Technology

Water is life, essential for daily sustenance and healthy living. With plummeting groundwater levels, contamination of water sources and increasing consumption, challenges in the water sector have increased manifold. Safe, sustainable and affordable water in the face of growing water needs is a severe challenge. With fresh water supplies already hard pressed to meet growing demand, technology plays an important role in managing and using the limited available water in a cost effective and critical manner.

Water contamination occurs both due to human activities and natural processes. Depending upon the purpose for which the water is needed--municipal, industrial or agriculture--treatment is carried out. The technology used will depend upon the current water quality, future standards required and economics of the treatment method. Water treatment removes contaminants that may be biological, physical or chemical in nature. 

Various water treatment technologies are present that purify polluted water by removing undesirable chemicals or biological contaminants and making it fit for human consumption. Use based classification of surface waters in India has been laid down by the Central Pollution Control Board (CPCB). The details of the permissible and desirable limits of various parameters in drinking water as per Bureau of Indian Standards (BIS) standard specifications for potable water are also detailed in the IS 10500:1991

Water treatment plants use technologies to produce water that is safe both chemically and biologically, and that is appealing in terms of colour, odour and taste. The control point for water quality determination must be the consumer's tap and not the treatment facility, which means that the water quality must not be impaired during transmission, storage and distribution to the user. The treatment methods at the plant include aeration, coagulation and flocculation, sedimentation, filtration and disinfection.  Some of the prevalent water purification & treatment technologies are listed below.

  • Capacitive Deionization (CDI) is a technology where ions are removed from water by passing it through a spacer channel with porous electrodes on each side
  • Ozonation is a chemical water treatment technique based on the infusion of ozone into water
  • Ultraviolet technology uses Ultraviolet light, just like sunlight, to kill micro-organisms present in the water
  • Reverse Osmosis (RO) is a technology that removes a large majority of contaminants by pushing the water under pressure through a semi-permeable membrane
  • TERAFIL is a burnt red clay porous media used for filtration & treatment of raw water into clean drinking water, developed Council of Scientific & Industrial Research (CSIR), Bhubaneshwar 
  • OS- Community scale Arsenic Filter is an organic arsenic filter, developed by IIT Kharagpur
  • Filtration methods that may include rapid/ slow sand filters remove dirt, rust, silt, dust and other particulate matter from water
  • Solar water purification systems 

Water treatment technologies for safe, potable water in rural areas that includes Capacitive Deionization Technology (CDI) using carbon aerogel, solar operated groundwater treatment plants and electro chlorination are described in a booklet ‘Compendium of innovative technologies on rural drinking water & sanitation’ by the Ministry of Drinking Water and Sanitation. 

Domestic drinking water filtration methods vary depending upon the method of purification used, the degree of ‘purity’ required, and the type of contaminants in the water. No one technology will fulfil all criteria--there is no ‘silver bullet’ solution. Some of the more popular methods for Household Water Treatment & Safe Storage (HWTS) options includes boiling, SODIS (Solar disinfection), Chlorine Tablets, Liquid Chlorine (online, Biosand filters, Flocculent treatment, Ceramic candle, Filter combinations, Pureit filters, Ultra Violet (UV) filters, Reverse Osmosis (RO) and Ion Exchange (IEX).

For more on water purification systems, click here.

Domestic Greywater Recycling Water filtration technologies

Any used water, other than sewage from toilet basins that exit a house or apartment complex, is referred to as sullage or greywater. This is mostly made up of water used in bathrooms and kitchens, constituting the bulk--nearly 60%-70%--of the total volume of water used in a day. 

Before underground sewerage was introduced in most cities, water followed a cyclical route. Water was drawn from dug wells within the premises. Refuse water from the bathrooms and kitchen was let out into the garden while water from the closets reached septic tanks. The soil treated the greywater and sent it back into the ground, thereby closing the household water consumption-reuse loop.

Contrary to popular belief, greywater is largely free from pathogens. As it is mostly made up of easily degradable organic waste and chemicals from cleaning products, it can be purified and reused in-situ with minimal effort. In many homes and apartment complexes, sending this perfectly reusable resource out of the plot along with sewage common-sight. Greywater can be brought back into the water cycle by employing simple biological and mechanical filtration techniques.

