A good fermenter device and composition
(1) should have a tight structure
(2) good mixing characteristics of the liquid
(3) a good rate of mass transfer phase heat transfer
(4) with supporting and reliable detection, control instrumentation Beer Fermentation Equipment - History of the development of the fermenter The first stage: before 1900, it is the first stage of the modern fermenter. The prototype of the modern fermenter, it has a simple temperature and heat exchange instruments.
The second stage: 1900-1940, the emergence of 200m3 steel fermentation tanks, in the baker's yeast fermentation tanks began to use air distributor, mechanical stirring began to be used in small fermentation tanks.
Third stage: 1940-1960, mechanical stirring, ventilation, aseptic operation and pure seed culture and a series of technologies began to improve, the fermentation process parameters detection and control has appeared, steam sterilization resistant online continuous measurement of pH electrode and dissolved oxygen electrode, computer began to control the fermentation process. Fermentation product separation and purification equipment is gradually commercialized.
The fourth stage: 1960-1979, mechanical stirring and ventilated fermenter volume increased to 80-150 m3. due to the need for large-scale production of single-cell protein, and the emergence of the pressure cycle and pressure injection type of fermenter, which can overcome some of the gas exchange and heat exchange problems. The computer began to be widely used in the fermentation industry.
The fifth stage: 1979 to the present. The rapid development of biological engineering and technology, to the fermentation industry puts forward new issues. Thus, large-scale cell culture fermenter came into being, insulin, interferon and other genetically engineered products on the road to commercialization. Beer fermentation equipment - the characteristics of the fermenter (1) fermenter and other industrial equipment is the outstanding difference between the high requirements of the pure culture, almost to a very harsh degree. Therefore, the tightness of the fermenter, the operation of a high degree of reliability is a significant feature of the fermentation industry.
(2) modern fermentation industry in order to obtain greater economic benefits, fermentation tanks tend to be more large-scale and automation development. In the automation of fermentation tanks, as a parameter detection of the eye such as pH electrode, dissolved oxygen electrode, dissolved CO2 electrode, etc. online detection in foreign countries has been quite mature. Fermentation detection parameters are still limited to temperature, pressure, air flow and some other most conventional parameters. Beer fermentation equipment - the types of fermentation tanks most commonly used in the fermentation industry is the ventilated stirred tank. In addition to vented stirred fermenters, other types of fermenters such as: airlift fermenters, pressure cycle fermenters, fermenters with ultrafiltration membranes and so on.
Typical fermentation equipment: seed preparation equipment, the main fermentation equipment, auxiliary equipment (aseptic air and media preparation), fermentation broth pretreatment equipment, crude product extraction equipment, product refining and drying equipment, effluent recycling, utilization and treatment equipment fermentation tank process operating conditions
1. Temperature: 25 ~ 40 ℃.
2. Pressure:0～1kg/cm3(gauge pressure).
3. Sterilization conditions;Temperature:100～140℃,Pressure:0～3kg/cm3(gauge pressure).
4. pH:2～11.
5. Oxygen demand:0. 05～0. 3kmo1/m3-h.
6. Aeration:0. 3～2VVM.
7. Power consumption:0. 5～4kW/m3.
8. Fermentation heat:5000～20000kcal/m3.h. Beer Fermentation Equipment-Types of Fermenters 1. Classified according to microbial growth and metabolic needs
Aerobic:Antibiotics, enzymes, yeast, amino acids, vitamins, and other products are carried out in an aerobic fermenter; strong ventilation and agitation are required, with the aim of increasing the mass transfer coefficient of oxygen in the fermentation broth. Anaerobic: Acetone butanol, alcohols, beer, lactic acid, etc. are carried out in anaerobic fermenters. Aeration is not required.
2. Classification according to the characteristics of the fermenter equipment
Mechanical stirring and ventilated fermenter: including circulating, such as Wood type fermenter, Venturi fermenter, as well as non-circulating ventilated fermenter and self-priming fermenter. Non-mechanical stirring and ventilated fermenters: including circulating gas lift, liquid lift fermenters, as well as non-circulating vent and jet fermenters. These two types of fermenter is to use different means to make the fermenter gas, solid, liquid three-phase fully mixed, so as to meet the microbial growth and product formation of oxygen demand.
