In bridges, roads, high-speed railways and large-scale commercial concrete projects, the selection of batching plants directly determines the construction efficiency, the quality of finished concrete and the comprehensive operating cost of the project. At present, the mainstream equipment in the domestic engineering market is divided into two categories: dry batching plant and wet batching plant. There are essential differences between the two in terms of working principle, technical structure and adaptation scenarios, which are directly related to the efficiency, quality and economic benefits of engineering projects.
The official term of the dry mix concrete plant is “concrete dry batching plant”. The industry abbreviated as dry batching plant refers to the concrete production equipment without a center forced mixing host. It is only responsible for the accurate measurement and ingredients of sand, gravel, cement and other dry aggregates, and then unloads the dry material directly into the drum of the concrete mixing truck. Water is not added to the batching plant, but added to the tank truck during transportation or after arriving at the construction site. The tank truck completes the mixing during driving, which belongs to the highly specialized batching plant type in the engineering scenario.
The dry batching plant produces dry mixtures with a variety of products. Because no water is added, no hydration reaction will occur, so the storage time is long, usually up to 3 to 6 months. The sand used in the dry batching plant needs to be dried to ensure better grading and construction quality.
Its standardized working principle is in line with the technical specifications of the construction machinery industry: the system completes the precise ratio measurement of aggregates (sandstones), powders (cement, fly ash, mineral powder) and external agents through independent measurement units; after the measurement is completed, all kinds of materials are directly unloaded to the concrete transport tank through the conveying device; in the tank In the process of transporting the truck to the construction site, precisely metered water and liquid addients are added to the tank truck drum, and rely on the rotating stirring blades of the tank truck drum to complete the full mixing of materials, and finally form a finished concrete that meets the construction requirements.
From the point of view of technical positioning, the essence of the dry batching plant is a “precision batching system”. The core function is to complete the accurate measurement and transportation of materials, and transfer the mixing process from the station to the tank truck transportation link – this is the most core technical difference between it and the wet batching plant.
The dry batching plant products of the leading brand in the industry are typically represented by EPDAS Dry Mix Plant. Its technical design fully follows the high-standard industry standards. It has been systematically optimized for the measurement accuracy of the dry mixing process, the efficiency of material conveying, and the cooperative adaptability with the tanker, which can meet the Differentiated dry mixed production demand from small-scale civil engineering to large-scale infrastructure projects.
Wet concrete batching plant, also known as central batching plant or centralized batching plant. Its core feature is that it is equipped with a special central concrete mixer, and all raw materials, including aggregates, cement, water, additives, etc., are fully mixed in the central mixer in the batching plant. Then the finished concrete is loaded into the mixer and transported to the construction site. The mixer only plays the role of anti-segregation during transportation and no longer assumes the mixing function. The production capacity of wet batching plants is usually from 25 m³/h to 240 m³/h or higher. The hourly output of wet batching plants is usually higher than that of dry batching plants of the same specification.
Its standardized working logic is: the equipment is equipped with an independent central forced mixing host (the mainstream model is a double horizontal shaft forced mixing host). All raw materials such as sand and stone aggregates, cement powder, water, liquid addents, etc., are transported through belt conveyors and screws after completing the precise ratio in their respective independent measuring units. The machine and other exclusive conveying devices are concentrated into the central mixing host; according to the concrete markings required for construction (such as C30, C40, C50), the host completes the forced uniform mixing of materials through the set mixing speed and stirring time; after mixing, the finished concrete is directly unloaded into the transport tank. The truck was then transported to the construction site by the tank truck.
Unlike the dry concrete batching plant, the mixing process of the wet batching plant is completely completed in the station. The tank truck only assumes the function of “transporting finished materials” and does not need to be responsible for the mixing task. This technical difference directly determines the different performance of the two in terms of production efficiency, supporting conditions and quality stability of the finished products.
This section will disassemble the 11 core technical differences of the two types of equipment from the five dimensions of technical configuration, operation adaptation, engineering effect, economic cost and environmental protection compliance, and provide professional technical basis for subsequent selection.