There are two basic requirements apart from the necessary plumbing arrangements for treating domestic wastewater:

  1. Open soil space
  2. Water loving plants

Water from bathrooms and kitchens can be diverted through a dedicated pipeline into the plant bed set aside for the treatment process. Here, the nutrients present in the waste water are absorbed by water loving plants such as Canna or Cyperus while the soil bacteria polish off the organic waste from the water. 

  • Constructed wetlands – These wetlands are created to replicate the process of bio-filtration that occurs in a natural setting. Here, the water is purified using two media, the planted surface and the gravel bed underneath. 
  • Reed bed treatment plants – A smaller version of the constructed wetlands, reed beds are perfect for individual houses and smaller complexes.
  • Mechanical filtration – Mechanical systems such as sand filters and pebble flow systems can be used to help filter out waste from the water by separating the discernable solids from the liquid component. 
  • Lava filters – These pebble filters are a combination of both biological and mechanical systems where the stones act as support structures for microorganisms that help break down the waste. 

For more on the basics of rainwater harvesting and greywater recycling, refer Self reliance in water: A book by Indukanth Ragade.  

Sewage treatment--Municipal and Industrial

Waste water flowing out of urinals and toilet closets are referred to as ‘blackwater’ or sewage. Blackwater cannot be treated in the same way as greywater as the former contains a heavy pathogen load from the fecal matter suspended in it. Sewage from towns and cities flowing directly into water bodies is one of the major reasons for water pollution.

Municipal wastewater treatment plant, Yelahanka, Bangalore

While City Corporations are in charge of laying underground sewerage pipes to collect, channel and treat sewage, localities outside city limits have a greater responsibility of managing their own waste. Apartment complexes and townships mostly rely on small scale sewage treatment plants (STP) to treat their waste.

Wastewater can be treated either in the presence or absence of oxygen. While aerobic digestion involves the breakdown of waste by microorganisms in the presence of oxygen, anaerobic systems work in its absence. Various types of processes are used to treat both domestic and industrial waste water such as:

  • Activated Sludge Process where biological agents such as bacteria are used in the presence of air to oxidise the nutrients present in the sewage 
  • Sequencing Batch Reactors help equalize, aerate and sediment waste water in timed batches by mixing it with activated sludge and oxygen to reduce the organic load 
  • Membrane Bio Reactors provide a higher degree of organic and solid removal by combining the principles of both mechanical filtration and biological digestion to treat municipal waste 
  • Moving Bed Bioreactors are mainly used for aerating and treating high-strength wastewater where several floating polyethylene bio-films move in suspension provide surface area for the nutrient-digesting bacteria to grow 
  • Trickling filters are low-cost, aerobic systems made up of a fixed bed of gravel, rocks and moss over through sewage is passed to remove the nutrient material in the suspension 
  • Facultative aerated lagoons are shallow ponds where the sewage is allowed to with the atmospheric oxygen in the upper layers while the sludge settles down at the bottom 
  • Waste stabilisation ponds, categorized into three broad types – anaerobic, facultative and aeobic depending on the oxygen use intensity – help in reducing nutrient content and polishing waste water to re-use quality 
  • Up-flow anaerobic sludge blanket digestion treats wastewater in the absence of oxygen where the feed enters the tank through the bottom and flows upward as the bacteria present in the sludge digest organic the matter 

The CPCB publication on the status of sewage treatment in India throws light on the performance of sewage treatment plants across the country and the technologies currently being used in them. The status of waste water generation and treatment across the country is also available on the ENVIS Centre on hygiene, sanitation, sewage treatment systems and technology. 

