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Treating drinking water is just a drop. Strict environmental rules means that the sewage of entire cities has to be cleaned. Companies are just waiting to plunge in and treat. Till about the

end of 2000, Delhi's sewage treatment plants followed the effluent standard of 20 milligram per litre (mg/l) for biological oxygen demand (BOD) and 30 mg/l for total suspended solids

(TSS). But Yamuna is getting dirtier because of the 4,088 million litre of wastewater it receives daily. Keeping this in mind, the CPCB on January 19, 2001 asked the Delhi Jal Board (DJB) to

follow new norms of 10 mg/l BOD, 15 mg/l TSS and 1,000 most probable number (MPN) per 10 millilitre of total coliform at its new plants. Soon after CPCB gave this order, a debate started

over who can deliver these new standards. Who can clean the muck? The DJB claims only MNCs have the technology to achieve these stringent standards. About a year back, the DJB floated a

tender for its 45 million gallons per day (mgd) Kondli sewage treatment plant. Few companies applied and of them many were rejected. The DJB is yet to decide whom to give the contract.

According to a senior DJB officer, three MNCs -- Austria-based VA Tech Wabag GmbH, France-based Ondeo Degremont and US-based Utility Equipment Management (UEM) Group -- are in the race. But

VA Tech has financial problems and UEM has no experience in running a treatment plant in India. So Degremont is the only choice DJB has. According to government rules, this is a case of

single tender and DJB has to put out a fresh tender again. But will another round help? "No, because we know it will again be a single tender. We did not realise that there is hardly

any company in India which can give results of 10 mg/l BOD and 15 mg/l TSS for sewage treatment. Environmental rules have been made stringent but there aren't many technology

providers," claims the officer. Only us, say MNCs MNCs claim sewage treatment requires the best technology, but most treatment plants in India follow the conventional activated sludge

process. ASP is a technology which uses sedimentation tanks and microorganisms to reduce BOD and TSS in sewage to 40 mg/l and 60 mg/l (see box: _Cleaning the muck_) Degremont, which operates

three sewage treatment plants in Delhi, says it too uses ASP but then follows it up with biofiltration. At the 40-mgd capacity Rithala Phase II plant, sewage is first treated using ASP and

then effluent from the tanks is taken to BIOFOR filters, a patent product of Degremont. It is this biofiltration process which sets it apart from conventional sewage treatment processes.

Biofiltration first traps fine floating materials in the sewage with the help of a screen. After this, the sewage passes through 20 biological filters. The complete process gives an end

result of 15 mg/l BOD and 20 mg/l TSS. The left over sludge is used to produce biogas which generates electricity. "The Rithala plant daily generates 23,000 to 25,000 unit of

power," says manager Sanjay Khadayate. Give us a chance: Indian industry Indian companies aren't impressed. "Degremont is not offering anything extraordinary. They follow the

conventional ASP and then do biofiltration. But we have an advanced technology in which there is no need to go in for biofiltration. We can treat sewage to 10 mg/l BOD at the secondary

treatment stage alone," says Krishnan Rajagopalan, of Thermax Ltd. Yogendra Chaudhury, counsellor, Confederation of Indian Industry, says, "There are some very good Indian

companies like Thermax and Paramount which can give as low BOD as asked for. They have set up plants but face difficulty in working with municipalities." Chaudhary claims that sometimes

rules in tenders keep out Indian companies and then municipalities cry hoarse over lack of competition. Popat gives an example. "The Chennai corporation recently floated tenders for

desalination plants of 100 million litres per day (mld), 200 mld and 300 mld capacity. Only companies, which have set up plants of 15 mld, 30 mld and 45 mld, can apply. The tender asks for a

turnover of Rs 250 crore for a 100 mld plant, Rs 500 crore for a 200 mld plant, and Rs 1,500 for a 300 mld plant. To add to all this, companies have to deposit earnest money of Rs 50 lakh

and Rs 100 lakh. No Indian company can meet these requirements. Only MNCs have that deep pockets to meet these demands." "There are several technologies offered by Indian companies

that can achieve 10 mg/l BOD in sewage. The only issue is initial cost and high power consumption," says Trivedi. A senior DJB officer says Thermax had applied for the Kondli plant but

was disqualified because the company did not have experience. Companies say this is a typical Catch-22 government policy. 'Plants, not stories' Working with

'progressive' municipalities, Ion Exchange and Thermax are setting up model treatment plants. "Ion Exchange is setting up a 12 mld plant for Goa corporation for Rs 4 crore.

The treatment plant is based on advanced cyclic-activated sludge technology, which gives a BOD up to 5 mg/l and removes nutrients from the sewage," says Popat. Ion Exchange is also

talking with the Brihanmumbai Municipal Corporation and Jammu and Kashmir government to set up similar plants. Ion Exchange says it has another technology called C-MEM (submerged membrane

bio-reactor) which uses membranes to treat sewage. The membranes are submerged along with the sewage in a tank which is continuously aerated. The company uses this technology to treat sewage

at its factory in Rabale near Mumbai. "Sewage, which has a BOD and chemical oxygen demand (COD) of 250 mg/l and 550 mg/l, is treated to get a result of less than 5 mg/l BOD and about

30 mg/l COD. The treated sewage looks as good as the drinking water supplied by Maharashtra Industrial Development Corporation," says Nitin Umbralkar, marketing manager of Ion Exchange.

The Rabale plant uses eight membrane modules, with each module costing about Rs 2.5 lakh. Ion Exchange also manufactures INDION, a sewage treatment plant which can be packed in a container

and transported. Thermax Ltd, which is based in Pune, Maharashtra, says it too has the best technology which can function quite efficiently in Indian conditions. "Our company believes

in decentralised treatment of sewage because pumping sewage from one part of the city to another doesn't make sense. It involves huge investment in the conveyance system. That is why we

bid for smaller plants and have already set up a few," says Rajagopalan. Thermax recently set up a sewage treatment plant in Sangvi town near Pune for the Pimpri-Chindwad Municipal

Corporation (PCMC) based on fluidised aerobic bio (FAB) reactor technology. Four years ago, when PCMC floated a tender for 12 mld STP it wanted the conventional ASP technology. But the land

wasn't big enough and people complained that the proposed plant would stink. Thermax won the contract by impressing the corporation with its FAB reactor. "The total cost of the

treatment plant is Rs 5.6 crore but we have designed it in such a way that the running cost is minimum. For instance, we do not need to pump out the sewage. Sewage flows out because of

gravity. If we were to use conventional technology, it would take us at least eight hours to treat sewage. But the FAB reactor enables us to do the job in just 1.45 hours," says

Rajagopalan. The company says it has already set up 72 treatment plants based on FAB reactors.