The Treatment of Wastewater with Microalgae Essay

Fresh cell homogenate of G. semen collected from Lake Jelino (“FH” treatments) with chl-a range: 894 – 3576 mg m-3, caused distinct negative effect on Daphnia survival (Fig. 2.). It increased with the increasing biomass of alga and time of exposure. At lower chl-a concentrations (894 and 1778 mg m-3) the survival rate averaged 40% – 70 % after 24 h and 20 % – 30 % after 48 and 72 h of exposure. However, the addition of the most concentrated and fresh G.semen homogenized biomass (chl-a: 3576 mg m-3) caused 100% Daphnia mortality already after

Toxic algal blooms are occasions of excess reproduction of toxin-producing algae, making damage to the ecosystems and humans. Among the toxic algal blooms are ones caused by Pseudo-nitzschia species, producing a toxin called domoic acid (DA) (Tatters, Fu & Hutchins, 2012). These microalgae belong to diatoms and are spread within the Northwestern Atlantic region, causing sporadic issues in the Gulf of Maine (Fernandes et al., 2013), Chesapeake Bay and along the west coast since 2006 (Pistocchi et al., 2012).

Back to the history, the eutrophication problem was first time concerned by public on Great lakes at the 1960s, the Lake Erie was covered by algae as a result of over dumped phosphorus from the sewage and other waste water, at that time, the Lake Erie was known as the “Dead Sea of North America”(Fitzpatrick, J. J., and Di Toro 1999). The reason cause this problem can be concluded in 2 points, 1. the stresses of overfishing, 2. development of phosphorus-based detergents. At the end of 1960, the Canada and the United States have realized the penetrance of this problem and finally sit on the table to sign an agreement that limiting phosphorus dumps to the Lake Erie, and plan to control existing unstoppable algal growth. Because of the awareness of Canada and US government, the concentration of phosphorus got a significant success. And this problem happened again during the 1990s, but this time the reason why this happen is more complexly.

The experiment took place in a laboratory setting, and the first step was obtaining sixty individual Daphnia magna (that were neither adults nor tiny offspring) from a large tank in the lab. These individuals were equally divided into three groups; low density, medium density, and high density. The twenty Daphnia assigned to the low density group were split into four groups of five and pipetted into one of four tubes filled with 10mL of Chlamydomonas algae. The twenty Daphnia assigned to the medium density group were split into two groups of ten and placed into one of two tubes also filled up to 10mL with Chlamydomonas. The final twenty Daphnia were all placed into a single tube filled with 10mL of the algae. In order to avoid suffocation-related

Nitrate reduction may be beneficial to a microorganism because it allows bacteria to continue undergoing respiration even in the absence of oxygen as the final electron acceptor. By using nitrate as the electron acceptor, some bacteria can undergo anaerobic respiration, which is more preferable than fermentation because respiration produces more ATP compared to

(9.) Smith, J. M., Casciotti, K. L., Chavez, F. P., & Francis, C. A. (2014). Differential contributions of archaeal ammonia oxidizer ecotypes to nitrification in coastal surface waters. ISME Journal: Multidisciplinary Journal Of Microbial Ecology, 8(8), 1704.

The purpose of this experiment is to understand the effects of nutrient enrichment and eutrophication, using samples of water from Rio Salado and Encanto Park. The samples will contain different concentration levels of nitrogen, phosphorous and nitrogen and phosphorous combined and the impact it has on algae growth. The results recorded showed that the nitrogen concentration levels had a little change, phosphorous levels had a higher change and phosphorous and nitrogen combined had a significantly higher change, resulting in higher algae growth. The results showed that phosphorous indeed is a limiting nutrient in algae growth, but to achieve the highest growth rate, both nitrogen and phosphorous need to be combined.

The algae used for the algal balls in this investigation were Chlamydomonas Reinhardti. The algae balls were made and stored a week before the experiment, data collection and data analysis. During the experiment the algae balls were placed in indicator solution then exposed to a light source. Algae was used to determine the rate of carbon dioxide (CO2) absorption, whereby a highly acidic orange hydrogen carbonate indicator indicated the rate of photosynthesis as it is sensitive to pH changes and CO2. As CO2 concentration increases, the pH decreases (basic/alkaline) and indicator solution becomes a purple colour.

