Home / Beltcon

<< Back

Development of Materials Handling Projects

Introduction
The development of a materials handling project would be in response
to the requirement to move material from point A to point B and possibly
store or change the nature or  condition of the  material en-route.
In many instances this may not result in a single task but a series of
tasks and may also incorporate disciplines other than materials
handling.
An overriding factor that applies to all projects is that the combined
project is cost effective.
It is no good developing a system where the capital and operating costs
cannot be recouped within the selling value of the transported material.
Neither is it satisfactory to consider materials handling equipment in
isolation. The whole project and all disciplines need to be considered in
their entirety.
It is for this reason that we use the various costing stages listed below
to enable the materials handling estimate to be integrated within a total
project cost evaluation.

Terminology

  • Concept +/- 50% 
  • Pre-feasibility +/- 30% 
  •  Feasibility+/- 15% 
  •  Design+/- 10% 

These estimates being staged to progressively refine the costs to both
justify a project or dispense with non viable projects.
As may projects involving materials handling also include other
elements of much higher value and complexity than the materials
handling, it is not unusual that the ‘Identify’ stage has already been
completed before we become involved or is bypassed.


Concept
The initial stage is to develop an understanding of the project and
establish a definition of the tasks required, such as -
• Rates, throughput and plant life.
• Characteristics of the material to be handled.
• Topography of the areas involved
• Location characteristics & climate
• Environmental limitations
• Interface with other disciplines and tasks
• Availability of power (and water where required)
• Define the extent of the scope of work


Refer to ‘Guidelines’ for guidance on the above items.
The most common approach is to develop a basic flow diagram of the
project and this requires that the following be determined -
• an appropriate concept
• the major equipment necessary for the task
• transport lengths
• storage capacities


Where sufficient information is not available from the client it is
necessary to make assumptions, to enable a preliminary analysis to be
commenced. It is also important to document the assumptions, which

will eventually be incorporated in a ‘basis of design’ if the project
proceeds into the more details stages.
Occasionally it is possible to short circuit some of the above detail
where a comparison is possible against a similar operating project, with
factors applied for the perceived differences.
From the above it is possible to prepare an order of magnitude costing,
usually without layout drawings. The following sections provide guidance on various items that need to
be considered in developing an appropriate concept for the defined
task.


Pre-feasibility
This stage indicates that the project has passed the initial cursory
assessment and warrants further consideration to refine the proposal to
identify any major risk areas and to improve the accuracy of the cost
estimate.
This stage requires layout drawings to enable quantities to be defined
and identify the extent of civil and earthworks.
Preliminary specifications are required to obtain budget pricing and
indicative drawings for major equipment.
Quantity take-offs are required for estimating.
A preliminary program would be prepared.


Feasibility
This stage requires that the flow diagram and layout drawings be
refined further to ensure that the proposed system is sound and that all
risks are identified and evaluated.
Decisions need to be made, and agreed with the client, on the form of
the contracts that will be issued defining the method of construction and
the extent of each contractors responsibilities.
The preliminary program would be refined but not taken to full detail
stage.
These decisions and timings would be used as the basis for the scope
of work for the specifications.
Specifications for major equipment would need to be refined and
extended to include and identify all requirements that will influence
performance and cost such that competitive quotes can be obtained
from multiple suppliers together with specific tender drawings, sufficient
to enable equipment selection to be made, possibly for advance
purchase of long delivery equipment as soon as the decision has been
made to proceed to the execute phase.


Design
This stage requires the preparation of full project information, equipment
specifications and documentation, including site lay down area
allocations for the various contractors, all suitable for obtaining contract
tenders for the full execution of the work required.
In addition to all the necessary drawings to define the scope and
interfaces for the various disciplines, a fully detailed program is
essential to ensure that deliverables are made in a timely manner for
the orderly progress of the works, without additional costs for delays to
other contractors or the need to pay acceleration costs. On a major
project the critical path program will be invaluable in identifying critical
delivery and interface items as well as assist with cash flow, cost
monitoring and manning of the project as well as any need for staged
deliveries.