3. Classification by volume
Generally speaking, it is considered that 500L or less is the laboratory fermenter; 500-5000L is the pilot fermenter; 5000L or more is the production scale fermenter. Closed anaerobic fermentation tank
The requirements for this type of fermenter are: can be closed; can withstand a certain pressure; cooling equipment; tanks to minimize the device to eliminate dead ends, easy to clean and sterilize.
Alcohol and beer belong to the smoky fermentation products, its fermenter because it does not need to pass into the expensive aseptic air, so in the amplification of the equipment, manufacturing and operation, are much simpler than the good gas fermentation equipment.
It's volume is often greater than 50m3, H:Dt=1-2, the tank's upper and lower are conical.
The upper part has material mouth, cooling water mouth, CO2 and gas outlet, manhole and pressure gauge opening.
Temperature control is by a combination of snake pipe inside the tank and direct water spray on the outside wall of the tank, and the discharge pipe is at the bottom of the tank.
A, alcohol fermentation tank
Yeast will be converted to sugar alcohol high conversion rate conditions
(1) to meet the necessary process conditions for yeast growth and metabolism
(2) a certain biochemical reaction time
(3) timely removal of the biological heat will be released in the process of biochemical reaction
Structural requirements for the alcohol fermenter: to meet the process requirements, and conducive to the heat of fermentation. Process requirements, conducive to the discharge of fermentation heat, structurally favorable to the discharge of the fermentation liquid, conducive to equipment cleaning, maintenance and equipment manufacturing and installation of convenient issues.
Beer fermentation equipment - development trend In recent years, beer fermentation equipment to large-scale, outdoor, joint direction, so far, the use of large fermentation tank capacity has reached 1500 tons. The purpose of large-scale is:
(1) due to large-scale, so that the quality of beer homogenization; due to the number of tanks of beer production to reduce the number of tanks, so that the production of rationalization, reducing the investment in major equipment.
Changes in fermentation vessel materials. Evolution from pottery to wood - cement ---- metal materials. Now beer production, the latter two materials are in use. Most of our beer fermentation vessels are reinforced concrete tanks with paint inside, and stainless steel is generally used for new large vessels.
(2) open fermentation vessel to closed type change.
Small-scale production, generally open, the management of fermentation, foam form observation and mash concentration determination is more convenient. With the expansion of the scale of beer production, the fermentation vessel is large and closed type. The biggest problem in switching from open to closed fermentation is the handling of the bubble cap that is brought to the surface by the bubbles during fermentation. The bubble cap can be separated by the suction method.
(3) Evolution of the closed vessel.
Originally, it was a closed fermentation tank with a bow-shaped lid on top of an open rectangular container; with technological innovation transitioned to a horizontal cylindrical fermenter made of steel, stainless steel or aluminum. Later appeared is vertical cylindrical cone bottom fermenter. At present, the use of large fermenters are mainly vertical tanks, such as Naitan tanks, joint tanks, Asahi tanks and so on. Due to the increased capacity of fermentation tanks, cleaning equipment and devices are also required to have a great improvement, most of the CIP automatic cleaning system. Beer pre- and post-fermentation equipment and calculations. Beer fermentation equipment - before and after fermentation equipment (a) before the fermentation equipment
Traditional before the fermentation tank are placed in the fermentation chamber, most of the fermentation tank for the opening type. Before the fermentation tank can be made of steel plate, commonly made of reinforced concrete, but also brick, outside the cement fermentation tank. The form is mainly rectangular or square. Before the fermentation tank to be coated with a special coating as a protective layer. The use of unsaturated polyester resin, epoxy resin or other special coatings are more widely used, but not yet fully in line with the low-temperature fermentation of beer corrosion requirements.
The bottom of the former fermentation tank is slightly inclined, conducive to wastewater discharge from the bottom of the tank at 10-15cm, extends a tender beer release pipe in order to maintain the low temperature of the mash in the fermentation tank, the tank is equipped with a cooling snake tube or row of pipes. The cooling area of the former fermentation tank, according to experience, the following beer fermentation to take each cubic meter of fermentation liquid is about 0. 2 square meters of cooling area, the snake tube into the 0-2 degrees of ice water. Pay attention to the discharge of CO2 to prevent poisoning.
Post-fermentation equipment
Mainly complete the tender beer continues to ferment, and saturated with carbon dioxide, promote the stabilization of beer, clarification and maturation.
