解决地下基础设施问题的复杂性

案例研究

Occupational awareness continues to grow around buried infrastructure damage-prevention and employee protection in the utilities and infrastructure market segments. Hydro excavation operations have grown tremendously as the primary means of addressing this problem and this trend is expected to continue.  Further exponential growth in hydro excavation requirements will be required to address the following realities:

  • Our aging infrastructure
  • The ongoing population growth of urban centres and planned densification
  • The maintenance requirements to sustain this growth

BUT, the increased utilization of hydro excavation to address these necessary and vital requirements creates an additional issue – what to do with the excessive wet waste slurry generated from these operations now contained in the vessel on the truck. The current methodology of filling the vacuum truck to it’s weight restrictions (already a complex calculation that may vary by axle weight, gross weight, municipality or seasonality) and then transporting that material to an approved receiving site to dump the material for treatment and then returning to the work site is extremely time consuming and very costly.

Operators can expect these costs to continue rising as a result of several factors including:

  • Regulatory changes and enforcement have reduced load volume and weight so cost per cubic metre have escalated.
  • Limited off-loading facilities and capacity in reasonable proximity to urban projects have led to supply deficit rate increases
  • Cash strapped municipalities looking for alternative revenue streams and road maintenance cost offsets are hiring enforcement officers
  • Wait times at approved disposal facilities have increased demurrage cost.

To further complicate the situation, it can be expected that some of the hydro-excavated material will be contaminated with residual elements from our industrial or ill-informed past practices, underground tank seepage or even road salt. Consequently, the soil needs to be characterized to avoid risk to the environment and human health.

Ideally the solution includes, maintaining the advantages of hydro-excavation’s safe and efficient underground utility exposure but eliminating the inefficient and costly transportation of wet waste slurry in vacuum excavation trucks to a limited number of expensive receiving sites.

Slurry solidification technology can help.

Uniquely designed equipment and environmentally-friendly reagent, will work together on-site or near-site to convert the excavated wet soil to a dry stackable material for transport using dump trucks.  This efficient and effective process provides positive results for the project by:

  • Reducing the number of trucks required to move this waste material by 2/3rds
  • Improving the efficiency of hydro-excavation vacuum trucks by eliminating the need to drive to a disposal site every 4 cubic metres excavated
  • Accounting for the soil excavated and its final resting place to mitigate risk
  • Reducing green house gas emissions by 65%
  • Reducing costs

Slurry solidification technology may not be a panacea for all projects but should be seriously considered as a component for projects addressing buried infrastructure.

卡博内郡世界自然基金会泻湖

主要利益相关者:

业主 淡水河谷加拿大有限公司
承包商: Tervita 公司
经销商: Di-Corp

VALE-tervita-di-corp

挑战

淡水河谷公司在加拿大安大略省北部拥有并经营着一个采矿场。通过采矿和精炼活动,他们产生了一种污泥废物副产品。客户需要一个高效的挖掘和运输解决方案,将这些污泥运到场外的垃圾填埋场。

日期

2018 年 9 月底 - 2018 年 10 月中旬

解决方案

在竞标过程中,MetaFLO 参与提供了最佳的混合料和加料率,以达到污泥挖掘和运输所需的固体标准。MetaFLO 利用分析数据估算出的剂量率为 1.1%(按重量计)(基于高含水量)。建议使用大型搅拌桶,以增加表面接触,提高桶搅拌过程的效率。目前尚未获得样本。

结果

Tervita 公司利用 MetaFLO 试剂固化了约 4,000 立方米的污泥。现场有两个 35 立方米的垃圾箱,装载着 "较重 "和 "较轻 "的污泥。最初估计的用量是准确的,因为实际处理平均每立方米污泥大约需要 30 磅 MetaFLO MF006 试剂。所有材料都被安全地运往淡水河谷的场外垃圾填埋场。工作按时完成。