Process Analyzers for Stable, Long-Term Measurement of High-temperature, Dust-laden Gases

Introduction

Cement is made by heating calcareous and argillaceous materials to a temperature between 1100 and 1500°C. As this process uses massive amounts of energy, various energy saving measures are taken, including the measurement of oxygen concentrations in exhaust gases to control combustion. To protect the environment, electrostatic precipitators (ESPs) reduce dust emissions and analyzers measure concentrations of nitrogen oxides (NOx), sulfur dioxide (SO₂), and other pollutants.
Analyzers installed for this purpose are expected to provide stable, long-term performance even under harsh process conditions. Yokogawa process analyzers can be used to measure O₂ and CO at the upper end of a kiln or at the outlet of a flash furnace, where high-temperature, dust-laden gases flow. They can also be installed at the outlet of an ESP to monitor dust concentrations and optimize efficiency, and in a smoke stack to measure NOx, SO₂, and O₂.

 

Expected Benefits

• Measures gas concentrations and dust concentrations in cement plants
• Reduces operating costs

 

Sample Conditions at Measurement Points

 

Process Overview

Cement Manufacturing Process: Raw materials such as calcareous and argillaceous materials are dried, blended, and pulverized in a mill to create powdered material. The powdered material is preheated and decarbonated in a suspension preheater and flash furnace, and calcinated in a kiln to produce clinker. The clinker is cooled, mixed with gypsum and ground in a finish mill to produce cement.