In the battle of sewage treatment without gunpowder, there are many magical tricks to make denitrification efficiency skyrocket. Let's take a look!
There are considerations for carbon source 'feeding'
Denitrifying bacteria are like a group of picky and cute little diners, they need to find the right "food" - a carbon source. Methanol, ethanol, sodium acetate, and other easily biodegradable carbon sources are their favorite and can be quickly "digested". Methanol is one of the stars, widely rebranded, and once added, its denitrification rate surges up like chicken blood.
However, the amount of this' feeding 'needs to be carefully controlled. Too little investment, denitrifying bacteria hungry, lack of enthusiasm for work; Overinvestment is like overeating, with COD in the effluent directly exceeding the standard and sludge production also increasing rapidly. Generally speaking, maintaining a carbon to nitrogen ratio of 4-6 is like arranging a nutritionally balanced package for denitrifying bacteria, resulting in high work efficiency.
Reaction condition "Big Health Care"
1. Dissolved oxygen "retreat retreat retreat retreat": Denitrifying bacteria like to work in the dark, so dissolved oxygen needs to be controlled below 0.5mg/L, allowing them to fully exert their power in the oxygen deficient small world and quickly remove nitrogen from sewage. If the dissolved oxygen is too high, it's like disturbing someone's rest in broad daylight, and denitrifying bacteria will go on strike.
2. pH value is "stable as Mount Tai": denitrifying bacteria are also very picky about pH value, and 6.5-8.0 is the "small nest" they feel comfortable in. If the pH value is off, quickly use "little helpers" such as sodium carbonate and hydrochloric acid to adjust and keep the denitrification enzyme active, otherwise the enzyme will strike and the denitrification efficiency will cool down.
3. The temperature is just right: Denitrifying bacteria are small creatures that are sensitive to both cold and heat, and their optimal growth temperature is between 20-30 ℃. In winter, when the temperature drops, quickly wrap the reactor in a "little blanket" or ask a heating device to help raise the temperature. Don't let it freeze, otherwise it will work slowly.
Microbial community 'major transformation'
1. Selection of high-efficiency bacteria "special forces": In the sewage treatment system, there are some "special forces" strains with super denitrification ability hidden. Find them, cultivate and enrich them in a delicious and tasty way, and then inject them into the reactor with a brainstorm, like injecting elite power into the army. It's difficult not to improve denitrification efficiency.
2. "Golden control" of sludge age: Sludge age is like a "growth diary" of microorganisms, affecting their composition and activity. Generally speaking, giving denitrifying bacteria a longer sludge age is like giving them enough time to grow and learn, which is more conducive to their growth and reproduction. Usually, by controlling the sludge age to 10-30 days, denitrifying bacteria can work efficiently and happily.
Reactor Transformation Chronicles
1. Choose the right reactor "equipment": A good reactor is like a powerful equipment for a superhero, such as the anaerobic aerobic (A/O) process, which divides the anaerobic and aerobic sections reasonably, creating a dedicated workspace for denitrifying bacteria; The biofilm reactor is also very powerful, allowing microorganisms to adhere tightly to it like ants, greatly improving denitrification efficiency and achieving first-class sewage purification effect.
2. Hydraulic condition "major upgrade": The water flow in the reactor should not be chaotic like headless flies, but should be evenly distributed to avoid short flows and dead corners. This requires a reasonable design of the inlet and outlet methods, coupled with the "little assistant" of the mixing equipment, to fully "embrace" the sewage and microorganisms, so that the efficiency of denitrification reaction can naturally increase.