| Contrast dimension | Dry batching plant | Wet batching plant |
| Core mixing module | No center mixing host; complete the material batching measurement, and the mixing is completed by the tank truck. | Equipped with a central forced mixing host; the whole process of ingredients and mixing is completed in the station. |
| Equipment control system | Most of them are semi-automatic/manual control, supporting customized fully automatic system; the core control of the ingredient measurement link | Equipped with a fully automatic computer control system as standard, it coordinates the whole process of measurement, mixing and conveying. |
| Structural form of equipment | Modular design, lightweight assembly; no standard styling, support high customization | It is mainly standardized and mature models, with a fixed structure and small customization space. |
| Site foundation requirements | Low load requirements, simple foundation treatment process; low input cost | The weight of the whole machine is large, and the working load of the mainframe is large; it needs to be reinforced, and the input cost is high. |
| Material control method | Water/additive is added in the tank truck; the degree of collapse can be adjusted on the spot, and the operator’s experience is highly dependent. | Water/additives are added uniformly in the station; the ratio is locked by the system, and the manual intervention space is small. |
| Supporting requirements for tankers | The tank truck needs to assume the mixing function; a sufficient number of tank trucks must be maintained, otherwise the production will be restricted. | The tank truck only undertakes the transportation function; the dependence on the number of tank trucks and mixing performance is low. |
| Continuous production efficiency | Limited by the mixing capacity of the tank truck, the continuous production capacity is limited. | Limited by the stirring capacity of the host, it can achieve large-scale and long-term continuous production. |
| Equipment procurement cost | Under the same production capacity, the procurement cost of equipment is relatively low. | Under the same production capacity, the procurement cost of equipment is relatively high. |
| Operation and maintenance costs | No stirring host consumable parts; maintenance frequency, technical difficulty and cost are all low | There are many consumable parts of the mixing host; the daily maintenance workload is large and the technical requirements are high. |
| Environmental protection emission performance | The amount of dust and wastewater generated is relatively low; it needs to be equipped with dust removal equipment, and there is no stirring wastewater. | The risk of dust, wastewater and noise pollution is high; a complete environmental protection treatment system is needed.
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| Quality stability of finished products | Affected by the mixing uniformity of the tank truck and the operator’s operation level, the risk of quality fluctuation is high. | Standardized forced mixing, the finished product is more consistent and stable. |
Under the same design capacity, the mobile dry concrete batching plant cost is much lower than that of the wet batching plant; at the same time, its lightweight equipment design reduces the construction difficulty and material cost of foundation treatment, and the foundation construction investment is only 1/3~1/2 of that of the wet batching plant.
The equipment adopts a modular design, and the size and weight of each independent module are smaller. There is no need for large transport vehicles, and ordinary flatbed vehicles can complete transportation. After arriving at the new site, assembly and debugging can be completed quickly, which has obvious adaptation advantages for mobile projects that require frequent transfers.
The structure of the equipment is simple, and there are no wearable parts such as linings, blades and bearings of the mixing host, and the daily maintenance workload is greatly reduced. Only routine inspection and cleaning of the conveyor belt, measuring sensors and dust removal devices are required. The operation and maintenance cost, technical difficulty, and professional requirements for workers are all lower.
Within the mixing capacity of the transport tanker, the on-site construction personnel can adjust the amount of water and additives added in real time according to the transportation distance, weather temperature and the actual situation of the construction site, and flexibly control the degree of concrete collapse – this characteristic is especially performed in field construction scenarios with long-distance transportation and inconvenient transportation. To stand out.
Equipment dust and wastewater are small. Combined with the sealed dust removal design of EPDAS Dry Mix Concrete Batching Plant, it can easily meet the environmental protection standards of engineering construction in most regions in China; its unorganized discharge points are concentrated in the tank truck loading link, and only need to set up simple collection and treatment equipment in the tank truck parking area. If you set it, you can achieve environmental protection and meet the standard.
The supporting cost of the tank truck is high; the tank truck needs to undertake the main mixing task, and there are strict requirements for the mixing performance and the degree of roller wear of the tank truck, and the sufficient number of supporting trucks must be ensured; if the project’s own tank truck resources are insufficient, it is necessary to rent or purchase additional tank trucks, which will greatly increase the supporting investment cost of the project.
The risk of quality fluctuation of finished concrete is high; the mixing uniformity of concrete depends entirely on the mixing ability of the tank truck and the professional experience of the on-site personnel – the deviation of any link such as the mixing speed of the tank truck, the degree of blade wear, the mixing time, the amount of water and additives, etc. will directly affect the concrete Uniformity, ease and strength stability.
It is not suitable for large-scale continuous production; limited by the mixing efficiency of the tank truck, the actual continuous production capacity of the dry batching plant is limited; if it encounters projects with large project volume and rushing construction period, the production rhythm of the dry batching plant cannot meet the needs of large-scale continuous material supply, which is easy to slow down the construction progress.
High dependence on the professionalism of construction personnel; the adjustment of the collapse degree and the control of the mixing process require on-site personnel to judge and operate according to the actual situation; if the construction team lacks rich concrete production experience and cannot accurately control the water-ash ratio and mixing time, it is easy to have the problem of unqualified concrete quality, increasing the project Quality risk.
