Garbage leachate refers to a high concentration organic wastewater formed by the moisture contained in the garbage itself, rain, snow, and other moisture entering the landfill site, deducting the saturated water holding capacity of the garbage and covering soil layer, and passing through the garbage layer and covering soil layer.
DTRO equipment processing manufacturer
1、 Reverse osmosis membrane treatment technology
Reverse osmosis membrane treatment technology is a complex membrane separation technology that can block all dissolved salts and organic matter with a molecular weight of over 100, but water molecules can pass through. The desalination rate of cellulose acetate membrane is generally above 95%, and the desalination rate of composite membrane is generally above 98%. The selective permeation of reverse osmosis membranes is related to the dissolution, adsorption, and diffusion of components. Therefore, in addition to the pore size of the membrane, it is also closely related to the physical and chemical properties of the membrane, that is, closely related to the interaction between the membrane and its components. From the perspective of membrane shell structure, reverse osmosis membranes can be divided into two categories: roll up membranes (RO) and disc tube reverse osmosis membranes (DTRO). The water quality requirements for the membrane inlet are relatively high, usually requiring UF or NF as pretreatment processes to reduce SDI to less than 5 and suspended solids to less than 5mg/l, in order to prevent membrane fouling; The DTRO membrane process is based on the disc tube reverse osmosis membrane. The core technology of this process is the unique structure of disc tube reverse osmosis membrane, which makes it possible to directly treat landfill leachate using reverse osmosis membrane.
DTRO membrane technology is a type of disc tube membrane technology, which can be divided into two categories: DTRO (disc tube reverse osmosis) and DTNF (disc tube nanofiltration). It is a patented membrane separation equipment. This technology is specifically developed for the treatment of leachate. Its membrane component structure is completely different from traditional roll film. Raw liquid channel: The disc membrane module has a patented flow channel design, which opens up the flow and allows liquid to enter the pressure vessel through the population. It is assembled from the other end of the channel between the baffle and the shell, and the other end is flanged. The feed liquid enters the deflector through 8 channels, and the shortest distance between the treatment liquid flow and the treatment liquid flow quickly passes through the filtration membrane. Then, it reverses 180 ° to the other membrane surfaces, and flows from the narrow groove at the proportional center to the next guide plate, forming a circle from the circumference of the guide plate to the center of the circle on the membrane surface., Then, in the circumferential direction and towards the double "S" - shaped route at the center, the concentrate finally flows out from the feed end flange. The distance between the two polarizers of the DT assembly is 4mm, and there are certain convex points arranged on the surface of the polarizers. This special hydraulic design allows the treatment fluid to form turbulence during collision under the pressure on the surface of the filter membrane, improving the transmission rate and self-cleaning function, effectively avoiding membrane blockage and concentration polarization, and successfully extending the service life of the membrane; It is easy to clean the scale on the diaphragm during cleaning, ensuring that the coil membrane group is suitable for treating high turbidity and high sand content wastewater, and adapting to more adverse inlet conditions.
2、 Taking a certain power plant project as an example. The filtrate output of this project is 600m3/d, and the design adopts a "biochemical treatment+UF+DTRO" treatment scheme.
Introduction to DTRO Equipment System Process
The effluent of the ultrafiltration system is filtered by the filter element and enters the DTRO membrane tower. A high-pressure pump and shock absorber are installed in front of the DTRO membrane column. The high-pressure pump provides sufficient pressure for the DTRO membrane, and the shock absorber can activate the rear DTRO. Membrane columns can achieve relatively stable pressure. In addition, to ensure the surface flow rate of the DTRO membrane, a portion of the DTRO membrane concentrate is returned to the inlet of the membrane column, and then enters the DTRO membrane column through the action of an online booster pump. The DTRO membrane column concentrator is equipped with a pressure regulating valve to control the pressure inside the membrane group and achieve the necessary water purification rate. The concentrate generated by the system is pushed into the concentrate collection tank.
Install flow sensors and conductivity meters on the inlet and outlet pipelines of the system to monitor the flow and conductivity of incoming and produced water. Pressure sensors are installed at various stages of the circulation pump, high-pressure plunger pump, membrane circulation pipeline, clear liquid pipeline, and concentration pipeline to monitor the pressure at each stage. Equipped with pH sensors and temperature sensors, real-time monitoring of changes and concentration of the supernatant. Each tank or tank body is equipped with a liquid level switch to monitor the liquid level; Install a level gauge inside important containers to monitor the liquid level.
Estimation of pollutant removal rate in DTRO equipment system
According to the current operating data of a certain power plant's leachate treatment system, the inlet water quality parameters of the system are: CODCr 40000~70000mg/L, BODs 20000~35000mg/L, ammonia nitrogen 1000~1500mg/L, SS 10000~1500mg/L, pH 5~7; The inlet water quality parameters of the DTRO membrane system are: CODcr ≤ lOOmg/L, BODs ≤ 200mg/L, ammonia nitrogen ≤ 50mg/L, SS ≤ lOOmg/L, pH 6-9; System effluent water quality parameters: CODcr ≤ 100mg/L, BOD5 ≤ 20mg/L, ammonia nitrogen ≤ 15mg/L, SS ≤ 70mg/L, pH 6-9. From the above data, it can be seen that the removal rate of CODcr by DTRO membrane can reach 98%, the removal rate of ammonia nitrogen is about 50%, the removal rate of suspended solids is 75-80%, and the removal rate of salt can reach 96%. Among them, the removal rates of COD and salt are particularly significant.