  • I have one acre farmland which is slopey in the Aravali Hills. I want to conserve the rainwater using check dams. Request your advice on how to you do it ?
    Anonymous (not verified)posted 6 months 2 days agoread more
  • Dead rat in the water tank collecting rainwater through which water went into open well. We have removed the rat, but can see all its hair might have gotten into the open well, I suppose. Please advise on purifying the well water and cleaning the tank so that I can use it for future.
    Anonymous (not verified)posted 6 months 2 days agoread more
  • Hi Team, This is Adithya from Hyderabad city Moula Ali area. I have an independent house situated at Moula Ali, Jawahar Nagar colony. We dug a borewell in the year 2005 with 300 ft depth, after that we flushed it in the year 2011 and then we never had a water problem. However, from past one year we...
    Anonymous (not verified)posted 6 months 2 days agoread more
  • Myself Arunodoy Sarmah. I am working as officer with a psu bank in Assam. I would like to enquire about a small water treatment plant at my home in Guwahati. During winter months we face water shortage issues here in Shantipur hillside area in Guwahati even though we are hardly 5 km from Brahmaputra...
    Anonymous (not verified)posted 6 months 3 days agoread more
  • Bihar and northeast India reel under floods As the water level of the Brahmaputra River rose above the danger level across Assam, 30 of the 33 districts in the state were deluged by floods, affecting nearly 43 lakh people and claiming 15 lives. In Bihar, incessant rains in neighbouring Nepal ca...
    swatiposted 6 months 4 days agoread more
  • Meghalaya's draft water policy gets approval To address conservation and protection of water sources in the state, the Meghalaya cabinet has approved a draft water policy for the state. The policy was drafted by the state water resources department in consultation with experts in wate...
    swatiposted 6 months 4 days agoread more
  • Hi, My name is Govind and we drilled borewell 480 feets deep and we got water at 2.5 inches. Now we have to install the motor, which motor we need to install? Also, in our area low voltage problem is there please kindly help me.
    Anonymous (not verified)posted 6 months 5 days agoread more
  • Can I use failed borewell hole for rainwater harvesting which is at 110ft, at my home?
    Anonymous (not verified)posted 6 months 5 days agoread more
  • Hi Sir, I have a 200 feet borewell. Water level at 20 feet. I need help to select motor for my borewell. Which is best submersible motor or compressor motor?
    Anonymous (not verified)posted 6 months 5 days agoread more
  • Hello, We are in the process of flushing our community borewells that have dropped in yield. The vendor tells us that there is a low cost compressor flushing with 2-3 kg pressure and a high cost flushing where the rig goes in and flushes the borewell with 20 kg plus pressure. He recommends the high...
    Anonymous (not verified)posted 6 months 1 week agoread more
  • I have a borewell of depth 700 feet in my agriculture land in Malappuram district, Kerala, with a single phase electricity connection. Kindly advise me on the most appropriate motor that I need to install for irrigation purposes.
    Anonymous (not verified)posted 6 months 1 week agoread more
  • How one can stop digging of borewell in neighbourhood which is being dug illegally?
    Anonymous (not verified)posted 6 months 1 week agoread more
  • Chikkaballapur is a district in the state of Karnataka, just north of the capital Bengaluru. A peri-urban area that was once an agricultural centre for this region, today Chikkaballapur is facing a unique problem.  Decreasing rainfall has meant increasing periods of drought for this area, wh...
    priyadposted 6 months 1 week agoread more
  • 3 phase 20hp motor running at 1000ft and the voltage shows as 360-380v at 11am and the motor runs for 24 hrs everyday. The water output has reduced significantly and the mcb is 63A 415V. Not able to figure out the problem why the water bill is coming up to 1,65000 to 1,80000. Varies monthly, but in ...
    Anonymous (not verified)posted 6 months 1 week agoread more
  • Nirmala Sitharaman, Finance Minister alluded to gaon, garib and kisan as the centre of all policies of this government, while announcing a clutch of schemes aimed at the rural and urban poor. Her budget speech last week reiterated the government's commitment to ensuring piped water supply to al...
    Amita Bhaduriposted 6 months 1 week agoread more
  • Government cuts budget for Jal Shakti Ministry by 9.4 percent; increases funds for rural drinking water mission  In the 2019 Budget, the Centre reduced the allocation for the water ministry from Rs 8,860 crore in 2018-19 to Rs 8,245 crore for the Department of Water Resources, River Devel...
    swatiposted 6 months 1 week agoread more
  • India not a water defict country. Neglect and lack of monitoring behind country's water scarcity: CWC As per the report, Reassessment of water availability in India using space inputs, by the Central Water Commission (CWC) with technical support of the National Remote Sensing Centre (NRSC), Hyderab...
    swatiposted 6 months 1 week agoread more
  • What will be the recharge rate of a borewell of 150 mm and 300 mm diameter, respectively in the district of Patiala, Punjab for the purpose of rainwater harvesting. The borewell ends about 15 meter before the first aquifer and hence sends the water into a layer of sand. The borewell will have perfor...
    Anonymous (not verified)posted 6 months 1 week agoread more
  • Hello, I'm from Nashik (Maharashtra). I drilled a borewell 9 yrs ago. It's about 150 feet deep. Now 15 feet depth is filled by sand exactly below motor and I can't get water from well. Please suggest me any solution to remove sand from borewell.
    Anonymous (not verified)posted 6 months 1 week agoread more
  • Hi, We have a capacity of one lac ltr of STP installed in the building. The STP is working in good condition, but we are facing an issue. The output of STP is one lac ltr per day but the usage of the same can be done in 2 areas, i.e. flushing and gardening. 40,000 ltr is used in the above areas. Whe...
    Anonymous (not verified)posted 6 months 1 week agoread more