This is the most core technical advantage of the wet batching plant. The forced mixing host equipped with the equipment can mix the materials completely uniformly within the set time; and the mixing ratio, mixing time and feeding order of concrete are all accurately locked by the fully automatic control system. The manual intervention space is small, the manual operation error is low, and the ease, strength and collapse of the same batch of concrete are maintained. The height is consistent and the quality is more stable.
Adapt to large-scale projects: The production efficiency of the wet batching plant only depends on the stirring capacity of the mixing host and has nothing to do with the tank truck; as long as the supply of raw materials is sufficient and the transportation of the tank truck is smooth, 24-hour continuous production can be realized, which fully meets the continuity of large-scale projects such as large-scale infrastructure construction and large-scale community construction. Supply demand.
The tank truck only needs to undertake the transportation task, not the mixing function. It only needs to keep the drum rotating at low speed during the transportation process to prevent the concrete from initial coagulation; the requirements for the mixing performance and wear of the tanker are relaxed, and the supporting input cost is lower.
The control system of the equipment can automatically complete the whole process of measurement, feeding, mixing and discharge. It only needs 1 to 2 operators to complete the operation control of the whole station; production data is automatically stored and abnormal situations are automatically alarmed, which greatly reduces the intensity of manual operation and labor cost.
The quality stability of the finished product of the wet batching plant makes it suitable for almost all concrete construction scenarios – from low-rise civil buildings, to high-rise and ultra-high-rise commercial buildings, to bridges, tunnels, high-speed railways and other large-scale infrastructure projects with strict concrete quality requirements, which can meet the production needs.
Equipment procurement and foundation cost are high; under the same production capacity, the equipment procurement cost of the wet batching plant is higher than that of the dry batching plant; and because the whole machine is self-large, the working vibration load is large, and the foundation treatment requirements are strict, and it is necessary to make a reinforced concrete independent foundation, the foundation construction cost, technical difficulty and construction cycle have been greatly increased.
It is difficult to transfer and disassemble; the equipment structure is complex, and each module is large in volume and heavy. Disassembly requires large-scale lifting equipment, and transportation requires multiple large vehicles or vehicles. After arriving at the new site, the technical difficulty of reinstallation and debugging is high, the cycle is long, and the transfer cost is much higher than that of the dry mixed station, which is not suitable for mobile construction projects.
The operation and maintenance workload is large and the technical requirements are high; the mixing host is the source of core consumable parts. Lining plates, blades, bearings and other parts are in contact with sand and gravel materials for a long time, which wears quickly and needs to be replaced regularly; daily operation and maintenance work also includes the inspection of the mixing host sealing system, maintenance of the lubrication system, calibration of measurement accuracy, etc. With large workload and high technical requirements, it needs to be equipped with professional operation and maintenance personnel.
Environmental protection control is difficult; the risk of dust, wastewater and noise pollution of equipment is higher, and complete dust removal, sealing, wastewater treatment, sand and gravel separation systems are required; the procurement, operation and maintenance costs of environmental protection equipment are high, and special personnel need to be arranged for daily control to ensure that the discharge meets the standard, otherwise it cannot pass the environmental protection acceptance of the project.
The project has its own tank truck resources; the engineer has a sufficient number of transport tank trucks with good mixing performance, and the drum mixing volume and stirring speed of the tank truck are accurately matched with the design production capacity of the dry batching plant – this is a prerequisite for the selection of the dry batching plant.
The construction team has rich experience in concrete control; the on-site construction personnel are familiar with the concrete ratio and mixing process, and can accurately adjust the amount of water and additives according to the transportation distance, weather temperature and construction site, and control the degree of concrete collapse and mixing uniformity.
The project site is limited, and the cost of foundation treatment is high; the construction site is small or the geological conditions are poor, and the foundation treatment cost of the wet batching plant is too high and the construction cycle is too long; the lightweight design of the dry batching plant can effectively reduce the difficulty and cost of foundation treatment.
There is no demand for large-scale continuous production and supply; the single concrete supply of the project is small, the supply rhythm is relaxed, and there is no need for long-term continuous production; for example, for small civil construction, road maintenance, small bridge foundation and other projects, the production capacity of dry batching plants is enough to cover the demand.
The project budget is limited, and the early equipment investment is strictly controlled; the project construction funds are tight, and it is necessary to reduce the early investment cost of equipment procurement and foundation treatment; the equipment body and foundation investment cost of the dry mixed station is lower, which can effectively alleviate the capital pressure.
The quality requirements of finished concrete are strict; the project has high requirements for the strength, ease and collapse consistency of concrete, such as high-rise/ultra-high-rise civil buildings, large bridges and tunnels, high-speed rail hubs, large factories and other key projects, and the standardized forced mixing of wet batching plants can stably ensure the quality of the finished product.
