Cement production

Patent metadata

Field	Value
Publication number	US-12448327-B2
Application number	US-202217569496-A
Country	US
Kind code	B2
Filing date	Jan 5, 2022
Priority date	Nov 2, 2018
Publication date	Oct 21, 2025
Grant date	Oct 21, 2025

Abstract

The present invention provides a method and system for manufacturing cement wherein ground particles of cement and calcium sulfate are subjected to infrared sensors, laser sensors, or both, so that emanated, irradiated, transmitted, and/or absorbed energy having wavelengths principally within the range of 700 nanometers to 1 millimeter can be monitored and compared to stored data previously obtained from ground cement and sulfate particles and preferably correlated with stored strength, calorimetric, or other data values, such that adjustments can be made to the mill processing conditions, such as the form or amounts of calcium sulfate (e.g., gypsum, plaster, anhydride), or cement additive levels. The strength and other properties of cement can be thus adjusted, and its quality can be more uniform.

First claim

It is claimed:

1. A method for manufacturing cement, comprising:
(A) introducing, into a grinding mill, raw materials comprising clinker, a source of sulfate chosen from gypsum, plaster, calcium anhydrite, or a mixture thereof; grinding the raw materials, to produce a ground blend of particles comprising ground clinker and calcium sulfate; and separating the ground blend of particles within a classifier whereby a first portion of the particles or the finished cement is removed from the grinding mill and whereby a second portion of the particles is recirculated for further grinding in the grinding mill;
(B) providing at least one infrared sensor system comprising a processor that is communicative with processor-accessible memory, the at least one infrared sensor system effective to detect at least one of emanation, reflectance, transmittance, or absorption of infrared energy in the range of 700-1400 nm by or through the ground blend of particles or finished cement provided in step (A), and generating output signals corresponding to the detected energy;
(C) comparing, using the processor, the output signals generated in step (B) to data stored in the processor-accessible memory, the stored data comprising output signal values previously obtained from the at least one infrared sensor system measuring the emanation, reflectance, transmittance, or absorption of energy in the infrared spectrum of 700-1400 nm, the stored data being correlated with a physical or chemical property of the corresponding finished cement, hydrated cement, or cementitious product made with the cement; and
(D) in response to the comparison in step (C), adjusting a grinding mill condition chosen from (i) adjusting amount and form of calcium sulfate introduced into the grinding mill in step (A); (ii) adjusting classifier settings thereby to change relative amounts of ground particles being removed from the grinding mill and being recirculated back into the grinding mill; (iii) adjusting amount, type, or both amount and type of cement additives introduced into the grinding mill; (iv) adjusting amount of water being introduced into the grinding mill; (v) adjusting amount of air provided by adjusting power or speed of a fan or blower connected to ventilate the mill; (vi) adjusting amount or type of supplemental cementitious material introduced into the grinding mill; or (vii) performing a combination of the foregoing adjustments of grinding mill conditions.

2. The method of claim 1 wherein the steps (A) through (D) are performed at least once every week.

3. The method of claim 1 wherein the steps (A) through (D) are performed at least once on a daily basis.

4. The method of claim 1 wherein the steps (A) through (D) are performed at least once on an hourly basis.

5. The method of claim 1 wherein the steps (A) through (D) are performed at least once every fifteen minutes.

6. The method of claim 1 wherein the steps (A) through (D) are performed at least once every five minutes.

7. The method of claim 1 wherein both the amount and type of cement additives introduced into the grinding mill are adjusted.

8. The method of claim 1 wherein the processor is programmed to adjust the introduction of chemical additives into the grinding mill in terms of type, formulation, amounts, dosage rate, or a combination thereof.

9. The method of claim 8 wherein the processor is programmed to adjust the rate by which specific chemical additives are introduced into the grinding mill.

10. The method of claim 1 wherein the processor is programmed to adjust cement additive dosage based on strength performance of cement, throughput of the mill, or combination thereof.

11. The method of claim 1 , wherein, a ground blend of particles or finished cement is sampled using an autosampler.

12. A cement provided by the method of claim 1 .

13. The method of claim 1 further comprising:
(A1) providing an indication chosen from audible alarm, visual alarm, monitor, hand-held display, text message, or email that a physical or chemical property or amount of the raw materials, the clinker, the source of calcium sulfate, the chemical additive, the supplemental cementitious material, or the finished cement has changed;
(B1) performing at least one test to determine a physical or chemical property of finished cement chosen from (i) strength test data, (ii) exothermic data, (iii) set initiation data, (iv) slump data, (v) dimensional stability data, (vi) air content data, (vii) prehydration level data, (viii) reduction or burn conditions data, (ix) cement particle size distribution data, or (x) a combination thereof;
(C1) detecting from finished cement tested in step (B1) using at least one sensor system chosen from infrared sensor system, laser diffraction sensor system, or both, the at least one sensor system providing output signals corresponding to the reflectance, transmittance, or absorption of energy by or through the ground blend of particles or finished cement;
(D1) storing both the test results of step (B1) and step (C1) above, into a database accessible by a processor; and
(E1) making an adjustment to a model predicting at least one of (i) through (viii), making an adjustment to a target value for at least one of (i) through (viii), or making an adjustment to both the model and the target value.

14. The method of claim 13 wherein the indication provided in step (A1) is a change in fuel source; a predefined deviation from a chemical property as measured by infrared, laser diffraction, quantitative x-ray diffraction, x-ray fluorescence, prompt gamma neutron activation or a combination thereof, a predefined deviation in mill temperature or humidity, a predefined deviation in raw materials entering the kiln, a change in a kiln processing condition, a change in a mill processing condition, or a notification that a manual or automated cement sample was taken.

15. The method of claim 13 wherein testing in step (B1) is done using an autosampler.

16. The method of claim 13 wherein the indication is a change in any predicted value derived from a comparison between an infrared signal and strength test data, exothermic data, set initiation data, slump data, dimensional stability data, air content data, prehydration level data, reduction or burn conditions data, cement particle size distribution data, or a combination thereof.

17. The method of claim 13 wherein an adjustment is made to a model predicting at least one of the physical or chemical properties of finished cement recited in step (B1) based on near-infrared signal output value.

Assignees

• Gcp Applied Tech Inc

Inventors

• Berodier Elise
• Tregger Nathan A
• Cheung Josephine H
• Myers David F
• Zhang Li
• Kazmierczak Dorota
• Roberts Lawrence R
• Silva Denise A
• Sibbick Richard
• Thomas Jeffrey
• Roberts Mark F
• Stoppa Riccardo
• Burns Elizabeth

Classifications

• C04B40/0032

  Controlling the process of mixing, e.g. adding ingredients in a quantity depending on a measured or desired value (B28C7/00 takes precedence) · CPC title

• Y02P40/10

  Production of cement, e.g. improving or optimising the production methods; Cement grinding · CPC title

• Y02P40/121

  Energy efficiency measures, e.g. improving or optimising the production methods · CPC title

• G01N33/383

  Concrete or cement · CPC title

• G01N21/4788

  Diffraction (for sizing particles G01N15/0205) · CPC title