Wednesday, October 17, 2012

Chlorine Safety Concerns Put Sodium Hypochlorite on Spot

In its most recent study, Intratec Solutions LLC (www.intratec.us), a Houston publisher and chemical process consulting firm, scrutinizes industrial sodium hypochlorite production through the chlorination of caustic soda by chlorine gas.  A plant integrated upstream with a chlor-alkali facility and capable of producing 250 kta of bleach would present an internal rate of return of 25%.


Sodium hypochlorite (NaClO) is the active constituent in chlorine bleach, a strong oxidizer and bleaching agent.  It has been widely used since the 1930s because of its excellent disinfecting characteristic.  Nowadays, bleach is used mainly in water treatment and laundry bleaching.
The report explains that transport and handling safety concerns are leading to the substitution of chlorine-based water treatment, which represents a significant market expansion potential. Additionally, increased consumption and shortage of fresh water resources will help to increase bleach importance.
According to an AWWA (American Water Works Association) survey, from 1978 to 2008, a reduction of near 30% in chlorine usage in water treatment plants occurred.  From those, about 80% started buying sodium hypochlorite.
In this report, both the capital investment and the operating costs for plants erected on the US Gulf Coast, in Germany and in Brazil are presented.  Included in the analysis is an overview of the technology and economics of a widely used process, similar to the employed by Solvay Chemicals, for example.  The CAPEX for a plant on the US Gulf Coast reaches USD 33 million.

Tuesday, October 16, 2012

40 patients evacuated from Sunderland Royal Hospital after ammonia leak


AROUND 40 patients and staff were evacuated from a hospital ward after an ammonia leak.
Firefighters were called to Sunderland Royal Hospital, Kayll Road, in Sunderland, at around 4.50am today after the ammonia was released.
Around 10ml of ammonia had leaked from a fridge in a drugs room on a ward on the sixth floor of the hospital.
The ward was evacuated. The drugs room was sealed and the fridge was disconnected by firefighters wearing gas-tight suits and it was placed in an over-sized protective drum.
The drum was then taken out of the hospital to safety. It was taken to a protective compound and was rinsed down by fire crews.
Firefighters spent around 40 minutes clearing ammonia gas from the ward, caused by the leak, before the patients were led back into the ward.
Source: http://www.journallive.co.uk/north-east-news/breaking-news/2012/10/16/40-patients-evacuated-from-sunderland-royal-hospital-after-ammonia-leak-72703-32042304/#ixzz29TOEMspk

No chlorine in water samples collected in four towns


While several deaths caused by waterborne amoeba have been reported in the city, a quality report released on Monday said that all 58 samples of drinking water collected in four towns were ‘non-chlorinated’.
A senior official of the Karachi Metropolitan Corporation said that all the 58 samples — 30 from Baldia Town, 10 from Saddar, eight from Lyari and 10 from Bin Qasim Town — collected from main water lines of the Karachi Water and Sewerage Board on Monday had been found unsatisfactory or with no level of chlorine.Also on Monday, the KWSB collected 81 water samples from 13 towns. Of the 81 samples, four — all collected from Gulberg Town — were termed unsatisfactory due to an absolute absence of chlorine in them.
According to laboratory details, 41 samples had traces, while the presence of chlorine ranging from 0.15 parts per million to 2ppm was confirmed in the remaining 36 samples.
The provincial health department was not satisfied with the results related to piped water chlorination and wanted the KWSB to improve its process of disinfecting water, a source said, adding that Health Minister Dr Sagheer Ahmed clearly said that he did not accept results of the samples showing just traces of chlorine as any quality or chlorinated water.


