Saturday, December 4, 2010

Wadi Hanifa Bioremediation Project, Riyadh.



Bio-remediation Facility

Objectives

The Bio-remediation Facility is designed as habitat and natural structures to support the

biology that will do the work of cleaning the water.

The three main goals of bio-remediation are:

1. Reduction of fecal and total Coliform bacteria to safe levels;

2. Elimination of bad odours; and

3. Prevent cumulative negative impacts of nutrient load through the Wadi.

the bio-remediation Facility is the integral part of the Wadi hanifah restoration project. the main treatment process of the water comprises 3 main functions that will take place in this area:

1. Aeration to kill the coloform bacteria in the water;

2. Development of a food chain to bio-accumulate excessive nutrients derived from urban sewage and wastewater; and

3. De-nitrifying (to metabolize nitrogenous compounds) to reduce odours emanating from the wastewater.

The four components of the Bioremediation Facility are designed to enhance the natural treatment process are:

1. biocells – These are the basic units of the Bio-remediation Facility which are responsible for the bulk of nutrient assimilation. The whole facility consists of 3 biocell groups as follows: Group 2 (20 biocells), Group 3 (34 biocells) and Group 4 (80 biocells);

2. aeration system – This provides sufficient levels of dissolved oxygen (DO) to the system killing coliform bacteria and creating favorable conditions to microbes, fish & other aquatic

organisms;

3. artificial periphtyon benthic substrates – Provide substrates for biofilm / periphyton which is essential for bio-accumulating nutrients through the food chain; and

4. Fish (tilapia) – Serving as the top of the food chain and controlling the growth of filamentous algae.

The Bioremediation Sampling Monitoring Program is designed to allow for water sample collection at strategic locations. The data collected is used to determine the treatment efficiency of individual biocells, groups of cells and of the entire facility. There are twenty two (22) water quality parameters being analyzed in each location and grouped under four principal categories: General Variables; Organics; Nutrients; and Microbiology.

The long term purpose in collecting and analyzing data is to compare system performance to the Master Plan design objectives, in addition to developing long term bio-remediation operation and maintenance protocols.

A summary of water quality analyses is presented in the Nelson Environmental

“Bioremediation and Surface Water Monitoring Report” dated February, 2010.

Bio-remediation Facility performance

Based upon early testing and analyses – only five (5) months of data sets from August 2009

to February, 2010 – Nelson Environmental reported conclusive data in several key areas:

Suspended solid removal rates are high (clear water).

Ammonia removal rates are high.

Fecal and total coliform removal rates are significant.

System is functioning without odours from the water.

Aquatic higher life forms (fish) are thriving in the Bio-remediation Facility.

Emergance of a new level of preditors - birds.

In summary, the Bio-remediation Facility is performing beyond expectations.

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