Monthly Archives: May 2020

Safety Management of Centrifuges

For the cause of centrifuge accident, in order to ensure the safety of centrifuge use, we should strengthen the following aspects of management.

Correct installation of centrifuges

(1) Power supply voltage. The voltage fluctuation should meet the industry standard within 10%, otherwise the centrifuge can not run normally. If the voltage fluctuation exceeds the industry standard, the voltage regulator should be used to meet the normal working needs of the instrument.

(2) Protection of grounding. The indoor should have independent ground wire, the ground wire should be reliably connected with the centrifuge shell, the ground resistance <4Ω, the ground wire can not be connected to the heating pipe, the water pipe, so as to avoid the occurrence of electric shock accident.

(3) Centrifuge placement. A suitable location should be selected according to the performance of the centrifuge, and the general low speed centrifuge (table) can be placed on a smooth, solid table (its base is equipped with rubber suction feet, with the help of atmospheric pressure and the weight of the instrument itself, close to the table); large capacity low speed centrifuge and high speed centrifuge should be placed on the corresponding solid ground, horizontal placement. Centrifuge weighing hundreds of kilograms, should be placed on a very solid ground, and equipped with dustproof, moisture-proof equipment. There is no strong vibration source near the centrifuge, avoid heat source and direct sunlight around, leave some space around, keep good ventilation.

(4) Host installation. Adjust the screw to support the machine foot to the ground, observe and adjust the screw through the level to make the main engine stable. Install the rotor, position the fastening, place the leveler in multiple parts of the rotor, adjust the screw until the leveler bubbles are all located in the center. Ensure that the 4 feet are balanced and the suspension is not allowed.

Common Malfunctions of Centrifuge and Methods of Centrifuge Maintenance and Treatment(1)

In the process of using the centrifuge, it is necessary to strictly follow the operating manual of the centrifuge model. This is certainly to be followed, but the machine, like people, occasionally appears “sick “, that is, machine failure. In the face of failure is their own roll up sleeves to start repair? Or call the repairman? Today, according to the practice experience of centrifuge maintenance, we have sorted out some common problems and methods of centrifuge maintenance.

  1. Oil pressure fault problem. This kind of fault mainly shows that there is no oil pressure, too low oil pressure or too high oil pressure. Its treatment is:

(1) No oil pressure. Check whether the oil filter is blocked, whether the pressure gauge is damaged, whether the tubing and joints are connected and loose, broken, and whether the tubing is unblocked.

(2) Oil pressure is too low. The normal outlet oil pressure of the centrifuge in this coal preparation plant is 3.0~3.5 bar, If the oil pressure is too low, check whether the suction pipe from the oil pump passing through the filter to the oil tank is unblocked; check whether the oil line is leaking; check whether the coupling between the motor and the oil pump shaft is damaged, otherwise replace the coupling; whether the oil pump is damaged, otherwise replace the oil pump.

(3) Excessive oil pressure. When the oil pressure of the centrifuge is too high, check whether to add appropriate mechanical oil to the tank according to the requirements of the equipment usage instructions; check whether each pipeline is blocked, if there is a blockage problem, use compressed air to clean the sundries in the pipeline.

B. Excessive vibration fault. The problems of excessive vibration during the operation of the centrifuge are mostly caused by incorrect installation, blocking deformation of the sieve basket, blocking of the coal channel between the sieve basket and the scraper, and loosening of the bolts. The solutions are as follows: check whether the sieve basket is blocked, worn out or deformed; check whether the spring of the vibrator is aged; check whether there is a fine coal accumulation on one side of the sieve basket; check whether the wedge sieve basket is damaged, deformed or unbalanced; check whether the anchor bolt is corroded and firm; check whether the bearing is damaged and replace the bearing if it is damaged; if the new vibrating motor is replaced, check whether it is consistent with the load of the replaced motor.  And to match the other side of the motor, the two motors should be assembled the same.

