Working Theroy Of Decanter Centrifuge

Horizontal spiral discharge sedimentation centrifuge (referred to as decanter centrifuge) is working theroy of decanter centrifuge 03an effective separation equipment which use centrifugal acceleration generated by high-speed rotation into the acceleration of gravity to shorten thousands of times of the settlement time of solid particles than in the gravity field.

The solid particles are discharged from the drum through the screw conveyor continuously and without interruption.

The material is conveyed to the screw discharge port through the feeding pipe and uniformly distributed in the drum through the spiral discharge port which is rotated at a high speed, and the main motor drives the drum to rotate at high speed through the belt to generate thousands of times of gravitational acceleration.

Rapidly settlement and accumulation of the solids particles in the inner wall of the drum, there is a relative movement of the screw conveyor to the drum, which will continuously push the sediment towards to outlet. The sediment is mostly dewatered under the combined action of the screw conveyor squeeze and drum dehydration.

After the separation, the liquid is discharged freely through the liquid outlet point.

working theroy of decanter centrifuge 01

working theroy of decanter centrifuge 02

Sludge Oil Recovery Process

Ⅰ. Description
Slurry Oil Recovery Unit consists of heating mixing tank, rotary pump, screw pump, tricanter centrifuge, oil tank, DISC separator, water tank etc. Sludge oil recovery process 01The manifold consists of suction, mixing, fresh water, heating piping etc. Besides, plat form, walk ways, handrail, ladders are built for convenience and safety.

Total volume of the unit: 21m3, Total electric power: 198kw, Gross weight: 33 Ton. Slurry Oil Recovery Unit is mainly used for oil recovery performance.

Main working flow of the unit: 1. Rotary pump feed the heating mixing tank from slurry pit, Chemical inject device pump the chemical into heating mixing tank. The tank equipped with agitator inside and water stream coil outside.

Oily slurry is well-mixed when heating by the water stream and stirring by the agitator. 2. Tricanter feed pump feeds the well-mixed slurry into the bowl of tricanter centrifuge from the heating mixing tank.

Tricanter centrifuge separate the solids, oil, water through the high speed rotation. The solids are transferred by the screw conveyor, water and oil are collected by the water tank and oil tank. 3.

Screw pump pumps the oil into the DISC separator from the oil tank for further purifying. The Unit capacity is around 5~10m3/h
Ⅱ. Technical Details
Total volume:21 m3 Active volume: 20 m3 Total Power: 198 kw Heating mixing tank: 2 sets Oil tank: 1 set Water tank: 1 set Tricanter centrifuge: 1 set Disc Separator: 1 set Overall dimension: 17570 x13200 mm Gross weight: 33 Ton
Ⅲ. Main Configuration
1. Heating equipment Heating mixing tank (2 sets) Model: VN7000 Power: 11 kw Volume: 7 m3
2. Separation equipment Tricanter centrifuge (1 set) Model: LWS-500×2000 Main power: 55kw Shaft power: 18.5kw Capacity: 5~10m3/h DISC separator (1 set) Model: FBDB-211S Power: 15kw Capacity≤ 5m3/h 3. Transfer equipment Screw conveyor ( 1 set) Model: LSY300-5M Power: 7.5kw Capacity: 8-10 m3/h 4. Pumps Heating mixing tank feed pump (2 sets)
Model: XHB65-10/14-0.2 Power: 7.5 kw Head: 20m Capacity:10~14m3/h Tricanter Centrifuge feed pump (1 set) Model: XHB65-10/14-0.2 Power: 7.5kw Head: 20m Capacity: 10~14m3/h DISC separator feed pump (1 set) Model: XG040B01ZF Power: 2.2kw Capacity: 5m3/h Oil pump (1 set) Model: XHB125-60-1 Power: 37kw Capacity: 60m3/h Water Pump (1 set) Model: SCP 80-40-200 Power: 11kw Capacity: 15m3/h Chemical pump (1 set) Model: KD40/0.6 Power: 0.18kw Capacity: 0~40L/h 5. Oil tank (1 set) Model: VN5000 Active Volume: 5 m3 Dimension: φ1600×3400 6. Water tank (1 set) Model: VN3000 Active volume:3 m3 Dimension: 2100×1200×1500 7. Chemical Tank (1 set) Model:VN250 Active volume: 250L Dimension: φ800×1700 8. House (2 sets) 6000×2440×2800mm for Tricanter section 6440×2440×2800mm for Separator section 9. Pipe line
Ⅳ. Flow Process Description
Slurry Oil Recovery Unit has three types of suction pipe line. Heating mixing tank suction pipe, tricanter centrifuge suction pipe, DISC centrifuge suction pipe. Butterfly valves are adapted to all the suction pipes. Switch on the butterfly valves to ensure the system suction process.