Pages

Spatial and temporal information of agriculture, forest, topography, land use change, climate and socio-economic factors are very useful in the planning and implementation of Natural Resource Management (NRM) programs. Despite this relevance, quantitative information on these variables is not widely known at ground level due to unavailability of quality data and mapping techniques.

October 10, 2019 10:00AM - October 14, 2019 6:00PM
October 5, 2019 12:00PM

Topics

Sub-Categories

Regions

Why clear water reservoir is having only 15 years of design period? Source: CPHEEO

Topics

Sub-Categories

Regions

A new technology developed by Indian scientists is helping in revival of mangroves degraded due to rising sea levels, climate change and human intrusion in the Sunderbans in West Bengal.

New Delhi, September 17 (India Science Wire): A new technology developed by Indian scientists for ecological restoration is helping in revival of mangroves degraded due to rising sea levels, climate change and human intrusion in the Sunderbans in West Bengal. 

Topics

Sub-Categories

Regions

Policy matters this week

NGT orders DDA to ensure farming on the Yamuna floodplains is stopped by 2020

Topics

Sub-Categories

Regions

News this week

Telangana government, tribals stand against proposed uranium mining in Nallamala forests

Topics

Sub-Categories

Regions

We have 235 feet borewell at home and we use texmo compression motor to pump. We observed that the water is not pumped up to the water tank from past few days. We could see meagre water in tank even if motor is running for more than an hour. We already had a borewell with 90ft depth and since there was no water, we installed new one last year with a depth of 235ft after checking with experts. We did not face any issues till date and the electrician has checked the motor and confirmed no issues with it.

Topics

Sub-Categories

Regions

Floating 'islands' give new lease of life to a lake in Indore

Choked by sewage and effluent discharge, lakes in and around Indore are in a terrible state and in need of restoration. A bustling city in central India, Indore was declared the cleanest city in India three years in a row. After cleaning the streets and its garbage landfill area, it has now turned its attention towards cleaning as well as restoring its lakes and ponds.

Attachments

Topics

Sub-Categories

Regions

Hello,

Topics

Sub-Categories

Regions

While farm ponds in Jharkhand have helped farmers increase yields, they have also exposed them to the risk of price fluctuations, highlighting the need for ‘beyond the farm’ interventions.

While enhanced irrigation coverage has been hailed as an important way to improve agricultural productivity, it continues to lag behind in India and agriculture continues to be rainfed, subject to the vagaries of the monsoon. High groundwater dependence for irrigation has not only led to its depletion and quality deterioration, but has also raised questions about its sustainability in the long run.

Attachments

Topics

Sub-Categories

Regions

I have a borewell depth of 650 ft and I have fixed a 3hp 40 stage single phase Texmo pump, because of the silt the pump run only once and its not running now. What should I do now to pump the water. Is there any way to use the same pump by doing any process or should I go for compressor pump. If yes, then of what capacity?

Topics

Sub-Categories

Regions

Pages

Subscribe to RSS - Technology