Dairy processing waste water treatment plant in
.1 Design principles
2.1.1 According to effluent characteristic, to chose suitable technical process, to make technique reliable, operation convenient、easy maintenance inspection、simple process;
2.1.2 In the premise of guarantee treatment effect, possible to reduce occupy area、construction investment and daily operation cost.
2.1.3 The waste water treatment equipment should chose reliable performance、steady operation、high automatic degree save energy superior product, to guarantee
Project quality and investment efficiency;
2.1.4 Fully considering second pollutant prevention, equipment resistance corrosion, noise reach standard, to lest influence surrounding environment.
2.2 Sewage treatment process chose
milk waste water main contain large solubility pollutant, contain Sugar, starch, protein, fatty acids, with better biodegradability, and it didn’t contain poison and harmful matter, and didn’t contain large particles suspended matter, the sewage is milk white, belong to high concentration sewage.
In view of such sewage condition, combine our company actual practice,to confirm the following treatment process:
Detailed process flow:
The collecting waste water will first enter into mechanical bar screen to intercept bigger suspended solids, then flow into equalize tank; due to waste water flow rate in each day, so we set equalize tank to balance water volume and quality, to make water uniform enter into following package sewage treatment plant; there are set 2pcs sewage lifting pump in equalize tank bottom, which was control by floating ball liquid level switch, when waste water liquid level in equalize tank was lower, the sewage lifting pump will automatic stop working, whole sewage treatment plant will stop work too;
The waste water will pump to dissolved air floatation tank from equalize tank, during this process,dose PAC、PAM etc flocculants into waste water, at the same time, adjust PH by dosing acid or alkali, which can remove small floating solids and oil grease in water, it can reduce 30% BOD and COD,the floating scum will flow into sludge tank by gravity, the cleaning water flow into hydrolysis acidify tank , it can make hard biodegradable organic matter decomposed into small molecule organic matter,to improve waste water biodegradability,then waste water enter into oxidation tank, to further reduce organic matter in water, after that, flow into MBR tank, there are set MBR hollow fiber membrane, the microorganism in MBR reactor can make the pollutant assimilation and dissimilation,
The dissimilation product is non harmful CO2 and H2O, assimilation product is microorganism composition matter; the membrane module mainly use to solid liquid separation, microorganism solids can effective hold back in reactor, to guarantee the effluent water quality steady; the MBR effluent water will suction into cleaning water tank, the cleaning water can be reuse in irrigation or washing tiolet after make disinfection;
most of sludge in MBR tank will backflow to hydrolysis acidify tank,to supply nitrate and nitrite for anoxic section, to reach denitrification purpose,
the surplus sludge will flow into sludge tank, use frame filter press to make sludge dewatering treatment, the mud cake will transport away;