Selection of treatment technology for asphalt smoke produced by asphalt mixing plants

When an ordinary asphalt mixing station completes the mixing operation, it will cause great pollution to the surrounding environment. In order to solve this problem, environmentally friendly asphalt mixing equipment came into being. What are the characteristics of this type of equipment?

The asphalt mixing plant contains multiple different systems with different functions. The drying system is one of them. Its main function is to heat and dry the materials to reach the temperature required for the process. In order to successfully achieve this goal, the drying system must provide a certain amount of heat.

Asphalt mixing plant is also called asphalt mixture mixing equipment, which is mainly used to produce asphalt mixtures of various specifications. It is an important equipment in projects such as road construction, highway maintenance and airport runway construction. The main components of an asphalt mixing plant include cold material supply system, drying drum, screening system, weighing system, agitator, finished product silo and control system.
The workflow of an asphalt mixing plant is generally as follows:

The quality of asphalt mixture directly determines the quality of asphalt pavement engineering. This article discusses the key points of supervision of ordinary highway asphalt plants in order to better monitor the quality of asphalt mixture.

As an important production equipment in construction, asphalt mixing plant has high production investment. Therefore, production is very important during use, but daily maintenance is also very important. In addition to regular maintenance, routine maintenance is also essential. The editor of Asphalt Mixing Plant shares some key points of daily maintenance and scheduled maintenance;

If you look at an asphalt mixing plant from a professional perspective, do you know how to judge its work and significance? In fact, the so-called asphalt mixing station is the one that produces asphalt. We can usually see it in road construction projects. Specifically, it mixes some materials that need to be used during the construction process according to certain proportion requirements. Then complete the corresponding construction work.
Then, we can analyze it from a market perspective. Since it was used in the market, it has been widely praised by users. Today’s asphalt mixing plant technology has been greatly improved, and the entire set of equipment used has a variety of advantages. , such as meeting the requirements of stable control, screening, efficient dust removal, excellent mixing, and green environmental protection during the work process. It is even more obvious when used in large-scale projects such as high-grade highways and airports.

1. Causes of overflow
The main causes of spillage are:
1) Mixing materials in cold silo. Cold material warehouses generally have 5 or 4 warehouses. Each warehouse is required to contain pellets of a certain specification. If cold materials of different specifications are mixed or mistakenly loaded during the loading process, it will cause certain occurrences in a certain period of time. The shortage of pellets of one specification and the overflow of pellets of another specification can easily destroy the supply balance between hot and cold silos.

There is also a reversing valve in the asphalt mixer, which generally does not cause problems, so I have not understood its solution in detail before. But in actual use, we encountered this kind of failure. How should we deal with it?

With the changes in society and the transformation of the economy, real estate and construction are developing rapidly. When building and constructing houses, most of them use some equipment, such as mixing plants. The asphalt mixing plants produced by our company have a high level of mechanization and high production efficiency.
What is an asphalt mixing plant? It is a combined device used for centralized mixing of concrete, also known as a concrete prefabrication site.
With the development of municipal construction, the use of centralized mixing and the provision of commercial mixing plants have great advantages, so it has developed rapidly and created conditions for promoting concrete pumping construction and realizing the joint operation of mixing, conveying and pouring machinery. It is mainly composed of five major systems, including a mixing host, a material weighing system, a material conveying system, a material storage system and a control system, as well as other ancillary facilities. However, there are some faults in normal times. What are the specific ones in the gas source failure?

The core of the asphalt mixing plant is its electronic control system. If it has problems, it will cause a lot of trouble to use. However, in actual use, the electronic control system in the asphalt mixing plant will inevitably encounter some problems and failures. How to solve it at this time?
If only the instrument display of the electronic control system of the asphalt mixing plant is inaccurate, it means that the weighing system may be affected by external forces; or the drift error of the sensor causes the weighing zero position or weighing interval to change; it may also be caused by sensor damage.

Asphalt mixing plant, also known as asphalt concrete mixing plant, asphalt mixing equipment. Refers to a complete set of equipment used for mass production of asphalt concrete. According to the mixing method, it can be divided into intermittent type and continuous type; according to the transportation method, it can be divided into fixed type, semi-fixed type and mobile type.

Main uses of asphalt mixing plant
Asphalt mixing plant, also called asphalt concrete mixing plant, can produce asphalt mixture, modified asphalt mixture, and colorful asphalt mixture, fully meeting the needs of constructing expressways, graded highways, municipal roads, airports, ports, etc.
The overall composition of asphalt mixing plant
Asphalt mixing equipment mainly consists of batching system, drying system, incineration system, hot material improvement, vibrating screen, hot material storage bin, weighing mixing system, asphalt supply system, powder supply system, dust removal system, product silo and control system, etc. Some composition.