According to the process requirements, the storage room should maintain a lower temperature than the pre-fermentation room, the general requirements of 0-2 ℃, special products require to reach -2 ℃ or so. The post-fermentation process has low residual sugar and mild fermentation, so there is no need to install a cooling snake tube in the tank. The building structure and insulation requirements of the wine storage room can not be lower than the pre-fermentation, the maintenance of indoor low temperature, is to borrow the indoor cooling pipe or pass into the cold air circulation and get. Post-fermentation tank is a metal cylindrical closed container, there are two kinds of horizontal and vertical. Most factories use the horizontal type. The fermentation process needs saturated CO2, after the fermentation tank should be made of pressure resistance 0.1-0.2MPa gauge pressure container. After the fermentation tank tank body is equipped with manhole, sampling valve, in and out of the beer receiver, discharge carbon dioxide receiver, compressed air receiver, thermometer, pressure gauge and safety valve and other ancillary equipment. The material of post-fermentation tank is generally made of A3 steel plate, and the inner wall is coated with anti-corrosion layer. The wine storage tanks are all placed in a heat-insulated wine storage room to maintain a certain post-fermentation temperature. Adjacent to the wine storage room, there is an insulated and warmed operation channel, in which the regulation and operation of the post-fermentation process is carried out. The walls separating the wine storage room and the passageway are equipped with a certain diameter and number of glass peepholes to facilitate observation of the interior of the post-fermentation room. The channel is kept at room temperature, and the pipes and valves for opening the fermentation liquid are connected to the channel. Beer fermentation equipment - new beer fermentation equipment 1. cylindrical body conical bottom fermentation flare
Circular simplified body conical bottom vertical fermenter (referred to as conical tank), has been widely used in the top or bottom fermentation beer production. The conical tank can be used alone for pre-fermentation or post-fermentation, but also can be combined in the tank before, after fermentation (a tank method). The advantage of this equipment is that it can shorten the fermentation time, and has the flexibility of production, so it can be suitable for the production of various types of beer requirements.
Features of the equipment
This equipment is generally placed outdoors. Sterilized fresh wort and yeast from the bottom into the tank; fermentation is at its peak, the use of all the cooling jacket to maintain the appropriate fermentation temperature. Refrigerant mostly glycol or alcohol solution, can also use ammonia (direct evaporation) as refrigerant; CO2 gas from the top of the tank. Tank body and lid are equipped with manholes, the top of the tank is equipped with pressure gauges, safety valves and glass mirrors. In the bottom of the tank is equipped with purified CO2 filling tube. The tank body is equipped with a sampling tube and a thermometer receiver. The outside of the equipment is wrapped with a good insulation layer to minimize cold loss.
Advantages:
(1) It is low energy consumption, the pipe diameter used is small, and the production cost can be reduced.
(2)The yeast eventually deposited at the bottom of the cone can be opened and the valve at the bottom of the cone can be opened to discharge the yeast out of the tank, and some of the yeast is kept for the next time to be used.
Factors affecting the cost of fermentation equipment
Fermentation equipment size, form, operating pressure and the required cooling workload. The form of the vessel mainly refers to the surface area required per unit volume, expressed in m2/100L, which is the main factor affecting the cost.2. General-purpose tanks
Used in multi-tank and one-tank production. Therefore, it is suitable for a variety of needs, so it is also called the type of tank for general-purpose tank.
Structure: the main body is a cylinder, is composed of seven layers of 1. 2m wide steel plate. The total surface area is 378m3 and the total volume is 765m3.
The combined tank is composed of a thin-shelled vertical cylinder with a manhole, an arched top and a conical bottom with sufficient slope to remove yeast. The conical bottom can be similar in form to that of a wheat leaching tank. The foundation of the combined tank is a reinforced concrete cylinder with an outer wall about 3m high and 20cm thick. The shape of the upper part of the cylindrical wall of the foundation is determined according to the slope of the tank bottom. There are 30 iron anchors evenly sub-buried into the cylinder wall and welded to the tank. Between the cylinder and the bottom of the tank is filled with strong and sturdy cement mortar, leaving 25. 4cm thick hollow layer between the filler and the bottom of the tank for insulation.
