To nie tyle śmieci, co surowiec wtórny.

Here to means this / it / that in a very general way. It often introduces a definition, identification, or reclassification.

So To nie tyle śmieci, co surowiec wtórny is structurally like:

• This is not so much trash as recyclable material
• It’s not really trash, but rather a secondary raw material

In Polish, sentence-initial to is extremely common in statements like:

• To jest problem. = This is a problem.
• To mój brat. = This is my brother.

In your sentence, the verb jest is simply omitted, which is very natural in Polish.

Nie tyle ..., co ... is a fixed contrast pattern meaning something like:

• not so much X as Y
• not exactly X, but rather Y
• less X than Y

It does not completely deny the first idea every time; instead, it shifts the emphasis to the second one.

So:

• To nie tyle śmieci, co surowiec wtórny. = It’s not so much trash as raw material for reuse/recycling.

Other examples:

• To nie tyle krytyka, co rada.
  = It’s not so much criticism as advice.
• On nie tyle pomaga, co przeszkadza.
  = He’s not so much helping as getting in the way.

This is a fairly elegant, slightly formal way to contrast two descriptions.

Formally it is the same word, co, but here it does not mean what.

In this structure, co functions more like:

• but rather
• as
• than in a contrastive sense

So in nie tyle X, co Y, you should treat the whole expression as a set phrase, rather than translating co word by word.

Compare:

• Co robisz? = What are you doing?
  Here co = what

but

• nie tyle X, co Y
  Here co is part of a comparative/contrastive pattern.

Because Polish very often omits jest (is) in present-tense sentences, especially when one noun phrase is being equated with or reclassified as another.

So these are both natural:

• To nie tyle śmieci, co surowiec wtórny.
• To nie tyle śmieci, co jest surowiec wtórny. ❌

You would not normally add jest inside this sentence the way English requires is.

A fuller version might be:

• To nie są tyle śmieci, co surowiec wtórny — but this sounds much less natural.

The short verbless version is the idiomatic one.

Śmieci is the normal plural form of śmieć / śmiecie in modern usage, but in practice it often works like a mass noun meaning trash / garbage / rubbish.

So even though it is grammatically plural in form, it can refer to trash in a general, uncountable sense.

Examples:

• Wyrzuć śmieci. = Take out the trash.
• To są śmieci. = This is trash / These are trash.

In your sentence, śmieci is in the nominative plural form because it is one of the contrasted labels in the nie tyle X, co Y structure.

Because the sentence contrasts two different ways of classifying the same thing, and each expression keeps its own normal form.

• śmieci is naturally used in the plural form
• surowiec wtórny is a singular countable noun phrase meaning secondary raw material or recyclable material

Polish does not force them to match in number in this kind of contrast.

This is similar to English sentences like:

• It’s not trash, it’s a resource.

Even though trash behaves like a mass noun and resource is singular countable, the contrast still works.

Literally, surowiec wtórny means secondary raw material.

In practice, it refers to material that can be recovered and reused in production instead of being treated as mere waste. Depending on context, English translations could be:

• recyclable material
• recovered material
• secondary raw material

The adjective wtórny means secondary, derived from reuse, or not primary/original in this context.

So the phrase has a technical or environmental feel. It sounds more formal than everyday words like:

• recykling
• materiał do recyklingu
• odpady do przetworzenia

Yes, in standard writing you should use the comma in this construction:

• nie tyle X, co Y

So:

• To nie tyle śmieci, co surowiec wtórny. ✅

The comma helps mark the contrast and is the normal punctuation here.

It sounds fairly formal or polished, especially because of two things:

• the structure nie tyle ..., co ...
• the phrase surowiec wtórny

A casual speaker might say something simpler, for example:

• To nie są śmieci, tylko coś do recyklingu.
• To nie śmieci, tylko surowiec do odzysku.

Your original sentence sounds like something you might hear in:

• environmental campaigns
• public speaking
• journalism
• official or persuasive writing

Yes. It is a productive pattern and can be used with nouns, adjectives, and even verbs.

With nouns:

• To nie tyle hobby, co praca.
  = It’s not so much a hobby as a job.

With adjectives:

• Był nie tyle zły, co rozczarowany.
  = He was not so much angry as disappointed.

With verbs:

• Nie tyle odpoczywał, co unikał obowiązków.
  = He wasn’t so much resting as avoiding responsibilities.

It is especially useful when you want to correct or refine a description rather than reject it completely.