Why Greywater Management System Is Needed

Water is the primary need of any living creature on the planet. With the growing population and urbanization, the availability of the consumable water is diminishing. The growth of the economy or the population cannot be controlled. But with change in sensitivity towards the consumption of water, we can meet the present demands and optimum use of the same can help to save our future generations.

The quality and the quantity of the available water is depleting due to population and pollution which is driving the governments to set the laws for conservation of the water resources and greywater management system is one of the significant methods to achieve the same.

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Greywater is the reclaimed water that has been used once in domestic, commercial or industrial activities and can be reutilized after treating up to standard limits for certain tasks.

This greywater can be treated through various technologies depending on the nature of reuse for further applications like car washing, irrigation, toilet flushing or street cleaning.

The current Indian scenario

The current Indian scenario

Water is becoming a rare resource in the world. In India, it has been projected by International water management institute that by 2025, one third of the population will live in complete water scarcity.

With the rapid increase in the population and demand for fresh water the available resources are depleting day by day. The per capita surface water, which was available at 2300 m3 (6.3 m3/day) in 1991 has depleted to 1980 m3 (5.7 m3/day) in 2001 and is projected to deplete to 1191 m3 by 2050. And the water requirement is projected to 1450 Km3 in 2050 as compared to 1086 Km3 presently. Hence, it is very crucial to reduce the use of surface and groundwater in all sectors, find alternatives to fresh water reuse option for optimization of the available water. The alternatives include rainwater harvesting and greywater management system and reutilization for meeting the projected deficit.

GREYWATER

The wastewater is generated from various activities like washing, laundry, bathing, mopping, flushing, cooking, etc. This water is categorized into three types depending upon the level of contaminants present in the source. They are black water, dark grey water and light grey water. Black water is generated from the flush and are high in disease causing microorganisms. Dark grey water is the water  that originates from the kitchen sink, which also contains disease causing germs and organic contaminant from food waste and grease or oils. Light-greywater is originated from bathroom sink, tubs, showers and laundry. This water also contains disease causing microorganisms but in lower number as compared to the other two types. The level of organic contaminants is also less in this type of water. The figure shows how much water is discharged as wastewater in regular household activities.

Benefits of greywater reuse

  • The first and the foremost reason of greywater management and reuse is to replace or conserve the freshwater for other potable uses.
  • The greywater is rich in nutrients like phosphorus and nitrogen that are present in detergents, which are good for the plants. The water generated from laundry if used appropriately can help in good vegetation and plant growth.
  • Reduces the cost incurred in sewage treatment. Greywater when treated and used within the area minimises the wastage through sewer lines and cost incurred in its treatment at sewer cleaning facilities.
  • Usually the reutilization of the greywater require no or minimal treatment before use.
  • Greywater can help to supply most of the water needs for irrigation purposes.

These various methods can be used to treat the same from low level of complexities for basic uses like gardening or flushing to high level of treatments to remove sediments, oil and grease, chemicals, odour and other impurities depending upon the nature of reuse.

How is Water Recycling an answer to our water crisis?

how-is-water-recycling-an-answer-to-our-water-crisis

Today water recycling is considered the key to our water crisis. With great breakthroughs in all the areas of science, we have come to a conclusion that only self sustaining and holistic solutions are the way to go forward for a secure future. One of the areas that has been focused globally over the past few years is Water Management which stresses on Waste Water Treatment and Water Recycling. Water Management is essential for our survival as we have a limited supply of potable water on the planet and with deforestation, the rate of replenishment of this resource has deteriorated disastrously over the past decades. Everywhere around the world, waste water treatment for water recycling is stressed upon each day. This not only eases efficient water management but also provides a way for decentralization of the resource. Decentralization is essential for sustainability as it distributes the resource and its management along with its total stock amongst the community. This results in equal and viable distribution all over the community making them self reliant and helps in managing the resource at the community’s level. This paves a way for sustainability. When we talk about water recycling and waste water management, even that can and should be carried out at every level by the community. Over the years technology has had various developments to effectively implement Water Recycling by using Waste Water Treatment or Sewage Treatment Plants.

