It can be also defines as any water that has been adversely affected in quality by anthropogenic influence or else being contaminated by organic and inorganic materials ,excessive minerals and heavy metals. Untreated water generally contains the high amount of organic materials, pathogen microorganisms usually bacteria, three main nutrients (nitrogen, phosphorus and potassium), noxious, toxic compound and aesthetically substances. This entails health of humans and is the environmental hazards and must be convey away from it source and carefully controlled by treatment before final disposal. The goal among this is to protect the environment, public and human life in the manner and social – economic concerns as wastewater is the problem. The measure problem of wastewater in Mars can be solid waste and organic materials from toilets (flushing), waste from domestic activities (food preparation) since the living conditions on Mars are not well pleasant, or hospitable for human living in it, people living Mars (colonists) have to live indoors for some important reasons by that way, they are facing a major problem of wastewater being resulted from their uses.
Therefore it is important to provide the alternative solutions to wastewater that could provide the better sustainable living conditions on Mars so that the environment is not damage and resources especial water to make sure that it is not depleted because water is the natural renewable resource that is the humans , animals and plants need. The main aim of treating wastewater is to convert it or make it suitable into effluent that can be either returned or reversed to water cycle (re- usable) with minimal environmental issued. Wastewater treatment is the process of making water to be suitable or up to standard for its applications or transform its back to its natural state. This process is required before water is used and after it has been used to make sure that its quality is maintained. According to Mars, using of water should be carefully controlled and maintained.
Supply of water should be carried out by using water supply systems based on the long term bases. Water supply can use storage and recycling, therefore for this involves the quantity and the quality of water to be provided, planned Mission duration, expected life cycle cost (including costs for the probability of loss of crew) and the required water supply reliability. 3 | P a g e Water supply reliability is an important factor in crew safety, as measured by the probability of loss of crew, it also affect Mission success, as measured by the probability of loss of Mission. The water system developed international space station could be used on Mars but designed for microgravity. Since Mars have partial Earth gravity ,water supply technologies could be used. (Jones, Hodgson, and Kliss, 2014).
If water supplied in the Mars fails than the people living on it will be highly affected in few days of water depletion. Therefore higher reliability is required and water system on Mars requires intrinsic hardware reliability and highly controlled system design. The system need analysing of number of people living in Mars (crew), Mission duration of 18 months, return delay up to 18 months, water consumption , drinking and food preparation water, urine flush and wash water. So in order to ensure the safety of crew on Mars, water system should provide enough water and undergoes the recycling system that is more reliable although this will be costly. 4 | P a g e Body Factors about mars: Mars is the place to the tallest mountain in the solar system Olympus Mons, having largest dust storms which can last for months or even cover the entire planet and it have approximately the same land mass as the Earth. The seasons are extreme because it’s nearly around the Sun compared with other planets.
The Sun appears about half the size as it does to Earth at the closest point to Sun. Therefore this planet is quite different, unfamiliar or unknown environment from other planets. Mars have bad hygiene (contact with harmful microbes that can cause infections and diseases), starvation and it does allow the survival of humans, so people are sent to it to do some research and projects but putting people into it, is risky for their health and safety the one of its which include wastewater. (Jones, 2014) The following diagram highlight simplest water system which can be used in Mars to supply water, maintaining and transforming all used wastewater to potable or safe water for domestic activities on Mars.
As shown in Figure 1, the water system operates in such a way that atmosphere, water and wastewater recycling processers are included. Carbon dioxide is vented to the space or transferred to compressor accumulator and then oxygen is generated and supplied while Carbon dioxide undergoes the reduction and release CH4 in the atmosphere and generate Figure 1: Water system architecture that can be used in Mars to supply and maintain water quality 5 | P a g e hygiene water. All products from atmosphere are transferred to wastewater storage and then processed by water processor which sent it to potable water storage. Resupply water also processed before they can be used. Waste from respiration (urine, flush water) together with other wastewater is combined treated with other solids waste. This system clearly showed that the Mars atmosphere can be directly used as working gas, which helps to reduce the need for transportation of gas suppliers and minimize the fresh water demand by recycling forms of organic or hazardous waste.
