Characteristics of activated sludge during the synthetic wastewater treatment

Svojstva aktivnog mulja te karakteristike obrade sintetske otpadne vode sastavljenoj od glukoze, peptona i amonijevog klorida tijekom 60 dana u membranskom bioreaktoru s uronjenim membranama opisani su u ovom radu. Proces obrade vode vođen je uz naizmjeničnu aeraciju i konstantan protok otpadne vode. Uklanjanje organske tvari bilo je vrlo učinkovito (98%), a postignuto je i visoka učinkovitost uklanjanja dušika s 80 mg/L na vrijednosti manje od zakonski propisanih. Pri kontinuiranom radu membranske filtracije uočeno je značajno začepljivanje membrane u fazi rada bez aeracije, ali je upotrebom strujanja suspenzije aktivnog mulja preko membrane začepljivanje značajno smanjeno, pa se proces obrade mogao nesmetano odvijati kroz duže vrijeme. Srednja brzina denitrifikacije bila je oko 1 mg NO3-N/gMLSS h. Specifična brzina nitrifikacije je s početnih 2,07 mg NO3-N/gMLSS h, uz smanjenje na 0,08 mg NO3-N/gMLSS h 38-tog dana pokusa, dostigla 1,88 mg NO3-N/gMLSS h zadnjih dana pokusa nakon dodatka mikroelemenata i fosfora u sintetsku otpadnu vodu.The properties and characteristics of activated sludge during treatment of synthetic wastewater based on glucose, peptone and ammonium chloride in membrane bioreactor with submerged membrane are described in this paper. Waste water treatment was conducted with intermittent aeration and a constant flow of wastewater. Removal of organic matter was highly effective (98%), and high efficiency of nitrogen removal from 80 mg/L to less than discharge limit was also achieved. During continuous membrane filtration a significant membrane clogging within period without aeration, but by using recirculation of active sludge on the membrane, clogging was significantly reduced, and the process could be carried out successfully. The average denitrification rate was about 1 mg NO3-N/gMLSS h. Specific nitrification rate on the beggining was 2.07 mg NO3-N/gMLSS h, then it decreased to 0.08 mg NO3-N/gMLSS and again in the last days on the 38th day of experiment it reached 1.88 mg h NO3-N/gMLSS,after addition of trace elements and phosphorus in the synthetic wastewater