“Harmful algal blooms are overgrowths of algae in water. Some produce dangerous toxins in fresh or marine water but even nontoxic blooms hurt the environment and local economies.” (Environmental Protection Agency). Algal blooms can be comprised of two different organisms, green algae and cyanobacteria. Green algae are eukaryotic organisms that contain chlorophyll and photosynthetic; whereas, cyanobacteria are prokaryotic organisms and classify as bacteria. They also lack a true nucleus, do not contain chlorophyll, but do obtain energy through photosynthesis. (Carolina Beyond the Tape 12) In addition, runoff containing phosphates and nitrates, water moving very slowly, and sunlight all contribute to the growth of algae blooms which is not a good thing. People and animals can be negatively affected by the dangerous substances found in algae blooms; this can cause people and animals to become sick and they could possibly die. When more water to be cleaned because of the toxins found in the water it can become very expensive. To add on, if a town or state’s main freshwater source is drastically affected by an algae bloom they can potentially lose the place that they depend on for clean water, and have to find a new one. Additionally, there are different ways for algae blooms to be harmful to an environment. For instance, algae blooms deplete the amount of oxygen in the water and

The experiment consisted of two trials, each composed of 16 separate environments, four for the control, four for .01 mole of fertilizer, four for .1 mole of fertilizer, and four for 1 mole of fertilizer. Each contained equal parts chlorella solution and distilled water, and were exposed to equal amounts of sunlight. Once every two days, measurements were taken with probes for temperature, conductivity, and dissolved oxygen, and with a colorimeter for absorbance. Dissolved oxygen levels best indicated the health of the algae, and led us the conclusion that fertilizer can permanently harm the environment in and around the place of

Photosynthesis is a two stage process by which plants, as well as some protists and bacteria, reduce carbon dioxide and oxidize water to convert sunlight into chemical energy, producing oxygen as a byproduct. For photosynthesis to be properly carried out by an organism, it must find itself in the proper environmental conditions with careful consideration of the pH. Research has proven that the optimal pH for the many algae organisms is between 7.0 to 10.0 (Coleman & Colman, 1981). As a strong base, NaOH is often used to adjust the pH in order to reach the optimal value based on the amount of free CO2 (Pedersen et. al. 2013).

I open the double doors, put on my lab coat, and goggles, holding my notebook between my knees. Heading over to my lab bench, I slip on some nitrile gloves and begin labeling tubes. Holding my tubes, I open the door into the growth room, where I take eight flasks off the shaker box. I look inside the flasks; they look dark green and dense. They are growing well. Thus begins my day at an algal biofuel lab. As an intern at Los Alamos National Laboratory in New Mexico, I head over to the lab after school. Specifically, as a member of a project working to facilitate the transition from petroleum-based fuels to algal biofuels, I mainly focus on adapting algae to a wide range of salt concentrations for our industrial partner, a petroleum company,

The urea cycle plays an important role in diatom metabolism, serving as a distribution and recycling center for inorganic carbon and nitrogen. This cycle is an essential biological process in diatoms, contributing to diatom’s nutrients in order to compensate for the lack of important macronutrients that could increase their growth level within increasing the metabolism process (Allen,

Excessive supply of nutrients tend to cause overgrowth phytoplankton and algae. This results to death of other organisms (fish, crustaceans, molluscs, etc.), slow growth rates of fishes and other organisms (Morris, et al., 1989), decrease net photosynthesis of attached algae (Schindler, 1988) and death of the aquatic ecosystem. All of which are caused by the high production of algal toxins and excessive respiration.

The disposal of untreated wastewater coming from the industries into the water bodies will pollute the water bodies because of its high concentrations. So, the wastewater produced from the industry should be treated properly to meet the permissible limits given by central and state pollution control boards. Therefore it is necessary to treat the wastewater properly with the help of an appropriate treatment plant. However, the treatment plant even though properly planned may not work satisfactory because of several reasons. Hence, it is essential to evaluate the treatment plant considering individual treatment unit in the entire treatment flow. In the present work emphasis has been given to the study of the performance of treatment facilities because of its importance in the conventional treatment of wastewater. Hence, the literature review related to the evaluation of the entire treatment process along with biological treatment process particularly suspended growth process Activated Sludge Process (ASP), attached growth process Trickling Filter (TF) and a combination of the both suspended and attached growth process Hybrid Reactor (HR) is presented in the following sections of this chapter.