Applications of KHD Company’s Large-scale Production Improvement Technologies on Pyro-processing Systems with Chinese Design

London, 30th July 2020 - Guest blog by Yuanli Man & Xudong Bian

AVIC International Beijing Co., Ltd (AVIC) - KHD Humboldt Wedag

 

The main contents and effects of KHD Humboldt Wedag’s technical upgrade proposal are introduced, using a case study from the upgrading of 11 cement production lines in a large cement group in China.

(This blog is an excerpt from the full article, which can be viewed here, complete with figures and graphics - WCA Member login required)

Introduction

In recent years, it has become more and more difficult to add new cement production lines in China. Hence, it is the first choice for many cement enterprises to optimise and upgrade existing lines to increase production, save energy, and reduce emission. As a famous enterprise in the world cement industry, Humboldt company (hereafter referred to as KHD) has some unique technologies, such as high-efficiency low-pressure loss preheaters, two-pier kilns, burner, roller press and high-efficiency denitrification, etc. Since the beginning of 2019, KHD has used its proprietary technology to upgrade the kiln systems of 11 cement production lines in China, the main content of which is to increase the production of 5000TPD kiln to 7000 TPD or above. The following article focuses on the technical aspects and impacts of the implementation of the upgrading projects.

Determining the Target of Production Increase

To determine the production target is the core requirement of the upgrade. KHD and the factory’s engineers can finally determine the production line through site investigation, data collection, operation observation, preliminary audit, preliminary discussion and final audit of each production line.

Cement Plant Technical Audit

The audit is carried out in the following steps:

  • Make questionnaires and technical information list: The list shall be sent to the cement plant one to two weeks in advance.
  •  Site investigation: The on-site investigation generally takes 5-6 days.
  • Provide audit report: After the on-site investigation, KHD generally provide a formal audit report within one month and confirms the upgrade guarantee values.
  • Confirm technical service agreement: The agreement includes upgrade scope, technical index, performance guarantee, design scope, supply scope and schedule of both parties.

Engineering - Outlining KHD’s engineering scope generally;

  • Preheater, calciner, kiln inlet chamber, kiln head hood, burner, etc., including equipment arrangement drawing, load data, 3D schematic diagram, technical specifications, etc;
  • Provide the technical parameters required for other equipment to be modified (such as kiln drive, ID fan, exhaust gas fan, cooler, filter, coal powder supply, feeding raw meal, etc;
  • Non-standard equipment drawing, site fabrication drawing and refractory drawing;
  • PID diagram, list of consumption points, list of instruments and meters of pyro-processing system

Equipment Supply Scope of KHD: The scope of supply of KHD project is generally: burner (option item), C2-C5 dip tube, expansion joint, flap valve, sprinkle plate (box), access door, poke hole, etc., and the rest are fabricated and purchased by the cement plant on site.

Raw Meal/Fuel Requirement: Because the upgrading is going on under the existing conditions, it is necessary to keep the quality of raw meal / fuel stable.

Kiln Shutdown Period: The time is generally 35-40 days, and the construction, erection and commissioning shall be organized and implemented by the cement plant.

Conclusion

This kind of upgrade was carried out on the basis of the original high output. It achieved a large increase in production (average 19% or more), and the corresponding specific power consumption and heat consumption decreased. It showcases the advances in KHD technology and is a win-win, which is of great significance for the cement industry and worth learning and spreading.