Monday, October 15, 2012

ATIs Model Q45H/85


How to Remove Chlorine from Water at Home


Since water is an essential part of your everyday life, you might wonder how to remove chlorine from water at home.  You want the water that you drink to be safe and clean.  It would be wonderful if all tap water were truly safe, but it does sometimes contain both chemicals and impurities.  Chlorine is added to tap water to kill off harmful bacteria.  Unfortunately, chlorine, even in the relatively small amounts used in tap water, can be unhealthy to consume.  One solution to this problem is buying bottled water, but that can get expensive and it isn’t good for the environment.  Here are some ways to remove chlorine from water at home.
Boil it. Boiling water before drinking it or cooking with it will remove the chlorine from it.  Boil the water for 3-5 minutes.  During that time, the chlorine will boil off making the water that is left behind safer for drinking.  This process can be both inexpensive and a bit tedious.
Use water filters. There are many different brands of pitchers available on the market that have built in filters.  These activated charcoal filters remove chlorine and other impurities from your drinking water.  Some of these filters can be kind of expensive to replace, though they are still often cheaper over time than buying bottled water, and they are better for the environment.
Install a water treatment system. Better yet, install a water ionizer with treatment capabilities that include filtration and chlorine removal. Although the upfront cost of installing a water ionizer treatment system is greater than using the boiling method, or buying a water pitcher with a filter in it, over time this option can be very cost efficient.  Not only do you get the benefits of removing the impurities and chemicals like chlorine from your water, you also end up with alkaline water which has many health benefits and uses that you won’t get from tap or water that has only been filtered.
Use Immediately. Chlorine is added to water to make it safer to store and transport. Once the chlorine has been removed, the water should be used as soon as possible. Having water that’s ready to use immediately is another good reason to install your own water treatment system. There’s no waiting for the water to seep through a pitcher filter or to boil then cool down enough to drink.
No matter which method you choose, you can be certain that your drinking water is safer because you chose to do something to reduce impurities and chemicals before consuming.

Source http://vollarajournal.com/2011/06/how-to-remove-chlorine-from-water-at-home/


Cities And Towns Still Struggle To Control Sewage 40 Years After The Clean Water Act

When a fire breaks out, Fire Chief Scott McGowan is on the call. He’s on the spot when a sewer line breaks and somebody has to fix it. He is in charge of the drinking water plant that serves the 420 people in the small Eastern Washington town.

And he doubles as the wastewater treatment operator, not as glamorous as being fire chief, but it’s part of his job description.

McGowan’s backup at the wastewater plant? Until the city can hire another worker, that would be Mayor Paul Gilliland. He already handles most of the wastewater plant’s paperwork and is studying to earn an operator certification so he can be a full-service mayor.
Harrington is just one of many communities across the Pacific Northwest that is operating on a tight budget and trying not to violate it’s wastewater pollution permit.
One of the main goals of the 1972 Clean Water Act was to stop “point-source pollution.” That’s the sewage and industrial waste pumped out of pipes and into the nation’s waterways.
To help communities build and upgrade wastewater collection and treatment systems in the years after the Clean Water Act’s passage, the federal government handed out billions of dollars in grants. But most of those federal grants are gone, replaced by loans. At the same time, those federally subsidized municipal wastewater systems have aged.
When wastewater treatment plants fail, the environment takes the hit, and so do the people who want to use public waters for drinking water, food or recreation.
These days, local governments’ budgets won’t cover the improvements needed to control pollution discharges. Many are coping with:
  • Aging sewer lines
  • Aging or under-capacity wastewater treatment plants
  • Proper plant operation and maintenance
  • New water quality regulations
  • A lack of financial resources
State and federal records show that Washington’s 223 cities racked up more than 1,500 pollution discharge violations in the past two years. Idaho’s 124 cities tallied more than 1,700 in the past three years. Comparable data are not readily available for Oregon, but its 49 largest cities had at least 150 discharge violations during the past three years.

Big city issues

Over the past several decades, metro areas like Portland and Seattle have spent billions of dollars trying to get their sewage under control. Many of their problems have been linked to combined sewer overflows, or CSOs.
The overflows are a function of sewers built decades ago to carry both sewage and stormwater. When heavy rains fall, the sudden surge of water can overpower the system and send raw sewage directly into the surface water. That worked well until about the 1950s, when people decided it wasn’t a good idea to send raw sewage into their rivers and streams.
Fixing CSOs has been an expensive undertaking.
Last year, Portland finished its state-mandated $1.4 billion Big Pipe Project, installing giant underground tunnels that can carry much larger volumes of sewage and stormwater to the city’s wastewater treatment plants.
That doesn’t mean Portland is trouble free. Sometimes clogged sewer pipes cause overflows, too. Oregon’s Department of Environmental Quality fined Portland $450,000 in 2005 for allowing almost 2 billion gallons of raw sewage to flow into those waters over a five-year period.
Washington’s King County also has been improving its sewage treatment systems and combined sewer overflows, or CSOs. It spent about $2 billion recently to build the Brightwater wastewater treatment plant, which discharges into the Puget Sound.
The county also has built several treatment plants that handle stormwater. One of them, the Elliott West treatment facility, had some violations, including discharging too much fecal coliform and chlorine — both bad for fish and other aquatic life.
The county is working with Washington’s Department of Ecology to find ways to adjust the system, Elardo said.
Big cities must handle and control more pollution than small communities, but they also have more financial options to build and upgrade their infrastructure.
These towns are required to upgrade their facilities to meet new Clean Water Act requirements. But most have few options to pay those costs, other than big rate increases, Pedersen said.

