Wastewater Treatment – Clarifying the Choices

Companies should consider such factors as space and capital requirement, desired filtrate quality, and level of automation when selecting water and wastewater filters.

Filtration is the easiest way to remove solids from water and wastewater streams. In wastewater systems, filtration is used to decrease suspended solids entering the publicly owned treatment works or water-reuse systems or to increase solids in sludge dewatering applications.

Filter selection begins after a company determines the required level of filtration or filtered water quality; decides whether filtrate will be disposed or reused; identifies how much space is available; calculates the amount of capital available to purchase, operate, and maintain the system; decides whether the system should be automatic or manual; and considers any pertinent water conservation requirements.

The level of solids removal or filtered-water quality desired defines the type and size of filter necessary; most are available with varying automation levels and price ranges.

Proper filter size is determined by flow rate and the amount, size, and type of solids to be removed. Particle sizes and filtration levels can be determined by filtering water and solids through varying sizes of filter paper and measuring the total solids content of filtered water.

Solids remaining in filtered water will be the same size or smaller than the last filter paper used and will indicate which filter media opening size to use. (A filter manufacturer or laboratory can be hired to perform this procedure.) The number of solids in water or wastewater can be determined by a laboratory analysis of total solids; flow can be determined from plant records or an in-line flow meter.

The following equation is used to calculate solids loadings (how quickly a filter will load with solids): solids (lb/h) = flow (gal/min) x total solids (ppm) x (8.34/60/1,000,000).

After solids loading, filter area, and filter media opening size have been determined, the amount of time required before cleaning, or back-washing, should be calculated, and the fate of filtrate waste must be determined.

In other words, after a filter is backwashed, where will wastewater go? Backwashing often requires up to 10% of the total filtered volume, a 10:1 ratio. For example, 379 m3 (100,000 gals) of filtered water would generate 38 m3 (10,000 gals) of backwash that contains concentrated solid and may require additional treatment.

Some Wastewater treatment must be pretreated before filtration. Oily wastewater, for example, tends to agglomerate quickly between or over filter media and requires conditioning before filtration. Fine-grade filtration systems are susceptible to fouling from biological growth, yeast, and other microorganisms; performing bench tests or consulting with filter manufacturers about specific applications is recommended.

Hiring the right electrician for the job

This is a brief guide for helping you chose the right electrician for your home. Hiring a company to do electrician services for your home or business can be a very stressful decision. What if you choose the wrong company and something terrible happens down the line? This article will help provide a good step-by-step method for choosing the right electrician for the job. So think positive thoughts… it will be okay!

STEP ONE: Get their credentials!
Electrician services companies working in your home or office must be licensed and insured in case of issues. Every electrical worker you consider hiring should be insured, bonded, and licensed. They should be very willing to let you know their individual state license number. Also, always check to see if they have the appropriate insurance for general liability and workers compensation.
TIP: The great hazards of hiring an uninsured electrician are enormous. What would happen if that “pal” of yours who “knows a lot about electricity” gets really hurt while in your home or your office? Well, more often than not, it is you who would be held 100% accountable for any injuries that happened while on your property.

STEP TWO: Get Those References
Don’t be shy to ask for and check their references! You want to make sure that the company has a history of doing good work in the community.

STEP THREE: Take a look at their employees.
More often than not, the best electric service companies insist all of their electricians are regularly drug-tested and background checked. This is a good indication that the company has your interests in mind before theirs. This process is quite an investment on their part, and it tells you right away that they have invested a great deal in their own electricians.
TIP: See if the company is on any “best places to work” lists in your region. A great place to work means that the employees are treated well and respected.

STEP FOUR: Always get a price up front
Believe it or not, you won’t get the best price by bidding the project around to multiple companies. Call ones that you are interested in, and get a feel for their customer service (a live person answering the call is always a good sign!) THEN call only one out to your home or office to give you an estimate. Some of the electrician companies are offering first-time discounts for first customers, and if not may usually try to get your repeat business by cutting the costs of the first job.
TIP: You want to develop a good, long lasting relationship with an electrical services company. It is an almost certainty that you will call them more than once during your time in your home or office.

STEP FIVE: Knowing you called the right one.
Look out for the following when that electrician comes to your home the first time:

A stellar local electrician will ALWAYS arrive at your door in a sparkling uniform. The more professional companies insist that their workers carry enough clean uniforms so that they can change after every job if one gets dirty.
A good electrician company will have printed materials with their telephone, company name, license number printed somewhere.

A good electrician Bristol will NEVER EVER perform a job without getting the correct permits. Sure, you can usually get someone to do the project less expensively and faster by not getting permits, but it puts you and your family/employees at great risk when you do so. Also, what happens if you don’t pull permits and something goes wrong, like a fire? Chances are that your insurance company will research that the correct permits were in place, and, if not, you may not be covered!

A stellar electrician company will always call you back within a business day or less, provide a well documented written estimate outlining all costs, and put a time frame on the estimate as well.
TIP: Suppose the project unexpectedly gets out of hand at some point, and through no fault, on anyone’s part you have to spend more to get it done. A great electrician company will stop and provide a written addendum to the original estimate so that you know all new costs before commencing…

A stellar electrician company will always listen to what you need, and then make recommendations based on their experience. There are many things that need to be taken into account for a rewiring project, such as (high wattage kitchen work lights, types of bulbs in the project, vacuum cleaner usage, existing electrical wiring, etc.)