Regarding the issue of nutrient addition
Thread Content
Dear teachers, when are nutrients added? They are used during sludge cultivation, but is it necessary to add them during the operation of the process? Also, how can we determine which nutrient is lacking in the water? What are the symptoms of a deficiency in each nutrient? Which indicators need to be measured in order to determine which nutrient is lacking in the sludge? How exactly is it calculated to find out how much is missing? The questions are a bit messy; please
This post was last edited by ifay2011 on 2015-9-16 at 16:52. 1. The nutrients you mentioned should refer to carbon sources, nitrogen sources, and phosphorus sources. It needs to be added when acclimating the sludge; during normal operation, no addition is required if these substances are present in sufficient amounts in the wastewater. However, whether the supplementation is achieved by adding certain chemicals or by introducing other water sources rich in such nutrients can be determined based on the specific conditions on site. 2. Determine what is lacking by testing various indicators in the wastewater. Generally, carbon sources are reflected by BOD5; if BOD5 cannot be measured, CODCr can also be used (though it is not as accurate as BOD5) ； The nitrogen source can be determined by measuring total nitrogen, ammonia nitrogen, etc ； The phosphorus source can be used to measure total phosphorus. 3. Generally, a ratio of 100:5:1 for carbon sources, nitrogen sources, and phosphorus sources in aerobic processes is reasonable, but this is not absolute. It depends on what goal you want to achieve; the phosphorus proportion cannot be too high, and it’s necessary to adjust this ratio by adding carbon and nitrogen sources. 4. I’m not sure what symptoms occur when a certain component is missing – does it refer to the operation process?
The nutrient ratio in wastewater is generally C:N:P=100:5:1 for aerobic conditions; it is sufficient to be within this range. If it is not within this range, nutrients need to be added according to the proper ratios, and they must be included when using symbiotic bacteria.
For anaerobic conditions, a nutrient ratio of 200–250:5:1 is sufficient. When there is a shortage of carbon sources, methanol, glucose, flour, etc., are often used as supplements. Nitrogen sources include urea, compound fertilizers, ammonium salts, etc., while phosphorus sources comprise potassium dihydrogen phosphate, phosphoric acid, sodium phosphate, etc.