New Possibilities in ETP Sludge Handling and Disposal Methods

New Possibilities in ETP Sludge Handling and Disposal Methods

By Umesh Kulkari

Cost of sludge treatment and disposal is about half of the total cost of wastewater and sludge treatment and disposal cost. Hence it needs expert attention.

Only few years ago, dewatering ETP sludges to below 20% dry solids content seemed to be impossible. But with the recent advancements, it is possible to get solids as dry as 35 to 40% dry solids.

ETP sludge in any form is hazardous. The hazard is probably proportional to the square of the water content it has at the outlet point. Type of the industry producing the sludge is also very important in deciding the hazard. For example, bio sludge produced from pharma, pesticide and fertilizer industrial segment is far hazardous than municipal bio sludge. Water content in the sludge depends primarily on nature of sludge itself. It also depends upon the practices and equipments used for the purpose. Sludge, broadly is classified as biological or chemical. With the rapid industrialisation the classification ceases to be so simple. Further with global warming outcry becoming shriller by every passing day, it becomes even more important to have a holistic approach.

Many of the pollution issues, which may seem insurmountable, can in fact be solved with will, holistic and focused approach.

Changing the process, using alternative biodegradable chemicals, waste minimisation audits, etc., are some of the tools to ultimately bring about a qualitative difference in the pollution scenario. However my focus through this article is ETP sludge dewatering. I will cover dewatering techniques and final disposal methodologies including incineration.

The main objectives of sludge dewatering are:

• To avoid human contact with the sludge to the maximum possible extent
• To produce sludge suitable for disposal
• For easier sludge handling
• To reduce trucking cost
• To reduce incineration cost where applicable
• To reduce cost of bulking agent in composting where applicable
• To reduce leachate production at land fill site
• To reduce litigation costs
• To carry out these processes without causing nuisance or offence

Following are some of techniques used for sludge dewatering

• Sludge drying beds
• Filter presses
• Centrifuges
• Vacuum filters, and
• Belt filters

http://www.ipfonline.com/IPFCONTENT/articles/new-possibilities-in-etp-sludge-handling-and-disposal-methods.php

Soon, you'll be able to surf the web at the speed of light!

Tue, Mar 2 04:45 PM

Washington, March 2 (ANI): Scientists from the Massachusetts Institute of Technology (MIT) have created a new infrared laser made from germanium that operates at room temperature, which has made light-speed computing come one step closer to reality.

The research removes the cryogenic cooling systems previously needed for infrared lasers and could lead to powerful computer chips that operate at the speed of light.

"Using a germanium laser as a light source, you could communicate at very high data rates at very low power," said Jurgen Michel of the Massachusetts Institute of Technology, who developed the new germanium laser.

"Eventually, you could have the computing power of today's supercomputers inside a laptop," he said.

The creation of a new laser, even one based on germanium, is not newsworthy; more than 15,000 different lasers, some of which use germanium, have been created since the 1950s.

What makes this particular germanium laser unique is that it creates an infrared beam at room temperature.

Until now infrared germanium lasers required expensive cryogenic cooling systems to operate. The new germanium laser operates at room temperature.

To create the germanium laser, the scientists take a six-inch, silvery-gray disk of silicon and spray it with a thin film of germanium.

These same disks are actually used to produce chips in today's computers.

An electrically powered, room-temperature, infrared laser for laptop computers is still years away, however, cautioned Michel.

If and when those laptops do arrive, they will be powerful - more powerful in fact than even today's supercomputers.

The battery that powers the laptop won't necessarily last any longer, but the power it does hold will make calculations orders of magnitude faster than today.

"We need high-density, low-power solutions," said Kock.

Computer chips are constantly getting smaller and smaller, but they are approaching the fundamental limits of electron-based computing.

Light-based computing is one option to improve the speed and power of computers.

"Germanium-based optical computing is an especially attractive material for optical computing because it wouldn't require any change to the existing computer chip industry," Kock said.

The same machines that use silicon could also use germanium to make future chips. (ANI)

source "http://in.news.yahoo.com/139/20100302/981/tsc-soon-you-ll-be-able-to-surf-the-web.html

two giants of the social networking ...facebook & twitter

It is no longer news - or even worth discussing - why Facebook has more than 400 million users and why 140 - character Twitter updates are the single most important influence today on the media, on the entertainment economy and perhaps even on human knowledge.

What is important to note, however, is that these two giants of the social networking and microblogging world, are becoming more pervasive in the smallest things we do online.