3. Asahi tank
Front fermentation and post-fermentation in one large outdoor fermenter Asahi tank is made of 4-6mm stainless steel plate with a sloping bottom cylindrical fermenter. The ratio of height to diameter is 1:1-2:1, and there is a cooling jacket outside, which surrounds the tank body and the bottom of the tank. The outside is insulated with Styrofoam and the inside is equipped with a movable drain pipe with a rotating shaft, which is used to drain the liquor and has the function of keeping the CO2 content in the liquor homogeneous.
Features of the Asahi Tank
The Asahi tank has the same function as the conical tank, but the production process is different.
(1) Use of centrifuge to recover yeast
(2) Use of thin plate heat exchanger to control the fermentation temperature
(3) Use of circulating pump to pump the fermentation liquid out and send it back.
Advantages:
The combination of the three devices with each other solves the problems of controlling the fermentation temperature and yeast concentration before and after the fermentation, and accelerates the maturation of the yeast. The use of yeast centrifuge to separate the yeast of the fermentation liquid can solve the shortcomings of the slow sedimentation of yeast to utilize the weak cohesive yeast for fermentation, increase the contact time between the yeast and the fermentation consistency, and promote the reduction of acetaldehyde and diacetyl in the fermentation liquid to reduce its content. Beer Fermentation Equipment - Types of Continuous Fermentation Tanks for Beer 1. Two agitation tanks and a yeast separation tank are connected in series, the wort stream with hops added is added to the first agitation tank, and after fermentation, the matured beer flows out of the separation tank. This process has reached a daily production of 100m2.
2. By several height 6 ~ 9m tower fermentation tanks connected in series, with some additional yeast separation and beer storage equipment.
There is another by the main fermentation tower and a fermentation tower, the fermentation cycle of 40, 50 hours, continuous fermentation for two months, all economic indicators are better than the batch method.
Acetone - butanol fermentation tank
Production of acetone, butanol fermentation tank than alcohol fermentation tanks, tanks need to withstand high pressure, the tank wall is thicker, made of steel plate. The top and bottom of the tank are made of spherical head, the surface inside the tank is flat and smooth, no internal parts, and the tank is cooled by surface spraying. Seed tank adopts jacket cooling. First, mechanical stirring fermenter
Mechanical stirring fermenter is one of the common types of fermentation plant. It is the use of mechanical agitator, so that the air and mash fully mixed to promote the dissolution of oxygen in the mash, in order to ensure that the microbial growth and reproduction, the oxygen needed for fermentation.
Beer fermentation equipment - the structure of the fermenter 1, tank
2, agitator and baffle plate
3, defoamer
4, couplings and bearings
5, speed changer
6, air distribution device
7, shaft seals
8, cooling device
Tank
Tank
The tank
is composed of a cylindrical body with a large diameter and a small diameter.
Welded by the cylinder and oval or disc-shaped head, the material is carbon steel or stainless steel, for large fermentation tanks can be lined with stainless steel plate or composite stainless steel made of stainless steel lining with a thickness of 2-3 mm. In order to meet industrial requirements, operating under a certain pressure, empty or real consumption, the tank is a pressurized container, usually sterilized at a pressure of 2.5 kg/cm2 (absolute pressure).
Stirrer
Stirrer has flat-blade type, curved-blade type, arrow-blade type three kinds of its role is to break up the air bubbles, so that the oxygen dissolved in the mash, from the degree of stirring to the flat-blade turbo is the most intense, the power consumption is also the largest, curved-blade followed by arrow-blade is the smallest. In order to disassemble easily, large agitator can be made into two halves, bolted together as a whole.
Types of stirring paddles for general-purpose fermenters
(1)The most widely used stirring paddle for general-purpose fermenters is the flat-blade turbine stirring paddle, and most of the ones used domestically are of the six-flat-blade type, and the proportion of the size of each of its parts has been standardized. This kind of stirring paddle has a large circulating liquid delivery capacity and high power consumption. Therefore it is especially suitable for filamentous bacteria fermentation.
(2) Marine screw stirrers, which have a more intense axial flow than turbine paddles, but the oxygen transfer efficiency is low.
(3) Vibratory mixers, which, while providing higher oxygen transfer efficiency, have lower shear.
(4) Multi-rod stirring paddles, which have been used in fermenters for viscous, filamentous Streptomyces fermentations. This type of stirring paddle has better shear dispersion capacity and lower power consumption, and the power change is much smaller relative to the turbine paddle during the whole fermentation process.