Several towns, one river

Along Oregon’s South Umpqua River, several towns have been working to meet new regulations on nutrients, such as phosphorus and nitrogen. Excess nutrients lead to algae blooms that use up the dissolved oxygen fish and other aquatic life need to live. Some algae also produce toxins that can harm humans and wildlife if they are ingested.
Riddle and Winston are upgrading their plants. Myrtle Creek and Roseburg have finished their upgrades. Glendale and Canyonville are planning to follow suit.
Roseburg had to look for a creative way to deal with its phosphorus discharge because the cost to upgrade its wastewater treatment plant was estimated at up to $80 million, said Gasik.
Instead of sending its treated wastewater to the river, it began to apply it to land. That took care of the large algae mat that used to be in the river outside Roseburg’s treatment plant, he said.
All the upgrades should have an impact on the South Umpqua River, where water quality varies from very poor to poor.
“In the South Umpqua it will make a big difference. That’s one of the, probably one of the few streams left that the point sources are really impacting the water body,” Gasik said.
Not every community needs to upgrade its wastewater treatment plant. Violations can be the result of poor operation or inadequate maintenance.

Poor plant operations

Those have been the problems for the Confederated Tribes of Warm Springs, in Eastern Oregon, said Chae Park with the U.S. Environmental Protection Agency.
The tribes operates two wastewater treatment plants that together they have violated their permits 99 times in the last three years. One plant serves the town community of Warm Springs and the other the Kah-Nee-Tah resort. The two plants discharge into streams that provide spawning and rearing habitat for salmon, steelhead, trout and Pacific lamprey. People use those waters for kayaking, fishing and swimming.
Records show the plants have had violations for total suspended solids, e-coli andbiological oxygen demand, or BOD, which lowers the amount of oxygen available for fish and other aquatic life.
“In terms of their effect on the environment, I think there is definitely potential for adverse effects. For example, suspended solids are going to affect the fish. It may clog their gills. And certainly e-coli, that’s a pathogen. That could come in contact with recreational users, swimmers for example,” Park said.
Park says the tribes haves hired a new wastewater operator and more workers to help maintain the plants.
The Warm Springs Tribes did not respond to numerous requests for an interview.

Side effects of economic development

The town of Burley, Idaho’s pursuit of new businesses led to its wastewater treatment problems. When the city of 10,000 people couldn’t keep its old plant in compliance, officials knew they had to replace it.
Most residents supported putting in a new plant, said Mark Mitton, the city’s administrator.
So in 1998, the city began the engineering for the projects. It also issued bonds and raised sewer fees from $3.26 per household to $27.50.
It took about nine years to complete the plant, which came online in 2007. By then, the sewer rates had reached $45.50 per household.
“Was it hard on people with fixed incomes? Absolutely,” Mitton said.
But there’s another wastewater treatment plant in Burley’s story.
In 2003, the town inherited a second plant from the J.R. Simplot Co. and began using it to lure new businesses and jobs to the area. That worked. Two milk-processing companies, Gossner Foods and High Desert Milk, have been piping their wastes to the industrial plant. And Gem State Processing, which makes dehydrated potato flakes, also set up business in Burley. The state gave the city a $499,000 block grant to help add infrastructure for Gem State Processing. That included wastewater hookup.
The industrial treatment plant, however, is old and wasn’t built to handle milk waste, said Mary Lou Herbert, the supervisor for both plants. It couldn’t meet the pollution limits of its permit.
To make matters worse, parts of the plant had fallen into disrepair. Water has punched a hole in a wall that is supposed to separate two parts of the system. That has upset the balance of microbes that eat the waste, Herbert said.
The city tried to fix the problem by piping some of the industrial waste to the residential plant. But that backfired, causing both plants to violate their permits and sending too much pollution into the Snake River, which is important to the community for recreation and tourism.
“I get frustrated because I was always raised to meet compliance, and I’ve never been faced with these issues before,” Herbert said. “I mean occasionally anyone can have a whoops because something happened. But ours have been over and above normal.”
Now the town needs to borrow up to $6 million to upgrade the industrial plant, administrator Mitton said.
“It has been a good thing for us, and just like any infrastructure, we’ve got to make an investment in it to bring it back into compliance and mover forward,” Mitton said.

