Recycling and composting: purity, moisture and changing input

The purity of sorted fractions varies from day to day

What happens. A sorting plant separates mixed waste into materials with optical sorters, air jets and screens. The input changes with the season, the collection and the day, and the sorters are set once. Purity of the fractions is known only from the sample taken now and then.

What it costs. A fraction that is not pure enough sells for less or is rejected. Setting the sorters very tight to be sure loses good material to the residue.

Why the usual fix fails. Manual sampling shows what happened hours ago. Settings based on the experience of one shift are not passed on and do not follow the change in the input.

How a fixed-price remote diagnosis checks it. From sorter logs (ejection rates, belt loads, sensor signals), sample results and input data, I check whether purity can be estimated while the material runs and whether settings can adapt to it. The fixed-price remote diagnosis tells you how well that works for your fractions.

Background: Control that adapts to drift and wear

Moisture and temperature in compost heaps are unknown

What happens. Compost heaps are turned and watered by calendar or by smell. Inside a heap, temperature and moisture differ from one spot to another, and a probe tells about one point.

What it costs. Odour complaints from neighbours when a heap goes anaerobic, compost that is not stable and a long rotting time. Water is spent where it is not needed.

Why the usual fix fails. Turning more often keeps the heap aerobic and costs diesel and time. Probes at some points miss the inner parts of the heap.

How a fixed-price remote diagnosis checks it. From heap temperature probes, weather, turning and watering records and the input mix, I check whether the heap state can be estimated and the turning planned on it. The fixed-price remote diagnosis tells you what the estimate adds to what you see today.

Background: Computed measurements

Biowaste for digestion changes from load to load

What happens. The digester receives kitchen waste, garden waste and food residues in changing mixes. The gas production rises and falls, and the operator adds more feed when the gas falls, then finds the digester overloaded a few days later.

What it costs. Gas yield below the potential, sudden acidification and the days of recovery that follow. Gas engines that run at part load because the gas does not arrive.

Why the usual fix fails. Feeding according to a fixed recipe ignores what the load really contains. Lab analysis of every load is slow and costly.

How a fixed-price remote diagnosis checks it. From feed records, gas production and composition, temperatures and acid values, I check how the mix can be estimated and the feed adapted to it. The fixed-price remote diagnosis tells you what a feeding plan could improve.

Background: Control that adapts to drift and wear

Light-packaging sorting: shrinking capacity and wrong items in the bin

What happens. Plants that sort light packaging from the yellow bin run at high automation, but some close because of energy prices and costs, so the remaining plants take more input. A large share of what arrives does not belong in the bin, and the mix changes with the collection region.

What it costs. Purity and revenue fall when the input varies and items are misplaced. Throughput limits are reached at the sorter and the belts, and an extra shift costs staff the plant does not have.

Why the usual fix fails. Setting the sorters for a normal day does not hold when the input changes. More manual picking costs staff and is hard to find.

How a fixed-price remote diagnosis checks it. From plant data (belt loads, sorter ejections, sensor signals) and the lab results of the fractions, I check where throughput and purity are lost and whether control from sensor data could hold both. The fixed-price remote diagnosis tells you what to adjust first.

Background: Predictive control of process plants

Stricter contaminant limits for biowaste put compost loads at risk

What happens. Rules limit how much plastic, glass and metal may be in biowaste, and collectors inspect bins. Composting and digestion plants receive loads with contaminants that they have to find and remove, or reject the delivery.

What it costs. Rejected loads, compost with more contaminants than the quality mark allows and sorting steps that cost staff and machine time. The final product loses value.

Why the usual fix fails. A visual check at the weighbridge sees what lies on top. Extra sieving and sorting stages cost energy and lose organic material together with the contaminants.

How a fixed-price remote diagnosis checks it. From intake records, sieve residues, quality results and the process settings, I check whether the contaminant content of a load can be estimated at the intake and how the process should react to it. The fixed-price remote diagnosis tells you what is realistic.

Background: Computed measurements