Reading guidance：Hot mud in addition to containing fine particles of iron oxide skin, often contain a large number of oil, when the plate and frame filter press, belt type filter press or vacuum filter and filter dehyd

     Hot mud in addition to containing fine particles of iron oxide skin, often contain a large number of oil, when the plate and frame filter press, belt type filter press or vacuum filter and filter dehydration equipment with, general cloth to be blocked and cloth wash difficult. Generally require pre treatment measures taken here primarily to by rare earth disk set of water treatment device to complete mud dehydration, can save concentrated pool, reduce investment. Problems existing in the process of sludge dehydration operation analysis and improvement measures.
   1. High moisture content problem of sludge discharged in magnetic press
     Magnetic squeeze dehydration machine is mainly composed of the transmission system (motor, reducer, chain wheel, gear), dehydration system (magnetic roller, elastic roller, slag discharge plate), in and out of the slag system (slag trough, slag tank) and the frame of four parts.Works: moisture content 90% the left and right sides of ferromagnetic sludge from slag into the mouth into the machine, into the semicircle groove casing slag, the ferromagnetic material and the floccules was magnetic tube adsorption, absorption and with magnetic suction tube running out of the liquid surface, the part of the water and the separation of slag by oneself, decrease the moisture content of slag, slag by scraping the slag to the secondary crushing, is elastic roller and extrusion, the pressure of slag water drop to below 40%, after dehydration of slag, along with the magnetic suction tube down the rotation and slag discharge, discharge of falling out of the syringes press filtrate by the slag bath to filtrate the drainage hole at the bottom of the discharge of pool. Equipment has overflow pipe, such as overload situation, redundant ferromagnetic sludge can be overflowed through the overflow tube.
  A. Analysis
    wet slag from rare earth magnetic disk will be dried by magnetic press machine. Sludge is with high moisture content, which will lead to difficulties to the transportation. There are many malfunctions for press machine and running maintenance cost is high. It is inferred that problems mentioned above are caused by adaptability. Magnetic press dehydration is relevant to the types of steel. After times’ tests, Rolling production line for each different kinds of steel, the magnetic press mud water content were detected, no greater volatility. Moreover, this study investigated the other steel rare earth disk purification water treatment technology and its application, also have no this law, and thus eliminate the reason. Later, found in the replacement of magnetic press roller, change every time a new roller, found a mud is dry. Outward conditions can be achieved, but the use of time is short, generally use a week after press mud will thin. Therefore, we on the magnetic press structure principle, pressure and material characteristics to analyze and study.
Materials used for magnetic press machine are usually special compounds which are shaped by cylindrical sponge and with high resilience. These materials also have good absorption ability.But this kind of material in the actual operation, if rare earth disk out of the wet slag flocculation effect is not good, fine particles into the magnetic press will soon invade into elastic pressure and pore, leading to decreased and the adsorption properties of pressure, decrease in processing efficiency, crush the same reduced, a large amount of sludge with the filtrate flow away, press out the moisture content of slag will also increase.
B. Solutions and disposal effects
   Hot rolling turbid circulating water before entering the rare earth disk, successively adding the polymerization aluminum chloride, polyacrylamide, the water of the magnetic suspended impurities and non magnetic particulate matter and residue forming the flocculation, for rare earth disk removal of impurities in the water, but the flocculation of the group, with the flow not faulting movement and in rare earth disk machine adsorption plane scraping, have broken the phenomenon.
     In order to solve the above problems, we decided to rare earth disk outflows of wet slag before entering the magnetic squeezing dewatering machine, namely in the rare earth disk spiral slag scraping mouth again a flocculant dosing, the impurity particles flocculation again, the formation of large particles magnetic floc, and improve the magnetic squeezing dehydration efficiency of the machine. After the transformation, magnetic squeezing extruder slag in the moisture content decreased to below 40%, and the equipment operation stability, elastic pressure and the replacement cycle was prolonged to the expected effect.
2. Mud accumulated disposal in horizontal flow oil separator tank
 A. Problem analysis
    In existing disposal process, the problem of the accumulation of the flat flow oil separator is also more serious. The main role of the structures is removal turbid water surface oil slick, in addition to the regulating pond, but not the design of the mud system, long-term operation, the bottom of the pool sludge will continue to increase, the thickness of the layer of mud increased, which will lead to isolation oil pool overflow water carrying suspended solids, it is difficult to ensure the water quality of the system stability.
    Horizontal oil separation pond sediments, mainly from rare earth disk processing the turbid water, flows through the flat flow oil separating pool water residual impurities in suspension natural subsidence, the sludge is mainly with the magnetic colloid flocculation, lighter weight and slow sedimentation velocity, but when through horizontal separation of oil tank, hydraulic retention time and colloid flocculation will increases while the natural settling to the bottom of the pool, and the sludge does not contain magnetic, not through the magnetic force in the prior art press dehydration treatment. Therefore, horizontal oil separation tank sludge treatment need to introduce a set of sludge dehydration equipment.
  B. Solution----application of LW type screw discharge centrifugal subsider
   LW type screw discharge centrifugal subsider is mainly composed of main motor, auxiliary motor (turbo brake and spacing protection device ), differential mechanism, spiral body, drum, main shaft, engine base and etc. Working principle: suspension enters drum from discharge port through Spiral body. with the action of fast rotation, heavy particles will stick on inner wall of drum. Screw blades which do relative motion compared with drum will eliminate solid particles sticking on drum wall and discharge out. After the separation of the supernatant by liquid plate opening overflow drum. Between the body and the spiral drum relative motion (i.e., difference speed) is realized through the differential and its size by an auxiliary motor to control, in order to achieve the centrifuge of the material continuous separation process.
    Due to advection pond sediments belong to the accumulation of long-term operation, periodic processing, processing quantity is small, according to the characteristics of the sediment, combined with practical and operating cost, need to choose a covers an area of small, high degree of automation, good dehydration effect, equipment maintenance convenient sludge dehydration equipment. After the study, LW type spiral unloading centrifuge (horizontal decanter centrifuge dehydration equipment become the best choice. Treatment systems supporting a homemade sludge regulation pool, dosing equipment. Equipment installation, commissioning and operation, to achieve the desired effect, horizontal oil separation pond sediment has been cleared up.
 
   
 
 
 

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