Large projects require considerable on site monitoring and factory preinspections
to avoid slippage in specified delivery dates. Slippage which
is identified early enough can be corrected by the supplier/fabricator
without cost to the project.


Plant Selection Guidelines


Throughput capacities and required plant life


Road transport for short periods and lower throughputs.
Belt conveying for longer plant life and shorter distances.
Rail transport for long periods and distances.
- Overland conveyors are not more cost effective than road
transport for less than 5 years operation and 3mtpa.

Characteristics of the material to be handled -

Belt conveying for granular, lump and abrasive materials.
Lean phase pneumatic for light fine non abrasive materials.
Dense phase for heavy, fine and abrasive materials.
Hydroscopic materials will require air conditioning and covering.
Slurries and liquids are excluded from materials handling plants and
considered as ‘slurry/hydraulic handling’.


Topography of the areas involved


Troughed belt conveying for less than 18 deg up or 12 deg down
slopes.
Ariel ropeway for inaccessible terrain.
High angle conveyors for above 18 deg.
Topography can be used to advantage where there is a need for cone
stockpiling or high level entry into a plant, or underground reclaim

Location characteristics & climatic conditions
Enclosed equipment and possibly storage, for high wind and rainfall,
especially for dusty or hydroscopic materials.

Surface treatment

Remote locations can pose numerous problems including-
Manning and accommodation problems.
Equipment deliver/access load limitations.
Installation limitations
A preference for the delivery of preassembled equipment to reduce site work.


Environmental limitations


Spillage and dust limitations may require an enclosed facility.
Noise limitations or low temperatures may require special equipment/
materials and or enclosures.
Residential or sensitive area proximity may require enclosure.
Operating hours limitations.

Storage
Bins for small quantities. (less than 2000m3)
Stockpiles for large quantities.
Stockpiles, with the appropriate machines, can be used for blending of
materials. (Refer ‘Stockpile Machine Selection’ - TS4)

Treatment
Crushing and screening for size control and segregation.
Preparation plant for quality improvement/separation.
(Preparation plants are considered as a ’black box’ within a materials
handling plant as they involve ’process technology’)

Interface with other disciplines and tasks.
Rail transport systems.
Barge transport where there are draft restrictions.
Ship transport.
Areas required for process plant and associated facilities.
Spoil/reject disposal.


Availability of power and services
Power demand of system.
Water demand of system.
Staffing and accommodation.
Spare capacity in existing service facilities.
Support services.

Define the extent of the scope of work
Many projects are of limited scope with portions of a project being
handled by others. Where this is the case it is important to define the
limits of the scope and the interface information we are required to
provide.
At the ‘Execute’ stage every battery point must be specifically defined
and located.

Sizing of equipment
When determining equipment rated capacities it is important to apply a
suitable overall utilisation factor to the nominated annual throughputs to
allow for the inevitable losses which always occur.
The ‘overall utilisation’ factor is deemed to include both the Utilisation
and Availability factors.

These inevitable losses include -

  • Breakdowns and blockages.
  • Material availability, discontinuity in truck/rail deliveries.
  • Shift and route change losses.
  • Hatch change losses, of shiploaders.
  • Flow rate variation, of reclaimers.
  • Stockpile machine relocation.
  • Filled bin signals.

Typical factors (F1) are indicated below, depending which items of
equipment are in the sequence.
Multi entry & exit. conv system— 60%
Single entry & exit conv system— 65%
Single route conveyor system— 80% max
Stackers— 65% max
Reclaimers– 50% max
Shiploaders— 40% min, 80% max, depends on
ship frequency available berths and
operating hours.
Train Loading 50% replica orologi di lusso
Additional allowance (F2) should be made where site operating times
are less than 24hrs/day, 360 days/yr (nominal). The operational
restrictions may be due to community/environmental considerations or
the potential for severe weather conditions.
Rated capacity = Annual Throughput (Mtpa)
360*24*F1 *F2