(5) The gas introduction agitator, which is composed of a hollow stirring paddle mounted on a hollow stirring shaft. The stirring paddle has at least one opening exposed to the liquid. As the stirring paddle rotates, the pressure in the opening is subsequently reduced, allowing the introduced gas to flow down the stirring shaft. It is adapted for low viscosity fermentation liquids.
Anti-foaming device
There are two ways of defoaming: one is to add chemical defoamer to eliminate foam, but high concentrations of chemical defoamer will inhibit fermentation, so you can't add too much; the second way, that is, mechanical defoaming. Mechanical defoaming devices are mainly four kinds.
One is the serrated defoaming paddle. It is installed on the top of the tank, high above the liquid level, fixed on the mixing shaft, with the rotation of the mixing shaft, constantly breaking the foam.
The second is a semi-closed turbo defoamer, which is developed and improved by the former, the foam can be broken directly by the turbine or thrown out by the turbine impact on the tank wall and broken.
Third is the centrifugal defoamer, they are placed on the top of the fermenter, the use of high-speed rotation of the centrifugal force generated by the foam broken, the liquid is still returned to the tank.
The fourth is the scraper type defoamer, it is installed in the fermenter exhaust port, the foam from the gas-liquid inlet into the high-speed rotation of the scraper, scraper speed of 1000-1450rpm, the foam is quickly broken, due to the role of centrifugal force, the liquid phi thrown to the shell wall, return to the tank, the gas is discharged by the vapor hole.
Baffle
The role of the baffle is to change the direction of the liquid flow, from radial flow to axial flow, prompting the liquid to turn fiercely, increasing dissolved oxygen. Usually, the width of the baffle is taken as (0.1-0.12)D, and 4-6 pieces can be installed to meet the condition of full baffle. The so-called "full baffle conditions" refers to a certain speed and then increase the tank accessories while the shaft power remains unchanged. To achieve the full baffle conditions must meet the requirements of the following formula:
D-tank diameter (mm)
Z-number of baffles
W-width of the baffle (mm)
Vertical columns, rows of tubes, can also play the role of the baffle, so the general has a cooling columns or rows of fermentation tubes or rows of tubes. Cooling columns or rows of fermentation tanks do not have another baffle. (But when the cooling pipe is a coil, there should be a baffle.) The length of the baffle is from the liquid surface to the bottom of the tank. The distance between the baffle and the wall of the tank is (1/5~1/9)W to avoid the formation of dead space and prevent the accumulation of materials and bacteria.
Couplings and bearings
Large fermenter stirring shaft is longer, often divided into two to three sections, with couplings to make the upper and lower stirring shaft into a solid rigid coupling. Commonly used couplings are drum-shaped and shell-shaped two. Small fermenter can use flange to connect the mixing shaft, the shaft should be connected vertically, the center line is correct. In order to reduce vibration, medium-sized fermenters are generally equipped with bottom bearings in the tank, while large fermenters are equipped with intermediate bearings, and the horizontal position of the bottom and intermediate bearings should be able to be properly adjusted. The bearings in the tank should not be lubricated, and liquid-lubricated plastic shaft tiles (e.g., asbestos phenolic plastic, polytetrafluoroethylene, etc.) should be used. The clearance between the shaft tile and the shaft is often taken as 0.4-0.7% of the shaft diameter to adapt to changes in temperature difference. Tank bearing contact at the journal is very easy to wear, especially the bottom bearing at the wear is more serious, can be in contact with the bearing at the shaft to add a sleeve, with the fastening screws and shaft fixed, so that only the wear of the sleeve and the shaft will not wear out, maintenance, as long as the replacement of the sleeve can be.
Variable speed device
The test tank adopts stepless variable speed device, fermentation tanks commonly used variable speed device has a triangle belt extension, cylindrical or spiral bevel gear reduction device, which to triangle belt variable speed transmission efficiency is higher, but the processing, installation precision requirements are high. Adopting variable pole motor for stage speed change, that is, in the peak oxygen demand using high speed, and in the stage that does not need high dissolved oxygen to reduce the speed appropriately. In this way, the fermentation yield is not reduced, while power consumption is saved. Higher degree of automation of the fermenter, the use of thyristor frequency conversion device, according to the dissolved oxygen meter continuous determination of the concentration of dissolved oxygen in the fermentation broth, and in accordance with the microbial growth of oxygen consumption and fermentation, automatically change the rotational speed at any time, such a device to further save the power consumption, and can correspondingly improve the fermentation yield, but the device is quite complex.
