Location:
OIL; SOLID WASTE MANAGEMENT;
Scope:
Background;

OLR Research Report


January 12, 2012

 

2012-R-0025

PLASTICS TO OIL TECHNOLOGY AND CRRA

By: Kevin McCarthy, Principal Analyst

You asked for a discussion of technologies that convert plastics to oil or other fuels, and the potential carbon dioxide (CO2) emission reductions and other environmental benefits that would be derived if the Connecticut Resources Recovery Authority (CRRA) were to use these technologies. Your questions were prompted by a constituent who brought a specific plastics-to-oil conversion technology developed by a Japanese firm to your attention.

Much of the technical information in this memo is taken from an April 2011 report prepared for the American Chemistry Council (ACC, an industry association), which is available at http://plastics.americanchemistry.com/Plastics-to-Oil.

SUMMARY

There are a variety of technologies that convert plastics to oil or other fuels using a process called pyrolysis. While there are commercial plastics-to-fuels (PTF) facilities around the world, the existing PTF facilities in the United States are pilot stage or smaller facilities.

CRRA recycles the plastics that come to its recycling facilities, such as soda bottles and milk jugs. CRRA sells these plastics under a contract that runs until 2018 with a firm that recycles them. As a result, CRRA has not considered PTF technologies to date. CRRA incinerates other plastics that are not recycled at its facilities to generate power.

It appears that PTF technologies could be a cost-effective complement to recycling, producing fuel at prices substantially below current fuel prices. The conversion process itself creates few emissions. However, the oil or other fuel produced by the PTF technology will produce substantial CO2 emissions when it is burned.

PLASTICS TO OIL TECHNOLOGIES

Manufacturers create plastics by converting feedstocks such as oil or natural gas into polymer resins (i.e., long chains of hydrocarbons). Among the most common types of resins are:

1. polyethylene terephthalate (PET), used in products such as soda bottles;

2. high-density polyethylene, used in such products as grocery bags and milk jugs;

3. low density polyethylene (LDPE), used in products such as plastic bags and the rings that hold soda cans;

4. polyvinyl chloride (PVC), used in products such as non-food bottles and children's toys;

5. polypropylene, used in food containers and other products; and

6. polystyrene, used in Styrofoam and packaging peanuts.

Plastics are increasingly recycled, and many consumer products have a symbol (a triangle around a number) that indicates the type of resin they contain to facilitate recycling. Further information on this labeling system is available at: http://en.wikipedia.org/wiki/Resin_identification_code.

The ACC report notes that despite the advances over the recent years in recycling plastics, part of the plastic waste stream cannot be recycled due to contamination, lack of markets, or the inability to separate plastics. However, a variety of conversion technologies designed to manage non-recycled plastics have been developed, and commercial scale facilities to convert plastics into oil and fuel have been established in Europe and Asia; these technologies are also being introduced in the United States.

The ACC report identified 23 manufacturers of PTF technology. Common features of these technologies include:

1. pretreatment, such as cleaning and shredding the plastics;

2. using pyrolysis to convert the plastics to a gas;

3. distilling the gas into a liquid;

4. removing the acids that form in the breakdown of some scrap plastics that can be corrosive to the PTF systems and the engines that will consume the fuel; and

5. separating, refining, and final blending of the fuel, which can be done on site or by a third party depending on the system design.

Pyrolysis is process involving thermal treatment, and sometimes pressure, to convert plastics to a fuel product. It is related to the cracking process used to refine crude oil into petroleum products. The gas produced by this process can be used to power the distillation and refining processes as well as being converted into oil or other fuels.

Figure 1, taken from the ACC report, provides a schematic representation of how PTF facilities work.

Figure 1: PTF Facility Operations

Each of the PTF technologies is unique in terms of the type of scrap plastics the systems can handle. For example, the technology your constituent identified does not handle soda bottles and other PET products or PVC products. This may reflect the fact that the fuel yield for PET is 30%, compared to 70% for LDPE and 90% for polystyrene and polypropylene. In addition, during conversion PVC produces hydrochloric acid, which is highly corrosive.