Sludge oil recovery process 02

How To Do Waste Crude Oil Recycling

The oil industry produces large quantities of solid and semi-solid wastes called oily sludge. Oily sludge usually contains water, sand, oil, grease, organic compounds and metals.How To Do Waste Crude Oil Recycling 01

Due to the diversity of crude oil quality, the differences arising from the different processes used in the oil-water separation process, the leakage in the industrial process, and the mixing with a variety of other existing oily sludge, the composition of the oily sludge has a variety of difference.

These oily sludge can be produced in several steps of oil production and refining, for example in oil-water separation and settling at the tank bottom..

The high stability of the oily sludge is due to the oil adsorbed on the solid particles, resulting in the formation of the protective layer. The stability is enhanced by the presence of polar fractions in the oil, especially resins and asphaltene, which also contribute to the high viscosity of these sludge.

In addition, the protective layer is conducive to the production of microorganisms, but also for the diversity of microbial communities to provide a breeding cover, thereby causing environmental corrosion, which is reflected in each use of storage tanks, the storage tank will be corroded.

Oily remnants accumulate in the petroleum industry and cause serious environmental problems. This type of sludge is considered hazardous waste in many countries because it contains high concentrations of toxic components and therefore requires proper management. Recycling of the waste crude oil in such oily sludge is an ideal treatment because it not only recovers valuable energy, but also minimizes the concentration and total amount of hazardous waste. We benefit from the recovered oil and at the same time reduce the cost for the residual further disposal treatment.

There are various ways to recycle the waste crude oil. The cost and production efficiency mainly become the points when user choose their own. However, the combination of chemical additives, heating, and physical separation has undoubtedly become a mainstream choice in current processing methods, because of its mature technology, the equipment used is simple and easy to operate. Through different temperature configurations, chemical additives, core equipment, and even fine-tuning of the entire process, make it can adapt to different area of various sludge oil recovery.

Step 1: Pretreatment

In the waste treatment process, whether it is reduction, recycling or harmless treatment, after the initial experimental analysis of waste, in order to meet the next stage of the entire process requirements, will be pre-treatment of materials. Such pretreatment methods can be dilution, sedimentation, sieving, heating, demulsification, gel breaking, viscosity reduction and so on. Of course, in the treatment of certain special oily sludge, such as some heavy crude oil sludge , aging sludge, adding a certain proportion of light crude oil for dilution, in order to make it easier for the next separation, will achieve surprising results . In the initial classification of the waste sludge, according to the size of oil particles inside the sludge and the proportion of the solids, mechanical vibrating screen or roller screen to be chosen. According to the oil content of the sludge, sludge viscosity, different crude oil condensate point , we will choose different chemical additives to broken gel, breaking, and set the different heating temperature. As the entire process using pipeline transport, the main purpose of the pretreatment is to ensure the viscosity of oil sludge and liquidity suitable for the pumping process.

Step 2: Separation

After pretreatment, centrifugal separation is the most important part of the process. Due to the different density of the different physical phase, the different components will go through a specific orbit attribute to the centrifugal force. In general, the oily sludge components are divided into oil, water, solid. Separation equipment selection in the process should be based on the actual proportion of material components, and reduce the cost point of view , such as two-phase decanter centrifuge, three-phase decanter centrifuge, Disc separator and oil-water separator.

Step 3: Filtration

Taking the recovered crude oil quality into consideration, a filter system may be put into the process after the separation part. Or it’s even better to send the recovered oil to refinery plant for further purification process.

ZK separation is an experienced solution and equipment provider on oilfield waste management. The company has been dealing with oily waste including cured oil, cooking oil, engine oil, lubrication oil for more than 16 years. The valuable practice on projects enhance the production performance for various working condition and different

types of oily waste.

How To Do Waste Crude Oil Recycling 02

Recovery process of waste lubricating oil

In a variety of waste oil recycling process, the commonly used technologies are:
Settlement: Utilize density difference to remove the water and impurities. This is one of the simplest method, the mechanical impurities and suspended water droplets Recovery process of waste lubricating oil 01diameter between 0.05 ~ 10μm, the sedimentation rate is subject to Stokes law. The larger diameter of water droplets and impurities, the greater density difference from the oil, the easier to settle. With greater viscosity of the oil, the settlement is more difficult. Heavy oil with high viscosity and density can be heated as a solution in order to ease the settlement. Generally, oil temperature rise every 10 ℃, oil auto-oxidation rate doubled. However, the oil viscosity changes small while the temperature stays higher than 80 ℃. Thus, in the sedimentation process, the oil temperature is generally not more than 80 ℃.
Centrifugal separation: with the external driving force, that is, centrifugal force generated by high-speed rotation. Due to the density difference between the different phases, we can separate water, oil and solids.

