The City of Houston has selected planning, engineering and program management firm Lockwood, Andrews & Newnam Inc. (LAN) to develop...
The Abita Brewing Co., founded in 1986 and located just north of New Orleans, is a rapidly growing brewery with specific manufacturing obstacles directly related to its aggressive environment.
“By nature, everything here is constantly being exposed to many elements,” said James Franklin, Abita’s plant engineer. “All enclosures used are of NEMA 4X construction because of water, caustic, acid and bleach that are regularly used during cleaning procedures.”
“Abita also literally has its own weather system,” Franklin continued. “Because of the constant moisture in our facility, some days have actual clouds in the top half of the building. The result is that ferrous metal products corrode at a very high rate. The plant-wide specification is to use non-metallic enclosures in all areas.”
As a result of these environmental conditions, Abita has within the past seven years used or replaced metal enclosures with more than 50 Stahlin fiberglass enclosures.
"It makes sense to use them up front and forget about it,” Franklin said. “Non-metallic enclosures cost less; in addition, they are lighter weight so we save on shipping.” Franklin also explained that a pry bar had to be used on an OEM metallic enclosure to open it after the three-point latch mechanism had become “frozen” due to corrosion. This enclosure currently is scheduled for replacement.
“Although longevity and cost are key factors, I also am concerned with ease of workability,” Franklin said. “Stahlin performs factory modifications to accommodate distribution, starters, drives and other automation. The enclosures are much easier to modify using conventional tools."
Crusher Solves Ash Handling Problem
When Parsippany-Troy Hills Township Utility’s decades-old sewage sludge incinerator’s wet ash handling system required replacement, they decided to go to a dry ash system. Arrangements were made to truck the ash to a disposal facility that could recycle it for use as a soil conditioner. A dry system to handle the ash without slurry water was required. In the design of the system it was decided that an ash crusher was necessary in order to transport the material using pneumatics.
During the process of incinerating sewage sludge, “clinkers” of various hardness and sizes occasionally form in the ash stream. It was important to reduce the size of these clinkers. The machine would be subject to an extremely abrasive service and have to operate under high temperature condiditons. It would be necessary to reduce the ash to a required 1/4" particle size. Further compounding the challenges of this application were the occasional pieces of tramp metal that would inadvertently get into the system and could potentially cause havoc on a machine.
Franklin Miller was called to provide a solution. Working closely with the Parsippany personnel, Franklin Miller devised a modified unit that became the Delumper Model HM. This unit was capable of reducing the abrasive ash and clinkers down to 1/4* with minimal wear. In addition, it could handle occasional tramp metal as well without damage.
The facility reports that the Delumper has provided more than two years of trouble-free operation. In fact, cutter wear on the unit has been extremely light.
Screenings Processing System Eliminates Remote Disposal Costs
Installation of a new system that grinds, washes, compacts and dewaters bar screenings at the Meriden (Conn.) Water Pollution Control Facility (MWPCF) has dramatically reduced organic content and overall volume, eliminating remote landfill disposal costs while also significantly reducing handling needs and odor, according to the plant’s manager.
The Screenings Washer Monster device, installed last May as an alternative to a procedure forced by closure of an adjacent landfill, is manufactured by JWC Environmental of Costa Mesa, Calif.
“Before the landfill adjacent to our site was closed, all we had to do was haul the screenings over there in our own 8 cu. yd. truck,” recalled Robert T. Mercaldi, Assistant Director, Water Pollution Control Division, Dept. of Public Works, and manager of the 11.6 mgd plant. “After the closure, we had to find a company licensed to haul over the road, certify testing for a list they gave us of screenings parameters to be analyzed, rent a 15 cu. yd. specially-lined dumpster for $1,200 a month and pay landfill drop-off charges ranging from $40 to $50 a ton at sites in Ohio, Pennsylvania, and New Jersey. Meanwhile, we had a complex new task to take care of in the plant, moving around solids heavily loaded with organics, with heavy odor,and requiring double and triple handling.”
Mercaldi heard that a grinder/shredder already in use in digesters might be used at the front end of the stream in the inlet, but he was concerned about possible reaccumulation of solids in the digester, causing plugging of pumps and heat exchangers. The state did not like the idea and strongly discouraged it. Then he found out that JWC Environmetal had developed a new piece of equipment for just this situation.
MWPCF installed the new unit without the need for any outside contractors, including all wiring and controls. “We just had to retorque the drum head for the augur conveyor one time when the LED light told us to. It’s basically totally unattended,” Mercaldi said.
“I was a little concerned when nothing had come out the end for the first five days after startup, but I also noticed there wasn’t any odor,” he continued. “Finally, a very dry solid resembling shredded newspaper extended six or eight inches above the exit chute like ashes at the end of a cigarette. That fell off into a bin and was bagged up for disposal as special waste.”
Since the Screenings Washing Monster went online, MWPCF has been able to reduce the weight of its bar screenings from eight tons per month to 660 lbs. per month, and their volume was reduced from 15 cu. yd./mo. to one cu. yd./mo. In addition to eliminating the cost for the out-of-state dumping and all the extra work the company was doing with a backhoe, front-end loader, wheelbarrows and the dumpster, MWPCF no longer needed the bar screen at its pump station. All the screenings formerly removed there can be pumped to the inlet building where the new unit is.
Mercaldi said his two remaining bar screens are fine types, with 11/2" spacing, and automatic raking systems. A single chute receives scrapings from each screen, with effluent water piped in to push them into the Screening Washer Monster’s square-funnel hopper. They then move through a grinder, and into a wash box, where a high-pressure spray cleans the ground up particles and washes out organics. Compression and dewatering follows, with more water squeezed out in the tapered exit chute.
The Screenings Washer Monster is a self-contained unit that can effectively process screenings that have been captured by bar screens or other screenings removal devices. Discharge is virtually free of organic (fecal) matter, with the exit plug typically 40 to 50 percent dewatered and reduced in volume by about 75 to 80 percent.