The massive discharge of pig farming wastewater poses a significant threat to the ecological environment.According to different treatment processes,pig farming wastewater treatment methods mainly include ecological treatment,industrial treatment,and centralized treatment.The industrially treated sewage is directly discharged into natural water bodies.However,there is a greater risk of environmental pollution,so the realization of high-efficiency water quality monitoring for pig farming sewage under the industrial treatment model can bring great convenience to ecological protection.At present,the water quality monitoring of pig farming sewage still has problems such as low water quality index detection efficiency,high cost,and single water quality evaluation method.In response to these problems,this paper proposes a high-efficiency and low-cost detection method for the water quality of pig breeding wastewater and a comprehensive water quality evaluation method to achieve agile monitoring.The main contents of this article include:(1)Conducting a study on the correlation between the water quality indicators of pig farming wastewater and finding that there is a strong correlation between NH3-N(ammonia nitrogen),TN(total nitrogen),and EC(electrical conductivity),providing a theoretical basis for alternative detection methods of water quality indicators.(2)Regression analysis and modeling with NH3-N,TN,and EC as objects,successfully established a simple regression model,combined model,comprehensive model,and compared and verified,and finally constructed a low-cost measurement model of the optimal pig sewage water quality index.(3)Based on the water quality index’s evaluation method,each water quality index is standardized and weighted,and the water quality index of pig farming wastewater is calculated.Then combined with the stepwise multiple linear regression method and the water quality index alternative detection method to screen the key indicators,the conductivity and chemistry are determined.Determined the EC and COD(chemical oxygen demand)as key indicators,and finally build a minimum water quality evaluation model.This paper proposes a high-efficiency and low-cost detection method for the water quality of pig farming wastewater.It determines a"polynomial regression model"suitable for NH3-N and a"comprehensive model"of TN.After verification,the two models’coefficients are as high as 0.855and 0.953,respectively.It is well used to evaluate NH3-N and TN’s concentration in pig breeding sewage;the minimum water quality index model established based on EC and COD,its determination coefficient,and the residual square sum is 0.997 and 0.86,respectively.The verification results show that the similarity between the water quality results judged by the minimum water quality index model and the water quality judgment results based on the five leading indicators can reach 85%,which provides an essential theoretical basis for establishing the agile pig breeding wastewater monitoring program.This paper has the following two innovations:(1)The method of correlation analysis is used to establish a high-precision regression model between NH3-N,TN,and EC,and the use of EC(low detection cost)to replace the detection of NH3-N and TN(high detection cost)rapid and low-cost water quality detection;(2)Combining the alternative detection method proposed in this article with the stepwise multiple linear regression analysis methods,selecting critical indicators for the construction of the minimum water quality index evaluation model,and realizing the quality of pig sewage Efficient and fast evaluation. |