CICEET Progress Report for the Period 8/01/00 through 1/31/01

Project Title:

Development of beneficial use alternatives for the management of dredged, contaminated sediments

Principal Investigators:

Bryan J. Magee, Ph.D.
Research Assistant Professor
University of New Hampshire
bryan.magee@rmrc.unh.edu

Kevin H. Gardner, Ph.D., P.E.
Research Assistant Professor
University of New Hampshire
kevin.gardner@unh.edu

 

I. Accomplishments

A. Scheduled Tasks

The initial goal of this project was to beneficially use contaminated dredged sediments as partial feedstock materials in the manufacture of two construction materials; namely Portland cement and pozzolanic supplementary cementitious materials. To meet this goal, the following 9 tasks were scheduled in the initial proposal document as submitted to CICEET:

  • Task 1 — Literature Review
  • Task 2 — Sediment Characterization
  • Task 3 — Sediment Pre-conditioning
  • Task 4 — Portland Cement / Pozzolanic Material Manufacture Study
  • Task 5 — End Product Performance Study
  • Task 6 — Portland Cement Manufacture: Pilot Scale Study
  • Task 7 — Economic Study
  • Task 8 — Software Development
  • Task 9 — Dissemination Program

B. Progress on Tasks

Progress made on each task is discussed in the following sections:

Task 1 — Literature Review

Two new students — Jennifer Dalton and Mindy Weimer — have been recruited to work on this research project. Both students are currently reviewing literature sources relevant to this topic. The focus of Miss Dalton’s efforts in this regard is the manufacture of Portland cement, particularly at the laboratory-scale, and the use of waste and alternative materials in this manufacturing process. Miss Weimer’s review efforts are concentrating on literature sources related to the fate of contaminants — particularly those typically found in dredged sediments — during high temperature processes such as cement manufacture.

Task 2 — Sediment Characterization

Samples were collected in collaboration with the New York State Department of Environmental Conservation’s Sediment Assessment and Management Section, and the NY Harbor Dredging Taskforce. Sampling was conducted along the Harlem River using a standard Ponar sampler. Three five-gallon samples were obtained from three different locations, all of which were typical depositional environments. The first sample was taken in approximately three feet of water at Inwood Hill Park, approximately 1/10 of a mile from the Henry Hudson Bridge (see Figure 1).

Figure 1


Samples two and three were taken from the east and west sides, respectively, of the Harlem River at the 155th St. Bridge (Macoms Dam Bridge). Samples were place in plastic 5-gallon buckets and stored at 4oC for future analysis (see Figure 2). The three samples collected were prepared for total elemental analysis using Neutron Activation Analysis (NAA) by drying and crushing 5-gram sub-samples using a mortar and pestle. NAA is a method by which most elemental concentrations can be determined very accurately. This work is being conducted by the Ward Center at Cornell University and is being conducted at no charge as part of the DOE’s Reactor Sharing Program. We are currently conducting preliminary analyses to investigate the utility of NAA for determination of trace elements such as mercury as well as the major elements such as Si and Al in the sediment matrix.

Figure 2


As part of our collaboration with the NYS DEC (see Task 4 for further details), the DEC’s NY Harbor Dredging Team supplied UNH with a summary of all data that has been collected on the sediments of NY/NJ Harbor. The DEC is currently undertaking a multi-million dollar effort to sample sediment, water and biota in the NY/NJ Harbor; an effort termed the Contaminated Assessment and Reduction Program (CARP). Although this data has not yet been released, it will be sent upon its availability. The DEC also sent along a CD-ROM database authored by the US Army Corps of Engineers and Science Applications International Corporation (SAIC) and titled "Harbor Environmental Data Management System" (HEDMS). HEDMS is an ArcView extension (so is GIS-based) and includes data primarily from the EPA/Corps/NOAA ’93-’94 EMAP (Environmental Monitoring and Assessment Program) study. These data and resources will be valuable in the assessment of the applicability of the process that is the subject of this research. It will be important to select sediments that represent the range of material that will be dredged from the NY Harbor, in terms of contaminant burdens, major elemental composition, and physical properties, and to know how the sediments we sample compare with those extensively sampled and analyzed in these studies.

Additional characterization work has commenced, with Jennifer Dalton having committed a considerable amount of time gaining expertise with quantitative X-Ray Diffraction (XRD) methods. Several samples of sediment have already been analyzed qualitatively, and work is undergoing to generate quantitative results from these endeavors. In addition, Mindy Weimer has analyzed the collected samples from loss-on-ignition, and has spent time learning to use the pH-stat leaching system and the Inductively-Coupled Plasma Atomic Emission Spectrometer for metals analysis. The first pH-dependent leaching curves to result from this work are expected by the end of February.

