of unit recovery cost,the waste recovery rate has increased.When the unit recovery cost is 5yuan/ton,the waste recovery rate is expected to exceed 30% by 2029.(2)With the reduction of unit recovery cost,the ratio of sorting and recovery is increasing.(3)With the reduction of the unit recovery cost,the decrease of the total cost of the construction side is greater than that of the total income of the recycler side,indicating that the reduction of the unit recovery cost is economically feasible.Therefore,it is suggested that the government should gradually reduce the unit recovery cost of construction and demolition waste,and change the current mode that the construction side pays waste recovery fees to the recycler side into the mode that the recycler side purchases construction and demolition waste from the construction side through market and policy means.Economically,not only the cost of the whole society will be saved,but also the development of the overall production level of the recycling industry can be promoted;in the environment,the pollution of construction and demolition waste to the environment can also be reduced.