In fact, asphalt mixing stations are not uncommon in our daily lives. They are mainly a unit of equipment specially designed to mix asphalt. What we really don’t understand is the gas system of the asphalt mixing station. Only correct maintenance And operation can bring out the best production effect. So what are the faults in the gas circuit of asphalt mixing station?
The following three points are the more common gas path failures of asphalt mixing stations:

Certain failures cannot be avoided during the use of the asphalt mixing plant. For example, a malfunction of the cold material feeding device may cause the asphalt mixing plant to shut down. This may be due to a malfunction in the asphalt mixing plant or due to gravel or foreign matter being trapped under the cold material belt.

Asphalt mixing plant is one of the main equipment for producing asphalt concrete. It can mix asphalt, gravel, cement and other materials together in a certain proportion to obtain the products required for highway construction. In order to ensure its operating effect, the asphalt mixing plant also needs to be powered on for trial operation before it is officially put into work.
The first step in commissioning is to run a single motor and check whether the current, steering, insulation and mechanical transmission parts are operating normally. After confirming that each motor and mechanical transmission parts are operating correctly, conduct a joint trial run. During the entire process, it is necessary to conduct patrol inspections of key parts. If any abnormal noise is found, the cause should be identified and eliminated in a timely manner.

The development prospects of asphalt mixing plants are very good, and the product competition on the market is also very fierce. When the equipment is used, uneven wear of the supporting wheels and wheel rails often occurs, and sometimes there are some abnormal noises and edge gnawing. The main reason is that after the asphalt mixing station has been working for a period of time, the drying cylinder is exposed to high temperature and friction occurs between the supporting wheel and the wheel rail.
Under the action of drying materials in an asphalt mixing station, the equipment will vibrate violently, which will directly lead to improper adjustment of the gap between the wheel rail and the supporting wheel, or mutual interference between the two. The position is skewed, so the operator needs to add grease to the surface contact positions of the supporting wheel and the calibrating wheel rail after every day’s work.

Asphalt mixing plant is one of the main equipment for producing asphalt concrete. It can mix asphalt, gravel, cement and other materials together in a certain proportion to obtain the products required for highway construction. In order to ensure its operating effect, the asphalt mixing station also needs to be powered on for trial operation before it is officially put into work.
At the beginning of the test run, first run a single motor, and at the same time check whether the current, steering, insulation and mechanical transmission parts are operating normally. After confirming that each motor and mechanical transmission parts are operating correctly, conduct a joint trial run. During the entire process, it is necessary to conduct patrol inspections of key parts. If any abnormal noise is found, the cause should be identified and eliminated in a timely manner.

Colored asphalt pavement is a kind of special pavement material that mixes colored particles into asphalt and then lays on the pavement

Asphalt mixing stations, also known as asphalt concrete mixing stations, can produce asphalt mixtures, modified asphalt mixtures, and colored asphalt mixtures, which fully meet the needs of building highways, grade roads, municipal roads, airports, ports, etc. Changmeng Electric Power introduces the safety operating procedures of asphalt mixing plants below:
1. During the operation of the mixing equipment, in addition to ensuring that the equipment is in good condition, it should also be equipped with a mineral moisture content detector and a finished material tester, and the relevant data should be frequently tested for the operator to adjust the operation in time to keep the equipment in good condition.
2. In addition to affecting production capacity, the moisture content of mineral materials is also the main factor determining fuel consumption. Additional material sheds should be added.
3. Before operation, all working parts and devices of the mixing equipment should be fully checked to see if they are intact and normal. If there are any problems, they must be properly handled before operation, and it is forbidden to operate with illness.
4. The operation must be carried out strictly in accordance with the procedures and precautions specified in the instruction manual. After normal ignition, the dust collector should be monitored to ensure that the drying drum burns under negative pressure; after production starts, the hot material elevator and agitator should be monitored to see if they are working normally to coordinate the operation of other parts.

When we operate the asphalt mixing station, we should heat the equipment half an hour in advance, and the clear tank should be heated for at least two hours; and manually operate each part of the equipment to ensure that it is in good operation. status; it is also necessary to conduct relevant inspections on the valves and manually collect and return oil to ensure that the equipment can operate normally.
Several requirements for safe operation of asphalt mixing plants:

Construction safety has always been a major issue, and we cannot let any safety hazard go unnoticed. Especially the use of equipment at the construction site. Asphalt mixing stations are prone to failure. Strengthening the maintenance of this equipment is essential to ensure safe construction at the construction site, improve equipment integrity, reduce equipment failures, and ensure the quality of concrete. The role of neglect.
The composition of the asphalt mixing plant is relatively complex, so during maintenance, classified maintenance should be carried out according to the usage and functions of different parts. Maintenance content can be divided into tank maintenance, winch system maintenance and adjustment, stroke limiter adjustment and maintenance, wire rope and pulley maintenance, lifting hopper maintenance, track and track bracket maintenance, etc.

Asphalt flue gas treatment methods, their principles and characteristics, and an asphalt flue gas environmental protection treatment plan based on the actual asphalt flue gas problems faced by the unit.

