A comprehensive substitute material program can create a pathway for a successful long-term operation that optimizes these raw materials and fuels

The cement manufacturing industry is a large-scale, mass-production process using high volumes of raw materials, such as limestone, clay or shale, sand, iron ore, and fuels, such as coal. The use of substitute raw materials and fuels (non-hazardous wastes) as a replacement for some of these "virgin" materials in the cement manufacturing process is not a new practice.

With the industry-wide market slowdown of the 1980s and declining cement prices, many facilities felt the push to maximize profits by minimizing production costs. Due to the large volumes of raw materials and fuels used in the manufacturing process, much of the production costs are attributed to the mining and processing of these materials. A few facilities found the acceptance of substitute raw materials and fuels to be the edge they needed to remain competitive in the market. Although many facilities attempted to capitalize on this idea, few expanded their program beyond a few substitute raw material or fuel streams.

One common theme was observed among facilities that were not able to evolve their substitution program into a viable business venture: the lack of a thorough management program. Often, facilities placed the entire management of the program on one person's shoulders without outlining definitive tasks for the various stakeholders in the process. Those that developed comprehensive management programs were typically more successful in growing the substitution program.

What follows is a framework that establishes the foundation for developing a program to manage substitute raw materials and fuels, hereafter referred to as substitute materials. Thorough program development and implementation can provide the necessary tools for a successful program.

Program basics To begin developing a management program for substitute materials, one must first define specific areas from which to develop the program. The following four areas are those that have typically been identified as the basics of such a management program (the aspects of each area are briefly outlined below to better define their scope):

- Initial facility evaluation/preparation;

- Substitute material stream evaluation process;

- Acceptance of substitute material shipments; and

- Program follow-up.

Evaluation and preparation Before any substitute materials can be evaluated, accepted, and used at the facility, certain evaluations must be conducted and preparations completed. Much of the success of the program depends on the quality of this initial phase. This initial phase consists of several steps necessary to ensure a complete evaluation of the facility's capabilities and potential pitfalls, and to prepare the site for the acceptance of the substitute materials.

The first step of the initial phase is to evaluate the regulatory permits for the ability to accept the substitute materials. This review should identify any potential language that would hinder acceptance of these substitute materials or otherwise limit the types and volumes received.

Federal, state, and local regulations must be reviewed in unison with the permits to ensure that all applicable regulatory requirements are addressed. A list of permit and regulatory requirements specific to the substitute materials program should be prepared for ease of reference. Once this initial review is complete, permit modifications may be necessary to allow for the acceptance of substitute materials.

Along with the regulatory review, a market analysis and business plan should also be developed that identify sufficient substitute materials from local industries to warrant the business venture. Like any good market analysis, the report should focus on materials acceptable in the cement process, their location with respect to the plant, competition for the material such as disposal facilities or other recyclers, and market pricing at these competitive options. Based on these data, a business plan can be developed to evaluate whether a sufficient materials market and price are available to justify a substitute material program.

Once it has been determined that the facility has both the regulatory ability to accept substitute materials and an adequate market for the business effort, the on-site management program must be developed. The program must be designed to adequately address three major procedures: substitute material evaluation, shipment acceptance, and post-receipt management.

In order to administer an effective program, several different departments and their respective personnel must be proactively involved in the process of evaluating, accepting, and managing substitute materials. No one person can ensure this process is completed.

With the involvement of multiple departments, the management of substitute materials can be optimized to provide the most benefit for the plant and minimize operational issues. Responsibilities for the program should be established with a common goal among all departments. An example of how departmental duties can be established is as follows:

- Program Coordinator administers the overall program to ensure that materials are thoroughly evaluated and managed.

- Laboratory evaluates the suitability and appropriate substitution rates of candidate materials for use in the cement process.

- Production evaluates storage and handling options and associated costs, and manages substitute materials once accepted at the plant.

- Maintenance reviews identified storage and handling options and determines any maintenance issues or costs that need to be addressed to manage the material.

- Engineering evaluates options and manages projects to enhance storage and handling of materials on-site. Also performs an economic evaluation of candidate materials to assist in pricing.

- Environmental evaluates the candidate material properties against the regulation and permits to determine if the material can be used at the plant, or if permit modifications are necessary.

- Health and Safety evaluates the proposed management for candidate materials to determine safety and worker protection options.

- Purchasing negotiates contracts and pricing, supplying necessary information for invoicing.

- Accounting tracks materials receipts and prepare invoices.

As shown, each department plays an important role in evaluating and tracking materials into and through the facility.

Material stream evaluation The next area to develop is the evaluation process for each new substitute material. The evaluation process must be completed in a timely manner by all departments in order to maintain customer service priorities. Tracking forms should be developed to compile all information on each material and to track timing for the evaluation process.

An example of the process to evaluate candidate materials is illustrated by Figure 1 (page 25). This process, along with the established departmental roles and tracking system, form the basis for an initial substitute materials evaluation program.

Acceptance of substitute material shipments An important element of a successful substitute material program is the efficient acceptance and unloading process once a shipment arrives at the facility. Detailed procedures for receipt of substitute material shipments should be developed during the initial facility review and preparation phase.

These procedures include shipment paperwork reviews, verification of the shipment amount received, location of the unloading and storage area, receipt analysis parameters, and unloading steps. These may be generic standard operating procedures for all materials or specific steps for each different substitute material received. The important issues are to ensure the material is the same as was originally evaluated and accepted, and that the customer's material is unloaded quickly and efficiently.

Program follow-up Once the materials are received, the plant must plan for the timely use of the material to avoid storage-related problems, such as excessive runoff and accumulation issues with the regulatory agencies. In most cases the cement laboratory can dictate the usage rate for any of the substitute materials by designing the raw material mix to optimize its use. Production must be flexible to allow for these design changes in order to use the substitute materials in a timely manner.

In addition, proper and timely invoicing is important for client relations and the economic viability of the program. A procedure must be developed in the initial facility preparations to forward shipment information, including weight tickets, to the accounting department for input and invoicing.

Summary Managing a comprehensive substitute material program is no simple matter. A successful program takes time and resources to develop. The foundation for a program includes identifying roles and responsibilities, creating procedures for evaluating and managing substitute materials, and developing tracking mechanisms to assure that both the facility's and customer's needs are met. Developing a program early on that meets a facility's site specific needs can create a pathway for a successful long-term program that optimizes the use of substitute raw materials and fuels.