Earlier these plants were limited to industrial applications, however they have gained popularity amongst the public to be used in residential complexes for water recycling and have various benefits such as:

  • 1) Since the treated water can be used for purposes which do not require potable water, such as irrigation, landscaping, washing etc, Waste water treatment plants help in managing the water supply.
  • With reuse of water, the water consumption can be decreased which results in reducing the water costs.
  • Treated Grey water is full of nutrients and hence very much beneficial to the vegetation and environment.
  • With water recycling we are essentially reducing our carbon footprint and giving back to the nature and our ecosystem.

Although most of the Waste Water Treatment Plants have been developed to treat waste water into reusable grey water, with time many projects have come up that use water recycling indirectly for potable purposes. These plants consist of recharging groundwater aquifers and augmenting surface water reservoirs with recycled water.These are often called Groundwater recharge projects. In such projects recycled water is injected or spread into the groundwater  aquifers to augment groundwater supplies.

Water Recycling Process

Water Recycling Process uses physical, biological and chemical principles to decontaminate water and make it fit for reuse. It consists of three levels of treatments: Primary Treatment, Secondary Treatment and Tertiary Treatment.

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Primary Treatment

Simple mechanical and physical processes are implemented in Primary treatment which removes approximately half of the contaminants from wastewater.

Bar screens: At the beginning of the water recycling process, the raw sewage is passed through a system of mechanical bar screens which removes large solids such as sticks, rags, and plastic material from the wastewater stream.  A horizontal rake on a toothed gear drive removes the captured material out of the chamber for removal to a sanitary landfill.

Grit chamber: The wastewater flows through an aerated grit chamber and where the stream is saturated with very fine air bubbles which encourage settling of the fine grit particles.

Primary clarification: At this point the flow velocity of the wastewater is slowed to encourage solids settling. Biosolids are digested and used for purposes like conditioning the soil or composting.

Secondary Treatment

Biological processes are used in the Secondary treatment which removes most of the remaining contaminants.

Aeration Basins: Oxygen is mixed into the water as it flows through an aeration basin. Here, bacterial microorganisms remove the organic material and convert non-settleable solids to settleable solids which are later captured in final clarifiers.

Final Clarifiers: Most of the solid materials gets thickened and settles out into the final clarifiers but some are returned to the aeration tank to reintroduce incoming water with microorganisms.

Tertiary Treatment

Tertiary Treatment is the additional purification or advanced treatment of the water. Once the water reaches this level, water is passed through sand before undergoing chemical disinfection in chlorine contact chambers, which kills any remaining microorganisms and the chlorine is removed using sulfur dioxide. Today we are standing at the crossroads of our future. With water recycling, we can reuse the water supply and manage our water resources effectively. How we handle the crisis today, will determine what our future generations will have to face in order to survive.

Why maintaining Sewage Treatment Plants in condominium is difficult?

Maintaining Sewage Treatment Plants In Condominium

Sewage Treatment Plants seem like the answer to many water related concerns today. They help us re-utilise and manage water supply efficiently. But this system also comes with its own set of challenges. Most of these challenges are faced after installation of these plants. Some of these challenges are:

1. Power Consumption

The greatest expense while running a Sewage Treatment Plant is the power consumption. It requires more and more power with increasing sewage volume. Also, to keep the process going and maintain the plant properly, there must be a constant supply of power. This makes it difficult for the condominium to manage. To ease the burden of this high consumption, solar panels can be installed along with the Sewage Treatment Plant so that it has its own power or less power consuming technologies can be used in the plant for various processes such as  membrane technology for the aeration process.

2. Staff

The staff required to effectively manage and maintain a Sewage Treatment Plant must be properly trained and certified for the same. They need to be on board 24/7 for the maintenance of the plant. This again becomes difficult as there are not much resources equipped with such certification and trainings. To overcome this issue, automation processes can be used in the treatment plant which cut down almost 30% of the running costs in long run but they too need operational supervision to run smoothly.

3. Sludge

Sludge is a thick viscous, mud like material produced during sewage treatment. Sludge may contain the toxic waste from the sewage treatment plant, and can be hazardous if not treated properly. Hence it becomes a delicate environmental challenge for wastewater treatment to safely dispose of excess sludge produced. The recycling of sludge which contains many useful organic matter and nutrients in agricultural applications is considered as the best solution.