Task 3 — Sediment Pre-conditioning

The bulk of the contaminated dredged sediments obtained from the NY/NJ harbor are stored in a refrigeration unit within the materials laboratory. As samples are removed for testing, the following pre-conditioning steps routinely performed include: (i) de-watering the material in an oven (approximately 60oC for 24-hours); (ii) crushing the resulting friable lumps of sediment in a mortar and pestle; and (iii) sieving the samples (using a 75µm sieve) to remove any oversized and unwanted debris. Work in this task is also commencing to determine the chloride content of the dredged material in its original state. This work will determine whether sediment washing is a further pre-conditioning requirement.

Task 4 — Portland Cement / Pozzolanic Material Manufacture Study

Given in the following sections is an overview of the work undertaken in this task to date.

Collaborative efforts with Blue Circle Cement and the NY State DEC

Considerable effort has been input into establishing an alliance with both Blue Circle Cement and the NY State DEC, both of whom have a similar and mutual interest in the potential for using dredged material as a partial feedstock in manufacturing cement. Collaborative efforts initiated on December 6, 2000, when all three parties met at Blue Circle Cement’s plant at Ravena, NY. The outcome of this meeting was extremely positive, with both Blue Circle Cement and NY State DEC expressing a willingness to become involved with support this CICEET-funded research project — their ultimate goal being to adopt the proposed technology, should it prove successful, on a full-scale. Blue Circle Cement pledged support in the form of technical support, the provision of raw materials, and performing characterization studies on cement samples produced in the laboratory. NY State DEC’s pledged support in the form of providing technical support, helping to address future permitting issues, and providing existing dredged sediment information and analysis. Since the initial meeting, collaborative efforts have continued using conference calls and electronic communications. Since the beginning of this alliance, interest has additionally spread to the U.S. EPA and Army Corps.

Due to the potential impact of developing a successful utilization for dredged materials in cement manufacture, it was decided that the portion of the study exploring the production of pozzolanic materials be dropped from the research scope.

Formation of Expert Technical Group

An Expert Technical Group (ETG), consisting of the following members, was formed to oversee the execution of the research project:

  • Taylor Eighmy, University of New Hampshire
  • David Gress, University of New Hampshire
  • Alyse Peterson, New York State Department of Environmental Conservation
  • Dennis Wolterding, New York State Department of Environmental Conservation
  • Robert Meader, U.S. Army Corps of Engineers
  • Eric Stern, U.S. Environmental Protection Agency
  • Lorraine Roberts, Blue Circle Cement

Proposal preparation

Considerable work has additionally been input into the development of a secondary proposal document to be submitted to the New York State Empire Development Corporation (EDC). Based on the findings of the CICEET-funded research, the funds requested in this proposal document are to aggressively promote the technology developed in the CICEET-funded research towards adoption as a bona fide management strategy for dredged materials. Monies will be requested to execute the following work:

 

  • A feasibility study that addresses the logistics and capital expenditures associated with adopting this technology at the Blue Circle Cement Ravena plant;

  • A comprehensive pilot-scale manufacturing study at a professional testing facility such as the Construction Technology Laboratory (CTL), IL;

  • A full-scale demonstration manufacturing study at Blue Circle’s Ravena plant, which includes:
    • dredging and transportation of approximately 400 tons of sediment from NY/NJ harbor,
    • a 24-hour manufacture period using the alternative source of materials,
    • stack emission testing and ambient-air testing to ensure protection of worker and community health and safety and compliance with applicable permits,
    • formation of community and worker technical advisory groups,
    • testing of the end-products, such as cement and concrete products.

  • Technology transfer activities to allow other NYS cement manufacturing plants to capitalize on this approach, and to increase the impact of the alternative materials use on the management of sediments from NY Harbor.

This effort would combine the efforts of the UNH research team, Blue Circle Cement, the NY State DEC, the US EPA, the Army Corps of Engineers, Behan Communications (a public relations/communications firm) and AirNova (an air quality testing company). It is proposed to submit this proposal document to the Empire Development Corporation by the end of February 2001.

Feedstock material collection

On February 7, 2001, Kevin Gardner, Jennifer Dalton and Mindy Weimer visited Blue Circle Cement’s Ravena plant. The purpose of this trip was firstly to enable the graduate students to gain a better understanding for the scale and processes involved in the manufacture of Portland cement. A suite of materials necessary for the research project was also collected at this time. Materials collected included all of the raw materials used by Blue Circle Cement in their manufacturing process (i.e. limestone, shale, fly ash, bauxite, gypsum, iron) as well as slurry-phase raw material mixture, produced clinker and Portland cement.

