Assessment On Implementation Of Pollutants Emission Standard And Analysis Of Environmental Risk For Sulfuric Acid Industry

In recent years,the sulfuric acid industry has developed steadily under the standardized management of national environmental standards,meanwhile the emission of industrial pollutants has been reduced year by year,and the total amount effect of pollutant emission reduction was significant.Pollution emission standards are the basis for environmental law enforcement in China and an important means of environmental management.At present,the management of pollutant discharge standards has shifted from standard revision to standard revision,assessment on implementation,and publicity and training in China.Based on the background,the paper assessed the implementation of“Emission standard of pollutants for sulfuric acid industry”（GB 26132-2010）according to the relevant requirements of the national key research and development plan“The reason of air pollution control technology research”.At the same time,the air pollutant emission reduction potential and environmental risk of sulfuric acid industry were analyzed.Through industry research and literature review,the sulfuric acid industrial status was summarized,the development process of industrial pollutant emission standards was sorted out.And it was analyzed compared with the foreign sulfuric acid industrial emission standards implemented.According to the“The guidelines of assessment on implementation for national pollutants emission standards（trial）”,the analysis focused on the implementation of“Sulfuric Acid Industrial Pollutant Emission Standards”（GB 26132-2010）,including the standard compliance,the environmental benefits,economic benefits and social benefits obtained by implementation.the emission reduction potential of sulfur dioxide（SO₂）from the sulfuric acid industry was analyzed,and the various factors affecting SO₂emissions from the industry were quantified.Meanwhile,according to the current situation of the surveyed enterprises,the risk sources were analyzed and environmental risk prevention measures are proposed.The results of the study were as follows:（1）Advanced analysis of GB 26132-2010.Since the implementation of the“Discharge and emission standards of three industrial wastes（for trial implementation）”（GB J4-73）,the content of emission standards implemented by the sulfuric acid industry had become more detailed and scientific.GB 26132-2010had stricter limits and stricter requirements than previously implemented standards,and had added special emission limits for the first time.Compared with the foreign industrial emission standards,the pollutants emission limits of GB 26132-2010were much lower than these in the other countries.（2）Assessment analysis of the implementation of GB 26132-2010.Through investigation and study,it was found that the pollution-emission behaviors of all enterprises surveyed meet the requirements of emission standards,the compliance was close to 100%.The production process of sulfuric acid is more and more mature,double conversion/double absorption and end treatment processes are widely used.It was found that the production operations and equipment replacement costs required due to the implementation of the standard were completely within the acceptable range of the enterprise through cost-benefit analysis,and bring considerable economic benefits to the industry by reducing sewage charges and selling end processing by-products.The standard had achieved good emission reduction effects on pollutants emitted for producing acid from sulfur and pyrite.The COD emission reduction was nearly 2,000 t,and the SO₂emission reduction was about 40,000 t in 2017 compared with these in 2010.The implementation of the standard also drived the employment related environmental governance.The monitoring method for sulfuric acid mist needed to be further improved to meet the application requirements of GB 26132-2010.At the same time,the standard still needed to be further revised and optimized to adapte to the development requirements of the new era.（3）Analysis of SO₂ emission reduction potential from the sulfuric acid industry.Based on LMDI model,the specific conditions of the whole sulfuric acid industry（including producing acid from smelter flue gas）had been analyzed.Since the implementation of GB 26132-2010,the end treatment effect was the main factor to promote emission reduction,followed by production technology effect.On the contrary,economic effect basically promoted the emisssions of pollutants,but the impact of structural effects was relatively small.In particular,compared with 2010,the emission reduction contributed by treatment effect and technical effect in 2017 were 54,000 t and 15,000 t,respectively.At present,the actual SO₂emission concentration of the most enterprises was lower than the emission limit,and the average daily emission concentration of the more than 60%enterprises surveyed was lower than 200 mg/m³.The industry still had certain SO₂ emission reduction potential.（4）Environmental risk analysis of sulfuric acid industry.Based on“Environmental risk assessment technical guide—sulfuric acid enterprise environmental risk classification method（trial）”[2011]No.106,most of the raw materials,intermediate products,products and end“three wastes”of the sulfuric acid industry were risk substances,which were particularly prone to leakage accidents due to equipment failure,aging damage,bad weather,etc.,even fires.The protential environmental risk sources needed to be on guard.According to“Classification method for environmental accident risk of enterprise”（HJ941-2018）,took the sulfuric acid enterprise in Hubei an example to conduct environmental risk analysis,identified the environmental risks,predicted the risks,determined the risk level and proposed the relevant prevention measures to reduce the risk to achieve an acceptable level.The study could provide technical basis for the revision of“Emission standard of pollutants for sulfuric acid industry”（GB 26132-2010）,making it scientific and operable.At the same time,it could promote industrial technological progress,achieve pollutant emission reduction and improve environmental quality.In addition,the study could provide theoretical and practical reference for environmental risk identification,prediction and preparation of emergency plans for sulfuric acid production enterprises.