为了升级和扩大其每天处理320万加仑废水的工厂的可持续性，大颈水污染控制区的项目团队有一个高大的障碍，可以清理障碍 - 维护为25,000名长岛居民提供服务的设施。

The multiprocess wastewater treatment plant in Great Neck, N.Y., has upgraded other features in the past, but the current $15-million project, which began in late 2018, will have an outsized impact—harnessing the facility’s normal operations to generate power for half of its total energy use.

这项工作需要添加新的75 kW共同生成微涡轮机；取代厌氧消化酯设备，该设备通过分解废物以及相关的电气和机械组件来产生甲烷气体；并建立商业润滑脂废物摄入系统不仅会产生收入，还可以支持增压废物到能源技术。

Great Neck District的工厂负责人克里斯·墨菲（Chris Murphy）说，当团队解决该项目的各种元素时，它必须使该设施充分运转。他说：“每当您在废水处​​理厂进行施工时，您都不会从常规治疗要求中得到缓解。”“这就是这是一个非常令人兴奋的建筑项目的原因之一。这不是典型的市政升级。”

设计工程师兼计划经理Gannett Fleming的项目经理Dan Capano说，该团队为该项目的核心选择了一个分阶段的安装策略 - 重建了Great Neck的三个厌氧消化器系统。他说，这项工作始于去年，从第3号旧消化器系统（第3号）开始升级和康复。他说：“分期确保了工厂的运营不受损害。”

Gannett Fleming项目工程师Jiangzhao Zhang说，该计划的关键过渡将于今年春季初发生，当时新的3号消化器系统即将到来。“Once we turn on the new digester No. 3, which has better heat and mixing systems with more capacity, then we’ll have larger capacity to take more solid waste, and we will have the capacity to take the old 1 and 2 digesters off line.”

Before making the switch, the team will check that the new higher-capacity digester No. 3 system can not only process wastewater sludge, but also generate ample methane gas to power two existing microturbines Gannett Fleming had installed in an earlier 2014 project.

When all systems are go, the team will start upgrades to the other digester units, according to Capano. “If all goes well, we take them off line in April and bring the new equipment back on line in June,” he says.

Staging the installations also means Gannett Fleming has to coordinate overlapping schedules as contractors focus on their pieces of the puzzle, Capano says. “It’s a challenge when you have jobs with multiple prime [contractors] on site.”

其他项目团队成员包括WHM管道和供暖，JVR Electric，Harbor Mechanical以及D＆B工程师和建筑师。

优化潜力

新项目超出升级旧的消化er systems and adding new capabilities, Murphy says. It’s a concept that has been on the Great Neck district’s radar for more than a decade, he adds.

他说：“由于成本，这通常是植物中最被忽视的部分之一。”“执行这些升级是昂贵的，但是我们不想只能将它们恢复到相同的容量而不会获得额外的效率。”

在2020年中期完成后，该设施已完全升级的设施每天能够从大脖子和周边社区处理530万加仑，不仅可以处理常规的住宅和商业废水流量，而且还增加了处理餐厅浪费的能力墨菲说，将从整个地区拖入。

“We wanted a way to have the new digesters become more of a fuel source for us, as well as a potential revenue source,” he adds, with haulers paying the district to unload grease, and that waste in turn helping the system generate more methane to power its microturbines.

The added revenue potential is a major benefit of the project, because even though the Great Neck district is a self-regulated utility with its own taxing ability, operations and budget, it still has to go through its home municipality for bond financing, Murphy says. “It helps to say, ‘We need to bond this much, but it’s only going to cost taxpayers this much,’” he says.

The $15-million project budget includes $14 million for the digester upgrades and new grease receiving facility and $1 million for the third microturbine, Murphy says. But the new microturbine, on which the team completed installation earlier this year, came in 26% under budget at less than $800,000, he adds. The project also tapped into government grants, including $500,000 from the New York State Economic Development Council in 2016. “These are incredibly grant-able projects,” he says. “When we generate energy on site, we free up energy capacity for the community.”

资金挖掘

The work also got help from former state Sen. Elaine Phillips (R), a Nassau County legislator who helped shepherd a $10.5-million grant through New York’s Transformative Investment Program. “I applaud the district’s … business-like approach to running the municipal plant and focusing on operational efficiency, increased revenue, all while being environmentally safe,” said Phillips, who lost her re-election bid in 2018.

