REPOR TRESUMES ED OM 582 VT 003 669 TECHNOLOGICAL CHANGES IN THE CEMENT MANUFACTURING INDUSTRY. BY- WESSON, CARL E. CALIFORNIA STATE DEPT. OF EMPLOYMENT, SACRAMENTO BUREAU OF EMPLOYMENT SECURITY, WASHINGTON, D.C. PUB DATE OCT 66 EDRS PRICE MF-$0.25 HC-$1.32 31P. DESCRIPTORS- *TECHNOLOGICAL ADVANCEMENT, *AUTOMATION, *CEMENT INDUSTRY, JOB ANALYSIS, COMPUTERS, EMPLOYMENT TRENDS, EMPLOYMENT OPPORTUNITIES, *OCCUPATIONAL INFORMATION, THE PURPOSE OF THIS STUDY IS TO PRESENT A PRELIMINARY PICTURE OF OCCUPATIONAL CHANGES BROUGHT ABOUT IN THE MANUFACTURE OF CEMENT AS A RESULT OF INTRODUCING AUTOMATED EQUIPMENT. ONE AUTOMATED AND SEVERAL CONVENTIONAL TYPE CEMENT PLANTS WERE STUDIED. ANALYSIS OF DATA OBTAINED THROUGH RESEARCH AND DATA COLLECTED DURING THE STUDY REVEALED THAT MANUFACTURERS OF CEMENT, LIKE THOSE IN SO MANY OTHER INDUSTRIES, ARE AUTOMATING THEIR MANUFACTURING PROCESSES. THE CEMENT INDUSTRY IS GOING THROUGH ONE OF THE GREATEST REMODERNIZATION ERAS THAT COULD BE EXPERIENCED BY ANY INDUSTRY. INFORMATION IS PROVIDED ON THE OCCUPATIONAL STRUCTURE OF THE CEMENT PLANT BEFORE AND AFTER INTRODUCTION OF A COMPUTER CONTROL SYSTEM, THE JOSS ELIMINATED AND NEW JOBS CREATED, THE KIND OF WORK THE NEW JOBS ENTAIL, THE KINDS OF KNOWLEDGE AND SKILLS THE NEW JOBS DEMAND, AND THE SOURCE OF WORKERS FOR FILLING THE NEW JOBS. HISTORICAL MATERIALS, *PROCESS FLOWCHARTS, AND OTHER PERTINENT INFORMATION ARE PRESENTED FOR EACH PROCESS IN THE AUTOMATED PLANT DESCRIBED. CHANGEOVER TO AN AUTOMATED SYSTEM IN THE ABC CEMENT COMPANY INDICATED A DECREASE IN EMPLOYMENT OF ABOUT 13 PERCENT. AVERAGE PRODUCTION WAS INCREASED. (PS) United States Employment Service October 1966 Technological Changes in the Cement Manufacturing Industry Department of Employment State of California U. S. DEPARTMENT OF LABOR CALI FORM A STATE EMPLOYMENT SERVICE W. WILLARD WIRTZ, SECRETARY ON idled ii ith U. S.1 m No\ nic IIISe'ri'icc MANPOWER ADMINISTRATION Edmund G. Brown 1UREAU OF EMPLOYMENT SECURITY Governor C.0 WASHINGTON, D. C. 20210 (I) .1 lbert B. T ieburg Director C U.S. DEPARTMENT OF HEALTH, EDUCATION & WELFARE OFFICE OF EDUCATION THIS DOCUMENT HAS BEEN REPRODUCED EXACTLY AS RECEIVED FROM THE PERSON OR ORGANIZATION ORIGINATING IT.POINTS OF VIEW OR OPINIONS STATED DO NOT NECESSARILY REPRESENT OFFICIAL OFFICE OF EDUCATION POSITION OR POLICY. TECHNOLOGICAL CHANGES IN THE CEMENT MANUFACTURING INDUSTRY Ir CALIFORNIA STATE EMPLOYMENT SERVICE DEPARTMENT OF EMPLOYMENT ALBERT B. TIEBURG, Director TABLE OF CONTENTS Page Foreword History of Cement 1 Processes in the Manufacture of Cement: Traditional Procedures 2 Isometric Chart: Processes in the Manufacture of Cement 4 Discussion of Computer Control System 5 Processes in the Manufacture of Cement: Automated Procedures 6 Staffing Requirements 12 Jobs Created by Installation of Automated Equipment 13 Arrangement and Content of Job Descriptions. 14 Job Descriptions and Worker Requirements 15 Summary 21 Bibliography 22 Index of Occupational Titles 23 Appendix 24 iii FOREWORD The purpose of this study is to present a preliminary picture of occupational changes brought about in the manufacture of cement as a result of introduction of automated equipment. In investigating the changes that occurred in the plant, the questions formu- lated were restricted to providing information in the following areas: occupa- tional structure before and after introduction of the equipment; the jobs dis- placed and new jobs created; the kind of work the new jobs entail; the kinds of knowledge and skills the new jobs demand; and the source of workers for filling the new jobs. The findings of the study relate only to the automated plant described and do not necessarily reflect the experiences of other plants in the industry. His- torical material, process flow charts, and other pertinent information are pre- sented for each process to provide for a better understanding of the processes discussed. Additional data for the study was obtained from conventional-type cement plants and from articles and other secondary sources. Although this study is limited, we believe that even with its limitations it can be helpful to public employment offices and others through adapting the in- formation it contains to similar situations and circumstances in their own com- munities. The study was prepared by Carl E. Wesson, occupational analyst, under the supervision of Kenneth J. Bohn, field center supervisor of the California Occu- pational Analysis Field Center of the California State Employment Service in cooperation with the Branch of Occupational Analysis of the United States Employment Service. Grateful acknowledgement is made to the organizations and their staff who cooperated in the preparation of this brochure. Without their contributions and assistance it would not have been possible. HISTORY OFCEMENT Ever since man started to build, at the dawn of quarries on the Isle of Portland, England. Joseph Asp- civilization, he has searched for better bondingagents din is given credit for making the first portlandce- with which to hold together the rocks andstones used ment, and he is generally recognized as the father of in construction. The Egyptians used impuregypsum the modern portland cement industry. 