Analysis and Research on Waste Gas Treatment in Ceramic Industry

Time: 2018-12-30 10:53:30

In recent years, with the increasing market demand, the ceramic industry has developed rapidly. According to statistics, the total output of China's building ceramics has reached 60% of the world's total output. While it has made tremendous contributions to the economy, it has also brought enormous pressure on environmental protection and energy consumption. In 2010, the state promulgated the "Ceramic Industry Pollutant Emission Standards" (GB25464-2010). In 2014, it also issued its amendments (No. 84 of the Ministry of Environmental Protection announced in 2014), which made a decision on pollutant treatment in the ceramic industry. Strict requirements make pollutant management a major challenge for the ceramic industry.

The pollutants in the ceramic industry are mainly divided into waste water, waste residue and industrial waste gas. Among them, industrial waste gas has attracted much attention due to its large emissions and affecting the atmospheric environment that is closely related to people's lives. Industrial waste gas in the ceramic industry mainly contains dust, sulfur dioxide, nitrogen oxides and other pollutants, which are harmful to the atmospheric environment. Different treatment methods for different pollutants, through the analysis and comparison of the treatment of air pollutants treatment technology in the ceramic industry that has been put into use, and draw corresponding conclusions and suggestions for improvement, industrial waste gas for the future ceramic industry Processing has great practical significance.

2 Ceramic industry waste gas treatment monitoring and evaluation

According to the principle of selecting enterprises with complete governance facilities and sampling facilities before and after the treatment facilities, and considering the production status of enterprises, this paper selects 25 enterprises from 62 ceramic enterprises in Foshan for monitoring and monitoring the number of chimneys up to 120. Article, mainly analyzes the emissions of soot, sulfur dioxide, nitrogen oxides and ammonia.

According to the existing standard method of fixed pollution source exhaust gas, this paper selects the "Sampling method for particulate matter in fixed pollution source exhaust gas and sampling method of gaseous pollutants" GB/T16157-1996 as the sampling and monitoring basis for each monitoring project, and selects the "fixed pollution source row by weight method". Determination of particulate matter in gas and sampling method of gaseous pollutants" GB/T13157-1996, "Determination of sulfur dioxide in stationary pollution source, determination of potential electrolysis" HJ/T57-2000, "Determination of nitrogen oxides of fixed pollution sources" HJ693-2014 and "Determination of Ambient Air and Exhaust Gas Ammonia Spectrophotometry" HJ533-2009 Analytical Method for Determination of Soot, Sulfur Dioxide, Nitrogen Oxide and Ammonia Concentration. At the same time, in accordance with the requirements of environmental monitoring standards and specifications, quality control of the sampling process is carried out by means of on-site blanks, on-site parallel and other quality means. The quality of the analysis process is controlled by means of indoor blanks, indoor parallelism, and sample spikes to ensure data. Accuracy and authenticity.

2.1 Smoke treatment in the ceramic industry

The source of soot in the exhaust gas of the ceramic industry is mainly the particulate matter produced during the production process and the soot produced by the combustion of water gas and coal water slurry. From the data before and after the treatment, it is known that enterprises with coal-water slurry and water gas as fuels have significantly higher smoke and dust content before treatment than enterprises with natural gas as fuel. After applying dust removal technology, each enterprise can have good dust removal efficiency. The concentration of post-smoke is significantly reduced.

2.2 NOx treatment in the ceramic industry

Denitration technology is the main hand of the treatment of nitrogen oxides in the exhaust gas of the ceramic industry. The nitrogen oxides are treated by spraying reducing agents such as ammonia and urea. Although this method is effective, it has requirements for the reaction temperature. When used in the ceramic industry, the denitration efficiency is often affected by the temperature of the exhaust gas which does not reach its reaction temperature.

3 Analysis of waste gas treatment in ceramic industry

Through the comparative analysis of the exhaust gas treatment of different ceramic enterprises, the following points can be seen.

(1) Before the treatment, the concentration of soot in the exhaust gas of each enterprise is large, and the emission standard can be achieved after treatment. It shows that some ceramic enterprises still have backwardness in technology, and the introduction and transformation of technology should be strengthened. Moreover, the domestic flue gas dedusting technology has been relatively mature and the treatment efficiency is high, which should be widely used in the ceramic industry.

(2) Treatment of sulfur dioxide in the ceramic industry mainly involves two aspects: first, the use of clean energy, such as natural gas, to reduce sulfur dioxide emissions from the source; second, the use of desulfurization technology, such as wet desulfurization, dry desulfurization, etc. It can be seen from the comparative analysis that the application of desulfurization technology can make the concentration of sulfur dioxide in the flue gas of the ceramic industry reach the discharge standard.

(3) Although some ceramic enterprises have reached the emission standard after the treatment of nitrogen oxides in the flue gas, the treatment efficiency is not high, and although the emission concentration is lower than the emission standard, it is still high, and the operation and management are improper, resulting in an increase in ammonia slip. Great question. These problems require the industry to pay attention to environmental protection, increase investment, strengthen the operation and maintenance of denitration facilities, and improve its process operations.

4 Conclusion

As a pillar industry in many regions, the ceramic industry has also brought enormous environmental pressure to the region. The treatment of waste gas is a key project related to the national economy and the people's livelihood. The government should give strong support to the ceramic industry while improving environmental protection requirements. For example, by increasing the supply of natural gas and reducing the price of natural gas, the cost of waste gas treatment is reduced, and the progress of coal to gas is promoted. The ceramic industry itself should strengthen the implementation of environmental protection measures, improve environmental management, improve operational management and introduce new technologies, make waste gas treatment more effective, and contribute to environmental protection.