Wastewater Treatment

With the accelerated development of society, the sewage wastewater discharged through food, chemical and other industries can be seen everywhere, the national government has also issued corresponding targets for sewage treatment, and for the way of sewage treatment, it needs physical, biological and chemical treatment to remove impurities. Now, the common solution to this problem is to separate sewage and waste residue through decanter centrifuge, in the process of biological and chemical auxiliary treatment, and then through the continuous circulation of centrifuge equipment after the sewage can be turned into available water resources.

The use of decanter centrifuges to treat sewage problems mainly goes through the following stages:

Stage 1: Screening and preprocessing

Because many waste water because of external reasons, there will be too many solid waste inside, such as some common garbage items, cosmetics, sanitary products, rags, plastic products, stone particles and so on. And in order to avoid damage to separation equipment, we have to filter out the waste in the wastewater, do this step is very important.

Phase II: Physical/Chemical treatment

This stage can remove a lot of solid impurities, it is necessary to use decanter centrifuge equipment, but in this process to the treatment of waste water to add a certain amount of coagulant or polymer and other chemical agents, to the sewage of small particle impurities to polymer, so as to facilitate decanter centrifuge equipment for solid-liquid separation treatment, if the sewage contains oil, oil and water separation can be carried out after re-separation treatment.

Phase III: Biological treatment

This stage is the final stage, starting with the adjustment of sewage through physical filters, such as sand filters, to remove residual organic and inorganic pollutant particles in the water. The second is sterilization, which can be used to sterilize water quality by ultraviolet light or chlorination.

It can be seen from the above steps that the cost of treating wastewater into available water resources is high, and it is very tedious at the same time. Liaoning Fuyi production of decanter centrifuge can do continuous operation processing, and can be different material separation requirements to develop appropriate centrifuge equipment, if there are other details need to know, can be at any time at any time.

Drilling Mud Curing Treatment

In recent years, with the increasing environmental pollution, the state pays more and more attention to environmental protection. Especially this year, the special action of environmental protection swept across the country, in order to let enterprises attach importance to environmental protection, so that enterprises in the process of production to achieve the purpose of energy conservation and environmental protection. For the construction engineering industry, the drilling cast-in-place pile mud treatment is an urgent need to solve the environmental protection point, mud discharge absorption point on the surrounding environment is also huge, so not to solve this problem, the construction industry will also face the risk of closure and regulation.

In the past, the mud discharged by bored piles was transported to the designated absorption site through mud tankers. The mud sedimentation tank is set up in the absorption yard. After three stages of sedimentation, the digger digs out the sediment and transports it to the evaporation tank. After natural dehydration and solidification, it is transported to the site as subgrade filler, earth backfill or local backfill waste soil.

Mud curing treatment

In the process of precipitation and evaporation, occupying a large area of the site will cause certain damage to the surrounding ecology. The sewage discharge after sedimentation and the landfill of waste soil caused some damage to the surrounding environment. If the harmful substances in the mud are buried on the spot, it is easy to cause pollution and damage to the surrounding groundwater sources.

Because of the damage of mud and environmental protection special activities, our project has introduced the mud curing dehydration treatment equipment. The mud curing equipment we introduced is “potion” curing, the moisture content of the mud block after dewatering is controlled at about 20%, which can reach the condition of earth-moving out; the water used for the construction of bored cast-in-place piles can be recycled through dehydration equipment, and the water use rate is up to 95%; the mud curing field is digested to reduce the pollution of the surrounding environment.

Slurry curing process

The main parts of the treatment process of mud curing treatment equipment are: liquid mixer, mud curing reaction tank, mud curing filter press, mud pressure filtration water collection system. First, the liquid is mixed into the liquid mixer to stir, and then the curing agent is prepared, and then a branch pipe is set up on the input pipe of the mud curing reaction tank, and the curing liquid mixer is connected, and the proportion of the mud mixing liquid is controlled by the liquid flow rate and the mud flow rate. After mixing the appropriate proportion of liquid slurry into the curing reaction tank, it is pressurized and transported to the mud curing filter press, and the water in the mud is removed by physical and mechanical extrusion.