Usually water treatment involves technology (wastewater collection pipes and treatment system), science, engineering and business, it is designed to remove solids, bacterial pathogens, plants organic and/inorganic compounds. The following are the treatment strategies which can be used in Mars to secure sustainable living for prolonged missions as it was mentioned earlier, wastewater treatment methods are broadly classified into physical, chemical and biological processes by where water is treated and purified for it maintenance. Processes Treatments Methods Physical unit operations Primary ? Screening ? Flotation ? Sedimentation ? Settling ? Filtration Chemical units operations Tertiary ? chemical precipitation ? adsorption ? disinfection ? de-chlorination Biological units operations Secondary ? activated sludge ? aerated lagoon ? trickling filters ? pond stabilisation ? anaerobic digestion ? extended aeration Table 1: Different processes with their corresponding treatments and methods used in treatment of wastewater 6 | P a g e Based on the above table, the physical processes are usually used in the primary treatment for removal of insoluble particulate, Chemical used in tertiary treatment for removal of inorganic nutrients and biological processes are used in secondary treatment of the wastewater for biological removal of dissolved organic matter, and also can be used in tertiary treatment for biological removal of inorganic nutrients Application of treatment methods The waste management system on spacecraft or space station does not operate in isolation. It is integrated into other systems associated with the environmental control and life support. On Space Station, the waste is treated as far as possible. This is relatively easy with air, water and clothing, but garbage and sewage pose more of a problem.
Both are potentially an infection hazard. (Jones, 2012). Air on the Space station needs to be circulated all the time, and this is achieved by the air recirculation system. In this system, dust and microbe particles are removed by drawing through the filters which are cleaned from time to time. Carbon dioxide is removed and replaced by oxygen.
Gases and vapours that are not normally present in the pure air are removed. This become industrial processes like cooking, the crew and many other sources. As far as the of the crew are concerned, removal of microbial particles is very important. The filters are efficient enough that bacteria, fungal spores and even viruses are removed from the circulation. Sampling of air is carried out regularly. Any garbage that contains food or any other damp organic compounds has been rotting from the moment it became cool enough to eat.
Bacteria have been munching their way through it, micro-fungi and moulds have been dissolving it and spreading their unpleasant juices poon it. It is possible that creatures like insects and worms have been excreting on it and laying their eggs on it, all this biological activity has their biological effects. Gases and unpleasant odours are produced. The life-forms in it are multiplying at an alarming rate and overall, the garbage is becoming a health hazard. In the right conditions, all this can occur within hours of disposal.
How can we look after our trash in space for six months or more between garbage collections? 7 | P a g e Bagging and sealing may be an answer, but gases may pose problems, as completely sealing the bag may cause the bag to burst because of build-up of gas pressure. In addition, biological action of the type that occurs in garbage can produce heat, this heat can be so great that it will spontaneously combust-catch fire. This can happen on the farm to hayricks under same conditions, where damp hay, microbes and anaerobic conditions conspire together to create higher temperatures. The similar condition is also possible to happen in garbage.
On Space Station 2020, a minimum of rotting garbage is produced. Disposable food containers are always washed, dried and then disposed to ultraviolet before being bagged as inactive garbage. Active garbage, which emits gas is placed on a container that allows gases to event into the air conditioning system, where there are neutralized. Other garbage containers include wet containers that take wet chemicals or bio-hazardous materials from the laboratories which cannot be reprocessed through the waste water system. Wastewater treatment In waste water treatment plants, the unit operations and processes described in the previous sections are grouped together in a variety of configurations to produce different levels of treatment, commonly referred to as preliminary, primary, secondary and tertiary or advanced treatment. 1.
Preliminary treatment Preliminary treatment prepares wastewater effluent for further treatment by reducing or eliminating unfavourable wastewater characteristics that might otherwise impede operation or excessively increase maintenance of downstream process and equipment. This characteristic includes large solids and rags, abrasive grit, odours and in certain cases unacceptably high peak hydraulic or organic loadings. Preliminary treatment process consists of physical unit operations namely, screening and comminution for the removal of debris and rags. Grit removal for the elimination of coarse suspended matter, and flotation for the removal of oil and grease.
Other preliminary treatment operations include flow equalization, septage handling and odour control methods. 2. Primary treatment Primary treatment involves the partial removal of suspended solids and organic matter from the wastewater by means of physical operations such as screening and sedimentation. Pre- 8 | P a g e aeration or mechanical flocculation with chemical additions can be used to enhance primary treatment.
