Screen tower quality appraisal

sieve plate tower is based on the core principle of gas-liquid mass transfer and fluid mechanics synergy. By optimizing the opening ratio, tray spacing and liquid flow distribution uniformity, it achieves the synergy of separation efficiency, operating flexibility and anti-clogging properties. It is widely used in petroleum distillation, chemical separation, gas purification and solvent recovery and other fields. In oil refining, it is used for component cutting of crude oil atmospheric and vacuum distillation; in chemical production, it meets the needs of precise fractionation of azeotrope systems; in the field of environmental protection, it ensures the mass transfer efficiency of VOCs waste gas absorption. Compared with the packed tower, the sieve plate tower has the characteristics of simple structure, low pressure drop and low maintenance cost, and is the core equipment of the continuous separation process.

Zhongke Testing is a product quality appraisal service organization registered with the court. It can provide sieve plate tower quality appraisal services. It has a professional appraisal team and advanced instruments and equipment to provide fair and accurate appraisal results for sieve plate tower quality appraisal.

As the separation process becomes more precise, related quality dispute cases have increased significantly. The judicial dispute focuses on:

1, performance index dispute: separation efficiency is not up to standard, insufficient operating flexibility;

2, material defects: insufficient Cr content in stainless steel tray plate, deep orifice erosion

3, process problems: tray level deviation, downcomer design defects;

4, contract performance dispute: key parameters (such as opening ratio, overflow weir height) are inconsistent with the technical agreement.

Technical methods for quality identification of sieve plate towers mainly include:

1. Visual inspection: Check whether the sieve plate has defects such as damage, corrosion, deformation, etc., and whether the tower body has cracks, leaks, etc.

2. Dimensional measurement: Measure the sieve plate aperture, spacing, height and other dimensions to see if they meet the design requirements.

3. Material testing: Conduct composition analysis, mechanical property testing, corrosion testing, etc. on the sieve plate and tower body materials to determine whether the materials meet the standard requirements.

4. Process test: simulate actual working conditions, conduct mass transfer efficiency, pressure drop and other performance tests on the sieve plate tower to verify whether the equipment meets the design specifications.

A petrochemical plant of the applicant signed a "Crude Oil Fractionation Sieve Plate Tower Purchase Contract" with an equipment manufacturer of the respondent, and it was agreed that the theoretical number of plates should be ≥ 12 pieces/m. After the production was put into operation, the yield of light components was insufficient, and the manufacturer argued that it was caused by changes in the feed composition.

identification analysis results:

The quality analysis expert group discussed and comprehensively analyzed the relevant information of the "sieve plate tower", contract technical agreement, on-site investigation case materials and other data, and made the following quality analysis opinions :

The tray opening rate of the sieve plate tower involved in the case is only 7.2% (agreement 10±0.5%), and the cross-sectional area of the downcomer has shrunk by 15%; the tray level deviation is 3mm/m, resulting in uneven distribution of the liquid phase; the Ni content of 304 stainless steel is 7.2% (agreement ≥8%), and the orifice erosion rate exceeds the standard.

The appraisal conclusion concluded that design and material defects were the main causes of insufficient efficiency.

Sieve plate tower crane quality appraisal report should include:

1, appraisal purpose (such as separation failure attribution, safety compliance verification) and reference standards;

2, involved equipment model, design drawings, operating data;

3, testing method and equipment list (such as Laser rangefinder, industrial chromatograph);

4, analysis of the correlation between test data and failure (such as the impact of hole opening ratio on the number of theoretical plates);