An Industrial Symbiosis Evaluation On The Ecological Industrial Park In The Ulan Buhe Desert

At present,desertification has become one of the most serious environmental problems in the world.It has become a great threat to human existence and has caused serious impacts on regional economic development and social stability.Since Mr.Qian Xuesen put forward the scientific concept of sand industry,many scholars have conducted studies on sand industry and large numbers of research achievements have been achieved.However,there are few studies on ecological industrial parks（EIPs）or industrial symbiosis（IS）evaluation related to sand industries in China,and the current situation of the industrial symbiosis in sand industrial parks remains unknown.Therefore,this research took the EIP in the Ulan Buhe Desert as the research object to conduct an IS evaluation based on the field investigation of ecological industry in sand areas.An IS evaluation indicator system suitable for EIPs in sand areas was constructed to quantify and assess the IS level of the case park by applying four comprehensive indicators,including eco-efficiency,IS indicator,eco-connectance of EIP,and,byproduct and waste recycling rate of EIP.The results showed that:（1）In terms of eco-efficiency,the output value of raw material consumption,water consumption,waste water emissions and solid waste emissions per unit of the EIP in the Ulan Buhe Desert present 5.23×10~4,8.3×10~3,9.03×10~5and 5.96×10~6yuan/t respectively,which are significantly higher than the average level of Jiufa EIP and of the whole country.The output value of energy consumption per unit is 6.6×10~3yuan/t,which is slightly lower than the average level of Jiufa EIP and of the whole country,this is mainly due to high power consumption of each production link in each symbiotic unit in the case park and the high diesel consumption in the planting stage.The output value of unit exhaust gas emission is8.03×10~5yuan/t,which is slightly higher than the national average level;（2）Benefited from the recycling of by-products between planting and breeding in the park,the case park has a better performance in IS indicator and eco-connectance of EIP,which are 1.16 and 0.309,respectively.The IS indicator of the case park is 1.29times of an EIP in Brazil,and the eco-connectance of EIP is higher than that of Kalenburg,Guigang and Lubei EIPs;（3）The byproduct and waste recycling rate of EIP is pretty low,only 2.28%.This is mainly due to the large emissions of CO₂,CH₄,N₂O and other waste gases generated by diesel combustion in mechanical operations and wastewater from various processing links of the enterprise,which account for49.41%and 43.93%of the total waste emissions in the park,respectively.These wastes are directly discharged into the environment after treatment without recycling.At the same time,as an organic fertilizer recycled to the planting stage,the amount of recycled excrement only accounts for 55.54%of the total excrement emissions,and44.46%of the excrement is not able to be recycled.To improve the IS level of the case park,suggestions were further put forward,including improving the reuse rate of water resources,applying clean energy and enriching industrial types,so as to promote the industrial structure optimization and increase economic and environmental benefits.Above all,this research explored the IS level and existing problems of the EIP in Ulan Buhe Desert and developed corresponding suggestions for improvement.This study can provide theoretical and technical support for further optimization research of the case park and other related parks,and thus provide reference for promoting layout optimization and sustainable development of sand industries.