Do Nothing

by Mike Dill

The calendar says winter officially starts on December 21^st. That was before the wacky season. What do I mean by the wacky season . . . well for the past few years would you call the weather predictable, or the four seasons? Little or no snow, heat that goes on and on. No rain for months and then six inches in twenty days. You can blame it on climatic conditions in the western Pacific or melting of the ice caps, pick one or name your own. It doesn’t make any difference, whatever the weather, you have to go with the flow. Weather plays an important role in plant operations. Seasonal change in the spring and fall could mean a period of upset. Spring rains and snow melt combine to intensify inflow and infiltration. Warm weather means less DO and possible filamentous problems or elevated ammonia levels. Each season has impact on the treatment process, and how we deal with it.As we travel around the state or respond to phone calls, we are hearing, "I don’t understand, this usually doesn’t happen or things just won’t settle." In our business, the words won’t settle, are heavy duty. We received calls this past December about filamentous and how that is a summer problem. Think back to December and how warm the temperatures were. Cloudy effluent or bulking sludge and process control tests that do not have expected results. One operator said to me, "it’s like I started my career yesterday, this plant has never acted this way. I don’t understand." Welcome to the wacky season.Go with the flow means adjust, make changes, don’t get excited, it will straighten out, usually the plant comes back. Most times that is true, the plant comes back, and minor upsets are self-correcting. That shows that the process can adjust to changes and adapt, but what happens when the plant can’t or won’t adapt, that’s when the operator becomes very important.Your job is to predict what’s happening, make adjustments or changes that will help the process adjust and accept the change. Plants are designed with loading rates to reduce the waste and return a useable effluent to the receiving stream. Remember it is a biological process and if interferences occur there will be reactions, usually bad. Biological means naturally occurring, until something prevents or changes the process. Filamentous will do that. Low DO’s or pH balance can be blamed. Sludge return rates, acid / alkalinity ratios, SVI’s, F/M, these are things the operator has control over. Sometimes other things hinder the operator’s ability to control a situation, such as, a lack of knowledge or not the right equipment. In the biological process, the most important thing is the ability to analyze and then make the necessary adjustments. One small adjustment can make a major change. Return rates will have a huge impact on the F/M ratio. Perhaps the volume of sludge is the same, but what is the concentration and age. Volatile mass versus respiration rates.

In the activated sludge process, and that includes most plants from lagoons to the most sophisticated operations, the biological process is in play, so don’t say I don’t need to understand activated sludge, it’s not my plant. If you got bugs, you got biological process. A good activated sludge education, and following the principles of it, will help in times of upset or making adjustments to the process. One of the most frequently used pieces of equipment in the treatment process should be a microscope. Scope and a bug chart can make you look like a genius. If you don’t have a scope, then try to borrow one on a regular basis. Maybe your local high school science department can help out. (I know you graduated from that school and pledged never to return, well don’t overlook a valuable resource). You can purchase an excellent reconditioned scope for about half the cost of a new one. Do not go cheap. This is one piece of equipment that should not be low bid. The microscope should have a viewing power of 10X, 43X and 100X, (X being magnification power). If you are thinking of collecting a sample and driving to a neighboring plant, be careful. Any biological sample must be immediately stored at 4°C until analyzed and should be done ASAP. However, do not rely solely on the microscope. You have other tools at your disposal. Slowing or timing return rates, wasting more or less. It’s all part of the process. For those of you who have attended my math class, remember when we talked about percent and part of the whole? P divided by W times 100, equals percent. Well if any part gets out of balance, then the whole will change and require adjustment. It’s a big pie with many pieces or a balanced load that can tip at anytime. Usually everything stays balanced, but when the part starts to change, thus affecting the whole, it’s time to start checking, looking, observing, sampling, analyzing, interpreting and making the necessary adjustments. The only thing that is wrong, is to do nothing.