Greenhouse Gas Emissions and Strategies for Change

Greenhouse Gas Emissions and Strategies for Change T. Akim Nilausen Nichole Brown

Advisor:
Dr. Gregory Carmichael
Department of Chemical & Biochemical Engineering Atmospheric Chemistry and Physics 052:163 University of Iowa Fall 1998

Summary
Carbon dioxide is the most abundant component of the suite of gasses called Greenhouse Gasses. Although CO₂ emissions are charged with causing global warming, some groups believe that CO₂ is good for the environment, and yet others contend that decreasing emissions will ultimately bring catastrophic consequences to the biosphere.

This web page will highlight the causes and problems associated with carbon dioxide emissions, and some innovative solutions to deal with existing and future CO₂ production

Contents
The Problem
The Causes
What We Are Doing About It
Links
References

The Problem
Since the beginning of modern, recorded history, the levels of Greenhouse Gases have been increasing. Greenhouse Gasses are those that help form the invisible barrier between the sun and the earth. This barrier helps block ultra-violet and infrared radiation from the sun as well as keep in heat to warm the earth.

Sources of Greenhouse Gasses

50% Comes From CO2
18% Is Methane (such as Landfill Gases)
12% Is Surface Ozone
6% Is Nitrous Oxides
14% Is Chlorofluourcarbons

Source
Although there are many Greenhouse Gasses such as ozone (O₃), sulfur dioxide SO₂), methane (CH₄), nitrous oxides (NO_x) and chloroflourocarbons (CFC's) the most significant by far is carbon dioxide (CO₂). Although carbon dioxide occurs naturally, and is necessary to maintain life on earth, the steady increase is having an effect on the world's climate and is causing global warming.

Source

In light of being unbiased and giving voice to various viewpoints, another problem with carbon dioxide emissions should be addressed. A lack of emissions, according to Steve Connor, could reduce CO₂levels below the threshold for photosynthesis to occur. This, in turn, could result in Earth's water vapor to escape into space.

The Causes
While there are many sources of Greenhouse Gas emissions the most notable are listed as follows:

Burning Fossil Fuels
(see plots below)
-Transportation
-Industry
-Heating
-Power Generation
Volcanos

Source


Source	Source

Greenhouse gas emissions have increased at the same rate as the overall world economic production, measured by the Gross World Product (GWP - the green dots on the chart). The GWP reflects the increase in worldwide industrialization and human population levels. From this it is obvious that the increase in world population palys an important role in increasing emissions.

What We Are Doing About It

Currently there are a number of ways carbon dioxide is being controlled. Some involve the research and development of alternative sources of energy that does not depend on the burning of hydrocarbons. Others use a socio-economic approach using a "credit trading" system for a carbon dioxide emission allowances. Even storage and disposal of carbon dioxide is being researched and utilized.

Storage and Disposal

There are several processes that can capture carbon dioxide from power plant flue gasses. Some include absorption by liquid solvents, such as mono-ethanolamine (MEA), and others involve adsorption of CO₂ molecules onto a solid. Separation membranes are also used in combination with MEA solvent to enhance the capture process of CO₂ from the exhaust of turbines. One use of captured CO₂ is enhanced oil recovery (EOR), where it is injected into oil wells. Most of the remaining CO2 is trapped in the reservoir.

CO₂ recovery pilot plant tests at Nanko Power Plant Japan. This recovers 2 tons per day of CO₂from the flue gas of a natural gas boiler. (Kansai Electric Power Co., Japan)

Storage of CO2 is an alternative to emissions. Aquifers have potential for storage as does storage devices deep within the ocean.
A CO₂ Penetrator Marine Disposal System is a technology being researched that will store and transport carbon dioxide in containers designed to inject it's payload into the ocean floor.

Another intriguing idea for storage is using a chemical reaction between carbon dioxide and magnesium silicate that makes a stable compound. Natural processes do this already, but over the course of hundreds of years. Researchers at the Los Alamos National Laboratory in New Mexico are discovering ways to make the reaction go to completion in about a half an hour. They have yet to make this operation on an economically feasible scale.

Alternative Energy Sources

Sources of energy that does not involve the combustion of hydrocarbons is an important solution to controlling the amount of CO₂ in the atmosphere. Wave Energy, Tidal Energy, and Hydroelectric Power all tap the potential and kinetic energy produced by the earth and the motion of rivers and oceans. Nuclear Energy is another way to produce large amounts of energy without CO₂ production. Since accidents like Chernobyl have caused doubts by the public in the safety of nuclear power stations, steps have been taken in recent years to prevent accidents on small and large scales. Solar Energy is another clean, renewable resource that is economical and efficient.

"Credit" Trading

The recent Kyoto Covention brought about some ideas to control and reduce carbon dioxide emissions. 'The right to pollute the air then, would be bought and sold through a carbon dioxide emissions market. By allotting a fixed amount of emission permits — and providing credits to those who reduce emissions — economists believe companies would have the incentive to decrease burning of coal, oil and natural gas'(MSNBC.com). Industrial groups could earn forest credits for planting forests to offset carbon dioxide emissions. They could trade forest credits for carbon dioxide emissions.

Links

References Arctic Borderlands Ecological Knowledge Co-op
http://www.taiga.net/coop/indics/grnhsemit.html

CNN Interactive at CNN.com
http://www.cnn.com/EARTH/9710/22/greenhouse.adv/

Fact Sheet on Renewable Energy -- Wind, Solar, Biomass, Geothermal
http://www2.vivid.net/~ses/facts.html

Technical solutions for reducing greenhouse gas emissions
http://www.ieagreen.org.uk/doc3.htm

Based on an item in The Independent by Steve Connor entitled 'Save the planet'
http://www.globalideasbank.org/1993/1993-130.HTML

Stay Cool--Locking up CO2 with magnesium silicate, Popular Science
http://www.popsci.com/content/science/news/980325.s.html

Reducing CO2 emissions: Nuclear Power
http://www.kepco.co.jp/ekankyou/hairyo/1/1-2-3.htm

Environmental Science and Technology, March 1998
http://pubs.acs.org/hotartcl/est/98/mar/kyo.html

"How a Market Could Clear the Skies", MSNBC.com
http://www.msnbc.com/news/125901.asp

Web page Design by T. Akim Nilausen and Nichole Brown Productions, 1998