Cement/Lime Production

with recommended kit #2 of model 350 portable emissions analyzer
(it is suggested that the CO2 module is included in this kit)

The material known as cement consists of ground cement clinker mixed with gypsum. It is the end product of a firing process in the cement furnace. Raw materials are limestone (CaCO3) and additives such as clay, ash, or sand. Powdered coal, oil, and waste material (used tires) are utilized as fuel. The major process steps are:

Grinding of the raw materials, drying of the material using hot exhaust gases, heating of the raw meal up to 1472°F with removal of CO2, firing in a rotating kiln, cooling, mixing with gypsum, and grinding to cement. The exhaust gases pass through an evaporation cooler and some gas cleaning plants (not shown in the figure below) including an electrostatic filter before they are released to the atmosphere.

Use of gas analysis for e.g.

Optimization of the evaporation cooler operation
Protection of the electrostatic filter by monitoring CO
Control of sampling probe position of the stationary analyzer
Monitoring emission concentrations for compliance with regulations

Process flow chart of cement production with measuring points

Measuring point locations and analysis tasks

  • MP 1 between calcinator and cooler to determine a plant balance
  • MP 2 between cooler and filter to determine plant balance and filter efficiency
  • MP 3 at the stack for emission monitoring (compliance with regulations)


Component MP 1 in raw gas MP2 and 3 in clean gas
Typ. values Meas. range
Typ. values Meas. range
O2 up to 10% 0 .. 21 % see raw gas
CO 100..10000 ppm 0 ..10000 ppm
(0,1 .. 20%)
see raw gas
CO2 ca. 20 .. 40% 0 ..25%

(0,1 .. 100%)

see raw gas
SO2 low 0 .. 5000 ppm
NOx 200..700 ppm 0.. 5000 ppm
Dust up to 100 g/m3 up to 100 mg/m3
Temp. 572-752°F 212-302°F

Typical values of a cement production plant


  1. High dust loading of raw gas and sometimes of ambient air
  2. Very high concentration of CO2, partially outside the measuring range
  3. The O2 sensor is, at high O2 concentrations, cross-sensitive against high CO2 concentrations
  4. Gas flow measurements are not possible at high dust concentrations and high gas flow velocities
  5. The sampling probe must be grounded when mounted at a stack built of bricks!
  6. Depending on the kind of fuel also limit values of lead (as dust) as well as of thallium and cadmium may be relevant.

Recommended for this application Kit #2 of model 350 portable emissions analyzer

A best selling kit for NOx testing on boilers and burners

  • Includes: O2, CO, NO, NO2 (NOx) and automatic fresh air purge valve (max of 6 sensors)
  • Control Unit with back-lit display and integrated printer
  • Peltier gas chiller and water removal system
  • 6-foot remote control cable
  • 7-foot hose with special patented Teflon-lined hose and 12" probe
  • Basic Excel® Software
  • Spare parts & carry case & calibration certificate