Comprehensive emergy evaluation and optimization of corn straw power generation system: a case study

ABSTRACT

Biomass energy has become an important measure to alleviate ecological environment security and energy supply security in China. Emergy accounting method is used to analyze and evaluate economy, environment, and sustainability of corn straw generation system, which includes corn planting subsystem, collection and transportation subsystem, and corn straw power generation subsystem. The key substances that need to be optimized in the system are identified by using sensitivity analysis. Based on the position of key substances in the system, emergy accounting optimization methodology is conducted. Corresponding optimization design scheme is proposed based on the “3R” (reduce, reuse, and recycle) principle of circular economy. Current study shows that emergy yield ratio, emergy investment ratio, environmental loading ratio, and emergy sustainability index of the corn straw power generation system are 3.69, 2.68, 1.61, and 2.29, respectively, which are better than wind power generation system and thermal power generation system. In addition, it is proposed that the fertilizer alternative plan and the transportation redesign plan can replace 50,000 tons potash and reduce equipment resources by 20% and energy resources input by 30%. Economy and sustainable development of the system is significantly improved. The optimization design method based on the “3R“ principle proposed in this paper can provide a useful reference for the research in the field of resource recycling.

KEYWORDS:

• Emergy analysis
• sensitivity analysis
• sustainable development
• resource design

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes

1. $ means US dollars (US$).

Additional information

Funding

This research is supported by National Key R&D Plan [grant number 2016YFC0502805], China Major Science and Technology Program for Water Pollution Control and Treatment [grant number 2017ZX07101003], Shandong Provincial Key R&D Plan [grant number 2018GSF121005], and The Fundamental Research Fund of Shandong University [grant number 2018JC049].