4. Secondary Costs

Activated sludge treatment comes with its own various challenges, one of the major challenge being the resources required. Plants that treat activated sludge are not only costly to build but also costly to maintain. Primary and Secondary processes of sludge treatment requires vast tracts of land for large and costly settling tanks and aeration basins. To solve this issue, Advanced technologies using smaller process basins by increasing the amount of biomass per unit volume can be used.

These are just a few challenges in maintaining Sewage Treatment Plants. For any queries about STPs and how to manage them effectively, contact us on +(91)-8130999055 /+(91)-9810858062 or visit our website http://www.sanicon.in/

How to convert your landscape into a waste water treatment plant?

How to Convert your Landscape into a Waste Water Treatment Plant

Landscapes provide a calming and serene touch to any space. Landscape architecture can be defined as the skill of incorporating the man-made structures, like buildings, with the natural landscape and planting. Landscape Architecture’s gaining more and more popularity amongst the masses as Landscape architects apply artistic and scientific principles to the planning, design, management, preservation, and rehabilitation of natural and built environments.

Current landscape maintenance practices often have harmful impacts on the environment. Native woodlands and other natural habitats are cleared for urban growth and subsequently vast lawns and manicured arrangements with exoic ornamental plants are planted. These types of landscapes require extensive mechanical equipment, large quantities of water, fossil fuels, pesticides and fertilizers. This places a heavy toll on the ecosystem, pollutes ground waters and causes more frequent destructive flooding.

Essential components of landscaping

Lawns: Lawns are the most basic yet most important component of a landscape design. They act as a unifying factor for any landscape design. Lawns bind together all other components of the landscape such as walkways, garden, ornaments, ponds or patios etc.

Plants and trees: The plants and trees are chosen keeping in mind the climatic conditions of the areas. Trees or plants can be chosen for their ornamental value, ground cover, water usage etc. Combination of trees and plants based on these factors creates a visually appealing scene characterized by contrast, proportion, scale and balance.

Walkway: Including walkways into the landscape designs adds architectural details to the design. Since they are completely man-made features of any landscape design, there is a certain room for creativity for the architect to bring the essence of the building’s architecture into the landscape.

Water-bodies: Water-bodies such as waterfalls, bridges, fountains, ponds can be included in the landscape designs. Such structures not only provide serenic beauty but are also beneficial for the sustenance of the ecosystem.

Passive sewage treatment plants

Passive wastewater treatment is a type of Onsite Sewage Treatment and Disposal Systems that excludes the use of aerator pumps, includes no more than one effluent dosing pump with mechanical and moving parts, and uses a reactive media to assist in nitrogen removal. Passive sewage treatment plants do not require the ongoing addition of chemical reagents to conduct treatment. As a result these systems:

  • Have low running and maintenance costs
  • Are long-term treatment options
  • Require minimal supervision

They are ideally implemented for the treatment of water with low acid, pollutant and suspended particle loads.

Passive sewage treatment plants

Essential components if passive sewage treatment plant.

  1. Anaerobic treatment

Anaerobic treatment

Anaerobic digestion is a biological process in which microorganisms break down biodegradable matter in absence of oxygen. Anaerobic digestion or treatment produces primarily methane and carbon dioxide which can be converted into electrical or thermal energy. Anaerobic treatments for wastewater are generally implemented when treating wastewater with high concentration of biodegradable organic material. The anaerobic treatment of wastewater converts organic material into biogas (70% methane and 30% Carbon dioxide) via hydrolysis and acidification.

  1. Removal of Nitrates and Potash

The process of biologically removing nitrogen is known as denitrification. Denitrification requires that nitrogen be first converted to nitrate. The nitrified water is then exposed to an environment without free oxygen. Organisms in this anoxic system use the nitrate as an electron acceptor and release nitrogen in the form of nitrogen gas or nitrogen oxides. A readily biodegradable carbon source is also needed for efficient denitrification processes to occur. Nitrified process water flows into the anoxic reactor and is then combined with a supplemental carbon source, typically a dilute methanol solution.

