How should high-temperature hydrogen chloride-containing exhaust gas mixed with silica dust be treated?
Thread Content
This post was last edited by sunjl1981 on 2013-1-6 at 20:22. The waste gases emitted from the furnace contain hydrogen chloride and silica dust as their main pollutants. The exhaust gas temperature is around 250 degrees Celsius. The existing process involves first spraying water to reduce the gas temperature to around 150 degrees, after which it enters a packed tower where it is absorbed by water. All pipes are fiberglass reinforced plastic pipes, and the fans are also fiberglass reinforced plastic fans. Problem: The spray water used for cooling becomes acidic after circulation, and this acidic water is carried by the gases into subsequent pipes and fans. It causes severe corrosion and leakage near the fan. The fan lost its balance after just over a year of use; it experienced severe vibration, and there was also a lot of acidic waste gas leaking near the fan. After being circulated multiple times in the packed tower, the water used for absorption has an acid concentration of around 10%, and it is no longer possible to increase this concentration further; it has no value for recovery, and dealing with such acidic wastewater is also quite troublesome. If the processing procedures and equipment are redesigned, what would be the most appropriate approach? Please give me some guidance. # , , &
It’s so simple to put it. How is absorption and neutralization achieved? Use a packed tower? Or graphite falling film absorption? Could we make the discussion more specific?
A storage tank will do; add alkali and then measure the pH value – a slightly alkaline level is sufficient
Two points to note: 1. The temperature of the gas entering the packing tower is still too high; this will affect the lifespan of the packing tower as well as that of the pipelines and equipment used earlier. It might be advisable to increase the flow rate of the water spray and to maintain an appropriate temperature for the spray water. 2. Add alkali to the circulation tank of the packed tower to maintain a weakly alkaline condition in the circulating water, and control the concentration of brine (by continuously or intermittently discharging some of the brine for desalination). Another factor is the quality of the fiberglass lining; if it is poor, the slightly alkaline saltwater can cause the fiberglass to gradually corrode over time.