DH series double roller granulator

The importance of powder granulating technology as one of the most important branches of powder particles processing treatment is increasingly clear with the demand of environment protection and improvement of automation of the production process. “Powder products will become granules” has become the necessary trend of powder-after-processing technology in the world. The significance of pellet strength processing to the powder product is embodied in the three main-areas:

DH series dry roll press granulator adopts dry rolling technology to compress the powdery materials with moisture content ≤ 5% into pieces or tablets, then going through the processes of breaking into granules and screening to make the lump materials into granules that meet the requirements of application. Dry roll press granulator mainly depends on the manner of external pressure to force the material going through the gap between two relatively turning rollers to compress into laminar particles. During course of roller pressing, the real density of materials can increase 1.5~3 times thus reaching certain demands of granular strength.

Working principle:

DH series dry roll press granulator machine adopts dry rolling technology to compress the powdery materials with moisture content ≤ 1% into pieces or tablets, then going through the processes of breaking into granules and screening to make the lump materials into granules that meet the requirements of application. Dry roll press pelletizer mainly depends on the manner of external pressure to force the material going through the gap between two relatively turning rollers to compress into laminar particles. During course of roller pressing, the real density of materials can increase 1.5~3 times thus reaching certain demands of granular strength. 

Features

◆Without any additives, dry powders are granulated directly.

◆Granular strength can be adjusted by adjusting the pressure of roller, control strength of final products.

◆Cycle operations to achieve continuous production.

◆High yield of finished products.

◆Materials are force to compress molding by mechanical pressure, without any additives, the product's purity is guaranteed.

◆Dry powders are granulated directly without follow-up drying process, the existing production process is easy to convergence & transformation.

◆Granular strength is high, compared with other granulating methods, the improvement soft bulk density are significant，especially for the occasion where increase the proportion of product accumulation.

◆A wide range of raw materials can be used, granular strength can be freely adjusted according to different materials.

◆Compact structure, easy maintenance, simple operation, short process, low energy consumption, high efficiency, low failure rate.

◆Control environmental pollution, reduce waste and powder packaging costs, and improve product transport capacity.

◆Feeding device adopts frequency adjustment control, high automation ,one can control multi-machine, has the features of low labor intensity and long term continuous operation, etc.

◆Major transmission components use high quality alloy material. Stainless steel, titanium, chromium and other surface alloys which greatly improved wear resistance, corrosion resistance, high temperature and pressure capabilities, so that this machine has one long service life.

Applied materials:

1.Fertilizers: potassium sulfate（SOP）, potassium chloride, the Russian red potassium, NPK fertilizer, ammonium chloride, potassium nitrate, Ammonium Phosphate Monobasic(MAP),Diammonium phosphate(DAP), ammonium sulfate, ammonium bicarbonate, cow manure plus sulfur, humid acid etc.

2.Powders: antioxidant,BROMOCHLOROHYDANTOIN, sodium cyanide, sodium dichloroisocyanurate, sodium TCCA, cyanuric acid, calcium hypochlorite, zinc oxide, lead oxide, potassium carbonate, carbonate strontium, calcium chloride, dicalcium phosphate, sodium metasilicate, sodium silicate, cryolite, aluminum fluoride, brake powder, rubber additives, silica, calcium aluminate, TSP, SSP, carnallite stone, phosphate rock, metal powder, fillers, feed additives, arsenic porphyrin insects, nicotinic acid, nicotinic acid amine, pharmaceutical intermediates, steel-making additives, melting agent, swelling, alumina powder, phosphogypsum, gypsum, benefication agent, environmental protection materials.etc.

Advantages:

• Advanced driving system Adopting increased double shafts output dedicated reducer and drum gear shaft coupling effectively protects the rolls and the main bearing from damage, increasing the driving efficiency and further improving the production of products.

• Optimized frame structure The new type frame designed through optimized calculation according to human engineering is equipped with a working platform at the top which has a large door structure near the rollers and which is convenient for the operators. It fully meets the requirements of the customers to reliability of the equipment safety and overhaul convenience.

• High efficient, durable alloy steel rollers The roller matrix is wholly forged with high quality alloy steel, which can widely adapt to all kinds of complicated material conditions. In the design of the wearing layer of the roll surface, have held the rules of the max. Mechanical stress effect depth according to the HZ contact theories and pure elastic theories assembled the materials of tear-proof layer, interlayer, wearing layer, arranged hardness, and improved heat treatment process scientifically so that the crack-proof and wearing properties have been improved greatly. The finally case-hardened patterns of the roll surface after repeated tests, compared and profiting from the technical improvement of other components (such as the feeding unit) can make the pull-in angle of the materials more equipoise, stable, and can effectively remove the axial action of the rolls at the same time to make the equipment working more stable.

• Bran-new feeding unit Bran-new designed feeding unit equipped with regulating valve plate can conveniently realize on-line adjustment. The increased air expansion chamber can make the air carried in materials discharged smoothly and improve the occlusion of the materials between the rollers. The technical improvement of the feeding unit also results in the improvement of the patterns of the roller surface directly.

• Simple, safe hydraulic system In the design of the hydraulic system, we do not only consider it as the source of proving power, but also make it having the function of protecting the equipment. We designed multiple automatic protecting functions, and the optimized hydraulic system makes the motion flexibility of the dynamic rollers more strong and be able to reject the iron lumps mixed in unexpectedly and protect the equipment to run safely. Modularized and integrated design of the hydraulic system does away with the cumbersome, redundant pipelines. It takes less area and makes the whole equipment look simple, beautiful and highly efficient.

