Ammonia nitrogen levels in the aerobic tank for landfill leachate remain high
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I’ve recently been working on the treatment of landfill leachate, using a process that involves UASB, anoxic phase, aerobic phase, ultrafiltration, and nanofiltration; currently, 130 cubic meters of water are fed into this system per day. The raw water has a COD level of 45,000 and an ammonia nitrogen level of around 2,500. In the UASB tank, the COD in the effluent is 3,600 while the ammonia nitrogen level is 1,600. In the aerobic tank, the COD in the effluent is around 1,000 and the ammonia nitrogen level is over 800; the dissolved oxygen level increases very rapidly. No water has been added in these past two days, and glucose has been continuously added. However, the ammonia nitrogen level in the aerobic tank isn’t decreasing – it’s actually increasing – and the pH value has reached 8. I hope experts can help analyze the reasons for this
Landfill leachate contains a high level of organic nitrogen; as organic matter decomposes, this organic nitrogen is converted into ammonium nitrogen. Ammonia combines with water molecules to form ammonia water, which has a weakly alkaline nature, resulting in an increase in pH. Additionally, the aerobic removal of COD also generates a certain amount of alkalinity. In my opinion, it is not advisable to send wastewater with such high ammonia levels directly into the biochemical treatment process. I suggest reducing the ammonia level to below 200, and ideally below 100, before proceeding with biochemical treatment. There are already mature processes available for this purpose, though they require more energy.
What is the aeration volume you are using, and which type of blowout jet aerator do you have? What is the sludge concentration? We have participated in over 20 leachate treatment projects, and all of them are operating properly
Could you talk about the data related to the project you are in charge of, such as operating parameters, water quality before and after treatment, and the level of pollutant removal?
Could you talk about the data related to the project you are in charge of, such as operating parameters, water quality before and after treatment, and the level of pollutant removal?
Calculate sludge concentration, nitrogen load, air volume, etc
Your anaerobic removal rate is very high, reaching 90%; the aerobic treatment yields only a 70% removal rate, while an aerobic process should achieve at least an 85% removal rate. The effluent concentration is around 500 as well. It’s necessary to test the MLSS level and calculate the organic load. With the ammonia nitrogen level reaching 800 before the aerobic treatment, what does that mean? The wastewater has a very strong odor. A slightly higher pH value in the aerobic stage isn’t a problem, as long as it doesn’t exceed 9; this helps convert ammonia nitrogen into gaseous ammonia, which can be removed through aeration. It’s also important to control the internal recirculation and use denitrification to remove nitrogen