Phytoremediation Lab Report

INTRODUCTION

Around the world, we observe an increase in the number of contaminated soil, groundwater as well as surface water. These contaminants arise due to human activities that revolve around the industrial and agricultural sector. Some contaminants arise due to military activities as well. If conventional methods were to be used for remediating these contaminants, then the cost that would be added will be too huge. Moreover the potential of these methods is very limited and they can be applied only to small areas.

1.PHYTOREMEDIATION

Phytoremediation refers to the methods and techniques by which living plants are used to clean up the environment which includes the air, soil and water which may be contaminated with

Another basis on which phytoremedition can be classified is the mechanism involved. Such mechanisms include extraction of contaminants from soil or groundwater; concentration of contaminants in plant tissue; degradation of contaminants by various biotic or abiotic processes; volatilization or transpiration of volatile contaminants from plants to the air; immobilization of contaminants in the root zone; hydraulic control of contaminated groundwater (plume control); and control of runoff, erosion, and infiltration by vegetative covers. [5]

Although it is very advantageous in various ways, phytoremediation has its own disadvantages and limits which will be discussed in the next section.

1.2 ADVANTAGES AND DISADVANTAGES

Advantages : o The cost for the technology is much lower than that for the conventional methods o Monitoring of plants is easy o Allows the recovery of metals in the mining industry o Environment friendly, least harmful method since it uses naturally occurring organisms i.e plants

Disadvantages : o Requires long term commitment o Not possible to completely prevent the leaching of the contaminants into the groundwater o The toxicity of the contaminants determine the survivability of the plants grown in the area o Since the plants accumulate the contaminants, there is the possibility that they enter the food

The solution is usually gently aerated but may be un-aerated. If un-aerated, the solution level is kept low enough that enough roots are above the solution so they get adequate oxygen. A hole is cut in the lid of the reservoir for each plant. There can be one to many plants per reservoir. Reservoir size can be increased as plant− size increases. A home made system can be constructed from plastic food containers or glass canning jars with aeration provided by an aquarium pump, aquarium airline tubing and aquarium valves. Clear containers are covered with aluminium foil, butcher paper, black plastic, or other material to exclude light, thus helping to eliminate the formation of algae. The nutrient solution is changed either on a schedule, such as once per week, or when the concentration drops below a certain level as determined with an electrical conductivity meter. Whenever the solution is depleted below a certain level, either water or fresh nutrient solution is