The goal of the project was to install highly accurate modulating valves and related controls to maintain a constant temperature in each of the vats. The economic motivating factor was cost. The facility maintains a 200HP fire tube package boiler and was incurring natural gas bills in excess of $13,000 per month. This natural gas usage is in excess of the national average for a similar facility. Mangers recognized that overheating of the vats due to inoperable and inaccurate temperature control was a major source of energy wastage.
The facility selected a high end temperature control solution. Modulating valves which accept a 3-15psi air signal based off of temperature feed back from RTDs were installed in each vat. Blue Sphere designed and built a customized control panel including seven stand alone PID controllers and I2P transducers. The control panel interpreted the temperature feedback from each vat and produced a corresponding 3-15psi output to the steam valve on each vat. Using a PID loop, the steam valves apply only as much steam to the vat as is necessary to maintain the target temperature. This solution has effectively eliminated steam wastage at the facility. Steam control systems are available from Blue Sphere Water Technology.
Steam Control Valve Assemblies
Complete with Y-Strainer Ahead of Valves and By-Pass
There are many high end dewatering solutions on the market. Screw presses, filter presses, belt presses, gravity thickeners, centrifuges and thermal dryers to name a few. Minimization of solid waste disposal remains a high priority for anyone who owns or operates a water treatment process. Each of these technologies yields valuable results in large scale operations.
However, we encounter many small scale operations which simply do not have the volume of wastewater to justify such a capital expenditure. Even if a company can afford the capital cost, they rarely have or wish to allocate additional skilled labor to run such a device. The cost difference of fielding a skilled, well compensated operator versus the most economical one can eliminate the savings generated from additional dewatering in small scale pre-treatment plants.
For this reason, the dewatering method of choice for many pretreatment plants which operate in the 50gpm range is the simple dewatering box. With no moving parts and producing reasonable degree of solids thickening, this is a logical alternative and is successful in many markets.
We have encountered a unique dewatering box that is designed for an exceptionally long service life. The box features stainless steel internals and is banded with traditional epoxy coated carbon steel. This blended use of materials insures that the box will provide 20+ years of service and is ideal for higher mineral content or aggressive waste streams. For a relatively minor difference in capital cost, a facility can field an asset with a much longer functional lifespan by choosing this container.
These boxes are available with rolling hard and tarp style tops and fabricated to general DOT specifications.
For more information on this specific dewatering box contact: www.bluespherewatertechnology.com
In the past two months, Blue Sphere has sold, installed and commissioned several of the Siemens Micro Master variable frequency drives (VFDs). While we do not offer this drive exclusively, positive experiences with the equipment in the field are forcing us to consider it. From a stand point of integrated features for the money, this VFD provides the best value we have found.
Lets face it, we all dread programming VFDs. Its just something about the 400 page technical manuals. While there are some dirt simple drives on the market which we endorse. (The integrated drive on the Grundfros stack pumps comes to mind.) There is significant value in integrating a complex, upper end VFD for mission critical processes.
The standard features of the Micro Master series which have very practical uses in the field include:
• A series of read only parameters which display incoming, out going and the DC conversion voltage. Its like having a secondary volt meter.
• A removable LCD interface called the BOP. If a screen is damaged, a replacement is only $60 and can be changed out in two minutes. This also allows for a very quick trouble shooting procedure.
• The internal current monitors automatically shut down the drive in any conditions which would damage it. The programmer has high degree of control over the series of conditions. The investment in one of these drives is protected by the software.
• In addition to the wide array of control options available on all modern drives, the Micro Master has integrated PID functions, which are perfect for automated flow rate applications and set point based chemical addition. This can be done without a stand alone process controller or PLC, saving capital.
If interested in the Micro Master VFD series, please contact Blue Sphere Water Technology.
Blue Sphere Water Technology was recently challenged by a client in the Cotton Yard production industry to reduce their facility water consumption. As is typical with most textile operations, this plant regulates temperature and humidity on the production floor using air washers, cooled by a chiller and tower system. The capacity of the system is 1300 ton or roughly 15.6 million BTU/hr.
The facilities single largest consumer of city water is the cooling tower. The tower runs at maximum capacity over 90% of the year. The tower runs at around eight cycles of concentration and draws approximately 35 gallons per minute (gpm) of makeup water nearly around the clock.
The facility is located in humid, South Western Louisiana. This means that for the bulk of the summer months, the facility air washers operate in a dehumidification mode. This mode pulls water vapor from the plant air and imparts it into the chilled water reservoir within the air washer. When the air washer operates in a dehumidification mode for extended periods of time, the chilled water overflows to drain.