1. Basic situation
My unit’s mixing plant is equipped with a 4000-type asphalt mixing plant. During daily production of the asphalt mixing plant, a large amount of asphalt smoke will be emitted from the mixing pot discharge port. This smoke not only has an unpleasant smell, but also contains A large number of compounds that are harmful to the human body, such as benzopyrene, benzanthracene, carbazole and other polycyclic aromatic hydrocarbons, mostly have carcinogenic risks. Smoke overflow will cause pollution to the surrounding atmospheric environment and affect the personal health of workers. Although the overflow port of the mixing station is equipped with a dust retaining wall, the fine dust is seriously raised, and the cold material belt conveyor is dusty. In order to protect the environment, reduce pollution, and reduce cost investment, based on full research and absorption of technology in the same industry, and combined with the actual situation of asphalt mixing, we are planning to install asphalt mixing bag dust collectors to the flue at the discharge port of the mixing pot to control asphalt fumes. Gas is processed. The dust removal efficiency of the bag dust collector can reach 97%~99%, and the dust-containing gas can be purified to a level of 50mg/Nm3.

There is also a reversing valve in the asphalt mixing plant, which generally does not cause problems, so I have not understood its solutions in detail before. But in actual use, we encountered this kind of failure. How should we deal with it?
The failure of the reversing valve of the asphalt mixing station is not complicated, that is, the reversing is not timely, gas leakage, electromagnetic pilot valve failure, etc. The corresponding causes and solutions are of course different. For the reversing valve to not change direction in time, it is generally caused by poor lubrication, the spring is stuck or damaged, oil dirt or impurities get stuck in the sliding part, etc. For this, it is necessary to check the status of the lubricator and the quality of the lubricating oil. Viscosity, if necessary, the lubricant or other parts can be replaced.
After long-term use, the reversing valve is prone to wear of the valve core sealing ring, damage to the valve stem and valve seat, resulting in gas leakage in the valve. At this time, the sealing ring, valve stem and valve seat should be replaced, or the reversing valve should be replaced directly. In order to reduce the failure rate of asphalt mixers, maintenance must be strengthened on a daily basis.

Natural gas is a colorless, odorless, flammable and explosive gas, the main component of which is methane, which accounts for about 98% of natural gas. The density of natural gas is lower than that of air and it is difficult to liquefy. Natural gas is not only a clean green energy for civil, commercial and industrial use, but also a raw gas for chemical industry. The theoretical ignition value of natural gas is 540 degrees, the combustion temperature is 1970 degrees, the calorific value is 40MJ/m3, and the explosion limit is 5%-15%. CNG refers to natural gas that has been compressed to 20-25MP and stored in high-pressure gas tank trucks, and then transported to various gas transmission points to supply gas to residential users, commercial users and industrial users. In order to ensure the normal operation and safety of the asphalt mixing station and our pressure regulating station, our company has specially formulated the following safety protection measures.

Many people think that since both asphalt mixing plants and asphalt mixing plants are equipment for producing asphalt, there should be no difference between them, even if there is, it is only in appearance and volume. However, asphalt mixing plants and asphalt mixing plants are different in even their basic structure and function.
First, let me introduce the basic structure of an asphalt mixing plant, which includes five major components: material supply system, metering system, mixing system, and electrical control system. In comparison, the structure of an asphalt mixing plant is simpler, without so many components, so its operation and maintenance will be simpler.

Asphalt mixing stations and equipment must implement secondary leakage protection measures. They can only be used after being plugged in and operated through the circuit breaker before use. During the trial operation, it is necessary to verify that the rotational speed of the mixing drum will be inappropriate.

In today’s road construction, the use of a large number of road construction machinery represents the entry into the era of highway mechanization. For users, the goal is to use road construction machinery reasonably and tap its potential as much as possible. However, road construction machinery requires various accessories to work together. Now let’s take the asphalt mixing plant as an example to see what commonly used accessories and equipment are available.
Asphalt mixing plant equipment is a relatively complex system, which includes many equipment, mainly nine parts, namely: bag dust removal, finished material temporary storage warehouse, grading machine, fast heating asphalt tank, asphalt barrel removal machine, asphalt recycled material crushing and screening system, coal block crusher, coal mill and dust removal equipment, etc.

At present, the assembly and installation technology of large-scale asphalt concrete mixing equipment in high-grade highway construction is gradually improving. In order to improve work efficiency, it is necessary to analyze the pretreatment agent for the selection and matching of large-scale mixing equipment and auxiliary equipment, and clarify the installation and commissioning of asphalt stations. With the continuous change of highway construction methods, it is necessary to adopt production equipment according to the requirements of the development of the times. Intermittent asphalt mixing equipment is a widely used road construction equipment with the characteristics of simple operation and high work efficiency. Relevant staff are required to master the installation, construction and management methods of mixing equipment.