Wastewater treatment solutions, Question and answers

Wastewater treatment solutions,

Wastewater treatment solutions, Question and answers

Q: What are my best options for treating grease problems?
A: Grease problems are treated using the same solubilization concept as used with sludge eduction.The most common products used to treat grease are GelPac G, GelPac LS, and LLMO G-1. GelPac G requires use of a delivery system, and will delivery optimum results. GelPac LS is used without a delivery system, and while not quite as effective as the GelPac G, it is an excellent solution when water and electricity are not readily available. LLMO G-1 is generally used when the wastewater flow at the point of treatment is greater than 1 MGD.

Q: Can you help with a BOD removal problem?
A: The LLMO E-1 and GelPac S products are particularly helpful in improving BOD removal when the plant is subject to high strength waste, toxic shocks or hydraulic washout. The addition of the LLMO E-1 or GelPac S will help degrade high strength wastes and result in improved effluent quality. They also provide buffering to minimize the effect of a shock load, toxic influent, or washout. Also, recovery time from the shock is reduced significantly with LLMO E-1 or GelPac S in use. The net result is better average BOD removal performance.

Q: I occasionally have problems meeting my nitrification permit. Can you help?
A: LLMO Nitrifiers and NitriGel Cartridges are recognized worldwide as the finest nitrifying bacterial productsavailable.The best time to use these products is when you need to restart nitrification after an upset, or to meet a seasonal permit. Also, if a plant is partially nitrifying but cannot quite meet its permit, use of these products will usually result in compliance.

Q: What are LLMO and GelPac products?
A: LLMO products are liquid based products and have been manufactured since 1974. The LLMO line includes LLMO S-1 for sludge reduction, LLMO G-1 for solving grease problems, LLMO E-1 for efficiency enhancement and plant start-ups and LLMO N-1 for improved nitrification.

GelPac products, introduced in 1990, consist of nutrient and bacteria laden gels plus a vial of concentrated starter bacteria. GelPacs include two models which require delivery systems (GES Automatic Bacterial Delivery Systems) and one model which is used alone without a delivery system. The models which require delivery systems are GelPac S for sludge reduction and GelPac G for grease removal. GelPac LS, which does not require a delivery system, is for grease reduction at remote sites or where electricity and water are not readily available. A fourth gel product, NitriGel Cartridge, is used along with LLMO Nitrifiers in the GES Nitrification System.

Wastewater treatment solutions, Question and answers

Q: How does your sludge reduction and grease reduction technology work?
A: The first point to make is that particulate waste (suspended solids or grease accumulation) is much more difficult to degrade than simple soluble waste. It is the particulate waste rather than soluble waste that results in excess sludge production or grease accumulation. For example if you add 500 mg of glucose (a soluble substrate) to a 1 liter flask with 2500 mg/liter of MLSS and aerate the mixture for eight hours, you will find that the MLSS has increased only by 100 mg/l or so. However, if you add 500 mg of cellulose (a particulate, suspended solid), to the same flask, the MLSS will increase by 500 mg/l after eight hours of aeration. GES technology works primarily by converting particulate waste into easy to assimilate, soluble waste through a process known as solubilization.

Q: Why does treatment of soluble substrate produce less sludge than does similar treatment of an equal weight of particulate substrate?
A: The simple fact is that soluble substrate is removed by bacterial action, while suspended substrate cannot be directly consumed by bacteria. Bacteria have a semipermeable cell wall that prevents large, complex particles from getting inside the bacterium. Suspended solids or colloidal material is too large to pass through the bacterial cell wall. Simple soluble substrate, however, is directly consumed by the bacteria. Once consumed, most of the soluble food is converted to CO2 and water, which means less sludge is produced. Suspended particles are simply deposited as grease, fat, and scum accumulation in traps or pipes, or trapped in the flock and measured as an increased amount of sludge in activated sludge.

Wastewater treatment solutions, Question and answers

Q: So how can I reduce my sludge production and grease accumulation?
A: The key is solubilization. In the process of solubilization, colloidal and suspended solids can be converted into low molecular weight soluble compounds. Once this conversion occurs, the bacteria can use the substrate as a food source and convert part of it to CO2 and water. The bottom line, which is well documented in the scientific literature, is that if you enhance the rate at which colloidal and suspended organic substrate is solubilized, your sludge production will decrease and grease accumulation will be minimized.

Q: What causes solubilization?
A: Many bacteria have the ability to produce enzymes which are then excreted into the aqueous environment. These enzymes are known as extra cellular enzymes. Extra cellular enzymes hydrolyze colloidal and suspended organic compounds, and release a low molecular weight, soluble food source which the bacteria can directly assimilate.

Q: O.K., I need extra cellular enzymes to increase solubilization to get lower sludge production and grease accumulation. These enzymes are made by bacteria, and I have plenty of bacteria. Don’t my bacteria already produce extra cellular enzymes?
A:While many bacterial species produce extra cellular enzymes, they are not produced at all times. The extra cellular enzymes are generally produced only under stationary or death phase conditions. As long as soluble food is present and the bacteria are growing and reproducing, they do not produce extra cellular enzymes in appreciable quantities.

Q: Why do GES bacteria produce large amounts of extra cellular enzymes?
A: GES has a U.S. patent on its special process for forcing bacteria to produce increased amounts of extra cellular enzymes. The process involves starving the LLMO or GelPac bacteria in an aerobic, nutrient deficient environment before the bacteria are added to the wastewater to be treated. The GES bacteria have been selected for their potential to produce large amounts of the right types of extra cellular enzymes. Use of the GES solubilization patent maximizes this potential, and forces the bacteria to produce the desired enzymes at maximum rate.

Q: What extent of sludge reduction or grease reduction can I expect from using the GES technology at my plant?
A: It depends on the configuration. In general, for secondary treatment facilities, results improve as the aeration detention time increases from conventional to extended aeration mode. With conventional activated sludge, expected sludge reduction ranges from 15% to 25%. With extended aeration, typical sludge reduction ranges from 25% to 50%. As for grease traps and collection systems, you can expect that your required pumping frequency will be extended dramatically. Situations such as going from pumping once per month to once every 6 months or more are common.

Q: Will this technology work with my RBC or trickling filter? And should I choose LLMO or GelPacs for my facility?
A: The process works well with both RBCs and trickling filters. As with activated sludge, the longer the secondary detention time, the better. As for the LLMO as compared to the GelPac, LLMO products are generally used when the flow at the point of treatment is greater than 1 MGD, while the GelPacs are designed for the small volume WWTP (1 MGD or less). There are exceptions to this guideline. For a recommendation on your situation.

Wastewater treatment solutions, Question and answers

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