Primary treatment act as a precursor for secondary treatment. It is aimed mainly at producing a liquid effluent suitable for downstream biological treatment and separating out solids as a sludge that can be conveniently and economically treated before ultimate disposal. The effluent from primary treatment contains a good deal of organic matter and is characterized by high biological oxygen demand (BOD). 3.
Secondary treatment The purpose of secondary treatment is to remove the soluble and colloidal organics and suspended solids that have escaped the primary treatment. This is typically done through biological processes, namely, treatment by activated sludge, fixed-film reactors, or lagoon systems and sedimentation. 4. Tertiary/ advanced wastewater treatment Tertiary treatment goes beyond the level of conventional secondary treatment to remove significant amounts of nitrogen, phosphorus, heavy metals, biodegradable organics, bacteria and viruses.
in addition to biological nutrient removal processes, unit operations frequently used for these purposes include chemical coagulation, flocculation and sedimentation, followed by filtration and activated carbon. Less frequently used processes include ion exchange and reverse osmosis for specific ion removal or for dissolved solid reduction. Sewage treatment Sewage is screened to remove large solid chunks, which are disposed in landfill site. It flows over to the settlement tank to let the fine particles to settle, the settlement is called the activated sludge.
The supernatant is then percolating filtered and/or aerated. The water can be filtered again, and then disinfected (chlorinated in most cases). When there is no other complication, the water is returned to nature back to ecological cycle. The sludge removed from the settlement is composed of living biological material. A portion of it may be returned to the aeration tank, but the raw sludge is digested by both microorganisms.
Anaerobic (without oxygen) and aerobic (with oxygen) bacteria digestions are used. At the digestion state, carbon dioxide, ammonia and methane gases are evolved. Volume of the digested sludge is reduced, and it is acceptable as a fertilizer supplement in farming. 9 | P a g e Treatment by activated carbon is mostly due to adsorption and absorption. When a chemical species is adhered to the surface of the solid, it is an adsorption. When partial chemicals bonds are formed between adsorbed species or when the absorption got into the channels of the solids, it is called absorption.
Municipality wastewater effluent may contain a number of microorganisms of toxic elements, some as heavy elements or metals because under practical conditions wastes from all many small or large and even informal industries are directly discharged into the common sewer system. These amounts are called trace elements, some removed during treatment while others persist and cause harm on the living environment. This is what cause harm on our planet and increase health issues worldwide without people knowing the cause. Sometimes, water can be treated with wastewater treatment plant and one may think that they are done, water is clean while there are some surviving organisms that are toxic to the environment and water users. (Jones, 2013) Those reckless treatment plants are penalised and sometimes suspended to prolong the planet’s life. For prolonged life of a planet and its people, the wastewater treatment is needed in order to secure safe water to be used especially during the draught period of the year.
Although this is a major importance in the planet, there are concerns of the safeness and sustainable living conditions that are monitored. Firstly, the effluent that is obtained during the cleaning process should be useful to the environment, like agricultural use by farmers while making sure it does not affect the living of the people and organisms in the environment. These effluents are sometimes composted and sold for good use. When water is being cleaned by the water plant it produces lot of useful microorganisms that can be used in laboratory and testing of water constituent.
When sludge is activated during the cleaning process, all the microbes or organisms are collected in one side of the plant, where they are collected and using known characteristics they are tested and identified to be sold. Wastewater treatment plants can clean up to millions of litres per day of working and that means more organisms are collected in each day of cleaning. For microbes, all the treatment plant is suited in isolated places from the living environments, where no one will easily get infected by smell in wastes. Good hygiene is maintained for people working on the plant system are always highly recommended to prolong their lives including the surroundings or visitors 10 | P a g e Conclusion The world’s freshwater resources are under strain.
Reuse of wastewater, in concert with other water conservation strategies can help lessen anthropogenic stresses arising from over- extraction and pollution of receiving waters. On the other hand, are concomitant environmental risks with water reuse such as, pollution and salinization of groundwater and surface-water, degradation of soil quality and impacts on plant growth, the transmission of disease via the consumption of wastewater-irrigated vegetables, and even increased greenhouse gas emissions associated with pumping large volumes of wastewater to an irrigation district. The significance of such risks will plainly be dependent on the reuse scheme at hand. Ultimately, the challenge facing wastewater reuse is to minimize such risks so as to maximise the environmental gain.