It requires large-scale and long-term continuous production and supply; the single supply of the project is large, and requires continuous feeding for a long time, such as large-scale foundation raft pouring, large-scale bridge pier pouring and other construction scenarios. The continuous production capacity of the wet batching plant can fully meet the needs of construction progress.
The resources of the own tank truck are insufficient, or the performance of the tank truck is average; the number of tank trucks owned by the engineering party is small, or the service life of the tank truck is long, the mixing blades are seriously worn, and the mixing performance cannot meet the production requirements of the dry batching plant; the wet batching plant has a low dependence on tank truck, which is more suitable for such scenarios.
The professional ability of the construction team is average and lacks quality control experience; the on-site construction personnel lack professional experience in concrete ratio and mixing technology, and cannot accurately control the collapse adjustment and mixing process control of the dry batching plant; the wet batching plant has a high degree of automation and small artificial intervention space, which can reduce manual operation error.
The project has rigid requirements for environmental protection compliance; the project location has strict environmental protection control, and the requirements for dust and wastewater discharge are extremely high; the wet batching plant can stably meet environmental protection standards by configuring a complete sealing, dust removal and wastewater treatment environmental protection system, while the tanker of the dry batching plant has no organized emission risk, and it is more difficult to meet the strict environmental protection requirements.
Q1: Can the dry concrete batching plant produce high-quality concrete?
Answer: Yes, but the quality stability is not as good as that of the wet batching plant. The quality of concrete produced by dry batching plant depends on many factors such as truck mixing efficiency, mixing time, drum condition, etc. There may be certain differences between batches. The wet batching plant completes the mixing under controlled conditions, and the quality consistency is higher. For high-standard projects (such as high-rise buildings, bridges, dams, etc.), wet batching plants are a more reliable choice.
Q2: Is the wet batching plant better than the dry batching plant?
Answer: Not necessarily. There is no absolute “best”, only “most suitable”. Wet batching plants have advantages in terms of concrete quality and consistency, but the initial investment is higher and the transportation radius is limited. Dry batching plants have advantages in terms of cost, transportation distance and on-site flexibility. Which type to choose should be based on factors such as project scale, transportation distance, quality requirements and budget.
Q3: What are the special requirements of the dry batching plant for the mixer truck?
Answer: Dry batching plants have higher requirements for transport tank trucks. The tank truck needs to complete the mixing task during transportation, so it has higher requirements for the mixing function, blade condition and mixing efficiency of the drum. The tank truck needs to control the rotation of the tank at a speed of at least 70 rpm. At the same time, the rollers and stirring blades of the tank truck are also more worn, and the maintenance cost is relatively high.
Q4: Is the mobile batching plant dry or wet?
Answer: Mobility and mixing method are two independent dimensions. Dry and wet batching plants can be designed as fixed or mobile. Mobile dry batching plants and mobile wet batching plants both exist in the market and are suitable for different project scenarios respectively.
Q5: How long is the storage time of the dry batching plant?
Answer: The dry mixture produced by the dry batching plant will not be hydrated because no water is added, so the storage time is long, usually up to 3 to 6 months. The wet concrete produced by the wet batching plant must be used before condensation, and the storage time is very short, generally no more than 24 hours.
Q6: What is the difference between the sand treatment of the two batching plants?
Answer: The sand used in the wet batching plant does not need to be dried. The sand used in the dry batching plant needs to be dried to ensure better grading and construction quality. The drying treatment of sand will increase the raw material preparation cost of the dry batching plant.
Q7: What is the degree of automation of the dry batching plant?
Answer: The control system of the dry batching plant is more inclined to manual control (various switches and buttons on the control panel) or semi-automatic control (control cabinet + semi-automatic digital display control instrument). The wet batching plant is more inclined to fully automatic control (computer + software + control module). However, modern dry batching plants have also begun to adopt more and more PLC-based computer-aided control technology.
Q8: What is the material loss of the dry batching plant during transportation?
Answer: The loss of dry material in the dry batching plant is relatively low during transportation, which can usually be controlled within 2%; while the loss of wet concrete in the wet batching plant during transportation is usually 5%-8%. This is also an advantage of the dry batching plant.
Dry batching plant and wet batching plant are two types of concrete production equipment adapted to completely different engineering scenarios. There are essential differences between the two in terms of technical principle, operation logic and adaptation conditions. There is no absolutely perfect equipment, only the selection plan that meets the actual needs of the project.
In the process of selection, the engineer should not only look at the paper parameters of the equipment, but also combine the site conditions, supporting resources, construction requirements and comprehensive costs of the project to carry out all-round evaluation and comparison. If necessary, you can contact the professional concrete batching plant supplier to provide the detailed working conditions of the project and obtain an accurate customized equipment configuration plan.