Filtration: liquid go through the filter medium, suspended solids, solid particles and other impurities are retained. Filter media include: 1. Filter paper, dense textile; 2, blankets, asbestos, cotton yarn head; 3. Metal mesh. Filtration rates are inversely proportional to the viscosity of the used oil. In order to obtain the necessary filtration rates, heat treatment is usually required. Depending on the quality of the oil, the heating temperature will vary, but generally not more than 140 ° C.
Water washing: in order to get rid of water-soluble acid generated by oxidation reaction or flocculation to remove some of the suspended carbon ions from the waste oil. In some cases, we need to wash the waste oil. A good choice is to use distilled water in order to prevent saponification or emulsification. water temperature usually control at 60 ℃.
Adsorption: It’s a kind of refining on waste oil by using adsorbent in order to remove the non-ideal components, such as organic acids, glial and asphaltenes etc. It also brings bleaching and deodorization effects. Often used adsorbents are clay, activated clay, diatomaceous earth, alumina, silica gel, activated carbon and the exchange resin. The temperature has a great impact on the adsorption efficiency, to increase temperature and lower viscosity can increase the adsorption rate.
Distillation: A method of separating according to the different boiling point of the compound. In the waste oil regeneration process, we can remove light hydrocarbons by distillation dehydration. Asphaltene, galatine, additives and other residues shall remain in the left residual solids which the base oil is produced and separated. Normally, distillation includes atmospheric distillation and vacuum distillation. Atmospheric distillation needs high oil temperature, while there are compounds in the oil likely to be damaged by high temperature. Therefore, vacuum distillation is more widely used.

Solvent Refining: Solvent refining is a process to get rid of impurities and non-ideal components by extraction. The solvent refining process in waste oil regeneration involves the use of a low-molecular-weight (LMW) hydrocarbon solvent to precipitate the relative high-molecular-weight (HMW) compounds or flocculated ash products and additives, as well as the use of polar solvents to extract aromatic hydrocarbons and polar materials. Propane refining is the first story in industrial production, It has a good performance to remove waste oil additives, metal salts, oxidation condensation products, gum, asphalt, etc..
Neutralization: Neutralization is a method using inorganic base to neutralize with acid inside the oil before refining or neutralizing the acid oil after sulfuric acid refining. Salt or soap and water are produced. Commonly used inorganic bases include sodium hydroxide, sodium carbonate, sodium phosphate and hydrated lime etc.. Organic amines (mainly used for waste engine oil) are more diverse, from relatively low molecular weight ethylamine to higher octadecylamine, aliphatic amines, aromatic amines, alkanolamines, and polyamines. Generally, alkali liquor is to be added in the process. Alkali concentration, temperature principle: generally in ensuring emulsification does not occur, try to choose high concentrations and low temperature conditions. Neutralization is commonly used in combination with water washing, demulsification, and adsorption.
Emulsification and Demulsification: Alkaline washing and washing process often encounter emulsification with which the oil and water will form an emulsion. Generally in pre-alkaline washing process, due to the existence of alkaline earth metal, naphthenate or sulfonate and colloidal , it forms a “water-in-oil” emulsion; In process of neutralizing sulfuric acid refined oil, due to existence of sodium, sodium sulfonate and fatty acid sodium ,it forms a “oil-in-water” emulsion. There are two main ways of emulsion breaking, thermal demulsification and chemical demulsification. The efficiency of thermal demulsification depends on the temperature, the higher the temperature the higher the efficiency. Generally, the light emulsification degree can be efficiently decreased by thermal demulsification method in the process of waste oil treatment. For the more serious emulsification, which often requires chemical demulsification, for the water-repellent emulsion, often need to add sulfuric acid, dodecyl sulfonic acid or sodium naphthenate, etc .; for aqueous favoring emulsion, often joined with cationic inorganic Compounds, such as hydrochloric acid, Sodium Chloride, calcium chloride.
Flocculation: Flocculation is a way to gather or larger the suspended solids in the oil in order to ease the settlement for the purpose of solid-liquid separation. Many waste lubricants contain a clean dispersant agent, resulting in a number of solid particles colloidal steadily dispersed in the oil. The particles in the dispersant agent are small, and not easy to be separated by filtration and sedimentation or centrifugation. Therefore, flocculation is one of the most effective methods to remove solid particles before distillation process, which is more effective than mechanical separation. Flocculation is generally used in conjunction with the mechanical methods mentioned above. Flocculants are divided into inorganic and organic flocculants. Inorganic flocculant can be acid, alkali or salt. Organic flocculants including phenyl, diethanolamine, cationic polymer fatty acid salt, alkyl quaternary ammonium salt, arylamine etc.. Organic flocculants price is relatively expensive, it’s better to use in combination with inorganic flocculants.
Hydrogenation: To refine waste oil in high temperature and pressure with catalyst. Oxygenated compounds in waste oils (mainly carboxylic acids, carboxylates, aldehydes, ketones, alcohols, phenols, and peroxides, etc. produced during the oxidation of waste oils) Sulfur compounds (additives or contaminants introduced) Halogenated compounds (Additive or contamination) Nitrogen-containing compounds (from base oils or additives) and olefins (from base oils or high temperature applications), etc. can be refined by the hydrogen technology. Hydrogenation is usually the last step in the regeneration process. In the environment of high temperature and high pressure, the leakage of hydrogen from the hydrogenation device in the plant would mix with air and easily lead to an explosion. Moreover, the design, installation, operation, and maintenance of hydrogenation unit have strict requirements. Therefore only for a large-scale waste oil recycling plant may be possible to go to the hydrogenation process.