Removal of Nitrates and Potash

The removal of phosphorous from wastewater involves the incorporation of phosphate into TSS and the subsequent removal from these solids. Phosphorous can be incorporated into either biological solids (e.g. microorganisms) or chemical precipitates. Chemical precipitation is used to remove the inorganic forms of phosphate by the addition of a coagulant and a mixing of wastewater and coagulant. The multivalent metal ions most commonly used are calcium, aluminium and iron.

  1. Aerobic Treatments

Aerobic treatment systems use forced air to treat wastewater and surface application or drip irrigation to disperse the treated wastewater. Aerobic treatment systems consist of: a trash tank, an aeration chamber, a disinfection chamber and surface or drip dispersal fields. These components are used to treat, disinfect, and disperse the treated wastewater.

Passive sewage treatment plants (1)

Converting your landscape into a Sewage or Wastewater Treatment Plant

  1. The  walkways can be designed in such a way so as to incorporate anaerobic treatment chambers.
  2. Since removing nitrates and potash from the wastewater is a very vital part of the wastewater treatment process, planters can be planted in the gravel bed. Here the water flows post anaerobic treatment. In case of space constraint, hydroponics could be used.
  3. To add aerobic treatment systems, water bodies such as fountains, waterfalls, ponds can be used. Here also hydroponics system can be implemented if the area is limited.

With sustainable water management gaining focus, converting landscapes into Wastewater Treatment Plants not only aides in the re-utilization of greywater but also boosts the ecosystem. The recycled and mineral enriched greywater leads to greener spaces and reduces the water costs for landscape maintenance at the same time.

BTC opts for treated water

BTC opts for treated water

A commendable work carried out by Bangalore Turf Club for keeping the gardens lush green even at the time of water crisis. They have used treated water from the sewage treatment plant. While they are aiming at rainwater harvesting the best use of greywater is taken up. 

Credits: http://timesofindia.indiatimes.com/city/bengaluru/BTC-opts-for-treated-water/articleshow/52243790.cms

7 Undeniable safety rules for greywater utilization

In my last post, we have discussed greywater and how it can be used. Here extending that topic to further explore the importance of greywater treatment

We all know that the water once used in bathroom sinks, laundry or shower heads is considered as grey water and it contains organic material that is good for plants.

Why do we use grey water:

The use of this water has gained its importance due to two main factor:

1: Reducing the need of freshwater when the activity does not demand it. As we all know that the fresh water is scarce and is a topic of consideration in the world. The minimal use of the same can help us to put a step together in controlling the situation.

2: Eliminate waste: This water if not reused will be passed through drains which when comes in contact with filth, garbage and trash becomes unusable and lead to the wastage of water. Greywater management can help to eliminate this wastage.

How the greywater is treated:

The water is collected in a septic tank which is first treated for further use. Usually, the following steps are carried out in the process:

Removal of solid waste: The first step is to remove the solid waste like hair, food particles, lint etc.

Removal of chemicals: The chemicals of soap, pathogens, and other microbes is removed from the water before it is used further.

Uses of greywater:

The water once treated can be used in following ways:

Big garden:

Use Grey Water in gardening after treatment

Use Grey Water in gardening after treatment

The most common and best use is to water the big gardens where we need a good quantity of water. This can be done by connecting a diverter directly from the source to the garden. This is best in the case of ornamental plants or trees.

For edible plants: Once treated thoroughly, it can be used to water the fruit and vegetable plants

Drought regions: In drought prone areas the greywater management served as a boom. The water is used at the maximum to eliminate the wastage and save for the need.

No garden: As already described in the previous post, it can be used for flushing  or for Hydroponics after treatment, where kitchen vegetables could be grown.

Safety rules:

There are certain rules to be followed for using the greywater safely:

Do not use untreated grey water in garden for vegetable plants

1: Untreated water should not be used on fruit or vegetable plants

2: When it is passed in garden, should not cross the boundary to reach others premises

3: It should not be kept untreated for long as the microbes and pathogens will multiply to dangerous levels.

4: If you are using bleach or hard chemicals in laundry, do not use the grey water.

Underground Pipe for Grey Water in garden

Underground Pipe for Grey Water in garden

5: Keep the pipes or drains underground to keep the animals and children coming in contact with it

6: Do not use if you are suffering from stomach infection

Label Grey Water In Use

Label Grey Water In Use

7: Keep the pipes and taps of greywater labelled to avoid misuse.