• Intelligent control system Roller press use on-line control operation, can set the device operating parameters easily & intuitively, on-line detection, control equipment operating status, to provide operator decision-making information. With its help, roll granulator work more stability.

• High-efficient crushing &granulating system The crusher is divided into two levels, can crush the materials of block twice, and has three rooms, greatly increases the broken area, so this crusher improve crushing efficiency & rate of final products.

• Superior screening system This machine has the advantage of small vibration, low noise, and low strength requirements, and combine the advantages of circular motion, elliptical motion, and reciprocating linear motion, and has cleaning devices for screen surface, so it has large production, high screening efficiency , small power consumption, flexible installation, convenient for screening.

Unit structure:

1)  Pre-feeder: Equipped with mechanical vibrating feed hopper with automatic control and timing vibration

2)  Quantitative feeder: Adopts frequency conversion adjusting speed to ensure the feeding accuracy.

3)  Force-feeding screw hopper: It is composed of variable frequency motor, cone helix, stirring knife tooth and cone feeding hopper with visual glass window as well as feeding mouth assemblies and so on. Its function is to further achieve degassing and perform pressure feeding.

4)  Flaking machine: it is composed of left and right fixed bearing seats, frame structure, two alloy steel rollers, two hydraulic oil cylinders, electric automatic pump station as well as hard tooth surface dedicated reducer and main driving motor.

5)  Crushing & granulating machine: it is composed of cutting-up box, cutting-up main shaft and special rotating cutting blades and the main shaft is driven at high speed by the motor to break the extrusion forming materials and dress into pellets.

6)   Vibration screen: It is equipped with screen block-proof device and convenient to clean the screen. The broken pellet and powder materials from the breaking and dressing machine are divided into pellet product and recycling powder.

7)   Material return auger: It sends the unaccepted powder material returned from vibration classification screen to the feeding elevator.

8)   Bucket elevator: Upper and lower sprocket use assembly structure for the transportation of materials.

9)   Control cabinet: It is composed of the electrical components such as electric control box, frequency conversion controller, ammeter, voltage meter, light, button switches, voltage switch and so on. All the electrical equipment is controlled and operated concentratedly. 

Example of raw materials:

Note: Rolled sheet output, finished product outputs are just for reference and the screen is determined according to the nature of materials.

DH1050 three sets of production flow chart

This process is DH650 and the following models of the conventional process

A brief introduction to the whole line project process

Granulation line working principle, I will introduce you the whole granulating process (it takes DH650 for example):
1). We use mixer to the raw material for more uniform feeding.---Mixer
2). We use bucket elevator lift the material up to the silo.----Bucket elevator and Silo
3). The DH650 granulator compress the raw material by double rollers, it mainly depending on the mechanical pressure to compress the dry powder, so the hardness of granular is very high.---------DH650 granulator (including three parts: dosage screw feeder, forced feeder and flaking machine.)
4). Then we get the bar shape products, just as following:

So we need a crusher to crush the bar shape products into 2-4mm irregular granules.----Crusher (you can decide the size of granules, we will design the size of crusher mesh.)
5). Finally, we will use rotary screen to sieve the final products, the unqualified products, such as dust, big granular and very small granular will be recycled for the next time granulation process. You will get the qualified 2-4mm irregular shape granules successfully.--------Rotary Screen
6). Next we use the second time rotary screen, the purpose is we want to get better result of irregular shape granules after second time screening, the appearance of irregular shape granular will looks more beautiful. -------Second Time Rotary Screen (if you don’t need this, you can delete this process.)
7). The last step is automatic packaging machine. This machine will help you pack the final granular into bags. ----Automatic Packaging Machine
8). Workshop dusts mainly come from the crusher, screening and discharging port of bucket elevator, in order to effectively remove the dust, this process uses two stages of dust removal. A cyclone dust collector is used to remove the larger particle dust, and then the bag dust filter is used to remove the residual dust. The dust from the dust collector will return to the granulation process by scraper conveyor.------ Dust collector.
 

 This process is DH850 and the above model of conventional process

Technological innovation

 DH series of new dry process roller granulator as the core single machine equipment of the granulation production line, its electrical control part is divided into 2 parts: power start stop part and closed loop control part. At present, most of the granulation machines on the market are still using the original control method, that is, according to the actual situation of the material on the spot, we always pay attention to the change of the current and adjust the speed of the feed motor and rolling mill manually, so that the granulator keeps dynamic balance in the process of operation. After years of production experience and users' use feedback, we have developed a new type of control mode through the production experience and the users' use feedback. The control system of the granulator control system itself will be monitored and changed through the formation of a new type of control mode, which consists of a closed loop control system between the control quantitative feeder and the inverter of the rolling host. The control system of the granulation machine itself will be monitored and changed through the change of the control system. The PID of the frequency divider itself controls the speed of the quantitative feeding machine and the rolling host to keep the dynamic work balance at the best position at all times, so that the working current of the roller is kept steady and uniform at the set work value, and the feed can also adjust the rotational speed at any time, but the granulation from the roller. The machine is always in the best state of work. At the same time, this system also has manual control and automatic control mode switching, so as to achieve the effect of flexible and convenient operation. At present, the newly developed DH1050 will soon be put into use, and the output will reach 10 tons per hour.

Clients using site: 

     Various control systems (common electric cabinet, industrial control computer, PLC and large DCS system)

   Using computer technology and industrial controller hardware and software to configure each other to achieve highly automated and intelligent production. It can ensure the orderly and safe production of production, monitor, operate and manage the production process centrally, improve the production efficiency, stabilize the product quality and management level.