The purpose of the reclamation project was to recycle the air washer overflow. From a point of water quality, the air washer overflow is nearly ideal. The water has virtually zero mineral content and no suspended solids. Additionally, the water is chilled to approximately 50F.
To accomplish the reuse goal, Blue Sphere installed a simple, air powered, polypropylene double diaphragm pump (AOD). Chilled water in the air washer is preferentially drawn in by the AOD pump and supplied to the cooling tower before it can overflow into the drain. The outlet of the plumbing in the cold water basin of the cooling tower is outfitted with a simple mechanical float valve. The AOD pump runs constantly as it is not damaged by drawing air into its suction. The selected AOD pump has a maximum capacity of 4gpm, but has been dialed back to approximately 2gpm.
Our initial estimates calculate that the facility will save 20,000 – 40,000 gallons of water per month as a result of the economical project. The temperature drop across the condenser will also be closely monitored in the coming months to determine if the low temperature of the recycled water has a positive impact on tower performance.
Part One: A brief background on the conditions which gave rise to this new market.
Petrochemical plants have traditionally depended upon outside environmental firms to come onto their property and perform cleaning operations on heat exchangers. These regular scheduled cleanings help the facility maintain efficient heat transfer and thus keep production BTU costs at a minimum. The environmental firms which engage in this sort of service employ highly trained, safety orientated personnel and specialized mobile hydro blasting equipment. There are stringent lockout, flange blinding, air quality monitoring and fail safe procedures in place to protect the environmental firm personnel and the capital equipment. However, the possibility for equipment damage or a lost time accident always exists. Therefore, both the facility and environmental firm must have sufficient insurance coverage to minimize their exposure to these risks. For the purpose of this discussion, we can refer to the first motivating factor for a new market as Decreased Liability for the petrochemical plant.
The primary method of cleaning heat exchangers is hydro blasting. Hydro blasting is essentially a “super pressure washer” operating in the 40,000psi range. This process is effective, but of course produces a wastewater stream. The materials removed from the heat exchanger will generally precipitate as solids which are characteristically hazardous waste or K listed waste (in the case of most refineries). A “PRODUCT” becomes a “WASTE” the minute it hits the ground during a cleaning procedure. The place or facility where that product hits the ground is called the “Generator”. In cases where the waste is considered hazardous, the Generator must compile with the stringent reporting, handling and disposal procedures set forth by their state DEQ. Additionally, many states are incorporating mandatory hazardous waste reduction programs for their large Quantity Generators. Reference the Texas P2 Plan as great example of this trend. In the case of outsourced heat exchanger cleaning, the cleaning facility is considered the Generator, not the origin facility. We can refer to the second primary driver for a new market as Decreased Hazardous Waste Production for the petrochemical facility.
The two primary motivating factors for a new market in off-site heat exchanger cleaning:
Decreased Hazardous Waste Production
Blue Sphere customer Cleanco Systems recognized the potential for a shift in how heat exchangers are cleaned and the resultant waste is handled. As the early innovator in the market, the Houston TX area based Cleanco, invested significant capital in a ground up facility dedicated solely to hydro-blasting heat exchangers and producing as little hazardous waste as possible in the process. This business model was well accepted by the major refineries and has been quickly copied by other heat exchanger service companies. Significant capital is flowing into the construction and operation of heat exchanger cleaning facilities throughout the Gulf Coast.
In Part Two we will discuss the particular water treatment technologies competing against each other in this young market.
The above helpful chart was generated for operators of a Dissolved Air Floatation (DAF) unit using 48% Aluminum Sulfate Solution (ALUM) as a coagulant. This DAF operates in business of “for profit” water treatment. Meaning that their business model is to evaluate and treat wastewater streams which are hauled to them. Because of the difficult nature and high solids content of these waste water streams, dosages of coagulant can approach or exceed 5,000mg/L.
The chart was calculated for ALUM (specific gravity 1.33), but will provide close dosage approximations for other aluminum salts as well. All Operators are welcome to download utilize it as they see fit.
There is a strong, underlying market trend that industrial wastewater treatment chemicals are losing their “specialty” status. It started with the largest polymer users. Mammoth product consumers such as the City of New York, gained an understanding of the charge and molecular weight of dry polymer product they were using. In a bidding war between the various large producers of that time (around 2002) for their business, the largest users where offered pricing that in some cases was actually below product cost. The volumes help base load the factories however.