Task 5 — End Product Performance Study

This work is not scheduled to commence until the completion of Task 4.

Task 6 — Portland Cement Manufacture: Pilot Scale Study

Likewise, this work is not scheduled to commence until the completion of Task 4. It should be noted that owing to a very limited pilot-scale program being included in the CICEET research project, a more comprehensive study has been incorporated into the proposal document to be submitted to the EDC.

Task 7 — Economic Study

Considering no tipping fees charged, Blue Circle Cement would realize an estimated savings of approximately $400,000 per year for a 1.5% by mass raw material replacement with dredged materials (although this does not consider any capital costs required to handle the alternative material). Blue Circle completed an additional economic analyses considering being able to receive a $30/ton (dry weight) tipping charge. At this rate, they estimated $3,061,162 annual savings over their current materials feedstock. The $30/ton dry weight estimate is a reasonable estimate of what they might be able to charge to receive this material; at 137% moisture content, this translates to approximately $21/ton wet weight (as dredged).

Task 8 — Software Development

A spreadsheet as used by Blue Circle Cement has been obtained and is currently under review. For required characteristics of Portland cement, this spreadsheet calculates the exact quantities of feedstock materials to be incorporated into the manufacturing process. A review of this spreadsheet is underway, and Jennifer Dalton is currently working with Blue Circle Cement to tailor this spreadsheet to meet the needs of the current research project — i.e. to find the optimum dosage of dredged sediments.

Task 9 — Dissemination Program

To date, two dissemination activities have been undertaken. On December 3-6, 2000, Bryan Magee and Kevin Gardner attended a conference on "Dredged Material Management: Options and Environmental Considerations," at the Massachusetts Institute of Technology, Boston. A poster presentation entitled "Beneficial Use of Contaminated Dredged Sediments in the Manufacture of Conventional Portland Cement" was delivered at this meeting. A technical paper on the topic has additionally been submitted to an international conference entitled "Beneficial Use of Recycled Materials in Transportation Applications," to be held in Washington D.C. on November 13-15, 2001.

C. Difficulties Encountered

A muffle furnace has been purchased in order to manufacture small quantities of Portland cement at the laboratory-scale. As the temperature requirement for this process are in excess of 14000C, a muffle furnace meeting these high-temperature requirements was purchased. Unfortunately, however, the electrical requirements for this apparatus (240V, 40A) cannot be currently met in any of the laboratories available to the research team. This problem is currently delaying the Portland cement manufacture portion of the study, as work to install the required electrical components in Kingsbury Hall has not been completed.

D. Anticipated Success in Meeting Project Objectives in Scheduled Project Period

Taking into account the modifications made to the original project objectives, it is anticipated at this time that the laboratory-phase of the research project will be completed within the scheduled project period.

E. Preliminary Data

As the majority of work to date has concentrated on reviewing relevant literature sources, collecting and characterizing dredged materials and the raw materials required for cement manufacture, and preparing a proposal document to further develop the scope of this research project, the PI’s have elected not to report any preliminary data at this time. Instead, it is planned to wait until the next reporting period to present more meaningful data related to the characteristics of cement manufactured with dredged materials.

II. Tasks and activities for next reporting period

A. Tasks for the Next Reporting Period

The following tasks are planned for the next reporting period:

  • Execute a full qualitative analysis of the dredged material samples as collected from the NY/NJ harbor;
  • Execute a full qualitative analysis of each of the individual feedstock materials as collected from Blue Circle Cement’s Ravena plant;
  • Evaluate a range of dredged material dosages that can practically be used in cement manufacture;
  • Recreate feedstock material slurry using dredged material dosages covering permissible range;
  • Commence Portland cement manufacture at laboratory-scale using muffle furnace.

B. Work Plan to Accomplish Tasks

An overview of the work plan to accomplish the proposed tasks for the next reporting period is given in Table 1.

 

Work will continue to focus on the characterization of the dredged material samples already collected. In addition, work will commence immediately to characterize the raw materials collected from Blue Circle Cement. Analysis methodologies used in this work will include X-Ray Diffraction and Neutron Activation Analysis. By also developing the required software (see Section B, Task 8 above), the potential replacement dosages for dredged materials will be calculated. The next step of work will then be to produce raw material slurries (i.e. exact combinations of feedstock materials — including the dredged materials). As soon as these tasks have been completed, and assuming the purchased muffle furnace is operable, exploratory work to manufacture small quantities of cement clinker will begin. The results of these endeavors will be reported in the close of the next reporting period.

C. Concerns or Difficulties

No potential concerns or difficulties are predicted at this time.

III. Expenditures

Expenditures at this time are in the range anticipated for the work accomplished to date.