Air distribution device
The role of the air distribution device is to blow into the sterile air, and make the air evenly distributed. Distribution device in the form of a single tube and ring tube and so on. Commonly used for the single tube type, the mouth of the bottom of the tank right in the center, installed in the lowest block under the agitator, the mouth of the tank and the low distance of about 40mm, and the air dispersion effect is better. If the distance is too large, the air dispersion effect is poor. The distance can be adjusted appropriately according to the dissolved oxygen, the air from the distribution tube spray up, was broken into small bubbles by the stirrer, and fully mixed with the mash, increasing the gas-liquid mass transfer effect. Usually the air flow rate of the vent pipe is taken as 20 meters/second. In order to prevent the air blown into the blowpipe from directly spraying the bottom of the tank, accelerating the corrosion of the bottom of the tank, weld a piece of stainless steel reinforcement on the bottom of the tank in the lower part of the air distributor. Can extend the life of the bottom of the tank. Ventilation at 0. 02 ~ 0. 5ml/sec, the diameter of the bubble is proportional to the 1/3rd power of the air nozzle diameter. In other words, the smaller the diameter of the nozzle, the smaller the diameter of the bubble. Thus, the oxygen mass transfer coefficient is also the greater. But the actual production of ventilation are more than the above range, so the bubble diameter is only related to the ventilation, but not with the diameter of the nozzle.
Shaft seal
Shaft seal function: the top or bottom of the tank and the gap between the shaft to seal, to prevent leakage and contamination of bacteria. Commonly used shaft seal packing box shaft seal and end face shaft seal two kinds. Stuffing box shaft seal is made up of packing box, packing bottom bushing, packing gland and compression bolt to be composed of parts, so that the rotating shaft to achieve the effect of sealing. Installed in the rotating shaft and equipment between the components, its role is to prevent the working medium (liquid, gas) along the rotating shaft out of the equipment where the leakage of the cooling device
5M3 fermenters generally use jacket cooling. Large fermenter using tube cooling (four to eight groups). With jacketed fermenter tank wall thickness should be calculated according to the external pressure [i.e., 3.5Kg/cm2 (absolute pressure)] jacket set up a spiral piece of guide plate to increase the heat transfer effect, while the tank body to play a reinforcing role. Cooling column tube is very easy to corrode or wear perforation, preferably made of stainless steel. Beer fermentation equipment-standard general-purpose fermenterEdit General-purpose fermenter is the most widely used equipment for deep aerobic culture.
In industrial production, especially in the pharmaceutical industry, the most widely used is the universal fermenter. This fermentation around both mechanical stirring device, and compressed air distribution device. The stirring shaft of the fermenter can be placed either at the top or at the bottom of the fermenter, with a height-to-diameter ratio of 2:1-6:19 Important factors are the oxygen transfer efficiency, power input, mixing quality, the form of the stirring paddle and the geometric proportions of the fermenter, etc. The stirring shaft of the fermenter can be placed either at the top or at the bottom of the fermenter, with a height-to-diameter ratio of 2:1-6:19.
Self-priming fermenter
The main differences between it and general-purpose fermenter are:① there is a special agitator, the agitator consists of a rotor and stator; ② there is no ventilation pipe.
The principle of suction of the agitator with rotor and stator:The rotor immersed in the fermentation liquid rotates rapidly, and the liquid and air are thrown to the outer edge of the impeller under the action of centrifugal force. At this time, the center of the rotor to form a negative pressure, the greater the rotor speed, the greater the negative pressure caused. As the rotor chamber is connected to the atmosphere, the air outside the fermenter through the filter is constantly being inhaled, and then thrown to the outer edge of the impeller, and then through the anisotropic impeller so that the gas and liquid uniformly distributed thrown out. The stirring of the rotor makes the gas-liquid form a strong mixing flow around the impeller, the air bubbles are crushed, and the gas-liquid is fully mixed.
Self-priming fermenter agitator
①Rotary wing blade self-priming agitator;
②Jet-type self-priming agitator;
③Self-priming agitator with rotor and stator.
Bubble tower fermenter
The tower fermenter is a long vertical cylinder, the cylinder is installed in the hole plate, some also installed in the tank agitator, the tank wall around the baffle. Similar to the batch of mechanical agitation fermentation tank, some of the top of the tower cross-section to expand, for to reduce the flow rate, to intercept the liquid entrainment of suspended solids. Fermentation liquid and air can be parallel flow, can also be counter-flow.