Infiltration and inflows

Several small towns in Eastern Washington have been dealing with a mix of problems and some have been violating their discharge permits.
Some of the towns, including Albion, Ione and St. John, have old wastewater treatment plants. All three towns also are dealing with sewer infiltration and inflow, known as I&I in the wastewater world.
Infiltration occurs when sewer pipes have cracks or holes or their joints have failed, allowing stormwater and groundwater to enter the system. Inflow is surface water entering the system through manhole covers, downspouts or by other routes. The extra water can overwhelm and disrupt the treatment plant.
The town has had trouble keeping that position filled and some of its violations are related to operator turnover, Washington said.

Financial burdens

The Eastern Washington town of Harrington, where the fire chief is the wastewater treatment plant operator, had to go in debt to build a new plant. The 420-resident town took out loans and still owes $1.5 million, Mayor Paul Gilliland said.
The new plant, which was completed in 2005, has not been trouble free. Breakdowns have led to violations and expenses. And it has operating costs, too, that have driven the monthly sewer fee rate to $65 per household. That’s $25 more than Seattle charges and $5 more than Portland.
Many other communities have received low-interest rate loans, some that originate with state agencies but that are partially bank-rolled by the federal government.
At one time, communities could fund building or improving their wastewater treatment plants with grants they didn’t have to repay. But in 1987, Congress changed the federal grant program to a loan program administered, in most cases, by states. The states add some money and charge interest on the loans to capitalize their programs, called Clean Water State Revolving Funds.
Some state and federal agencies continue to offer limited numbers of grants, but they don’t come close to meeting the needs of communities in the Pacific Northwest.
In 2012, the federal government gave states $1.5 billion to use in their loan programs. Oregon’s share was about $16 million, Watters said. The interest rate is 2.5 percent.
Tough economic times, however, can discourage borrowing. Local government bodies like city councils may be hesitant to accept a loan if it means raising sewer rates. Sewer rates become particularly dicey during election years.
In Oregon, officials accept applications for its loans three times a year, but during the last two application cycles not one Oregon city or town applied, Watters said.
The lack of borrowing isn’t a reflection of the wastewater treatment needs.
Every four years states ask communities to report how much money it would take to put their wastewater treatment systems in good working order so they could meet the terms of their pollution permits. They report their findings to Congress.
The latest survey, conducted in 2008, shows that it would take at least $10 billion dollars to meet the wastewater treatment needs in Oregon, Washington and Idaho.
Regulators know those figures are understated because many communities don’t report their needs. Simply filling out the paperwork for the survey can be a financial burden, especially for small communities. The rules require communities to document their needs with reports, which can include hiring an engineer to study their facilities.

Federal level realities

The federal government recognized the problems small communities were having meeting their wastewater pollution permits long ago. In 1992, the U.S. General Accounting Office reviewed the outcomes of making the federal grant program a revolving loan program. The GAO report concluded that the loan program:
  • “will not generate nearly enough funds to close the tremendous gap between wastewater treatment needs and available resources.”
  • will pose particular problems for small communities, many of whom cannot repay loans at any interest rate and have difficulty competing with larger communities for loans.
In 2009, the U.S. Environmental Protection Agency estimated the gap between future needs and current spending on wastewater infrastructure of $150 billion to $400 billion for the entire country. The same year, the American Society of Civil Engineers gave the nation a “D-“ for its wastewater infrastructure.
Congress has considered other funding solutions since then, including setting up aClean Water Trust Fund.
Most recently, U.S. Rep. Earl Blumenauer, D-Ore., introduced a legislation that would create that kind of fund.The Bill, calls for taxes on water-based beverages, water-disposal soaps and toilet tissue, cooking oil, toothpaste, prescription drugs –- lots of products that end up in sewer and wastewater treatment plants.
No one really knows how much it would cost to stop pollution from wastewater and sewage systems. But regulators do know it is still a problem that will require funding and finding less expensive, more innovative ways to manage the sewage flushed from homes and businesses every day.