这家大颈部植物在其106年的历史上进行了各种重大升级，稳步增加了能力并减少了环境影响，例如用更新的紫外线工艺代替氯消毒系统。

The plant uses four treatment stages—preliminary, primary, secondary and advanced—to remove solid waste via physical and biological processes, along with other methods to reduce toxicity of remaining liquid sludge. Digester systems are a central function in the advanced stage, stabilizing sludge by reducing “volatile content” and pathogens—a process giving off the methane that powers the microturbines on site.

墨菲指出：“厌氧消化剂通常是治疗设施中的第二大预算项目。”“它们就像胃一样 - 您必须喂食它们，您必须保持它们的加热以减少固体的数量和毒性，以将它们分解为水和气体。”

Greasing the Skids

墨菲说，该项目最大的新功能（添加了油脂摄入量单元）给了另一组挑战，部分原因是它不在标准的废水处理剧本中。只有少数美国工厂添加了这样的系统，因为它们需要大量的新基础设施才能从卡车上吸收废物，从运输者那里收取付款，升级消化器来处理除废水之外的油脂，并将额外的甲烷引导到现场共同发电。

Capano说，对于大脖子而言，增加油脂加工能力意味着建造一个新的2500平方英尺的消化材料建筑，该建筑将容纳卡车接收站和相关的电气设备。他说，新建筑的建设始于去年，现在已经完成了75％。

他说：“当我们从1和2消化器开始时，在[建筑物]上的工作仍在继续。”

墨菲说，处置商业油脂本身就是一个环境挑战，只有少数排放地点为卡车的排放地点，这些卡车从纽约大都市地区的数千家餐馆和其他企业中收集了此类废物。他说，大脖子让甘内特·弗莱明（Gannett Fleming）对需要额外处置地点的需求进行营销分析。他说：“每天都有大量的油脂在道路上行驶，只有几个斑点占据。”“运输者对在拿骚县建立设施的可能性非常积极。”

新设施的功能包括一个对接站，该站将润滑脂卡车钩到收藏和存储系统上；自动化驱动程序身份验证；数量计量和支付系统将产生提货账单和发票；以及与现有工厂SCADA（监督控制和数据采集平台）连接的集成步骤。他说：“我们不想要两个系统。”“那很麻烦。”

Developing a solution with automated capabilities was another prime goal, Murphy says. “We can have one staff member there when the truck is unloading just to supervise, but everything else, including having the systems cleaned and flushed, could be done by the SCADA system,” he says.

改进的消化

Taking in commercial grease for the first time not only means adding the intake station, but also an upgraded digester design, Murphy says. “Your anaerobic digester needs a good mixing and heating system and the ability to retain a lot more of the methane gas,” he says.

张说，这项工作包括升级各种机械和电气组件，例如管道，加热，泵，混合，传感器和污泥戒断系统。所有这些都将连接到现有的三个现有的238,000加仑，40英尺的混凝土储罐，它们将在工作期间保持原状。

墨菲说，一旦所有三个新的消化器系统都在线，该植物将大大增强甲烷的产生，因为通常以废水为食的细菌可以从油脂中获得很多里程。他说：“油脂是厌氧菌的非常可溶的食物来源。”“它使他们可以销毁更多的固体，而不是污泥，这需要更少的能量。而且它还使他们产生更多的甲烷。”张补充说，新的消化剂可以每分钟最多可产生50立方英尺的甲烷，即当前12至20 CFM的甲烷。

Supercharged Results

All of that extra methane will have somewhere to go with the project’s other big feature: the third microturbine. While the two existing microturbines today power 20% of the plant’s electricity and about 80% of digester process heating needs, the new systems—grease intake, upgraded digesters, boosted methane levels and a powered-up third microturbine—will help generate 195 kW to cover half of total energy use and 100% of digester heating.

墨菲说，大多数带有厌氧消化剂的废水植物通常在锅炉或蒸馏池加热中使用一小部分甲烷副产品作为能量，其余的则随着废物而燃烧。他补充说，新的系统工厂将捕获更多的甲烷作为能量，同时还可以节省较少的电网功率。

他说：“我们将在现场有大量的电力，包括冬季的100％热气，”。“基本上，就像为您的汽车提供免费的加油泵。”

By July, the project team expects to have all upgraded digesters in place, the grease intake system operating, and the third microturbine firing at full capacity, Capano says. It also aims to meet another goal: completing the work without community complaints. That’s no small task considering there’s an apartment complex across the street, he says.

“Odor control has been a big part of our construction activity coordination,” he adds. “We have had successful mitigation procedures in place. There were no odor complaints during the digester replacement.”