The technologies also differ in the type of fuel they produce. Some produce diesel that can be used for vehicles, other produce a gasoline-diesel fuel blend that needs further refining. Some generate a product similar to low-sulfur oil that needs to be refined, but can become a variety of products. All of the technologies produce char, a mixture of solids that include carbon black (a marketable product) as well as contaminants.

While there are several commercial PTF facilities in other parts of the world, the industry is in its infancy in this country. Table 1, taken from the ACC report, describes PTF technology manufacturers based in the United States or Canada. Firms marked with an asterisk (*) have pilot facilities in operation, while the others have very small scale (bench) production facilities.

Table 1: North American PTF Technology Manufacturers

Firm

Location

Output

Agilyx*

Tigard, OR

oil

Climax Global Energy*

Allendale, SC

oil

Envion*

Washington, DC

oil

GEEP*

Barrie, Ontario

mixed fuels

Green Mantra Recycling

Technology

Toronto, Ontario

wax, lubricants

Natural State Research

Stamford, CT

mixed fuels

Northeastern University

Boston, MA

gas

Plastic2Oil (JBI, Inc.)*

Niagara Falls, NY

mixed fuel

PolyFlow

Akron, OH

mixed fuel

Recarbon Corp.

Kingston, PA

oil

Vadxx*

Cleveland, OH

oil

CRRA AND PLASTICS TO OIL TECHNOLOGY

As its name indicates, CRRA operates facilities that recover economically valuable resources, including some plastics, from solid waste generated in the state. CRRA has a contract with ReCommunity (formerly Casella) under which all of the plastics that come into CRRA's recycling facilities are sold to ReCommunity. ReCommunity pays a per ton fee for all of the recyclables (plastics, paper, and metals), as well as a share of the revenue it earns when it sells these products to various manufacturers. The recycled PET containers are turned into carpet fiber and fabrics while the HDPE containers are returned to the market as other HDPE containers. This contract runs until 2018 and as a result CRRA has not investigated PTF technologies.

After the recycled materials are removed, the remaining waste goes to CRRA waste-to-energy facilities that incinerate the waste to produce electricity. The plastics that are not recycled as well as other municipal solid waste are burned in these facilities. Connecticut requires electric companies and competitive electric suppliers to get part of their power from renewable resources and the electricity from the waste-to-energy facilities is considered a class II renewable resource. As a result, the power that is produced by these facilities earns a small premium over the price of wholesale electricity.

The ACC report finds that PTF facilities could prove an economic complement to plastics recycling, although it notes that in the past the PTF technology manufacturers have had difficulties in scaling up their facilities and controlling the quality of the fuels they produce. The PTF manufacturers surveyed for the ACC report suggested that they could produce oil or other fuels for as little as 75 cents per gallon, if they did not have to pay for the plastic.

The environmental benefits of PTF technologies are less clear. The conversion process itself creates few emissions. For example, the manufacturer identified by your constituent claims that his technology puts about 196 grams of CO2 into the air for every kilogram of plastics converted. In contrast, incineration puts about 1,700 grams of CO2 per kilogram of plastics burned, as well as some nitrous oxides and fine particulates.

However, the oil or other fuel produced by the PTF technology will produce substantial emissions when it is burned. For pollutants such as nitrous oxides, the amount of emissions will depend on how the fuel is used, e.g., burning heating oil in older furnaces will produce more emissions than burning gasoline in vehicles with catalytic converters. The CO2 emissions of burning oil or other fossil fuels are substantial, regardless of the specific fuel or technology. For example, burning heating oil or diesel fuel produces about 22.4 pounds of CO2 per gallon of fuel burned, or approximately 3,585 grams of CO2 per kilogram of fuel.

KM:ro