Key points for the construction of vertical environmental protection lime kiln
As the core equipment of modern lime industry, the construction quality of vertical environmentally friendly lime kilns directly affects production efficiency, energy consumption control, and environmental compliance level. Based on industry practice and technical specifications, the construction process should focus on the following key links:
1、 Basic construction: bearing capacity and stability guarantee
The foundation is poured with C30 heat-resistant concrete, compacted and compacted in layers, and settlement observation points are reserved. The pre embedded error of anchor bolts should be controlled within ± 2mm. Oil stains should be removed before secondary grouting, and non shrink grout should be used for filling. The basic maintenance period shall not be less than 28 days, during which temperature changes shall be monitored to prevent concrete cracking.
2、 Kiln body masonry: refractory materials and process control
Refractory bricks need to remove bricks with cracks or size deviations exceeding 1mm, and construction should be carried out using the ring masonry method. The joints of each layer of bricks should be staggered by ≥ 30 °, and the thickness of the joints should be 1.5-2mm. Wedge shaped bricks should be used in conjunction with straight bricks at the arch top, and the insertion depth of the locking bricks should be at least 2/3 of the brick length. Reserve 10-15mm expansion joint at the junction of the kiln body, fill it with ceramic fiber blanket and apply refractory slurry for sealing. The heating rate during kiln drying should be strictly controlled at 20-30 ℃/h to avoid cracking of refractory materials.
3、 Equipment Installation: Accuracy and Sealing Requirements
When assembling the large gear with the cylinder, the overall clearance error of the interface is ≤ 0.5mm, and the meshing contact spot is ≥ 40% along the tooth height and ≥ 60% along the tooth length. The installation of the supporting wheel group must ensure that the parallelism error with the kiln axis is less than 0.05mm/m, and laser theodolite calibration is used. Hydraulic gear wheel system no-load test run, check whether the cylinder stroke and pressure parameters match the design values.
4、 Environmental protection system integration: ultra-low emission standards
The weld seam of the dust collector shell is subjected to kerosene penetration test, and the flatness deviation of the flower plate is ≤ 3mm. The filter bag is left to stand for 48 hours before installation, and the compression of the bag seal strip is 30% -40%. When testing the coverage of nozzles in the spray layer of the desulfurization tower, the difference in spray volume in any 1 ㎡ area should be ≤ 15%. The sampling probe of the online monitoring system should avoid the eddy current zone and be at least 1/4 of the flue diameter away from the flue wall.
5、 Construction management: full process quality control
Establish a three-level inspection system: self inspection by teams, re inspection by quality inspectors, and on-site acceptance by supervisors. The quality of refractory material masonry is checked by using an endoscope to measure the compactness of brick joints, and the accuracy of gear meshing is checked for contact spots using a coloring method. The system is debugged continuously for 72 hours to record parameters such as the axial displacement of the kiln body and the temperature of the supporting wheel tile, ensuring that the lime activity is ≥ 280mL, the unit product heat consumption is ≤ 4.2GJ/t, the dust emission concentration is ＜ 10mg/m ³, and the nitrogen oxide emission concentration is ≤ 100mg/m ³.
By strictly controlling the above construction points, efficient construction of vertical environmentally friendly lime kilns can be achieved, providing stable, low consumption, and environmentally friendly operational guarantees for subsequent production.