_The tank is characterized by: the tank is high, the height to diameter ratio of 6; hygromycin and other production equipment, the height to diameter ratio of 7. Due to the high level of liquid, air utilization rate is high, saving about 5% of the air, save about 30% of the power, but there is a sedimentation phenomenon at the bottom; temperature is high, it is difficult to lower the temperature.
The large-scale modern fermenter brings -series of insurmountable difficulties to STF. To be greater than 1000kW of mechanical agitation; a large number of cooling water and exclude heat; uniform distribution of energy; dissolved oxygen, carbon source and other nutrients and pH control.
Band-liter fermenter
Band-liter fermenter is also known as the air-stirred fermenter, without mechanical stirring, through the ventilation to play the role of stirring and supply of oxygen.
Features: simple structure, small cooling area, no stirring transmission equipment, large liquid filling coefficient, no need to add defoamer, easy maintenance, operation and cleaning, save power, reduce bacteria.
Working principle: external circulation air mixing tank is the air rising tube mounted outside the tank, the lower end and the bottom of the tank connected to the bottom of the tube with air nozzles, compressed air at a high speed of 250-300m / s spray, and rising tube mash contact, due to the gas-liquid mixture density is less than the mash in the tank, so the tube rises, the upper end of the tube is connected to the tank tangent line, the liquid enters by the tangent line in the tank to gyrating down, forming an intense cycle. intense circulation.
Liquid-lift fermenter
Liquid-lift fermenter is a fermenter in which the liquid is transported with the help of a liquid pump, while the gas is sucked into the fermenter at the nozzle of the liquid.
The nozzle is a special part of this type of fermenter and requires precision manufacturing.
Air Lift Fermenter
Air compressor is an important part of the air lift fermenter and its efficiency is determined by its form.
After the compressed gas enters the liquid through the air distributor, the bubbles formed initially are dispersed by the liquid turning violently, so the degree of dispersion of the bubbles is determined by the rate of power consumption.
(I) nozzle tower type
This is a two-phase nozzle and bubble column composed of the hair drunk tank, its ventilation efficiency is much better than the porous tube type or porous plate type.
This form of reactor is commonly used in wastewater treatment, such as in a 15,000m' activated sludge tank with 56 nozzles installed, which can convert 30,000kg of oxygen per day.
(ii)Nozzle tower circulation type
It uses two-phase nozzles as a ventilation device, with a high liquid circulation rate.
(iii)Spray-glass circulating type
It utilizes the jet force of the nozzles to draw in the gas and circulate the gas inside the tank to achieve a better effect of oxygen transfer.
The oxygen transfer effect.
(IV) Jet channel type
In this type of reactor, the liquid is accelerated in the elongated nozzle, so that the potential energy of the circulating liquid is converted into kinetic energy more effectively. The velocity of the liquid is greatest at the narrowest part of the nozzle and the static pressure is lowest. Air is drawn in and dispersed through the small holes or narrows, and the bubbles formed at the nozzle are carried to the bottom of the tank by the downward flowing liquid. At the end of the narrow tube, the gas moves upward and leaves the liquid to be discharged.
(v) Drip-bed type
The liquid is dispersed at the top of the tank and then drips downward through the immobilized microbial cells. Air is introduced at the bottom of the tank and flows in the opposite direction to the liquid. It has a wide range of applications in aerobic wastewater treatment.
(VI) Multi-stage tower recirculation type
This type of tank has a porous coil or sieve hole hair as the first stage separator. The liquid rest plane is controlled by an overflow pipe. (vii)Pipeline circulation type
Air is introduced into the liquid stream at a speed of 3-4m/s and then passed through a porous filter to be separated in a
cyclone separator and finally discharged from the system. This liquid stream passes through the pump and flow meter in one direction. With this there can be very high cell concentrations [up to t659 (dry weight cells)/L and high oxygen transfer rates. However the power input is also quite high. (H) Liquid fluidized bed type
In recent years, there are many research reports on the sinking bed biochemical reactor, which is mainly used in 3 areas
①enzymes fixed on a solid substrate;
②complete cells fixed on a solid substrate for pure culture;
③ biochemical fluidized bed is widely used in the wastewater treatment process.