Recovery process of waste lubricating oil 02

Kitchen Waste Feature

What is kitchen waste?
Kitchen waste is the most important type of food waste. The Beijing Municipal Administration Commission Kitchen Waste FeatureNo. 5 of 2005, “Administrative Measures for the Collection and Transportation of Kitchen Waste in Beijing” defines the kitchen waste: Garbage refers to wastes such as food residues, residual liquids and waste oils produced by hotels, restaurants, restaurants and institutions, military units, colleges and universities, and enterprises during food processing, catering services, and unit feeding. According to statistics from the Institute of Solid Waste Pollution Control and Resource Reconstruction of Tsinghua University, 60 million tons of kitchen waste is produced every year in China’s cities.

With the improvement of people’s living standards, the amount of kitchen waste generated has increased year by year [4]. At present, there are problems such as “ditch oil” and “garbage pig” that are well known in China, and they are all products of informal disposal of kitchen waste. How to make good use of kitchen waste has become a hot spot in contemporary scientific research.

◆Features of Kitchen Waste

(1) rich in organic substances such as starch, fat, protein, cellulose, nitrogen, phosphorus, potassium, calcium and various trace elements, toxic and harmful chemicals (such as heavy metals) are low in content and rich in nutrients, and are rich resources for making animal feed and organic fertilizer;

(2) The rate of decay and metamorphism is fast, and it is easy to carry the pathogenic bacteria: foot-and-mouth disease, Salmonella, Toxoplasma gondii, and swine fever.Direct use and inappropriate handling can cause the spread and infection of pathogens;

(3) The swill oil and the waste oil are processed into food oil, which directly harms human health.

(4) Under high temperature conditions, the decay rate is fast.

(5) The water content (70%-90%), oil content (1%-5%) and NaCl (1%-3%) are much higher than foreign countries. Catering waste varies by location, location, and season. Typical Korean food waste ingredients contain 48.4% carbon, 6.9% nitrogen, nitrogen ratio of 7.0, and water content of 80.3%. From the chemical composition of view, there are startch, cellulose, protein, lipids and inorganic salts, among which organic components are the main creatures.

How To Do Waste Crude Oil Recycling

The oil industry produces large quantities of solid and semi-solid wastes called oily sludge. Oily sludge usually contains water, sand, oil, grease,How To Do Waste Crude Oil Recycling 02 organic compounds and metals. Due to the diversity of crude oil quality, the differences arising from the different processes used in the oil-water separation process, the leakage in the industrial process, and the mixing with a variety of other existing oily sludge, the composition of the oily sludge has a variety of difference.

These oily sludge can be produced in several steps of oil production and refining, for example in oil-water separation and settling at the tank bottom..

The high stability of the oily sludge is due to the oil adsorbed on the solid particles, resulting in the formation of the protective layer. The stability is enhanced by the presence of polar fractions in the oil, especially resins and asphaltene, which also contribute to the high viscosity of these sludge. In addition, the protective layer is conducive to the production of microorganisms, but also for the diversity of microbial communities to provide a breeding cover, thereby causing environmental corrosion, which is reflected in each use of storage tanks, the storage tank will be corroded. Oily remnants accumulate in the petroleum industry and cause serious environmental problems.

