Light weight aggregate (LECA) industry
Polluted soil ceramsite production line
Production Line Introduction
Contaminated soil is a waste product produced by modern industrial production. Due to unorganized discharge or failure of the discharge system, it seeps into the soil layer, causing changes in the physical, mechanical and chemical properties of the soil, directly affecting engineering activities or being harmful to human health, animal reproduction, plant growth, etc. With the implementation of my country's environmental protection policies, how to achieve harmless, resource-based and stable disposal of contaminated soil as solid waste is what everyone has been exploring.
Through the analysis of contaminated soil and continuous small and medium-scale tests, our experimental center has explored a way to use rotary kilns to burn expanded clay, truly achieving the harmless, resource-based and stable disposal of contaminated soil.
Outstanding advantages
The main goal is to achieve the reduction, harmlessness and resource utilization of polluted soil, sludge or solid waste disposal
● Our company combines hazardous waste technology with the tail smoke chamber of ceramsite production kiln, and uses the waste heat for heat exchange, and then uses it for drying general solid waste, reducing energy waste and exploring an energy-saving way for flue gas treatment.
● Provide complete whole industry chain services from overall project planning to detailed process formula, process design, equipment design and manufacturing, engineering installation, commissioning, etc., and have complete solid and hazardous waste treatment system solution capabilities
● The company's pilot test line can conduct raw material composition analysis, formula design, sample preparation, roasting, small-scale and pilot tests of various ceramsite
Process
After the initial stone removal, coarse crushing, fine crushing, batching, mixing, aging, granulation, calcination and cooling, the contaminated soil is formed into building ceramsite. By staying in the rotary kiln for more than 30 minutes at high temperature and calcining at about 1100℃, some heavy metals in the contaminated soil are wrapped and oxidized and reduced to form stable chemical elements, thereby achieving the purpose of solidification. The produced ceramsite can be used in building blocks, wall panels, bathroom backfill, garage roof backfill, roof leveling, square bricks, flower cultivation, etc., which can achieve the purpose of resource utilization and stabilization at the same time, pointing out a sustainable development path for the disposal of contaminated soil.
The contaminated soil is stored in the shed for about 30 days. The clay particles of 10-30mm are sent to the silo by a forklift, and then sent to the double-shaft mixer by a box feeder via a belt conveyor for forced mixing and stirring to reduce the particle size and make the composition uniform, and then enter the roller granulator for extrusion granulation. The granular balls from the granulator are sent to the dryer by a belt conveyor, and after drying, they are sent to the ceramsite rotary kiln for preheating and roasting. The fired ceramsite products fall into the cooler for cooling, and then are screened by the rotary screen into finished products of different particle sizes, which are stored in the yard and shipped after bagging. The natural air that cools the ceramsite in the cooler is heated to form high-temperature secondary air, which enters the rotary kiln for auxiliary combustion, which can save fuel. The fuel is sent to the rotary kiln for combustion by a high-pressure fan through a multi-channel burner. The dusty high-temperature flue gas at the end of the kiln enters the air cooler for cooling, and then enters the bag dust collector for purification and emptying.
Production process introduction
1. Raw material process
The main raw material is clay or mud. Build clay (or mud) storage silos and fly ash storage silos, use loaders to take materials, and make appropriate mix ratios. When the clay particle size is too large, a roller crusher should be used to crush it to obtain a smaller particle size.
2. Mixing and granulation
A plate feeder is set under the hopper. The material is fed into the double-shaft mixer. Then the material falls into the double-roll granulator and becomes a spherical material of 5-10mm. Then it is fed into the inserted rotary kiln through a belt conveyor.
3. Preheating and combustion.
When the formed balls enter the preheating kiln through the chute, the moisture is dried and sent to the firing kiln to produce lightweight expanded clay aggregate (LECA) with a bulk density of 500kg/m3.
4. Cooling
The Lightweight Expanded Light weight aggregate (LECA) (LECA) outlet from the kiln will be fed into the cooler. The cooler adopts a single drum cooler.
5. Fuel Combustion
Coal, natural gas and biomass fuels are good choices.
6. Dust removal at kiln mouth
The air from the kiln is treated by the air cooler and then sent to the bag filter for dust removal. Then it will be sent to the sky.
7. Final product screening and packaging.
Light Expanded Light weight aggregate (LECA) (LECA) is exported from the rotary cooler and then sent to the vibrating screen (or rotary screen). The screening size is 5mm, 15mm and 25mm. Different sizes will be packed in different bags for sale.
Production line characteristics
1. Energy saving and environmental protection
The production process is advanced, the single production line has large production capacity and low heat loss. The LECA device uses advanced bag dust collectors to keep the flue gas concentration below 20mg/Nm3.
2. High degree of automation
The Leca production line is equipped with temperature and pressure monitoring instruments, the operating parameters are displayed by computers, and advanced computer control can be used to achieve automatic operation of the entire system.
3. Investment losses
According to the characteristics of lightweight expanded clay aggregate, a double-drum inserted rotary kiln is used to control the preheating and calcining process. The LECA production line adopts energy-saving preheater with advanced technology, reasonable design and high technical level.
parameter
| No | Indicator | unit | value | ||||
| 1 | capacity | m3/a | 15000 | 25000 | 35000 | 50000 | 100000 |
| 2 | product | ||||||
| ① | Light expanded clay aggregate | m3/a | 15000 | 25000 | 35000 | 50000 | 100000 |
| 3 | Main fuel and raw material consumption | ||||||
| ① | Contaminated soil | t/a | 8800 | 14700 | 20500 | 29400 | 58800 |
| ② | shale | t/a | 8300 | 13900 | 19400 | 27800 | 55600 |
| ③ | coal | t/a | 1360 | 2270 | 3180 | 4540 | 9080 |
| 4 | power consumption | ||||||
| ① | freshwater | t/a | 1000 | 1500 | 2500 | 3000 | 6000 |
| ② | energy | kWh/a | 187500 | 312500 | 875000 | 1250000 | 2500000 |
| 5 | Number of employees required | a | 15 | 17 | 18 | 20 | 22 |