Figure 4 Wet Process Kiln (St. Lawrence Cement Co.)
Click image to view a full size version.
Reference: (MacDonald et al., 1977).
4.2.2.3 Other Kiln Processes
Two other cement kilns and 2 lime kilns have been considered for PCB destruction.
| Company |
Kiln Type |
| cement |
| cement and lime |
| lime |
The Peerless Cement Company performed PCB test burns in their kiln in Detroit. The kiln had a residence time of 10 seconds at a temperature of 1270 to 1390°C. Destruction efficiencies average in excess of 99.99%. Intense local pressure including adverse reaction from the Canadian side of the border in Windsor Ontario caused the Company to cancel its plans to burn PCBs.
Energy Optimization presently have an application before the US EPA to burn PCB (contaminated oil) in a cement kiln near Pittsburgh, Pennsylvania. This company previously had applied to burn PCBs in a lime kiln in Branchton, Pennsylvania but have cancelled these plans.
A lime kiln in Hopewell, Virginia owned by Continental Can was evaluated for PCB destruction in 1976. The kiln was a 226 Mg/day rotary lime kiln 3.4 m in diameter by 80 m long operating at 1260°C. Their tests suffered several difficulties and PCB destruction has not been reconsidered since 1976. Destruction efficiencies were estimated at approximately 95%.
References: (Ackerman et al., 1981; EPA, 1981)
4.2.2.4 Aluminum Melting Furnace Co-Treatment
Aluminum Company of America (ALCOA)
P.O. Box 3567
Davenport, Iowa 52808
Contact: Marshall Sonksen
(319) 359-2754
ALCOA'S aluminum fabricating plant located near Davenport, Iowa (Riverdale) has a dual fuel (gas/oil) fired aluminum melting furnace that has EPA approval to burn PCB-contaminated waste oils stored at the Davenport facility. A test burn was carried out in July 1981 under the watchful eye of the US Environmental Protection Agency, and approval granted in November 1981. They are required to preheat the furnace to 1150°C prior to introducing the PCB waste oil, maintain excess oxygen at 3%, and maintain the combustion efficiency @ 99.9% as indicated by CO emissions. Their permit is limited to the 6-8 million litres of the 350 mg/kg PCB-contaminated waste oil collected by ALCOA prior to discovering the PCB contamination.
References: (Sonksen, pers. comm. 1982).
4.2.3 Shipboard Incineration
4.2.3.1 MV Vulcanus
Head Office: Chemical Waste Management Inc.
2131 Kingston Court S.E.,
Marietta, Georgia 30067
Contact: Al McCoy, PCB Sales Supervisor
(404) 952-0444
This is basically a traditional incineration method but aboard a ship at sea thus limiting the possible hazardous effects on any population.
The MV Vulcanus is a 100 m long by 14 m wide ship with a maximum draft of 7.4 m. The ship houses two high capacity liquid-injection incinerators which are capable of combusting PCB-contaminated wastes at a rate of 22 Mg/h and a flame temperature of 1500 to 1600°C. The ship has a tank capacity of 3700 tonnes and operates by loading the PCB waste into its 15 tanks on shore. The practice has been to travel to an EPA approved location in the Gulf of Mexico where the wastes are incinerated. An extensive monitoring system ensures that the PCBs are destroyed to 99.995%.
The Vulcanus can only incinerate pumpable liquids that contain solids smaller than 2 mm, although the design concept for costing purposes included a rotary kiln for solids. A chlorine content of 70% on the PCB molecule represents no incineration problem. The PCB waste must not be capable of attacking mild steel.
The Vulcanus has been operating successfully since 1972 in Europe and the USA. In recent EPA tests the Vulcanus incinerated 2 650 000 L of PCB transformer fluid to an efficiency of 99.999% without significant formation of dioxins.
Incineration at sea of chlorinated wastes has been practiced for several years in Europe. Operating experience in the form of routine burning of PCB liquids is nil at the present time. This technology can be considered to be in its middle stages of full testing. Moderate technical skill would be required for facility operation.
The capital investment required for such a facility would be at least $7 000 000 excluding land costs for an on-shore support facility based on the 1981 costing figures provided by E.T. Oppelt.
Operation of an incinerator ship over a one year period would require a minimum of $6 020 000 including cost of capital. Utilities, labour and maintenance would be the major operating cost contributors. This figure is based on the assumption that design concept is for a rotary kiln incinerator followed by a liquid injection incineration after-burner. Design feed rate is 6000 kg/h liquid PCBs or 3000 kg/h solids, and facility operates 12 hours per day, seven days per week. Operating costs were calculated by comparing costs for a Rollins incinerator to costs for sea disposal in a format similar to operating costs as given in EPRI Guidelines for Disposal by Thermal Destruction.
The cost of destroying one kilogram of PCB liquid would be $0.23 using such an arrangement.
The environmental impacts of the Vulcanus are similar to those of all other incinerators. Hazards are minimal for the worker or public provided adequate care is taken in running the process. The impact of incineration on the environment is lessened by the fact that it occurs at sea well removed from land and population. Repeated EPA testing has shown that shipboard incineration does not affect fish and other sea life.
The EPA has given permission for 2 shipboard incineration runs on the Vulcanus and is continually testing and monitoring the ship's incinerators. The Vulcanus is prepared for the commercial incineration of PCB liquid wastes once their testing program has been completed.
References: (Oppelt, 1981; Jordan, 1982; Chemical Waste Management Inc.).
4.2.3.2 Other Shipboard Incinerators
At-sea Incineration, Inc. (ASI)
534 East Putnam Avenue
Greenwich, Connecticut 06830
Contact: Barry S. Cogan
Tel: (203) 629-3711
At-Sea Incineration, Inc. will operate two incinerator ships, each containing two liquid injection incinerators. The rated throughput of each incinerator is 3.22 x 108 kW. Hazardous wastes will be incinerated at an EPA approved burn site east of Cape Henlopen, Delaware. ASI expects to have the two ships operational by early 1984.
References: (Hazardous Materials Intelligence Report, 1982). |