This type of sludge is considered hazardous waste in many countries because it contains high concentrations of toxic components and therefore requires proper management. Recycling of the waste crude oil in such oily sludge is an ideal treatment because it not only recovers valuable energy, but also minimizes the concentration and total amount of hazardous waste. We benefit from the recovered oil and at the same time reduce the cost for the residual further disposal treatment.

There are various ways to recycle the waste crude oil. The cost and production efficiency mainly become the points when user choose their own. However, the combination of chemical additives, heating, and physical separation has undoubtedly become a mainstream choice in current processing methods, because of its mature technology, the equipment used is simple and easy to operate. Through different temperature configurations, chemical additives, core equipment, and even fine-tuning of the entire process, make it can adapt to different area of various sludge oil recovery.

Step 1: Pretreatment

In the waste treatment process, whether it is reduction, recycling or harmless treatment, after the initial experimental analysis of waste, in order to meet the next stage of the entire process requirements, will be pre-treatment of materials. Such pretreatment methods can be dilution, sedimentation, sieving, heating, demulsification, gel breaking, viscosity reduction and so on. Of course, in the treatment of certain special oily sludge, such as some heavy crude oil sludge , aging sludge, adding a certain proportion of light crude oil for dilution, in order to make it easier for the next separation, will achieve surprising results . In the initial classification of the waste sludge, according to the size of oil particles inside the sludge and the proportion of the solids, mechanical vibrating screen or roller screen to be chosen. According to the oil content of the sludge, sludge viscosity, different crude oil condensate point , we will choose different chemical additives to broken gel, breaking, and set the different heating temperature. As the entire process using pipeline transport, the main purpose of the pretreatment is to ensure the viscosity of oil sludge and liquidity suitable for the pumping process.

Step 2: Separation

After pretreatment, centrifugal separation is the most important part of the process. Due to the different density of the different physical phase, the different components will go through a specific orbit attribute to the centrifugal force. In general, the oily sludge components are divided into oil, water, solid. Separation equipment selection in the process should be based on the actual proportion of material components, and reduce the cost point of view , such as two-phase decanter centrifuge, three-phase decanter centrifuge, Disc separator and oil-water separator.

Step 3: Filtration

Taking the recovered crude oil quality into consideration, a filter system may be put into the process after the separation part. Or it’s even better to send the recovered oil to refinery plant for further purification process.

ZK separation is an experienced solution and equipment provider on oilfield waste management. The company has been dealing with oily waste including cured oil, cooking oil, engine oil, lubrication oil for more than 16 years. The valuable practice on projects enhance the production performance for various working condition and different types of oily waste.

How To Do Waste Crude Oil Recycling 01

How To Separate Sand From Water

In the dredging of lakes, geothermal, drilling, piling, tunneling and other operations, how do we separate the sand and water we pumped?How To Separate Sands from Water 01

The separation of sand and water usually takes the following methods:

1. Natural sedimentation.

Because sand and water have a large density difference. By putting still for a long time, the sand in the water can be naturally settled and the upper layer of water can be pumped out to achieve the separation effect of sand and water. However, this method is relatively inefficient, and the separated sand still contains most of the water. If you require a high efficiency and a low moisture content of the sand, this method should not be used.

2. Filtration separation

Allow sand and water to pass through the filter or filter cloth quickly, and the sand is successfully intercepted on the other side of the filter to achieve separation of sand and water.

The equipment commonly used in this method includes a vacuum filter and frame filter press. The efficiency is high, but the filter cloth needs to be replaced frequently, and the cost of consumables is high. Moreover, the separation effect often depends on the particle size of the sand particles. When the sand particle size is too small, it is not easy to separate, usually it will block the filter holes, reduce the working efficiency of the equipment, and at the same time, the filter needs to be replaced regularly which resulting in large labor costs, and the working environment is also dirty. This method is not suitable for projects with large sand particle size distribution and large variations.

3. Centrifugal separation

Centrifugal separation is the use of high-speed rotating equipment that produces powerful centrifugal forces that tend to be thousands of times larger than their own weight.

By the action of centrifugal force, the sand and water are quickly separated and then discharged through a specific outlet to achieve the purpose of sand and water separation. The equipment commonly used in this method is: horizontal spiral discharge sedimentation centrifuge (referred to as: decanter centrifuge).

The use of decanter centrifuge for solid-liquid separation is highly efficient and can be operated continuously for 24 hours, with automatic feeding and automatic unloading. he separated sand has low water content and clear water, which can meet most project requirements.

At present, most centrifuges fabricated by manufacturers equipped with full-automatic control system, thus saving a lot of manpower. It is widely used in field wastewater, piling wastewater, lake dredging, tunnel engineering and other fields.

How To Separate Sands from Water 02