Then followed a series of acquisitions and consolidations. Bellwether names such as Stockhausen, were swallowed by larger commodity houses. In most cases, commodity salesmen were empowered and encouraged to go forth and market the products, replacing the specialized polymer representative. Most large commodity dealers retained at least one trained polymer applications person and they “bring in” that person on an as needed basis for trouble shooting.
These changes are a natural progression for any technology to make as it reaches maturity. Blue Sphere Water Technology recognizes this trend. Blue Sphere distributes water treatment chemicals with full transparency of the product properties, including percent charge and molecular weight. This allows informed purchasing agents and engineers to quickly identify and purchase the products they need, at deep value, without waiting on a “specialty” chemical representative.
Polymer products are available at www.shop.bluespherewatertechnology.com
Polymer products are available at www.shop.bluespherewatertechnology.com
Blue Sphere was recently challenged to design and implement a level control system for a wastewater stream which contained large amounts of adhesive. The adhesive has a tendency to dry/set up upon tank walls, traditional float based level switches and everything else it comes in contact with. For this reason we needed to use an economical no-contact level sensor.
While there are many radar based transmitters on the market, most of the devices are costly. It would not be uncommon to pay more than $1,000 per sensor. Upon conducting a little research, Blue Sphere selected the Flow-line Ecopod DS-14 for use as a high level alarm switch. The DS-14 seems to provide sufficient functionality and economy. The units sell for around $350 each.
Blue Sphere personnel have utilized Flowline equipment in the past with poor results. Early Flowline model transmitters where difficult to commission in the field. The set points had to be measured off of a wall with a tape measure. Additionally, we found the structural integrity of the housings to be poor. The clips which held the lids on would break thus allowing water into the device.
However, Flowline appears to have engineered out those particular issues with the DS-14. The unit is small, watertight and rugged. Programming is accomplished via a laptop with a little FOB interface that only costs $50. We are excited to put this device to work in the field and report on its performance. Six of the DS-14 level switches are being installed and will be tied to a small customized PLC control system.
Ohio is the latest state to close injection wells used to dispose of wastewater after the state experienced several minor earthquakes near Youngstown last weekend, according to an article by Daniel Gilbert for the Wall Street Journal.
The wells accommodate a growing amount of wastewater left over from hydraulic fracturing, and the decision to close the wells could spark political debate about the practice.
Ohio regulators ordered the closure of the Youngstown well, D&L Energy Inc., to stop injecting wastewater after the state was hit with a 2.7-magnitute earthquake on Dec. 24. When a 4.0-magnitude earthquake struck again that evening, the state declared a moratorium on all injections within a five-mile radius of the well.
Northeast Ohio has no known history of seismic activity, and 2011 was the first year that a majority of the waste injected underground was from out of state. The natural-gas industry, however, has no evidence these activities are causing earthquakes."
While it will be difficult to prove that deep well injection is causing earth quakes, a prohibition on the technology would be a victory. Prior to the 1970s series of environmental reforms, it was common practice to take barges of garbage and hazardous waste out to sea and dump them. Massive quantities of sewage continued to be discharge directly into water bodies as late as the 1990s. Today we view these practices as absurd. They are from the environmental dark ages.
It is hard to believe that in 2012, a valid and legal solution to wastewater disposal is still deep well injection. The “pump it so far down that our great grandchildren will have to deal with it” attitude is alive and well. The disturbing thing is that the technology for treatment and reuse of these waters is available. Legislation needs to demand recycling and reduced environmental impact from the drilling and hydro-fracturing process. If it drives up the cost of natural gas so be it. It is a cost we have to pay.
In fairness to deep well injection sites, the waters which they receive are required to meet certain criteria. The sites are not just dug any ware. There is a permitting process which requires full scale geologic studies. However, no one could argue that the oil field exemptions for disposal of wastewater in this fashion are extremely lenient. The difference is especially clear when compared to the wastewater disposal options available to other industries.
Blue Sphere Water Technology has started this Blog as a medium by which to bring new technologies, ideas and viewpoints up for debate and discussion. We will focus on the field of water treatment of course. However, any sub category is likely to be discussed. These may include; municipal wastewater treatment, industrial pre-treatment, process water preparation, drinking water treatment, industrial recycling projects, boiler water treatment and cooling water treatment.
As the name “Cost Per Thousand” implies, we are interested in the practical technologies which can and should be implemented on a large scale. We will cover areas from the smallest, yet effective and reliable chemical dosage systems to the largest recycle and reuse concepts for heavy industry. We encourage your thoughtful comments and feedback.
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