Quality appraisal of lime shaft kiln

vertical kiln is a vertical cylindrical intermittent production equipment, consisting of a kiln body, a combustion chamber, a feeding device, a discharging device, etc. The kiln body is equipped with a refractory lining and a multi-layer grate. Materials are added from the top of the kiln, fall layer by layer under the action of gravity, and are discharged from the bottom of the kiln after preheating, calcination, cooling and other stages.
In the case of lime shaft kiln quality appraisal, Zhongke Testing can provide lime shaft kiln quality appraisal services.

1) can be divided into:
clay shaft kiln (calcining temperature 1300-1400℃), (calcining temperature 1600-16 50℃), (calcining temperature 12000-1300℃), (calcining temperature 1600-1650℃), (calcining temperature 14500-1650℃);
2) press The fuel types used can be divided into:
solid fuel vertical kiln (coke, anthracite as fuel); liquid fuel vertical kiln (using heavy oil as fuel); gas fuel vertical kiln (coke oven gas fuel, mixed gas, natural gas);
3) according to different air supply methods can be divided into:
forced ventilation vertical kiln uses a blower to blow air into the kiln to strengthen the forging process.
natural ventilation shaft kiln: The gas flow in the kiln mainly relies on the natural suction force of the shaft itself.
4) According to the degree of mechanization, it can be divided into: manual feeding vertical kiln, mechanized vertical kiln, and complete mechanization from feeding to discharging.

GB/T 32994-2016 Rotary kiln for cement industry
GB/T 41333-2022 Technical requirements for lime calcination complete equipment
GB/T 9934-1988 Measurement and calculation method of thermal balance of lime mechanized vertical kiln
JC/T 2582-2021 Lime mechanized shaft kiln automation control device
YB/T 4693-2018 Unfired lining bricks for active lime rotary kiln

In order to reduce resource consumption, a company invested in the construction of a lime shaft kiln project with a daily output of 300 tons. After the company reported that the project could not operate normally, a dispute arose between the designer, a technology company, and the construction company, over liability. After the case was brought to the local court, the court commissioned a technical appraisal of the lime shaft kiln project.
identification and analysis results:
The expert group conducted discussions and comprehensive technical analysis based on the relevant information of the "lime shaft kiln" provided by the client, the on-site investigation and inspection results, and the sampling inspection results, and made the following quality analysis opinions:
1. The technology company submitted a total of 3 drawings to the construction company. After review and analysis by the appraiser, it was found that the layout of the burners in the "Stereoscopic Layout Drawing", "Masonry Master Drawing" and "Combustion System Configuration Master Drawing" were completely inconsistent, and the elevation data of the top of the furnace body was inconsistent with the elevation data of the upper and lower rows of burners. In summary, there were inconsistencies in the three drawings of the project.
2. In the project design, there is no independent fire control device for a single burner, no independent flame observation hole and temperature monitoring device, and there is no independent climbing device for the kiln body barrel, making it impossible to quickly adjust the temperature condition of a single burner. During the calcining process of the lime shaft kiln, the calcined material will block or block the burner, which will eventually lead to insufficient temperature in some areas, resulting in raw burning.
3. The ladder outside the entire furnace body adopts Z-shaped assembly and welding. The actual platform ladder provided in the "General Drawing of Platform Ladder" is annular winding upward assembly and welding. This shows that the ladder outside the furnace body is inconsistent with the design drawing. During the on-site construction process, the welding platform ladder was not assembled according to the drawing.
4. The composition of the raw stone samples was analyzed. The composition of the limestone was 52.7%, which is about 53%, which basically complies with the relevant requirements in the "Contract Supplementary Agreement".
In summary, this lime shaft kiln project has quality problems in design and construction.