2 plaster as mortar in pyramid construction. Slaked lime Aspdin appears to have been the first to realize that was used by the Greeks, and the Romans probably superior hydraulic propertieswere obtainable by learned of its utility from them. Both the Greeks and harder burning, that is, to proper fusion, instead of Romans made a pozzolanic mortar by mixing finely solely by calcination aswas long the practice. How- ground volcanic material with lime, sand, andwater. ever, he followed the previous practice of pulverizing Pozzolana hardens by reacting chemically with the by slaking and removing by hand larger pieces ofun- lime. The name derives from the Italiantown Pozzuoli, slaked harder-burned clinker. It remained for Isaac where a suitable volcanic tuffwas found. The Romans Johnson to discover, about 1845, that the harderpar- also used powdered pottery fragmentsas pozzolana. ticles after weathering and suitable mechanical grind- The pozzolanic cements made by mixing suchmate- ing yielded a cement of superior qualities. Johnson, rials with lime and waterwere found to be resistant if therefore, is more nearly the discoverer of theport- exposed to water, andwere for a long time the only land cement we know. cements known to be suitable for such exposure. The cement industry in this country began with Pozzolanic cement was used in such structuresas the the discovery in 1818 of a natural-cement rocknear Pantheon, the famous Appian Way, the great system Chitenango, New York, by Canvass White, an engi- of aqueducts, and the Colosseum. neer on the Erie Canal. In 1825 cement rock was found Despite the early use of these materials, littlewas in Ulster County, New York, and in 1828a mill was known of their chemistry, andno substantial advance built in Rosendale, New York. In the spring of 1866 was made in the manufacture of lime and cement from three men from Allentown, Pennsylvania, formed the the time of the Romans until 1756. In thatyear John Cop lay Cement Company and locateda mill near that Smeaton, who had been employed by the Englishgov- city. Mr. Saylor, one of the partners, beganto experi- ernment to build a lighthouse in the English Channel, ment on portland cement from the rock in the quar- discovered that an impure or clayey limestone, when ries. After a great number of experiments,true port- burned and slaked, would harden intoa solid mass land cement was produced in 1875. Thiswas the small under water as well as in air. This discovery of beginning of the American portlandcement industry. Smeaton's led the way to rapid improvement and de- velopment in the lime and cement industries. Modern portland cement is a finely pulverizedma- In 1796 James Parker, of Northfleet, Engl&nd, ob- terial consisting principally of certain definitecom- pounds. tained a patent for the manufacture ofcement, which he aptly named "roman cement." Parker'sprocess Methods of production have naturally changed consisted of burning certain stoneor clayey products greatly over the years. Early firing was in stationary, called "nodules of clay" inan ordinary limekiln, and intermittently operated kilns. Productionwas on a then grinding the clinkers toa powder. Cement made small scale and the cementwas ground with millstones. in this way did not absorbwater and crumble. The Kilns underwent various changes, but the most strik- process rapidly gained favor among engineers and ing was the introduction of the rotary kiln. In 1877 builders, and natural-cement plantssprang up all over T. R. Crampton obtained a British patenton a rotary the continent of Europe, in England, and later, about kiln process for cement, but itwas not a success. 1818, in the United States. Frederick Ransome obtained British and U.S. patents in 1885 and 1886 for a process that achieved first In 1824 Joseph Aspdin took outa patent in England suc- for the manufacture of cess in the United States and led eventually to com- an improved cement, produced plete adoption of the rotary kiln for production of by calcining a mixture of limestone and clay. To the portland cement in this country. In Europe the resulting powder he gave thename "portland cement," con- because when it hardened it produced tinuously operating shaft kiln has remaineda com- a yellow-gray petitor. mass resembling in appearance a stone found in various 2 Calcination: A process in which volatile material, such as carbon dioxide, 1 Clinker: The product resulting from calcining raw, pulverized stone in is expelled from limestone by the application of heat to reduce the a kiln of a cement plant to a point of incipient fusion. limestone to a powder. 1 PROCESSES IN THE MANUFACTURE OF CEMENT TRADITIONAL PROCEDURES The basic steps in the manufacture of cement are as material leaves the primary crusher in pieces no larger follows: than seven inches in diameter. 1. Excavation of raw materials Depending on the moisture content of the raw ma- 2.