Monday, October 8, 2012

542 Gas Analyzers for Monitoring Nuclear Reactor Coolant Removal


Introduction

The task of decommissioning of nuclear reactors is not just a matter of safe dealing with radioactivity issues, it is equally challenging to remove non-nuclear contamination economically and safely. NNC is presently developing a system for removal of alkaline metal coolant contamination from the Dounreay Fast Breeder Reactor (DFR) that has been kept carefully under maintenance since its shutdown in 1977.

Methods of Decommissioning Nuclear Reactors

As potassium and sodium are both air and water sensitive, the mixture of potassium and sodium metal in alloy form does not just have a high level of radionuclides but also poses a fire risk. This potassium-sodium mixture is used as a coolant. One way of decommissioning nuclear reactors is to drain the bulk NaK from the reactor and deal with the remaining residues using the Water Vapour Nitrogen (WVN) process.
The coolant residues that remain after draining form a surface coating and small pools over the exposed steel surfaces in both the cooling system and the reactor vessel. The issue that needs to be solved is to remove these residues without generating excess hydrogen off-gas concentrations or pressure pulses from unstable reactions and to convert the entire residue to hydroxide. It is then possible to flush the hydroxide with a water rinse after which final dismantling can commence.

Measurement Methods

Measurement of hydrogen off-gas is done with the help of a Systech 542 programmable hydrogen gas analyzer. The development process by NNC passes low-concentration water vapour that is carried by nitrogen over the contaminated surfaces to react with the alkaline metals. Hydrogen off-gas is produced by the reaction. The first Systech 542 programmable analyzer was acquired by NNC in 1994. From then, a number of design changes have been made by Systech design engineers to meet the specific needs of the development program.
The method followed is detailed below:
  • Hydrogen-off gas is measured by two Systech 542 programmable hydrogen gas analyzers that indicate remaining contaminant levels.
  • The coolant and water vapour react to produce sodium hydroxide and potassium hydroxide as well as hydrogen off-gas.
  • Two Systech 542 programmable hydrogen gas analyzers measure the amount of hydrogen-off gas produced, which indicates the amount of remaining contaminant.
  • The gas analyzers have two alarms that can be set to high or low level. The alarms on both the analyzers were used by NNC as a high-level and an extremely high level such that if there is high or very high hydrogen off-gas concentration, it is possible to set automatic trip levels.
  • Analogue outputs obtained from the Systech 542 hydrogen gas analyzers provide data for logging.
  • The Systech 542 hydrogen gas analyzer is provided with settable analog outputs that are recorded on a data logging system. As NNC is normally interested in low hydrogen off-gas levels, but also the high levels need to be recorded, the analog output ranges of both the instruments are different, one high and the other low-sensitivity.
  • It is essential that Systech 542 hydrogen gas analyzers are precise and stable at both high and very low concentrations of hydrogen off-gas.

The Warrington Test Rig Experiment

NNC is presently running a test rig at its Warrington facility to evaluate the effectiveness of the process under operating conditions and to determine operational parameters that can be transferred to a full-scale unit. It is important that Systech 542 hydrogen gas analyzers used for monitoring the decontamination process progress and monitor safe venting are stable and reliable at both low and high concentrations of hydrogen-off gas.
The Systech 542 hydrogen gas analyzer, the most critical application for the decontamination process is used to measure low levels of 10 ppm hydrogen in nitrogen. At these low concentrations, instrument drift can pose to be a major problem. It was observed at Warrington that there was a drift of 20 ppm because of changes in ambient environmental conditions between day and night. The impact of instrument drift has been minimized in the NNC rig by running the 542's auto-zero program at predetermined intervals.

Conclusion

Systech 542 programmable hydrogen gas analyzers are critical in developing a process for safe decontamination of reactor system components. The consultant engineer of NNC has described the Systech 542 programmable hydrogen gas analyzers as the most important element in the system and it is proving to be a key component in the development of the process for the safe decontamination of reactor system components from the Dounreay Fast Breeder Reactor.